Duration: 10/01/2021 to 09/30/2026

Administrative Advisor(s):

NIFA Reps:

Non-Technical Summary

Statement of Issues and Justification

There is widespread public concern regarding animal welfare in the United States. Evidence for this concern, and how it affects the long-term sustainability of animal use, is apparent in numerous stakeholder initiatives to address this issue. For example, agricultural sectors have developed standards of care and then verify compliance with these; the list of audit or assessment programs currently include the North American Meat Institute Audit of livestock slaughter, United Egg Producer’s audit, National Milk Producer’s Federation Farmers Assuring Responsible Management program, and the Common Swine Industry Audit. Among these initiatives, there widespread support for the idea that decisions about welfare should be based on scientific evidence. Indeed, other stakeholders, such as agricultural universities, also recognize that standards of care of agricultural animals should be based on science. The Ag Guide, the US standards of care for agricultural animals used in research and teaching, is informed and revised every 10 years to reflect the latest research in this area. Finally, animal welfare plays a role in world trade as evidenced by the recent establishment of global animal welfare standards on transport and slaughter by the World Organization for Animal Health (OIE). The OIE continues the development of standards and recommendations in new areas of importance to animal welfare and it is important that these standards be based on scientific evidence.

Through NC-1029, we have established a national scientific committee to generate and disseminate objective scientific information on animal welfare issues. This committee is comprised of approximately 40 scientists working in multiple disciplines at different locations throughout North America. Our research is critical to provide the science and technology to help stakeholders, including those in the agricultural sectors, education and at the global level, make informed decisions about standards of animal care.

Related, Current and Previous Work

The proposed 2021-2026 version of NC-1029 builds on our 15 years of previous work in the area. There are several other multi-state projects working in related, but different areas. NE-1042 (Poultry production systems: optimization of production and welfare using physiological, behavioral and physical assessments) investigates production systems in only one species, whereas our project will emphasize both the discipline of animal behavior as well as other livestock. W3173 (Impacts of Stress Factors on Performance, Health, and Well-Being of Farm Animals) also addresses aspects of animal welfare, but their focus is more on management practices rather than specifically measuring behavior or about application of this information in animal welfare assessment programs. A newly established multistate project, NC-1211, Precision Management of Animals for Improved Care, Health, and Welfare of Livestock and Poultry, is synergistic with NC-1029 and there is overlap in our membership. We will coordinate efforts with NC-1211.

Over the last 10 years, the field of animal welfare has continued to grow. There is considerable media attention on practices such as using cages for laying hens and tail docking dairy cattle. The role of scientists in the societal discussion of how to best treat agricultural animals is considerable (Mench, 2008). There are several areas where these contributions are particularly notable: proliferation of precision farming or automated measurement of animal responses, additional novel indicators and new applications of existing animal welfare measures, and the rigor and scope of on-farm welfare assessment.

Automated measurement of animal responses

As livestock and poultry industries shift to housing animals in larger social groups and more complex environments, it becomes increasingly difficult to monitor individual animals. Yet, in order to assess welfare, it is essential we understand the response of individuals to systems as welfare is a characteristic of an individual animal, not of a group. Conducting direct observations of animal behavior or intensive monitoring of animal health is time consuming and requires trained, highly skilled employees. Furthermore, when large numbers of nearly identical looking animals are housed together in a large group, it becomes nearly impossible to visually observe all members of the group and to recognize them as individuals. Advances in technology, both in sensors that are wearable by animals and in equipment that allows us to measure environmental characteristics at the level of the animal itself may be a way to overcome these challenges and provide a means to track animals over a period of time. In addition, historically, environmental control has been based on a classical engineering approach to technology, specifically for providing optimal thermal comfort based on a set point condition or controlling lighting or feeding on a set schedule. This prescriptive approach to animal housing and husbandry resulted in the ability to increase the scale and intensity of animal production. One deficiency in this approach is that it focuses only on one or two main environmental parameters and neglects other potentially relevant ones. Another deficiency in this approach is that it takes a one-size-fits all approach to the needs of the animals under a given set of conditions. Advances in technology are moving quickly toward viable on-farm capabilities to offer real-time monitoring of individuals or groups of animals. Real-time monitoring of animal responses provides the potential to tailor animal management, which simultaneously increases our ability to address welfare needs of individuals and while more effectively directing resource inputs (Norton and Berckmans, 2018).

Body-worn sensors for recording physiological variables such as heart rate, body temperature, and respiration rate have been developed (Brown-Brandl et al., 2003; Eigenberg et al., 2007), and other types of body-mounted sensors, including pedometers, active transponders, accelerometers, and position detectors, provide additional information about animal behavior (Brehme et al., 2007; Müller and Schrader, 2003; Pépin et al., 2006; Scheibe et al., 1998). Small wireless body-worn sensors capable of detecting general levels of activity, specific behavior and location of hens relative to other hens as well as ambient and skin temperatures have been developed and validated at Michigan State University (Quwaider et al., 2010; Banerjee et al., 2012, 2014; Daigle et al., 2012, 2014). Such systems represent an approach to detecting specific information about the behavior and physiology of individual animals while linking this to the environmental context. Developments in precision agriculture, as in the dairy industry, have resulted in a proliferation of commercially available sensors and systems for capturing information at the level of the individual animal. These sensors typically record activity of the animals as well as rumination and lying time and have been correlated with visual assessments of these behaviors (Schirmann et al., 2009; Ledgerwood et al., 2010; Elischer et al., 2013; Bikker et al., 2014). However, at present, many producers and researchers do not yet take full advantage of these data, although some research has shown that there is a relationship between behaviors recorded by these sensors and dairy cattle health and welfare assessment metrics, such as lameness and leg lesions (e.g., Liboreiro et al, 2015; Westin et al., 2016).

Computer vision and other methods for remotely detecting animals and their behavior have potential to provide data from animals housed in large groups that could be also be used to monitor, manage and assess animal welfare (Ellen et al., 2019; Wurtz et al., 2019). In contrast to body-mounted sensors, remote sensors are mounted in the environment.  Remote sensing technologies include devices such as readers for identification tags (e.g., RFID detectors), recording devices that can detect sounds of animals and their environment (e.g., microphones), and a variety of vision-based technologies (e.g., monochromatic, color, 3D depth-sensing, infrared, and thermal cameras) that can provide information about animal distribution in space, animal postures and behaviors, interactions among animals, and information about physical characteristics of the animal such as shape, color, body condition, lameness or animal temperature (Wurtz et al., 2019). For example, depth-sensing cameras have been used to detect aggression, feeding, drinking, and playing with drinkers in piglets housed in small groups in nursery pens (Chen et al., 2019, 2020a,b,c). In addition to use of sensors to monitor the behavior and welfare of animals on farm, using monitoring technologies in abattoirs has the potential to identify animal welfare risks during transport, stunning, and slaughter procedures as well. Controlled atmosphere (CAS) stunning systems have perceived animal welfare benefits compared to electrical stunning (reviewed in Berg and Raj, 2015) because individual handling of birds pre-slaughter is not necessary. However, in CAS systems it is more difficult to identify animals that die before slaughter (dead-on-arrival or DOA birds) (Thaxton, 2018). Current and emerging technologies, such as thermal imaging, may facilitate easier and more timely identification of DOA animals, but research in this area is lacking.

Additional novel indicators and new applications of existing of animal welfare measures

In addition to automated measures, work is needed to identify other indicators of animal welfare and to explore existing indicators in a wider range of situations. Promising novel parameters include deepening our understanding of pain, effective environmental enrichment, early developmental factors influencing animal welfare later on including social behavior, as well as factors at euthanasia and slaughter that influence animal welfare. Understanding the role of humans in these decisions is also an important area of new research.

Pain

Established welfare indicators of pain have been used to evaluate pain associated with procedures such as disbudding or castrating cattle immediately after these procedures (Coetzee, 2011, Stafford and Mellor, 2011), but much less is known about how the long these wounds take to heal, nor how painful they remain during this process. Recent work with hot-iron disbudding indicates that calves given analgesia 11 d after disbudding show behavioral changes consistent with reduced pain (Adcock et al, 2020), and 3 wk after disbudding, calves are more likely to choose an environment paired with analgesia than their non-disbudded counterparts (Adcock and Tucker, 2020). Together, these findings indicate that calves continue to experience pain during the healing period even when the wounds are not being stimulated.

Surgical castration remains the most common approach to avoid boar taint in pork products that originate from males. This procedure is painful and causes short-term and long-term distress and behavioral modification. Recognizing pain in piglets could be a valuable tool to manage pain and could be the first step to routine analgesia use. A piglet grimace scale was previously validated (Viscardi et al., 2017; Viscardi and Turner, 2018), but is not yet used in the US swine industry. Furthermore, the impact of analgesia during castration on short-term and long-term affective states needs more investigation.

Finally, it is not only routine procedures that cause pain. Lameness is a pervasive problem in the dairy industry that diminishes animal welfare. Lameness negatively changes the physiology, behavior, and affective state of affected cows. Sole ulcers (SU) are a common (affecting ~ 10% of cows), painful cause of lameness that frequently causes permanent damage to the hoof. Intervention research on SU is necessary for the dairy industry to address the pain associated with both the treatment and disease process. Lameness has been the subject of many previous studies (Cook et al., 2018), but relatively few have focused specifically on the pain aspect of the problem.

Effective environmental enrichment

Environmental enrichment refers to improvements to captive animal environments (Newberry, 1995). Well-designed enrichments within an environment should present objects and situations that act successfully and with a foreseeable rewarding outcome (Manteuffel et al., 2009). The term enrichment can be used to describe changes in the environment (e.g. social, physical, sensory, feeding, or taming) and some authors use enrichment as a synonym for an increase in environmental complexity. However, there is a need for more standardized, species-specific methods and criteria for assessing whether enrichment has occurred (Manteuffel et al., 2009) or that an enrichment program has been successful.

Early development, including social behavior

In addition to the specific resources available within animal housing environments and the configuration of these resources, an animal’s early experiences can have numerous, long-lasting effects on the animal’s ability to cope with its environment and productivity later on. As livestock and poultry production shifts to housing animals in more complex environments that provide greater behavioral and social opportunities, it will be important to identify how early rearing factors influence indicators of animals’ success in their respective environments. Research has demonstrated the importance of rearing animals in environments similar to the production environments that they will ultimately be housed in because the rearing environment enables animals to develop the skills necessary to effectively navigate and use resources within the production environment (Janczak and Riber, 2015). For example, the inability of cage-reared laying hens to navigate complex, multi-tier housing systems reduces their ability to locate food and water on higher tiers and increases risks of eggs being laid on the floor (Tauson, 2005). However, problems with floor laying and resource use in alternative laying hen housing systems persist, and these behavioral issues can serve as indicators of the suitability of the animals’ environment. For dairy calves, research into the effects of the social environment is increasing, partly driven by the recognition of the detrimental effects that social isolation has on calf welfare and the positive effects that social housing can have on indicators of stress susceptibility and social bonding between animals (reviewed in Costa et al., 2014). However, many questions about the long term benefits of social housing on dairy calf welfare remain, and how to identify these benefits when considering specific sensitive periods for socialization and whether early socialization can serve as a buffer against specific stressors.

On-farm welfare assessment

Agricultural sectors have developed on-farm care standards and verify compliance with these standards through assessment or audits. In the US, participation in these programs is widespread: it is estimated that 98% of the nation’s beef and pork are slaughtered in plants participating in the North American Meat Institute Audit, 90% of eggs produced in the US are certified under the United Egg Producers’ audit, 98% of dairy farms engage in the National Milk Producer’s Federation Farmers Assuring Responsible Management program, and finally, the goal of the Common Swine Industry Audit is to eventually reach all pork producers. There are several challenges faced by these types of programs. For existing programs, there are questions about the appropriateness of methods used to gather information on farms as well as the key variables to include for identifying compromised animal welfare.

In some existing audits or assessments, we have made progress in determining the appropriate variables to include and the appropriate number of animals to sample. For example, with dairy cattle, it is widely accepted that lameness is a key animal welfare concern and that 30%+ of the lactating pen must be scored to generate an accurate estimate for a given farm (Endres et al., 2014). However, more information is needed about the risk factors for problems such as lameness, thus while epidemiological work and benchmarking has been conducted under some conditions (e.g., freestalls in California and North East, Chapinal et al., 2012 and Midwest, Espejo et al., 2006 and Espejo and Endres, 2007), additional research is needed to cover a wider range of geographic areas (e.g., South East) and for all of the variables included in such assessments (e.g., risk factors or acceptable levels for cattle dirtiness has not been well studied from an epidemiological perspective). Similarly, questions around appropriate sampling (e.g., how many and how to choose which animals to measure) remain. For example, the transect walk method for evaluating the welfare status of birds in commercial poultry flocks was developed by Prof. Estevez and colleagues, and has been shown to have great promise in initial evaluations conducted on broiler (Marchewka et al., 2013) and turkey (Marchewka et al., 2015) farms. Further work is needed to test this method further with turkeys and with previously unstudied species such as ducks.

In addition, as existing audits and assessments have become more widely used, there has been growing awareness of compromised animals on commercial farms. In the case of pork production, this has created demand for better ways to both identify compromised animals as well as decision criteria for euthanasia (Morrow et al., 2006; Ontario Farm Animal Council, 2010). In the case of dairy cattle, it has created demand for improved technology to identify at-risk animals earlier, thus limiting suffering and improving opportunities for successful intervention. (Schirmann et al., 2009; Bikker et al., 2014).

Other species have received relatively little attention from an animal welfare assessment/audit perspective, for example, cage-free egg production and ducks.

Eggs. Many US producers are moving from housing hens in conventional cages to keeping them in cage-free systems due to increasing demand for cage-free eggs (Scheier, 2016). However, very little is known about the prevalence of welfare problems in commercial cage-free laying hen flocks in the US (Lay et al., 2011) although some work has been conducted in Europe (Rodenburg et al., 2005; Tauson, 2005; Tactacan et al., 2005). As with dairy cattle above, information is needed in terms of prevalence of common problems (benchmarking) and epidemiological work identifying risk factors for key animal welfare concerns.

Ducks. There has been no peer-reviewed research published comparing or comprehensively evaluate the accuracy of methods or programs used to assess the welfare of commercial ducks. Published research pertaining to commercial duck welfare has instead focused largely on comparing provided resources, such as mode of water provision (e.g., O’Driscoll et al., 2011) or flooring type (e.g., Karcher et al., 2013).

Understanding human perspectives

Changes to production systems that improve animal welfare on commercial farms are often slow to be implemented, even after research has demonstrated the effectiveness of particular modifications to management practices or housing systems (Millman et al., 2004). Changes may be costly for livestock and poultry farmers, requiring infrastructure alterations or increased labor, and, additionally, the farmers may not fully understand the implications of the welfare problem or consider the situation to be of sufficient concern that requires a remedy (Ison et al., 2018). Changes to improve welfare often also require input, buy in or pressure from other stakeholders, including retailers who are willing to sell or differentially market “higher welfare” products, and consumers who are willing and able to purchase potentially higher priced products (de Lauwere et al., 2012). Thus, understanding the perceptions of the humans in a particular supply chain from conception to consumption is critical to effecting positive changes to agricultural animal welfare.

In some cases, farm personnel may not recognize a welfare problem, either due to lack of training, desensitization, or perhaps cognitive dissonance (Peden et al., 2019). While there is evidence that swine farmers perceive aggression to be a problem when they witness a fight, they do not view the consequent injuries and exhaustion as impacting welfare to the same extent that non-farmers do (Peden et al., 2019). In other cases, even if stockpersons recognize a problem, they may not be using appropriate strategies to mitigate it. For example, research at Michigan State University has found that US pig producer perceptions of the usefulness of techniques to minimize aggression do not correspond with results of scientific studies (Ison et al., 2018), with the result that techniques used by producers to minimize fighting among pigs are likely not very effective. The limited uptake of scientific recommendations to improve welfare in practice may be due to low prioritization of the welfare problem combined with practicalities of implementation, lack of information on cost-effectiveness and ineffective communication of research to the farming community (Peden et al., 2018). To ensure behavior and welfare research findings are implemented in commercial animal agriculture, people working in livestock and poultry industries must be involved in the design of practical solutions.

For example, on commercial farms Precision Livestock Farming (PLF, the use of technology to continuously collect and process data from animals) can be used to mitigate labor problems and PLF can simultaneous improve animals’ production efficiency and their health and welfare, which are often seen as competing or contradictory goals (Guarino et al., 2017). However, to achieve these goals, PLF must actually be adopted and used by the animal agriculture industries. Yet, uptake of PLF by animal agriculture has been slow (see Shepherd et al., 2018 for a synopsis). To facilitate successful adoption of PLF technologies, human end users need to be involved throughout their development to create usable and economically viable solutions for farms (Busse et al., 2015). It is critical to develop a forum in which scientists, farmers, veterinarians, certification organizations, technology developers and consumers can actively engage and shape the future of PLF technology used in animal agriculture production in a collaborative way (Eastwood et al., 2017).

For any on farm welfare assessment to be successful, there must be acceptance of and willingness to use the tools by the humans who must carry out the assessment. Research examining producer perceptions of animal-based welfare measures and the tools used to collect them, including precision livestock farming technology as well as less technical management practices related to nutrition or housing, must be conducted to ensure that science-based assessments can be carried out on farms. Ultimately, public trust in welfare assessment standards, audits and certifications is also needed to ensure that welfare-friendly products are purchased and that animal agriculture retains its social license to produce animal products.

Similarly, research is needed to understand producer and stockperson attitudes about end-of-life decisions for farm animals, because conditions surrounding end-of-life events are as important to animal welfare as events occurring throughout the rearing period. There is increasing recognition of the role that stockperson attributes (experience, attitude, demographic factors and training) play in implementing euthanasia protocols on farms (e.g. Rault et al., 2017). To advance humane euthanasia, there is a need to examine factors affecting stockperson strain and effectiveness associated with implementing euthanasia methods.

Objectives

1. To develop novel behavioral and physiological indicators of animal welfare or apply existing measures to generate novel knowledge or applications
   Comments: There is a need to develop novel, preferably non-invasive techniques, to measure animal welfare and to apply existing measures to new or emerging contexts. Both behavior and physiology can be used as indicators of welfare, and generate novel data to address current and emerging areas of welfare concern.
2. To strengthen the scientific basis of animal welfare assessments and standards
   Comments: Many animal welfare assessments and standards have been introduced in the US in recent years. However, relatively little is known about the robustness of our ability to measure animal welfare, particularly in terms of sampling decisions, repeatability and feasibility of measures within an assessment framework. The appropriateness and feasibility of when and how to use measures within the 3 broad categories (resource-, outcome- and management-based) at a group or facility level need to be investigated.

Methods

Objective 1

A number of projects will be conducted to address this objective, including the development and validation of automated methods for measuring welfare, including disease and response to housing and management practices. Other novel measures or applications include the evaluation of pain, environmental enrichment, early development and social behavior across a range of sector-specific contexts. Additional projects to the ones described in this outline will be developed within the next five years.

Development and validation of automated methods for measuring welfare of individual animals

In poultry. A sensor system for laying hens under development at Michigan State University detects the performance of key behaviors performed by poultry including dust bathing, feeding, walking and jumping down from perches. Data collected from such sensors will be integrated with data from other hens and house-level information about air quality, temperature, or even feed consumption. Integrated multi-modal data such as this will provide robust information that can be used to monitor the welfare of individual birds. In addition to understanding use of key resources in alternative housing for laying hens, newer housing systems, including conventional cage systems with lower bird densities, floor systems, vertical aviaries and various free range systems, present their own unique challenges to both design and management for balancing a comfortable environment and energy efficiency. Specifically, atmospheric ammonia is known to be a significant challenge to control, and elevated concentrations have been linked to decreases in health and production. University of Illinois will address a gap in scientific knowledge by using technology to address questions about concentrations and durations of ammonia exposure result in challenges for hens, which could be evidenced by biological or behavioral changes. Finally, Texas A&M University will compare the use of thermal imaging to detect and quantify lameness to traditional methods such as gait and lesion scoring. Broilers of different ages and weights will be assessed under research conditions as well as on-farm. The aim of this research is to provide a tool that can be used for lameness monitoring and rapid determination.

In cattle. A recent review (Rutten et al., 2013) summarized 126 dairy cow studies on sensors worn by individual cows. Most of those studies were focused on mastitis and fertility, with limited work on transition cow health. University of Kentucky, Washington State University and University of Minnesota will investigate the use of sensors to identify cows at risk for health disorders, especially during early lactation when a large percentage of cows die or are culled (Shahid et al, 2015), resulting in economic loss for the dairy industry and representing a serious welfare problem. In addition, feeding behavior collected from automated calf feeder software will also be evaluated by University of Florida and University of Minnesota as a predictor for disease and to investigate response to stressors (including competition, changing group dynamics, painful procedures and illness). The sensors used by these stations are often either already developed, but have not been tested for welfare assessment, or are currently under development.

University of Oregon will investigate whether thermal camera technology can be used to evaluate if new approaches to non-invasive stress detection can be accomplished in ways that are user friendly and economically feasible in a variety of applied settings. Thermal imaging technology also has applications to advancing stunning and slaughter methods. Research is needed to examine specific animal-related factors, beyond stunning methods themselves that influence animal welfare. Research will be conducted at Auburn University to develop methods for the early identification of dead on arrival (DOA) poultry using thermal imaging technology. Additional research at Auburn University will examine how the birds’ physiological status influences controlled atmosphere stunning (CAS) parameters to optimize bird welfare and meat quality.

Pain in dairy cattle and pigs

Pharmaceuticals are a powerful tool in the assessment of pain as they manipulate the subjective experience of the animal. In agricultural species, the most common agents used are local anesthetics and non-steroidal anti-inflammatory drugs (NSAIDs), likely because these are relatively practical options to mitigate pain associated with procedures or injury. At the University of California and University of Wisconsin-Madison, a novel approach will be used to limit pain during disbudding or prevention of horn growth in dairy calves. These stations will use an ethanol nerve block to create longer-lasting pain relief following application disbudding with caustic paste. Pain will be evaluated through both evoked (e.g., mechanical stimulation of the wound) and spontaneous behavioral responses.

At Virginia Tech, researchers are conducting a survey-based study to evaluate the feasibility of the piglet grimace scale, a way to detect pain, for the commercial swine industry. They will distribute an online survey to both industry-experienced participants and members of the general public and ask them to apply the piglet grimace scale to 12 scenarios. In addition, the researchers at Virginia Tech will study the affect of surgical castration with or without analgesia on affective states using an attention bias test.

Finally, using a combination of an experimental challenge model and epidemiological methods researchers at the University of Minnesota will evaluate both pharmacological and non-pharmacological interventions to both treat, prevent and reduce the pain associated with lameness caused by sole ulcers.

Effective environmental enrichment

In poultry. Leg health and lameness in broiler chickens and turkeys is one of the most important welfare problems in farm animals. Lameness issues are often related to high growth/body weights and low levels of activity and this is why researchers have focused on environmental enrichments that stimulate locomotor behavior (Riber et al., 2018). The University of Maryland will investigate the effects of structural and lighting enrichments on the behavior and leg health of broilers. Research at Purdue University will examine effective enrichments for turkeys, focusing on injurious pecking behavior and possible effects on turkey leg health. Virginia Tech will investigate the effect of environmental complexity (through permanent and rotating enrichments) and stocking density on broiler chicken welfare. The two main objectives of the Virginia Tech study will be to (1) evaluate novel biomarkers for association with affective state and cumulative welfare status, and (2) identify effective environmental enrichments, based on the frequency of interactions and types of behaviors elicited, and based on birds’ cognitive bias. This would be the first study to apply a judgement bias test to broiler chickens to assess level of optimism.

In swine. The US swine industry continues to struggle with mortality across all phases of production and research on environmental enrichment for boars and neonatal and nursery piglets are limited. Iowa State University will investigate different chemosensory stimuli applied to cotton ropes that will be provided to piglets from day 2 through 5 of lactation in one study and on biscuits attached to rope that will be provided to nursery piglets from day 0 through 6 post-weaning. Behavior and production performance will be collected in both studies. Research conducted at University of California Davis on individually-housed, mature boars found that the animals preferred interacting with hanging cotton rope enrichment over hanging rubber chew sticks when given the option (Sirovica et al., 2019). The boars spent less time performing the abnormal stereotypic behavior of sham chewing when provided enrichment as compared to no enrichment. Future research at University of California Davis will investigate the preference and impact of alternative enrichments (brushes, rubber mats) on boar and group-housed gestating sow welfare (lameness prevalence, social aggression, and performance of abnormal oral-nasal behaviors).

Adult minipigs are gaining popularity for biomedical research. They are preferred over commercial breeds because of their convenient size and some of their physical similarities to humans. However, these pigs must follow a strict, limited diet to prevent them from becoming obese. In addition, they appear to experience distress during the 12-18 hour food withdrawal period before anesthetizing them for imaging procedures, which confounds both behavioral and physiological outcomes. The USDA-ARS in Manhattan, KS, Kansas State, and University of Nebraska at Lincoln will evaluate if sorghum-based products can mitigate the effects of hunger on obese minipigs’ behavioral and neuroinflammatory responses during dietary restriction. During this research, pigs’ housing will be developed into a “smartpen.” Environmental enrichment use will be automatically collected for oral behaviors (nutritive and non-nutritive), grooming, laterality, and social approach-withdrawal temperament using a combination of sensors and University of Nebraska at Lincoln’s NuTrack system for monitoring individual behavior patterns.

In cattle. The University of Wisconsin-Madison and the University of Florida are partnering to investigate the use of stationary brushes by post-weaned dairy heifers. Dairy heifers are often housed in barren, confined housing after weaning. Simple brushes are used by heifers for self-grooming and oral manipulation. These objects represent a low-barrier solution to increase environmental complexity. We are evaluating how many brushes should be provided to group-housed heifers to allow free usage and minimize competition.

 

In horses. The University of Florida will investigate grazing, leisure, and active behaviors in horses managed on warm season grass pastures intercropped with legume forage (rhizoma peanut). Additionally, stabled horses’ feeding behavior and preferences when provided access to a variety of hay types including rhizoma peanut will be evaluated. Increased time spent feeding and providing horses with the opportunity to select between forages has the potential to promote normal foraging behavior and to improve horse welfare.

 

In fish. Virginia Tech is investigating the impact of enriched housing conditions on affective states in rainbow trout (Oncorhynchus mykiss). Fish farming is a common and sustainable method of contributing to the food market with over 35 million trout produced in the USA in 2018 alone. This project focuses on assessing the affective states through a judgement bias test in trout reared under different environmental complexities and under different stocking densities. They will assess whether complex housing environments and low stocking density correlate with affective states (optimistic versus pessimistic), stress, and production parameters.

 

In zoo animals. Often due to a lack of sensory or cognitive stimulation, captive animals in zoological facilities are prone to develop stereotypic behaviors, such as pacing in captive felids. Given the relevance of olfaction for captive felids, University of California Davis will investigate the preference and impact of olfactory enrichment among nine adult jaguars living in a central California facility. Objects will be sprayed with a natural (elk urine) or synthetic (perfume) odor. Identifying the odor preference for captive felids can help caretakers provide an appropriately stimulating environment to encourage species appropriate behavior.

Early development

In poultry. Aviary systems for laying hens provide greater behavioral freedom, but are associated with greater risks to hen respiratory health and problems with eggs being laid on the floor instead of in nests. Research at Purdue University will be conducted to examine behavioral indicators of hens’ use of flooring substrates for aviary systems and whether early experience with flooring substrates influences dustbathing and foraging behavior, as well as hen welfare parameters.

In horses. Early exercise of horses can have significant impacts on the development of the young horse’s musculoskeletal system. Research at Texas A&M University will examine indicators and biomarkers related to musculoskeletal injuries of horses, including the time course and concentrations of biomarkers in serum and synovial fluid and how early forced exercise and the type of exercise influences these biomarkers. This research will provide information about how early conditioning influences joint inflammation and turnover of cartilage and bone and will aid in identifying critical ages where changes to exercise protocols can have the largest effects on reducing risks for musculoskeletal injuries.

In cattle and sheep. Research has demonstrated the detrimental effects that housing animals in isolation can have on animal welfare, but information is still needed about the long-term effects that social housing and early social interactions can have on animal health, behavior and welfare. Researchers at the University of Wisconsin-Madison will examine how rearing dairy calves in pairs, rather than individually, influences responses to thermal stress and long-term effects on feed efficiency at breeding age. Research at Oregon State University will examine sensitive periods in the social development and impact of stress on sheep and companion animals.

In dairy calves, social housing is currently gaining in popularity. While early social contact provides a number of benefits related to social development (Costa et al., 2016), it creates the potential for competition for access to feed and other social stressors. The University of Florida will evaluate changes in social behavior, as assessed using social proximity and preference for social withdrawal, as an indicator of pain and disease in dairy calves. Social behavior will be measured using location tracking technology, to assess how proximity-based social networks may predict or indicate developing disease, and assess the use of pen features which accommodate visual and physical seclusion from penmates when calves are expected to be in pain. The University of Minnesota will investigate the association between play behavior in pre-weaned dairy calves (e.g. jumping) recorded using sensors and calf disease for calves housed individually, in pairs or small groups.

Iowa State University will evaluate feeding patterns and social behaviors of a sow herd transitioning from individually housed stalls to group housing to optimize facility design to improve feed efficiency and production. Collaborative work at Michigan State University will examine how feeding behavior in single-space electronic feeders is affected in finishing pigs by the presence and behavior of a second pig attempting to enter the feeder. The University of Oregon will use and adapt attachment methods/secure base effect methods to evaluate the relationship between social support, stress reduction and general wellbeing.

Social behavior, beyond early experience

In poultry. Michigan State University, will explore how the presence of conspecifics affects the behavior of laying hens on the litter area to understand influences of synchronicity, social facilitation, or desired distance from nearest neighbor influence space needs of non-caged laying hens.

In cattle. Texas A&M will investigate the impact of social mixing on the behavior, social network, dominance hierarchy establishment, and productivity of beef cattle. The utility of monitoring social behaviors to detect cattle with subclinical disease will be evaluated. In addition technologies will be tested for their ability to monitor social interactions. The impact of topical pheromones on weaning stress, and the impact of handling frequency on social behavior and reproductive development in beef cattle will also be investigated along with the relationships between social dominance and bull reproductive success and physiology.

Across species. University of California Davis will continue to investigate the relationship between the personality trait of "sociality" among group-living livestock (swine, cattle, sheep, and poultry), disease spread, and group cohesion [i.e., aggression, shared resources] via social network analyses.

Objective 2

This objective will be achieved by making progress with welfare assessment in specific sectors (cattle, pigs and poultry) and by improving tools to identify animals with compromised welfare on commercial farms. Understanding human perspectives is a key aspect to achieving this objective.

In dairy cattle. University of Kentucky and University of Minnesota will continue to evaluate outcome-based measures of welfare such as lameness, injury, mortality and disease incidence on commercial farms to determine benchmarks for improved welfare and provide guidelines for welfare assessments. University of Wisconsin-Madison and University California Davis will investigate sampling strategies and variables to measure for: (1) measures of normal and abnormal oral behaviors in pre-weaned dairy heifers, and (2) indicators of heat stress in dairy cows. These stations will also work together to create an online training program for identifying of compromised health in milk-fed dairy calves. University of Minnesota will set up a framework for integration of on farm data with hoof trimming data to allow for future studies to be conducted in a more streamlined manner. The future studies would correlate farm level locomotion score data to hoof lesion data.

Poultry welfare assessment

In chickens. University of California and Iowa State University will perform assessments of laying hen welfare on both small and large-scale cage-free commercial farms using a modified version of the Welfare Quality Assessment Protocol, combined with evaluation of producer records. The goal of these studies will be to determine the prevalence of problems that are of potentially highest concern: beak malformation/poor trimming; keel bone deviation and breakage; cannibalism; feather loss; foot problems; parasite infestation; disease; and mortality (and causes of mortality). An epidemiological approach will also be used to determine risks for these problems related to factors such as genetics, availability of outdoor access, organic management, pullet rearing methods, and housing configuration.

Texas A&M University will compare and contrast the National Chicken Council and the Welfare Quality welfare assessments for broiler chickens. These evaluations will be conducted on a commercial broiler breeder flock. Similarities and differences between the tools, their outcomes, and practicality of implementation will be evaluated.

In ducks. University of California Davis will conduct research to quantify the way in which duck welfare assessment sampling protocols and methodologies affect obtained outcomes. Specifically, this station will compare the transect walk method described by Marchewka et al., 2013 and 2015, with data collected using standard animal welfare assessment methodologies. The research will improve our understanding of the accuracy of the evaluated methods, and will provide insight into the way in which aspects of sampling protocols (ex. proportion of flock sampled, frequency of visits) affect the method’s validity and reliability.

In turkeys. The transect walk method for evaluating the welfare status of birds has shown to be practical, low-cost, easy to implement and reliable across observers. Although validity has to be established separately for each broilers and turkeys, University of California Davis’ most recent trial with turkeys has shown that results obtained using the transect method are similar to results obtained by individual evaluation of each bird in the flock (during load out). By using the transect method to evaluate the welfare of turkeys as part of our upcoming research, we will be able to further our understanding of the accuracy and practicality of this assessment method.

 Identifying animals with compromised welfare

In dairy cattle. University of Kentucky, Washington State University and University of Minnesota will investigate the application of precision dairy technologies such as cow behavior and temperature sensors to assess animal welfare at the group level and help dairy producers respond at the very first non-specific signs of imminent trouble. For example, there have been studies documenting that fresh cow disease is preceded by non-specific symptoms 5 to 10 days prior to the onset of specific clinical signs. Elevated core body temperature, reduced activity, drop in milk production, changes in feeding and resting behavior, and changes in milk composition are all signs that cows need attention. More research is needed on what can be done if/when a certain percentage of animals in a farm or group show signs of illness. The strategy would be to remove predisposing causes of sub-par performance or disease such as inadequate management practices or housing conditions. The outcome of this work will strength animal welfare assessment at the herd level by providing much-needed information about how electronic monitoring can be incorporated into herd management.

In pigs. Science-based guidance for pig producers on proper on-farm decision criteria for euthanasia in piglets is deficient. Scientific knowledge about the effects of various euthanasia methods on piglet and pig welfare is growing; nevertheless, the act of euthanasia on-farm involves a decision-making process from the stockperson, with the responsibility to perform the procedure itself. Equipping the stockperson with the most relevant and up-to-date knowledge that leads to good decision-making and skills to competently perform the procedure is crucial to avoid undesirable welfare outcomes. Research to address the limited knowledge in this area is essential in formulating science-based recommendations and tools to enhance on-farm euthanasia decisions and individual piglet welfare. The Ohio State and Iowa State Universities will identify quantitative and qualitative decision criteria for on-farm euthanasia of pigs. Based on these findings, they will develop educational material on timely decisions for euthanasia of pigs for employees. This information will also inform animal welfare audits, such as the Common Swine Industry Audit.

 

Understanding human perspectives

 

In order to ensure adoption of welfare assessment schemes on farm, it is important to involve the humans who are responsible for caring for animals, those who will be doing welfare assessments, and those who are making decisions regarding culling and euthanasia.

 

Surrounding use of technology. Research examining the perspectives of producers and stock people related to key welfare measures and tools, including technology, that could be used to assess welfare will be undertaken at several stations. Researchers at Michigan State University will survey pig producers and swine veterinarians and interview other stakeholders in the pork supply chain to understand how they feel about using precision livestock farming (PLF) technologies to manage and monitor pigs and what uses they envision for the resulting animal-based data. Pig farmers and veterinarians will specifically be asked about issues they perceive to be important to pig management and welfare before examining their awareness of specific types of technologies and exploring perceived barriers to adoption. Farmers will subsequently be asked how much they would be willing (or able) to pay to adopt PLF on their farms. Pork consumers in the US will also be surveyed to determine how much they would pay for pork products produced using PLF technologies and a choice experiment will be conducted to understand limitations to consumers’ ability to buy welfare-friendly pork products. Following these surveys, a cost-benefit analysis will be conducted to assess the economic viability of PLF technologies to improve the welfare of pigs on farm. Stakeholders and influencers involved with other aspects of the pork supply chain ranging from breeding and genetic improvement companies to welfare certification organizations to retailers will also be interviewed to gain a broader perspective of the potential ways PLF may be used or valued in the swine industry. PLF systems have the potential to provide actors across the pork supply chain with on farm data relevant to them, such as providing breeders with recording of novel phenotypes, certification schemes with indicators relevant to animal welfare assurances and retailers insights into compliance with particular standards. Realizing this requires PLF systems to be designed so that these varying needs can be met. Critically, however, little is known about these actors’ perceptions of PLF. For instance, it is unknown what types of outcomes these groups would like measured; whether their needs match capabilities of existing technologies; what barriers they perceive hinder the application of PLF in their respective operating contexts; whether they trust PLF data; and what expectations they have for PLF systems (e.g. the problems they expect them to solve). Information gained from these surveys and interviews will be shared with farmers, veterinarians and other pork industry stakeholders, including the project advisory board, to facilitate adoption and development of feasible and useful PLF technologies on farm.

 

On euthanasia. In addition to perspectives surrounding technology use, research is needed to understand perspectives surrounding animal euthanasia decisions. Research at Iowa State University will be conducted to examine whether training modules that are based on the Predictive Index (PI) Personality Assessment can reduce euthanasia-related strain in animal caretakers, leading to important animal welfare outcomes. Another project will examine attitudes, specifically of Spanish-speaking caretakers, to examine how caretaker attitudes influence the quality and appropriateness of timely euthanasia.

 

Promoting welfare assessment by law enforcement. The University of Florida team will continue their Livestock Education and Certification for Agriculture Law Enforcement (LECALE) Program to improve the ability of attendees to assess animal welfare (livestock and equine). This certification course combines classroom instruction and hands-on, live animal demonstrations and training exercises to increase attendee knowledge and experience in equine and cattle behavior and welfare.

 

In dairy cattle. Researchers and extension specialists from the University of Wisconsin-Madison, University of Tennessee-Knoxville, The Ohio State University, other international sites, including University of Melbourne (Australia), University of Prince Edward Island (Canada), and University of Helsinki (Finland) are collaborating on an interdisciplinary project including both biological- and social-science approaches to animal welfare. This project aims to build public trust in the dairy industry by engaging the public and dairy industry professionals. To promote positive interactions between humans and the animals under their care, this international team will develop and implement an evidence-based training program to modify the attitudes and behaviors of those working with dairy cows.

 

Researchers at the University of Florida will survey dairy producers in Florida to investigate current perspectives and implementation of practices aimed at improving the welfare of dairy calves. The particular emphasis of the team is to explore perception of key housing and nutritional management specific to dairy calves.

 

Washington State University researchers will investigate employee-cattle interactions on dairies. Workers’ Compensation claims from dairy employees show that the most common cause of injury is human-animal interactions. Improper cattle handling causes distress for the employee and the animal, often resulting in injuries. Surveys will be distributed to dairy producers and employees to learn how cattle handling training is provided on dairies and determine whether any specific handling training method correlates with lower employee injury incidence rates, as well as improved cattle well-being. By integrating data from Workers’ Compensation claims, dairy producer and employee perspectives, and dairy cattle behavior information, researchers at Washington State University will develop and distribute dairy cattle handling training tools that will make employee-cattle interactions safer, less stressful, and more efficient.

Measurement of Progress and Results

Outputs

• Publication of results in peer-reviewed manuscripts that will provide researchers and educators tools and information on how to assess animal welfare.
• Validation of science-based behavioral, physiological and disease measurements used to measure welfare under a range of sector-relevant contexts
• Development and/or validation of automated measures of welfare, including indicators of health and behavior.
• Input from farmers and other persons involved in animal care or production that can be used to better translate science into practices that improve welfare.

Outcomes or Projected Impacts

• The findings of this committee have the potential to impact the welfare of billions of agricultural animals as well as to increase the productivity and competitiveness of US producers.
• This project will provide science-based recommendations about provision of environmental enrichments across a range of conditions and species.
• The results from this project will provide science-based information about pain in cattle and pigs. These findings may facilitate treatment in production settings and establishment of efficacious analgesic drug regimens for various painful diseases or procedures.
• Development and/or validation of automated measures of welfare, including indicators of health and behavior will lead to uptake of these technologies in commercial situations.
• Deepen our understanding of human perspectives of technology, euthanasia and other management decisions.

Milestones

(2022):Revisit collaborations with USDA multistate reporting guidelines in mind; conduct, compile and analyze data from initial studies

(2023):Conduct planned studies using methods outlined above; apply for additional funding; prepare data for manuscripts and conference proceedings

(2024):Continue conducting planned studies; prepare data for manuscripts and conference proceedings

(2025):Continue conducting planned studies; prepare data for manuscripts and conference proceedings

(2026):Complete publications of findings To date, the NC-1029 has been a successful multi-state project and we have every reason to expect continued success. Applied animal behavior and animal welfare research is a relatively new scientific discipline in the US. Indeed, participation in this multi-state project doubled over the last five-year period, from 20 to 40. However, a challenge faced by researchers working in this area is the ability to have a critical mass of persons and resources in one central location and available funding to support welfare and behavior programs. One of the strong points of the NC-1029 is that it fosters collaborative research, therefore consolidating resources and effort. In addition, some members of the committee also hold teaching and/or extension appointments, allowing the information to be more easily disseminated to stakeholders of animal agriculture. Members of the NC-1029 conduct research with a variety of species and approaches, and therefore, the diversity of experience and skills is an asset. This group is currently at the forefront of behavior and welfare research in agricultural animals and members are frequently approached by industry groups with questions related to animal welfare. Ideas and approaches from newer members should further contribute to the development of novel methods to measure behavior and assess on farm animal welfare. The NC-1029 comprises the leading applied animal behavior and welfare researchers and teachers in the US and their wide-ranging skills are likely to yield significant progress in this area.

Projected Participation

View Appendix E: Participation

Outreach Plan

Various members of NC-1029 hold extension or outreach appointments and will contribute to dissemination of project findings to other researchers, producers, and specialized groups who are using this kind of practical information to assess the welfare of agricultural and captive animals. There are also many members involved in teaching activities so that the upcoming generation of researchers, industry and producers can be well informed about issues related to animal welfare.

Research scientists will be targeted through the International Society for Applied Ethology (ISAE), which is the international professional organization of scientists studying agricultural animal behavior, and appropriate scientific animal societies, such as American Society of Animal Science (ASAS), American Dairy Science Association (ADSA), American Association of Swine Veterinarians (AASV) and Poultry Science Association (PSA). The ISAE has a regular newsletter and an e-mail network that can be used to inform others about the research project. The final research results will be presented at the ISAE annual congress before an international audience and it is likely that Applied Animal Behavior Science, the official journal of the ISAE, would be a key peer-review journal where results would be published. Members of NC-1029 will also present research results at the ASAS, ADSA, and PSA annual meetings and publish in the journals of these societies.

Producers may be asked to review and comment on on-farm welfare assessment and audit programs for their particular species. Producers need to have some fundamental knowledge of the latest research results in these areas. In the US, outreach efforts will be led by the dissemination of information via the land-grant extension system as well as through the activities of each station. In general, members are well connected to many aspects of animal agriculture and often provide expert opinion for various industry groups, retailers and other stakeholders. For example, NC-1029 members serve in advisory capacities for companies in the supply chain (including Aldi, Sysco, 7-Eleven, S-Safe, Darden, Kraft Heinz, Cargill, Tyson, Leprino, Danone, Nestle Purina, Elanco, Foster Farms, Maple Leaf Farms), industry groups (National Milk Producers Federation, National Cattleman Beef Association, Veal Quality Assurance, United Egg Producers, Dairy Cattle Welfare Council), and specialty labelling programs (American Humane Association, Global Animal Partnership, Humane Farm Animal Care, Progressive Beef, FACTA). Service in these roles gives our members considerable influence and reach when disseminating our findings. Data generated from the current project will also be disseminated at producer meetings, posted on websites, and published in relevant newspapers and trade magazines. Social media will also be used to distribute or highlight key results.

Results will also be disseminated to those groups that are considering, or that are already conducting, on-farm welfare assessments or audits, such as some of the groups outlined above. It is important that those groups incorporate practical indicators of welfare and that they know the validity and reliability of those indicators.

In general, this project is expected to result in collaborative, peer-reviewed scientific publications and reviews, as well as abstracts presented at national and international meetings, and extension publications. This project also provides unique opportunities for interdisciplinary training of graduate students and other research personnel. Specifically, the updated 2020 USDA reporting guidelines for multistate project prioritize collaborative output over related work by individual participants. NC-1029 membership has doubled since its last renewal and emphasis on identifying productive collaborations that result in dissemination of information will be prioritized. This will be a key goal of the 2022 meetings of this group.

Organization/Governance

The Executive Committee of NC-1029 shall consist of the Chair and Secretary.

Chair: The chair of the committee is responsible for organizing the meeting agenda, conducting the meeting, preparing the final version of the annual report, and assuring that tasks and assignments are completed.

Secretary: The secretary is responsible for keeping records on decisions made at meetings (a.k.a. keeping the minutes) and assisting in the preparation of the annual report by collecting and combining station reports.

The Chair is elected for a 1-year term. The term of Office of the Chair will end at the adjournment of the regular annual meeting. The previous Secretary will become the Chair for 1 year. A new secretary will be elected each year by those attending the Committee meeting.

Members: Committee membership requires active participation and information exchange (including the submission of a station report) at the annual meetings. In addition to carrying out the agreed information exchange, project members are responsible for contributing to the ongoing progress of any committee activity, and communicating their accomplishments to the committee's members and their respective employing institutions. Regular attendance is vital for a committee to be successful. Therefore, members that do not attend the annual meeting or send a substitute 3 years in a row will be removed from the committee.

Literature Cited

Banerjee D, Daigle C, Biswas S and Siegford JM. 2012. Remote activity classification of hens using wireless body mounted sensors. Body Sensor Networks. 2012: 107-112.

 

Banerjee D, Daigle CL, Dong B, Wurtz K, Newberry RC, Siegford J and Biswas S. 2014. Detection of jumping and landing force in laying hens using wireless wearable sensors. Poultry Science. 93: 1-10.

 

Berg C and Raj M, 2015. A review of different stunning methods for poultry—animal welfare aspects (stunning methods for poultry). Animals. 5: 1207-1219.

 

Bikker JP, van Laar H, Rump P, Doorenbos J, van Meurs K, Griffioen GM and Dijkstra J. 2014. Technical note: Evaluation of an ear-attached movement sensor to record cow feeding behavior and activity. Journal of Dairy Science. 97: 2974-2979.

Brehme U, Stollberg U, Holz R and Schleusener T. 2007. ALT pedometer—New sensor-aided measurement system for improvement in oestrus detection. Computer and Electronics in Agriculture. 62: 73-80. doi:10.1016/j.compag.2007.08.014.

Brown-Brandl TM, Yanagi J, Xin H, Gates RS, Bucklin RA and Ross GS. 2003. A new telemetry system for measuring core body temperature in livestock and poultry. Applied Engineering in Agriculture. 19: 583-589.

Busse M, Schwerdtner W, Siebert R, Doernberg A, Kuntosch A, König B, and Bokelmann W. 2015. Analysis of animal monitoring technologies in Germany from an innovation system perspective. Agricultural Systems 138: 55-65.

Chapinal N, Barrientos AK, von Keyserlingk MAG, Galo E and Weary DM. 2012. Herd-level risk factors for lameness in freestalls farms in the northeastern United States and California. Journal of Dairy Science. 96: 318-328.

Chen C, Zhu W, Liu D, Steibel J, Siegford J, Wurtz K, Han J and Norton T. 2019. Detection of aggressive behaviours in pigs using a RealSense depth sensor. Computers and Electronics in Agriculture. 166: 105003.

Chen C, Zhu W, Steibel J, Siegford J, Han J and Norton T. 2020a. Classification of drinking and drinker-playing in pigs by a video-based deep learning method. Biosystems Engineering. 196: 1-14.

Chen C, Zhu W, Steibel J, Siegford J, Wurtz K, Han J and Norton T. 2020b. Recognition of aggressive episodes of pigs based on convolutional neural network and long short-term memory. Computers and Electronics in Agriculture. 169: 105116.

Chen C, Zhu W, Steibel J, Siegford J, Han J and Norton T. 2020c. Recognition of feeding behaviour of pigs and determination of feeding time of each pig by a video-based deep learning method. Computers and Electronics in Agriculture. 176: 105642.

Coetzee JF. 2011. A review of pain assessment techniques and pharmacological approaches to pain relief after bovine castration: Practical implications for cattle production within the United States. Applied Animal Behaviour Science. 135: 192-213.

Cohen S, Doyle WJ, Alper CM, Janicki-Deverts D and Turner RB. 2009. Sleep habits and susceptibility to the common cold. Archives of Internal Medicine. 169: 62-67.

Cook, NB. 2018. Assessment of cattle welfare: Common animal-based measures. Chapter 2 in Advances in Cattle Welfare, Tucker, CB, editor. Woodhead Publishing, UK.

Cooper MD, Arney DR and Phillips CJ. 2008. The effect of temporary deprivation of lying and feeding on the behaviour and production of lactating dairy cows. Animal. 2: 275-283.

Costa JHC, von Keyserlingk MAG and Weary DM. 2016. Invited review: Effects of group housing of dairy calves on behavior, cognition, performance, and health. Journal of Dairy Science. 99: 2453-2467.

Costa JHC, Cantor MC, Adderley NA, and Neave HW. 2019. Key animal welfare issues in commercially raised dairy calves: social environment, nutrition, and painful procedures. Canadian Journal of Animal Science. 99: 649-660.

Daigle C, Banerjee D, Biswas S and Siegford JM. 2012. Non-caged laying hens remain unflappable while wearing body-mounted sensors: levels of agonistic behaviors remain unchanged and resource use is not reduced after habituation. Poultry Science. 91: 2415-2423.

Daigle CL, Banerjee, D, Montgomery RA, Biswas, SK and Siegford JM. 2014. Moving GIS indoors: spatiotemporal analysis of agricultural animals. PLOS One. 9(e104002): 1-11.

de Lauwere C, van Asseldonk M, van ’t Riet J, de Hoop J, and ten Pierick E. 2012. Understanding farmers’ decisions with regard to animal welfare: the case of changing to group housing for pregnant sows. Livestock Science. 143: 151–161.

Eastwood C and Renwick A. 2020. Innovation uncertainty impacts the adoption of smarter farming approaches. Frontiers in Sustainable Food Systems 4: 24.

Eigenberg RA, Brown-Brandl TM and Nienaber JA. 2007. Sensors for dynamic physiological measurements. Computers and Electronics in Agriculture. doi:10.1016/j.compag.2007.08.011.

Ellen ED, van der Sluis M, Siegford J, Guzhva O, Toscano M, Bennewitz J, van der Zande L, van der Eijk J, de Haas EN, Norton T, Piette D, Tetens J, de Klerk B, Visser B and Rodenburg TB. 2019. Review of sensor technologies in animal breeding: phenotyping behaviors of laying hens to select against feather pecking. Animals. 9: 108.

Elischer MF, Arceo ME, Karcher EL and Siegford JM. 2013. Validating the accuracy of activity and rumination monitor data from dairy cows housed in a pasture-based automatic milking system. Journal of Dairy Science. 96: 6412-6422.

Elmore M, Garner J, Johnson A, Richert B and Pajor E. 2010. A flooring comparison: The impact of rubber mats on the health, behavior, and welfare of group-housed sows at breeding. Applied Animal Behaviour Science. 123: 7-15.

Endres MI, Lobeck-Luchterhand KM, Espejo LA and Tucker CB. 2014. Evaluation of the sample needed to accurately estimate outcome-based measurements of dairy welfare on farm. Journal of Dairy Science. 97: 35-23-3530.

Espejo LA and Endres MI. 2007. Herd-level risk factors for lameness in high-producing Holstein cows housed in freestall barns. Journal of Dairy Science. 90: 306-314.

Espejo LA, Endres MI and Salfer JA. 2006. Prevalence of lameness in high producing dairy cows housed in freestall barns. Journal of Dairy Science. 89: 3052-3058.

Gottlieb DJ, Punjabi NM, Newman AB, Resnick HE, Redline S, Baldwin CM and Nieto FJ 2005. Association of sleep time with diabetes mellitus and impaired glucose tolerance. Archives of Internal Medicine. 165: 863-867.

Grandner MA, Hale L, Moore M and Patel NP. 2010. Mortality associated with short sleep duration: the evidence, the possible mechanisms, and the future. Sleep Medicine Reviews. 14: 191-203.

Guarino M, Norton T, Berckmans D, Vranken E and Berckmans D. 2017. A blueprint for developing and applying precision livestock farming tools: A key output of the EU-PLF project. Animal Frontiers 7: 12-17..

 

Habing GG, Neuder LM, Raphael W, Piper-Youngs H and Kaneene JB. 2011. Efficacy of oral administration of a modified-live Salmonella Dublin vaccine in calves. Journal of the American Veterinary Medical Association. 238: 1184-1190.

 

Ison SH, Bates RO, Ernst CW, Steibel JP and Siegford JM. 2018. Housing, ease of handling and minimising inter-pig aggression at mixing for nursery to finishing pigs as reported in a survey of North American pork producers. Applied Animal Behaviour Science. 205: 159-166.

Ito K, von Keyserlingk MAG, LeBlanc SJ and Weary DM. 2010. Lying behavior as an indicator of lameness in dairy cows. Journal of Dairy Science. 93: 3553-3560.

Janczak, AM and Riber AB. Review of rearing-related factors affecting the welfare of laying hens. Poultry Science. 94: 1454-1469.

Karcher DM, Makagon MM, Fraley GS, and Lilburn MS. 2013. Influence of raised plastic floors compared with pine shaving litter on environment and Pekin duck condition. Poultry Science. 92: 583-590.

Lansade L, Bertrand M, Boivin X and Bouissou MF. 2004. Effects of handling at weaning on manageability and reactivity of foals. Applied Animal Behaviour Science. 87: 131–149.

Lay DC, Fulton RM, Hester PY, Karcher DM, Kjaer JB, Mench JA, Mullens BA, Newberry RC, Nicol CJ, O’Sullivan NP and Porter RE. 2011. Hen welfare in different housing systems. Poultry Science. 90: 278-94.

Ledgerwood DN, Winckler C and Tucker CB. 2010. Evaluation of data loggers, sampling intervals, and editing techniques for measuring the lying behavior of dairy cattle. Journal of Dairy Science. 93: 5129-5139.

Liboreiro DN, Machado KS, Basso Silva P, Barreto AE, Endres MI and Chebel RC. 2015. Characterization of peripartum rumination and activity of cows diagnosed with metabolic and uterine diseases. Journal of Dairy Science. 98: 6812-6827.

Lidfors, LM, Moran D, Jung J, Jensen P and Castren H. 1994. Behaviour at calving and choice of calving place in cattle kept in different environments. Applied Animal Behaviour Science. 42: 11-28.

Mantueffel, G., J. Langbein, and B. Puppe. 2009. From Operant learning to cognitive enrichment in farm animal housing: bases and applicability. Animal Welfare. 18: 89-95.

Marchewka, J, Watanabe TTN, Ferrante V and Estevez I. 2013. Welfare assessment in broiler farms: Transect walks versus individual scoring. Poultry Science. 92: 2588-2599.

Marchewka J, Estevez I, Vessoli G, Ferrante V and Makagon M. 2015. The transect method: a novel approach to on-farm welfare assessment of commercial turkeys Poultry Science. 94: 7-16.

Mench JA. 2008. Farm animal welfare in the USA: Farming practices, research, education, regulation, and assurance programs. Applied Animal Behaviour Science. 113: 298-312.

Millman ST, Duncan IJH, Stauffacher M and Stookey JM. 2004. The impact of applied ethologists and the International Society for Applied Ethology in improving animal welfare. Applied Animal Behaviour Science. 86: 299-311.

Morrow WM, Meyer RE, Roberts J and Lascelles D. 2006. Financial and welfare implications of immediately euthanizing compromised nursery pigs. Journal of Swine Health and Production. 14: 25-34.

Müller R and Schrader L. 2003. A new method to measure behavioural activity levels in dairy cows. Applied Animal Behaviour Science. 83: 247-258.

Munksgaard L, Jensen MB, Pedersen LJ, Hansen, SW and Matthews L. 2005. Quantifying behavioural priorities—effects of time constraints on behaviour of dairy cows, Bos taurus. Applied Animal Behaviour Science. 92: 3-14.

Munksgaard L and Simonsen HB. 1996. Behavioral and pituitary adrenal-axis responses of dairy cows to social isolation and deprivation of lying down. Journal of Animal Science. 74: 769-778.

Newberry RC. 1995. Environmental enrichment: Increasing the biological relevance of captive environments. Applied Animal Behavior Science. 44: 229-243.

Norton T and Berckmans D. 2018. Precision livestock farming: the future of livestock welfare monitoring and management? In: Animal Welfare in a Changing World. Butterworth, A (Ed). CAB International. Pp 130-144.

O’Driscoll KKM and Broom DM. 2011. Does access to open water affect the health of Pekin ducks (Anas platyrhynchos)? Applied Animal Behaviour Science. 90: 299-307.

Ontario Farm Animal Council. 2010. Caring for compromised pigs. Ontario Farm Animal Council. Accessed May 20, 2016. http://www.livestockwelfare.com/wp-content/uploads/Caring-for-Compromised-Pigs-July-2010.pdf

Opp MR. 2009. Sleep and psychoneuroimmunology. Immunology and Allergy Clinics of North America. 29: 295-307.

Peden RS, Camerlink I, Boyle LA, Akaichi F and Turner SP. 2019. Farmer perceptions of pig aggression compared to animal-based measures of fight outcome. Animals. 9(1): 22.

Peden RS, Turner SP, Boyle LA and Camerlink I. 2018. The translation of animal welfare research into practice: the case of mixing aggression between pigs. Applied Animal Behaviour Science. 204: 1-9.

Pépin D, Renaud PC and Decuq F. 2006. Identifying activity patterns from activity counters in ETHOSYS® collars on red deer. Applied Animal Behaviour Science. 96: 103-114.

Proudfoot KL, Weary DM and von Keyserlingk MAG. 2014a. Maternal isolation behavior of Holstein dairy cows kept indoors. Journal of Animal Science. 92: 277-281.

Proudfoot KL, Jensen MB, Weary DM and von Keyserlingk MAG. 2014b. Dairy cows seek isolation at calving and when ill. Journal of Dairy Science. 97: 2731-2739.

Quwaider M, Daigle CL, Biswas SK, Siegford JM and Swanson JC. 2010. Development of a wireless body-mounted sensor to monitor activity and location of laying hens in a non-cage housing system. Transactions of the American Society of Agricultural and Biological Engineers. 53: 1705-1713.

Riber AB, van de Weerd HA, de Jong IC and Steenfeldt S. 2018. Review of environmental enrichment for broiler chickens. Poultry Science. 97: 378-396.

Rodenburg TB, Tuyttens FA, Sonck B, De Reu K, Herman L and Zoons J. 2005. Welfare, health, and hygiene of laying hens housed in furnished cages and in alternative housing systems. Journal of Applied Animal Welfare Science. 8: 211-226.

Sabanayagam C and Shankar A. 2010. Sleep duration and cardiovascular disease: results from the National Health Interview Survey. Sleep. 33: 1037-1042.

Scheibe KM, Schleusner T, Berger A, Eichhorn K, Langbein J, Dal Zotto L and Streich WJ. 1998. ETHOSYS®--new system for recording and analysis of behaviour of free-ranging domestic animals and wildlife. Applied Animal Behaviour Science. 55: 195-211.

Scheier C. 2016. Egg industry sprinting to keep up with cage-free demand. Politico. Accessed May 20, 2016. http://www.politico.com/story/2016/03/egg-industry-fears-being-overrun-by-cage-free-demand-220249

Schirmann K, von Keyserlingk MAG, Weary DM, Veira DM and Heuwieser W. 2009. Technical note: Validation of a system for monitoring rumination in dairy cows. Journal of Dairy Science. 92: 6052-6055.

Shahid MQ, Reneau JK, Chester-Jones H, Chebel RC and Endres MI. 2015. Cow and herd level risk factors for on-farm mortality in Midwest US dairy herds. Journal of Dairy Science. 98: 4401-4414.

Shepherd M, Turner JA, Small B and Wheeler D. 2018. Priorities for science to overcome hurdles thwarting the full promise of the ‘digital agriculture’ revolution. Journal of the Science of Food and Agriculture. doi: 10.1002/jsfa.9346

Sirovica L, Creamer M, and Horback K. 2019. Preference for and behavioral response to environmental enrichment in a small population of sexually-mature, commercial boars. Animal Welfare. 28: 271-278.

Stafford KJ and Mellor DJ. 2011. Addressing the pain associated with disbudding and dehorning in cattle. Applied Animal Behaviour Science. 135: 226-231.

Stalder K, Lacy R, Cross T and Conaster G. 2003. Financial impact of average parity of culled females in a breed-to-wean swine operation using replacement gilt net present value analysis. Journal of Swine Health and Production. 11: 69-74.

Tactacan GB, Guenter W, Lewis NJ, Rodriguez-Lecompte JC and House JD. 2009. Performance and welfare of laying hens in conventional and enriched cages. Poultry Science. 88: 698-707.

Tauson R. 2005. Management and housing systems for layers–effects on welfare and production. World's Poultry Science Journal. 61: 477-490.

Thaxton YV. 2018. Gas and low atmospheric pressure stunning. In: Advances in Poultry Welfare. Mench, JA (Ed). Pp 101.

Tucker CB, Mintline E, Banuelos J, Walker KA, Hoar B, Varga A, Drake D and Weary DM. 2014. Pain sensitivity and healing of hot-iron cattle brands. Journal of Animal Science. 92: 5674-5682.

Rault JL, Holyoake T and Coleman G. 2017. Stockperson attitudes toward pig euthanasia. Journal of Animal Science. 95: 949-957.

Rutten CJ, Velthuis AGJ, Steeneveld W and Hogeveen H. 2013. Invited review: Sensors to support health management on dairy farms. Journal of Dairy Science. 96: 1928–1952.

USDA. 2008. Dairy 2007, Part III: Reference of dairy cattle health and management practices in the United States, 2007. USDA–APHIS–VS, CEAH. Fort Collins, CO. N482.0908:28.

Viscardi AV, Hunniford M, Lawlis P, Leach M and Turner PV. 2017. Development of a piglet grimace scale to evaluate piglet pain using facial expressions following castration and tail docking: A pilot study. Frontiers in Veterinary Science. 4:1–9.

Viscardi AV and Turner PV. 2018. Use of meloxicam or ketoprofen for piglet pain control following surgical castration. Frontiers in Veterinary Science. 5:299

Westin R, Vaughan A, de Passille AM, DeVries TJ, Pajor EA, Pellerin D, Siegford JM, Vasseur E and Rushen J. 2016. Lying times of lactating cows on dairy farms with automatic milking systems and the relation to lameness, leg lesions, and body condition score. Journal of Dairy Science 99: 551-561.

Wurtz K, Camerlink I, D’Eath RB, Peña Fernández A, Norton T, Steibel J and Siegford J. 2019. Recording behaviour of indoor-housed farm animals automatically using machine vision technology: A systematic review. PLOS ONE. 14(12): e0226669.

Attachments

Land Grant Participating States/Institutions

AL, AR, CA, FL, IA, IL, IN, MI, MN, MS, ND, NE, OR, SC, TN, TX, VA, VT, WI

Non Land Grant Participating States/Institutions

Spain, Tarleton State University, Texas Tech University, University of California, Davis