Duration: 10/01/2004 to 09/30/2009

Administrative Advisor(s):

NIFA Reps:

Non-Technical Summary

Statement of Issues and Justification

Over the last three decades, per capita consumption of poultry has steadily increased in the U.S. and globally. Improved poultry production systems have contributed to significantly enhanced performance traits (egg production, growth rates, meat yields, livability, feed conversion) and are responsible for providing economic, nutritious, and safe food choices. However, the poultry industry is increasingly challenged to address consumer and general public concerns about animal welfare and environmental issues. Pressure from well-intentioned groups using outdated, unscientific information, as well as misunderstandings of consumers removed from agriculture, have resulted in substantial redefinition of acceptable production practices. Tensions between optimal production (safe, affordable food), welfare of birds in production, and perceptions of consumers will likely continue and intensify in the near term; it is imperative that future production practices are based on sound science that includes a strong emphasis on bird physiology and behavioral indicators of well-being in optimum housing environments. This particular multi-state project is uniquely positioned to generate exactly the kind of information and knowledge needed to prevent costly restrictions on the poultry industry and at the same time to help the industry provide optimum and humane production conditions.

To optimize production, it is essential that important environmental conditions be well defined and that interactions among various components of the system be identified. Production optimization requires that the physiological basis for the bird's response to its complex environment be well understood. It also requires that the interactions between multiple environmental factors (thermal, gaseous, nutritional, social) and genetics be elucidated as well as the ways in which multiple environmental factors converge to disrupt physiological processes, resulting in, for example, ascites, respiratory impairment, skeletal deformations, reproductive failure, all of which have profound impacts on the poultry industry. A recent estimate of annual economic losses to the poultry industry because of heat stress related mortality and production decreases (all segments) is $125 to $165 million (St. Pierre et al., 2003). The deaths, in 1995, of layers in Iowa during a 2-wk heat wave amounted to ~$9 million in losses (Xin, 1998). The effects of heat stress on the poultry industry are thus not insignificant. In addition to substantial financial losses, these conditions compromise welfare and performance of individual birds. An interdisciplinary, collaborative approach to addressing these problems is essential because of the multifaceted nature of poultry production systems and the reciprocal and simultaneous effects on different aspects of performance or welfare.

The critical questions proposed as the focus of this project are as follows:
1) What physiological and behavioral parameters are disrupted by stress episodes of various types and durations, and how are they disrupted mechanistically?
2)Can the disruptions be prevented or reversed by environmental manipulations?
3)What management technologies are suggested by answering Questions 1 and 2?

Animal-environment interactions are complex. No environmental factor exerts its influence on animals in a vacuum, nor does any physiological response occur without affecting other systems. Increased sophistication of analytical and data processing methodologies, and greater precision of environmental control systems, increase the desirability of multi-disciplinary research efforts. In addition, research to address these complex interactions can be maximized when expertise is pooled and efforts are collaborative rather than isolated and individual. In times of tight budgets, sharing birds, facilities, and resources surely makes good sense, in that maximum return for dollars spent can be realized. Duplication of effort is minimized by crossing state and university lines to focus the tremendous scientific expertise of the committee members (physiologists, nutritionists, behaviorists, agricultural engineers, information systems analyst) of this unique multi-discipline, multi-state project on questions of critical importance to the poultry industry. In addition, a unique element of this project is the strong extension component. Many of the contributing members of the project have a primary extension appointment and thus are in direct and continual contact with poultry producers which facilitates the flow of information in both directions and strengthens the effectiveness of the project.

Although specific inter-state and university linkages will be indicated later in the proposal, some of the critical and unique instruments and facilities that will be shared/used collaboratively are spectral radiometers (CT) and audiology analysis systems (CT, NE), hypo/hyperbaric chambers (TX), emission chambers (IL), multi-channel telemetric body temperature sensing system with ingestible sensors (IA), infrared thermal imager for quantification of surface temperature distribution (IA), multi-station individual bird feeding units (IA), single-bird indirect calorimeters with infrared cameras and computerized data acquisition equipment and environmentally regulated production facilities for simulating field testing (NE, MD, MS(ARS)), environmental chambers for light control (CA), and four large-scale indirect animal calorimeters/emission chambers that allow for simulation of commercial production settings (IA). These are highly specialized pieces of equipment and/or facilities already in place that would be prohibitive to reproduce at other universities; collaborative use through this project maximizes both efficiency of use and research productivity. In addition, this project has the distinct advantage of behavioral expertise (CA, MD, NE) that is usually lacking in projects not specifically focused on behavior.

Successful completion of the endeavors outlined in this proposal will lead to 1) increased knowledge of basic physiological and behavioral processes in poultry; 2) identification of meaningful relationships between environmental factors and their associated production and economic ramifications; and, 3) enhanced management-decision making and action taking initiatives. With this information, housing environments can be optimized by defining environmental conditions (aerial, thermal, spectral, spatial, and nutritional) and management practices that will result in production systems which promote bird welfare and performance.

Related, Current and Previous Work

The Review of Critical Accomplishments from NE127 including publications resulting from this research and grants supporting the work is shown in an attachment.


CURRENT WORK: RESULTS OF THE CRIS SEARCH

A CRIS search on poultry environment identified only one other multi-state project working on similar areas, S-291 (Systems for Controlling Air Pollutant Emissions and Indoor Environments of Poultry, Swine and Dairy Facilities). While both the proposed research and S-291 share similar goals, S-291 has used an engineering approach to improve facilities in a variety of domestic animal species. In contrast, the proposed project will focus a diversity of disciplines on development of optimal environmental systems for broilers, chickens and turkeys, based on physiological and behavioral measurements.

The CRIS search also identified several other currently active research groups working in similar or related areas. Several citations were found but, as with S-291, the overlap was minimal and reflects different approaches to similar issues. Several stations were conducting measurements of air pollutant emissions from livestock and poultry facilities (GA (ARS), KY, and OH). MS (ARS) was correlating ventilation changes with broiler litter nitrogen and examining ammonia production of broilers reared in environmental chambers. MS, NC and PA are examining the use of dietary additives and strategies to reduce poultry manure nutrients. In contrast to the above work, the proposed research will be investigating environmental and dietary factors (including antibiotics) that could alter these emission rates. No other stations were found to be working in this specific area. AR (ARS) was identified as developing alternatives to the use of antibiotics from the standpoint of disease control. GA was examining the influence of antimicrobials on intestinal microflora.

Other aspects of the environment to be studied in this proposal will include light and acoustics. Other groups working in similar areas include AR (lighting studies in broiler breeders relative to hormonal control of reproduction); MD (ARS) (examining photoperiod and turkey hen breeder performance); and NY (bioacoustics of wildlife in navigating and orientation but not in agricultural animals). The proposed research will concentrate on poultry, specifically commercial meat birds and laying (chicken) hens. The area of acoustics relative to livestock and poultry is a very new area of research.

In the area of behavior and welfare, one Multi-state Project (NCR 131 Animal Behavior and Welfare) was found but a comparison was not possible as information was not available through the CRIS website. Related work in molting of laying hens is being examined at CA with emphasis on behaviors associated with different types of molting. NC is testing various molting programs with production, economic return and egg quality assessed. Other studies are concerned with reduction of Salmonella Enteriditis in molted flocks (GA (ARS), and TX). Beak trimming in laying hens is being examined at CA and IL. Ascites was studied by AK (ARS) using a hypobaric model to examine genetics and use of aspirin to reduce ascites and is currently emphasizing detection of genetic markers for use in future genetic selection. AR is currently finishing a project on methods to allow breeders to increase resistance to ascites in broiler lines.

While there may be some overlap between this project and some of those listed above, efforts should be viewed as highly complementary, with each having its own equally important uniqueness. None of the projects found in the CRIS search directly and completely overlap the work proposed by this committee.

CURRENT WORK: LITERATURE REVIEW

A. Defining and Measuring Animal Welfare

Animal welfare has been a controversial topic in animal agriculture because opinions differ regarding how animals should be maintained and treated. In part this is because some management practices that increase farm profitability may negatively impact welfare (e.g. increased stocking density) or fail to address behavioural needs (Broom and Johnson, 1993). Animal welfare, is a complex state which includes biological, psychological, and ethical components (Broom, 1986). The biological components can be further divided into physical, physiological and behavioral. Most of the physical components of welfare are easy to determine, as they include parameters traditionally used to evaluate performance and health (e.g. growth rate, body weight, comb color, and feathering condition) (Estevez et al., 1997; Estevez, 2002; Keeling et al., 2003). Behavioral indicators, such as occurrence of stereotypies, feather pecking, cannibalism, unusually high levels of aggression and social conflict, and duration of tonic immobility (Kostal and Savory, 1994; Bilcik et al., 1998; Gunnarsson et al., 1999) are considered excellent welfare indicators by ethologists. Physiological parameters, which include hormone levels such as corticosterone (Craig et al. 1986a), heart rate (Price and Sibly, 1993), or immune status (Gross and Siegel, 1983; Patterson and Siegel, 1998; Hecker et al., 2002) are also considered reliable indicators of the welfare status. High housing densities in poultry have been associated with increased mortality, and with reduction in bird performance (up to 7.6% higher mortality, and up to 24.4 fewer eggs at higher densities), reduction in feed intake, and increased corticosterone levels (Adams and Craig, 1985; Craig et al., 1986a and 1986b; Cunningham et al., 1987; Bell and Carey, 1998), all considered indicators of reduced welfare. The psychological component of welfare (how the animals "feel"; Duncan and Petherick, 1991), and the equally important ethical component (animals' "quality of life"; Duncan and Fraser, 1997) are responsible for much of the controversy because they are more vague, and can only be addressed scientifically through well-controlled experiments.

B. Elements of the Physical Environment

Thermal. High environmental temperatures (heat stress, HS) cause the loss of millions of dollars to the egg industry each year (Roland, 1988; Bell, 1998) due to reproductive failure (fewer eggs), poor egg quality (soft shells or shell-less eggs), and impaired skeletal integrity of the hen (Scott and Balnave, 1988). In poultry, in both laying and meat type birds, intensive genetic selection has resulted in tremendous improvements in traits such as egg production, egg size, internal and external egg quality, body size, feed efficiency, fertility indices, hatchability, etc. Negative correlations exist between many of these traits and susceptibility to heat stress, suggesting that selection for the production traits has adversely affected the ability to resist thermal challenge. A rise in environmental temperature above normothermia is considered to be one of the most serious problems for poultry operations. Of particular interest are HS-induced changes in acid-base status (Mather et al., 1980; Bottje and Harrison, 1986; Marder and Arad, 1989), ionized calcium (Odom et al., 1986), reproductive hormones (luteinizing hormone, progesterone) (Donoghue et al., 1989; Novero et al., 1991; estradiol - Mahmoud et al., 1996), and calcium uptake by duodenal cells in vitro (Mahmoud et al., 1996). Heat stress has been shown to decrease ionized calcium (Odom et al., 1986; Staten and Harrison, 1987) and all three reproductive hormones in blood. Forman et al. (1996) later confirmed by Hansen et al. (2004), in a preliminary study, found higher plasma estradiol and greater calcium transport in hens that had received exogenous estrogen prior to a 12h HS episode. Feeding high levels of vitamin D3 for an extended period (several months) at thermoneutrality improved calcium absorption in vitro (Novak, 1997) and in HS conditions (Franco, 2004). Heat stress reproductive failure in hens is quite well understood, but in the male it is less well known and changes are more subtle. However, both males and females rely on essentially the same biochemical mechanisms in the regulation of reproduction, though obviously to varying degrees, and one of these is a logical starting point for an investigation of genomic effects of heat stress. Ideally, to identify the point(s) at which heat stress affects gene expression in this common pathway would be a tremendous step forward in understanding how different genetic strains cope with HS and in identifying genetic markers for breeding programs.

Aerial. The volatilization of ammonia (NH3) from poultry manure can be a problem for the health of the birds (Anderson et al., 1964 Charles and Payne, 1966; Reece et al., 1980; Deaton et al., 1984; Al-Mashhadani and Beck, 1985), and has also become a cause of concern outside the poultry house. This environmental concern has recently forced regulatory agencies to enforce a daily limit of 100 lbs. of NH3 released to the atmosphere per house or farm (Patterson et al., 2002). Litter additives such as phosphoric acid (Malone, 1987), proprionic acid (Parkhurst et al., 1974), and ferrous sulfate (Huff et al., 1984) have been used to reduce the volatilization of NH3 from poultry manure. More recently, Kim and Patterson (2003) examined the use of minerals to reduce microbial urease activity of poultry manure. Commercially available, topically applied litter and manure amendments such as sodium bisulfate (PLT®), aluminum sulfate (Al+Clear®), and an enzyme treatment (De-oderase®) have been used with some success (Moore et al., 1995). Effectiveness of commercial products in reducing NH3 volatilization from poultry manure has been based on gaseous concentration of NH3 in and around poultry facilities; however, work at IL has shown that mass generation and emission rates have much more potential for establishing dosage and time interval effects of these compounds (Harrison and Koelkebeck 2001, 2002).

Visual. The value of regulating the photoperiod of poultry to stimulate reproduction has been recognized for many years and is used regularly by commercial poultry farmers. Many studies have proven the effectiveness of energy efficient compact fluorescent lamps for layers (Darre and Spandorf, 1985; Patterson and Darre, 2002, Widowski et al., 1992), and broilers (Zimmerman, 1988; Andrews and Zimmerman, 1990; Scheideler, 1990). Jarvis et al. (2002) studied the sensitivity of poultry to fluorescent flicker, reporting that chickens may perceive this phenomenon better than humans. Many studies have focused on the effects of quality or wavelength on performance (Harrison et al., 1969; Leeson and Summers, 1980; Leeson and Summers, 1985; Lewis and Morris 1998, 1999, 2000; Lewis et al., 2000; Pyrzak et al., 1986, 1987; Prayitno et al. 1997a, 1997b; Prescott and Wathes, 1999) showing that although birds respond to all wavelengths of light, broilers may be more active under red light than blue or green; they may grow slightly heavier under green lights whereas red appears to have a reproductive effect (Davis et al., 1999). Widowski et al. (1992) reported that laying hens show a preference for compact fluorescent lamps over incandescent lamps. Prayinto and Phillips (1997) conducted behavioral tests on pullets and found that chickens see red light (650 nm) as being equal in illumination to about three times the quantum flux of violet light (470 nm). Darre (1979) observed reduced agonistic behavior of chickens reared under red lights while Prescott and Waithes (2002) studied feeding behaviors under different illuminances. Fiber optics as a means of illuminating poultry needs study.

Auditory. Although much is known about hearing and sound production in poultry, we are still learning about the relationship of acoustical environments to their health and production. However, it is surmised that increased noise or the increase of certain tones and calls may significantly impact production. This has been shown regarding food calls in chickens where the presence of food was signaled to hens and where the food calls varied with food presence and food quality (Marler et al., 1986). It has also been shown that animal vocalizations correlate with handling and facilities design and as indicators of stress (Struwe, 1990) and even psychological well-being (Grandin et al., 1996 and Mulligan et al., 2003). Attempts are being made in California's poultry industry to use vocalizations of sentinel birds to signal disease outbreaks (G. Zeidler, personal communication). Further, current animal welfare regulations are tending toward the enactment of regulations and the institution of acoustic stress audits for animal welfare in the near future (Roybal, 2003). These issues will be affected by our knowledge (or lack thereof) of the effects of sound on animals as well our knowledge of animal hearing in the near future.

Spatial. Because most animals in production are kept under some degree of spatial restriction, it has been the focus of considerable research - how animals use the space, the effects on behavior and welfare, and interactions among varying densities of animals within the space (e.g. Hughes, 1977; Dawkins, 1983b; Doyen and Zayan, 1984; Lagadic and Faure, 1987; Roush et al., 1989; Roush and Cravener, 1990 for laying hens; Newberry and Hall, 1990, Estevez et al. 1997 for broilers). Changes in variation on use of space seems to be more affected by the relative animal density than by the number of birds in a pen (Freed and Estevez, 2002).

Multi-system Effects. Pulmonary hypertension syndrome (PHS) is recognized as a disease of multifactorial etiology leading to congestive right sided heart failure and death. Almost certainly a result of genetic (growth rate, Julian et al., 1986; 1989); metabolic rate; and/or environmental factors (Cueva et al., 1974; Julian et al., 1986, 1989; Lopez, 1989; Odom et al., 1995), PHS has been extensively characterized by cardiovascular changes such as reduced plasticity of erythrocytes (Mirsalimi et al., 1992); right ventricle hypertrophy (Burton and Smith, 1967; Maxwell et al., 1986, 1987; Julian, 1993; Odom, 1993; Odom et al., 1991, 1992, 1995, 1996; Martinez-Lemus et al., 1997, 1998, 1999, 2000; Wideman, 2000): and an increased plasma viscosity (Maxwell et al., 1992; Fedde and Wideman, 1996). L-arginine supplementation at a higher concentration than required for adequate growth, reduces the incidence of PHS in broilers (Wideman et al., 1995; Wideman, 2000). It is also an important limiting factor for endothelium-derived nitric oxide (Palmer et al., 1988; Eddahibi et al., 1992; Imaizumi et al., 1992), which plays a key role in regulating cardiovascular function (Palmer et al., 1987; Palmer et al., 1988). The activity of the vascular endothelium and smooth muscle in this commercially important cardiopulmonary circulation disease remains to be completely established.

C. Management Practices (Molting, Beak Trimming, Antibiotic Use)

A number of management practices have recently come under scrutiny by consumers and animal rights groups as unduly stressful to birds in commercial production, with molting and beak trimming among the most heavily criticized. As management practices, however, they are considered necessary, and the goal is to find ways to minimize discomfort or provide evidence that the impacts on birds are less severe than some believe. In addition, consumer objection to the use of antibiotics in animal feeds is increasing; a major challenge will be to find alternatives to antibiotics that confer the same degree of overall benefit to the birds.

Molting. Induced molting of laying hens is a practice used to extend the productive life of hens that varies in length of feed withdrawal and type of recovery diet used (Castanon et al., 1990; Koelkebeck et al., 1991; 1992; 1993a, b; 1999; 2001; Christmas et al., 1985; Brake and Carey, 1983; Ingram and Mather, 1988; Ruszler, 1996). Recently, concerns have been raised by animal rights groups and others that withdrawal of feed to induce a molt is harmful and stressful (Beuving and Vonder, 1977), or frustrating (Duncan and Wood-Gush, 1971), and negatively affects the welfare of the hen (Akin, 2000). In contrast, Webster (2000) found that feed withdrawal to induce molting in hens did not negatively affect their welfare as assessed by behavioral analysis. A number of studies have induced molting without feed withdrawal, using low-sodium diets (Nesbeth et al., 1976; Ross and Herrick, 1981; Naber et al., 1984; Whitehead and Shannon, 1974; Scheideler et al., 2003);high zinc diets (Berry and Brake, 1987; McCormick and Cunningham, 1984; 1987); guar meal (Zimmerman et al., 1987): and grape pomace (Kschavarz and Quimby, 2002); which demonstrate that positive post-molt performance can be achieved without feed withdrawal. More recently, Koelkebeck et al. (2003) found that low-energy diets, such as wheat middlings, provided good post-molt performance with no harmful effects on the hen?s physiological and behavioral status.

Beak Trimming. Cunningham (1992) in a review of beak trimming of chickens reached the following conclusions: beak trimming (correctly done) was effective in reducing mortality in flocks while having little or no effect on other production parameters. In turkeys, only a limited amount of published research on effects of beak trimming on production is available, though improvements in feed conversion have been shown (Cunningham et al., 1992; Noble et al., 1994; Noble and Nestor, 1997) and Denbow et al. (1984) found reduced mortality in beak-trimmed males. Despite reductions in mortality, concerns have been expressed about birds experiencing pain associated with the actual process and/or lasting discomfort (Cunningham, 1992). Gentle and co-workers (Gentle et al., 1982; Gentle, 1986; Gentle and Breward, 1986; Gentle et al., 1990; Hughes and Gentle, 1995) concluded based on the anatomy of the beak and changes in behavior after trimming that it is painful and results in long lasting effects on feeding behavior. Gentle et al. (1982) found that beak trimmed chickens were less efficient in grasping pellets compared to mash after trimming thus requiring more pecking activity to ingest an equivalent amount of feed. Recent work by Persyn et al. (2004) confirmed this finding and further characterized feeding behavior of laying hen with or without beak trimming.

Antibiotic Use. The initial discovery that dietary antibiotics, included at subtherapeutic levels as antibiotic growth promotants (AGP) (Rosen, 1996), improved poultry performance (weight and feed efficiency) occurred over 50 years ago (Jones and Ricke, 2003). Recently, concerns about potential contributions of AGPs to the development of resistant bacteria have led to increasing restrictions or bans of dietary AGP for poultry feed. The large number of physiological, nutritional and metabolic effects attributed to AGP's (Gaskins et al., 2002) will make it difficult to develop alternative nutritional and/or management strategies to replace their broadly beneficial effects (Joerger, 2003; Klein-Hessling, 2001; Ricke, 2003; Verstegen and Williams, 2002). In addition, no research has been conducted on the effects of AGP on manure characteristics including NH3 release potential and bacterial composition. Other than a report that probiotics (an AGP replacement) influence NH3 release and urease activity (Chiang and Hsieh, 1995), there are no reports examining AGP and NH3 release, and there is not much information on the influence of AGPs on overall metabolic efficiency in growing poultry.

D. Decision Analysis

Numerous environmental factors and resulting outputs can be effectively evaluated within the framework of a decision tree, based on previous decision analysis research (Roush et al., 1984, 1989; Roush, 1986; Roush and Cravener, 1992). This approach enables optimal decisions based on the controllable and uncontrollable states of the management system. Research by NE127 has provided most of the literature in this area.

Objectives

1. Characterize physiological, behavioral and performance responses of poultry to their physical and social environments and to various management practices, with the ultimate goal of enhancing animal welfare and ensuring environmental soundness while maintaining viable production profitability
   

Methods

Sub-objective 1. Characterize physiological and behavioral responses of poultry to critical elements of the physical environment (Thermal, Aerial, Visual, Auditory, Spatial, Multi-system) A. Thermal Environment Heat stress is a major economic factor for both egg and meat type birds and remains a focus of study by the committee. Egg production in layers, fertility in breeders, and nutrient utilization and growth in meat-type birds, are all negatively affected by exposure to abrupt onset of high environmental temperatures. Based on studies conducted under NE127, new questions have been identified as critical to the next generation of research endeavors to move the understanding of heat stress effects to a new level. A committee approach here takes advantage of availability of facilities and equipment at certain locations (CT, IL, IA), expertise across species including layers (NE), turkeys (MN) and broilers (MS(ARS)), and the various disciplinary expertise (physiology, NE; nutrition, DE; and engineering, IA). No one station could complete all facets of the proposed research. 1. Physiological Response Characterizations a. Handling Simulations (Collaboration between IA, NE, IL). Acute heat change such as that which may occur following removal of broilers from environmentally controlled housing for transport will be examined for physiological responses relative to gut fill, stocking densities, and duration and magnitude of heat change in environmentally controlled chambers and under simulated field conditions. b. THV-Index for Late Stage Turkeys (Collaboration between MN, IA; IA, NE). Commercial late stage meat turkeys will be subjected (MN, IA) to various combinations of air temperature, humidity and air velocity for 2 to 6 hours. Physiological measurements (IA, NE) will include internal body temperature, surface temperature, respiratory rate, and mortality. Data will be used to calculate THV-I as described subsequently. c. Fertility in Male Breeders (Collaboration between MD, NE and MS(ARS)). Specific endocrine and enzymatic factors involved in testosterone production of male broiler breeders during HS will be investigated at NE, and methods to alleviate effects and improve fertility will be developed at MS (ARS) and NE; evaluation of mating behavior as affected by HS will be conducted between MD and NE. Following acute heat stress episodes, sperm quality indices will be constructed, and blood and testicular samples will be assayed for testosterone and 3-beta-hydroxysteroid dehydrogenase. Candidate up-stream genomic factors will be investigated as possible candidates for genetic separation of heat stress susceptibility. d. Genetics of HS Resistance (Collaboration between NE and MS(ARS). In previous comparisons of three widely used commercial laying hen varieties (Hy-Line W36, W98, Browns) (NE), one strain (W98) consistently outperforms the other two during HS episodes with regard to production and endocrine factors. The research conducted in this study will focus on specific endocrine factors and enzymes (NE) involved in progesterone and estrogen synthesis. Samples will be collected over time and time to recovery after HS tracked. Data will be sent to MS (ARS) for analysis using statistical techniques for detecting patterns and establishing predictive equations and for inclusion into decision tree programs. 2. Dietary Manipulations and Susceptibility to Heat Stress a. Phosphorus (Collaboration between MS(ARS), DE, CT, NE). Dietary levels of phosphorus (P) appear to play a role in the bird's response to heat stress. It is proposed to study P utilization relative to susceptibility to heat stress in broilers. Initial studies will focus on dietary levels of inorganic P with the addition of phytase and heat stress-induced physiological responses. MS(ARS) and DE will be responsible for subjecting birds to HS (95-100F). CT will provide telemetric instrumentation for non-invasive monitoring of heart rate, respiration rate, and body temperature. Blood-gases and heterophyl:lymphocyte ratios (stress indicator) will be assessed by NE, and feed and fecal P will be analyzed at DE. b. Vitamin D3 (Collaboration between NE, DE). Two recent studies at NE have shown that high levels (22,000IU/kg) of Vitamin D3 fed for two weeks prior to an acute HS episode improve a number of parameters in laying hens (Franco, 2004). Because this amount of Vitamin D3 is generally considered to be in a range approaching toxic and because the responses were so unexpected, further research is warranted to determine mechanism of action and to further refine time of feeding relative to onset of HS. A series of studies is planned, in which White Leghorn laying hens will be given feed containing the excess vitamin levels for various time periods prior to onset of HS. Initially, the optimum feeding time by performance improvement relationship will be determined. Based on these results, further studies will be designed to probe for physiological mechanisms affected by the dietary treatment. B. Aerial Environment The volatilization of ammonia (NH3) from poultry manure is a major problem for the health of birds and caretakers. Concern from environmental groups and government has created a significant need to determine the extent to which NH3 emissions can be reduced by litter amendments, dietary manipulation or by other means. An important piece of this proposed research is the utilization of three emission calorimeters (EC) that have been developed by IL to evaluate mass generation and utilization of gases from materials inside the EC. NH3 concentration is read directly from analysis reaction tubes and is calibrated against two separate standard gases. This system can accurately measure NH3 emission from any manure source within the calorimeters. The other participating stations will be providing samples to IL for testing in the calorimeters. 1. Litter Amendments (Collaboration between AR, IA, MI, MN, and MD). The efficacy of various litter amendments on the reduction of NH3 from poultry manure will be investigated. Samples of poultry manure from in-house, manure storage, and composting units from layer (IA), turkey (MI, MN), and broiler (MD) complexes will be analyzed for NH3 emissions release as affected by application rates, concentration, and frequency of application of NH3 reducing compounds. The litter amendment products to be tested will be all those that are available commercially. Correlation of field data will be compared to baseline data obtained for samples tested in IL calorimeters. 2. Application of Compounds and Exhaust Scrubber Efficacy (Collaboration between MN, MD, MI, IA, IL). Alternative methods of reducing NH3 will be investigated at MN and MD as well as investigation of NH3 removal at IA by poultry house exhaust scrubbers. MI and MN will assess the effect of modifying the nutritional composition (protein and amino acid balance) of diets fed to turkeys and layers on baseline NH3 emissions of manure samples sent to IL for analysis. C. Visual Optimizing the photic environment of confinement reared poultry using energy efficient lighting devices will improve the welfare of the birds by reducing nervousness, decreasing agonistic behaviors and improve their feed efficiency. It is accepted that lighting intensity and spectral quality affect behavior in terms of aggression, laying and growth rates. By setting these parameters in accordance with the needs of the birds, it should be possible to improve the welfare of poultry in growing and layer houses and improve production. 1. Lighting Manipulations (Collaboration among CA, CT and NE) will cooperate on research with both meat type and egg type chickens using different lighting programs, including altering the photoperiod, using electronic lamps, LED's and fiber optics. Egg production, growth rate, feed efficiency, skeletal development, behavioral activity, and vocalizations as potential indicators of welfare and stress will be measured, recorded and analyzed. Economics of the systems tested will be calculated, including costs of installation, replacement and energy usage. D. Auditory Research on noise levels in modern animal agriculture needs to be updated relative to its effects on bird welfare. Although much is known about animal vocalizations as an indicator of welfare, vocalization intensity relative to environmental noise needs further study.. Damage risk criteria for decibel levels associated with various environmental and management conditions will be developed for poultry and subsequently used to develop appropriate welfare and handling guidelines and regulations. 1. Auditory Thresholds (Collaboration between CT, IA, MD, and MS(ARS)). Hearing thresholds will be determined in modern commercial strains of poultry using behavioral and electrophysiological methods. The best way to assess noise levels at which damage to auditory structures occurs is electrophysiologically using Auditory Brainstem Response methodology. In addition, testing of various poultry facilities will be required, to establish average noise levels from which impacts on bird stress and unit production may be established. The data will also be used to develop abatement measures and to formulate enrichment measures to reduce stress and increase production in the unit. 2. Vocalizations as a Welfare Assessment Tool (Collaboration between CT, NE, MD and MS(ARS)). Through the use of computerized vocal classification such as Artificial Neural Network, Hidden Markhov and Learning Vector Quantization models, vocalization types can be sorted into stress and non-stress classes. These vocalization classifications can be used in poultry units to monitor for the physical and psychological well-being. This would give operators a way of maintaining birds with minimal stress and to identify health problems early on. When used with the audiological information the two may provide a sound basis for animal welfare regulation and increased unit production. E. Spatial Spatial confinement imposes behavioral restrictions on poultry because of limitations in movement and use of space. Group size variations, high animal densities, and social factors may exacerbate these effects. A better understanding of space use by poultry will permit us to design facilities that best adjust to their biological requirements and hence, maximize their welfare. 1. Space Use Analyses (Collaboration between MI and MD). Space requirements and use by broilers and white pheasants will be studied in production settings. MD will continue to work on the effects of the physical (i.e. resource distribution) and social environment (i.e. group size and rearing densities) on social dynamics and use of space of broilers and layers. Particular emphasis will be given within the scope of this project to the development of new statistical spatial methodology to determine centers of activity and space requirements for poultry. F. Multi-system Effects Multiple environmental and genetic factors converge to cause the pulmonary hypertension syndrome, Ascites, in broiler chickens. 1. Nitric Oxide and Ascites (Collaboration between TX and AR). The mechanisms of action of NO on cardiopulmonary function as a component of the physiological adaptation of the cardiovascular system to environmental stressors will be the focus of initial studies. TX will further investigate important controls that play a role in pulmonary hypertension and pulmonary hypertension syndrome (ascites syndrome and sudden death syndrome). TX will use in vivo, in vitro, and cell culture methods to evaluate vascular responses that will correct the abnormal function of the cardiopulmonary circulation. The technique of Hess et al. (1996) will be modified to record pulmonary arterial pressure in freely moving chickens in barometric chambers subject to simulated high altitudes. Sub-objective 2. Characterize physiological and behavioral responses of poultry to critical management practices currently considered essential and beneficial to humane production (Beak trimming, Induced molt, Phase feeding, Antibiotic use) A. Beak/Bill Trimming and Induced Molt Beak trimming of poultry, induced molting of laying hens, and phase feeding have come under increased scrutiny because of pressure from animal rights organizations to ban such practices. These practices have been used for a long time in the industry but need further examination in the context of animal welfare, in order to defend them appropriately or to develop alternatives if necessary. The expertise provided by different members of the committee are critical to the completion of the project, especially that being provided by the behaviorists at CA, MD and NE and use of facilities and equipment at IA, DE, MN, and IL. Species expertise will be provided by MN for turkeys, CA for ducks, DE and MD for broilers, and NE and IL for chicken egg laying hens. 1. Beak trimming (Collaboration between CA, IA, MN, DE and MD). The effect of various beak trimming methods will be investigated in turkeys, ducks and chickens with respect to feeding and social behavior and subsequent production performance. Birds will be beak trimmed in IA (layers), CA (ducks), DE (broilers) and MN (turkeys) using several different commercially available methods. Behavioral parameters associated with diet form (pellets, mash), meal size, duration, ingestion rate and interval will be analyzed, with expertise provided by MD, as well as pecking, aggressive, and other behaviors. Production performance parameters (growth rate, feed efficiency, mortality, and carcass composition) will also be analyzed. 2. Induced Molt (Collaboration between IL, NE, and MD). Studies will be designed around the use of commercially available and economical feed ingredients in conjunction with photoperiod reduction to induce molting response. IL will assess post-molt performance, with behavioral analysis provided by MD and with hormonal assessment by NE. In addition, NE will consider alternative endocrine disruptors as a means of achieving reproductive quiescence. 3. Phase-feeding (Collaboration between MS(ARS) and MN). The supply and timing of proper amounts of feed and water impacts the welfare of poultry. For example, preliminary experiments (Vandegrift et al., 2003) have suggested that optimal phase feeding of poultry has a beneficial effect on the uniformity of a flock. Research at MS(ARS) will investigate, through advanced experimental designs (e.g., response surface and mixture designs), optimal conditions for the proper feeding of modern strains of poultry. B. Antibiotics in Poultry Diets Use of subtherapeutic amounts of antibiotics as growth promotants in poultry diets in the U.S. and other countries is under scrutiny by consumers and regulatory agencies. In several European countries, concern has risen to the point that these substances have been or soon will be banned. Termination of antibiotic use as growth promotant has been promulgated without substantial scientific evidence, and has not taken into consideration the impact on poultry welfare or on the environment. Bird heat production and litter characteristics could change as a result antibiotic removal from feed. Microbial populations in the gut and excreta may also be altered, leading to increased prevalence of bacterial pathogen-related disease. The impact of eliminating subtherapeutic amounts of antibiotics must be examined to determine the extent to which antibiotics affect nutrient and energy metabolism, to assess of the fate of the antibiotics in the environment after passage through the gut, and, to detect alterations in litter characteristics relative to NH3 release. 1. Antibiotics, Metabolism, and the Environment (Collaboration between MI, MN, NE, MD, IL). The influence of diet antibiotics, ingredients and fiber on nutrient and energy metabolism will be assessed. Broiler chicks will be fed diets formulated by MI/MN with and without antibiotic supplementation and placed into calorimeters at 3 and 6 weeks at NE for the determination of efficiency of energy utilization. Mass balance will be determined with analyses of carcass, feed, and excreta by MD, MI and MN. Samples of litter (excreta and bedding) and of both ground and well water from industry production environments will be collected by MI and MD and submitted for detection and assay of specific antibiotics. Antibiotic susceptibility patterns will be performed on enterococci isolated from similar samples from the same environments by MD. Samples of litter and manure from the above protocols will be submitted to IL for determination of NH3 emissions and to MD for determination of microbial composition. Samples will be tested as received and with treatment with litter additives. MD will conduct analyses to assess microbial composition. Sub-objective 3: Develop a decision support system based on characterization of responses in Sub-objectives 1 and 2, to optimize production and economic outputs while enhancing welfare of commercial poultry. Poultry managers are interested in the predictability of biological performance and uniformity of responses. Performance and uniformity are dependent on stochastic environmental conditions. The environmental components involved in poultry management systems are not independent; a change in one environmental component affects the status of the other components, resulting in changes in biological responses and in economic returns of the flock. For example, variations in the thermal environment can affect the feeding system requirements and vice versa. The change in management conditions ultimately affects the biological and economic performance of poultry. A. Decision Support and Predictive Economic Models (Collaboration among all participating universities; lead supplied by MS(ARS), IL and MD) Data collected in Sub-objectives 1 and 2 will be used to develop a decision support system (MS(ARS)) incorporating mathematical models (MD, IL) and management science optimization (IL, MD). For the NH3 emissions model, physical factors such as ventilation rate, litter pH, chamber temperature, humidity, and litter moisture will be used to confirm a previously developed model (Carr et al., 1987) and will be modified to include performance responses. MD will provide the lead for this model. Economic analyses will be applied to assess the economic implications of the environmental responses.

Measurement of Progress and Results

Outputs

• Physiological and behavioral responses of various poultry to thermal, aerial, resource distribution and other aspects of the physical and social environment will be determined.
• Analysis and interpretation of data in combination with economic decision analyses will provide recommendations to improve environmental conditions in poultry production.
• The data will provide an understanding for the basis of responses to thermal and other environmental conditions and if a genetic component exists for resistance to heat stress.
• Ammonia emissions models and indexes based on temperature and humidity will be developed from the collected data.
• More accurate quantitative measures of impacts of enviroment on poultry production and of poultry production on the environment

Outcomes or Projected Impacts

• An enhanced ability to predict stress effects of various environments with direct benefit to the welfare of the birds and sustainability for producers
• Thermal, space and aerial results will allow improved facility design and management of poultry houses to improve ventilation during both winter and summer seasons
• Identify the most important factors affecting ammonia release, which can then serve as control points.
• Science-based, economically sound recommendations relative to current management practices such as molting, bird density and beak-trimming
• Design of nutritional programs for heat stress conditions

Milestones

(2005): Modify telemetry methodology in 2005 for use in proposed thermal studies

(2006): Conduct preliminary work to examine genomic aspects of heat resistance

(2005): Begin acoustical work

(2005): Develop adequate statistical methods to determine minimal spatial requirements for poultry

Projected Participation

View Appendix E: Participation

Outreach Plan

Work completed will be disseminated in a number of ways: referred publications, presentations at scientific meetings, presentations at industry conferences, and publications in industry magazines and newsletters. In addition summaries of the completed work will be available at the project website and faculty will be encouraged to post information on their own web pages. Workshops could be organized around different aspects of the committee's work, such as a poultry ventilation workshop.

Organization/Governance

The Technical Committee is responsible for the planning and supervision of the MultiState Research Project. The membership of this committee shall consist of an Administrative Advisor, a technical representative of each participating agency or experiment station, and representative of the USDA Cooperative States Research Service. Each participating agency or experiment station is entitled to one vote. The Technical Committee shall be responsible for review and acceptance of contributing projects, preparation of reviews, modification of the regional project proposal, and preparation of an annual report. Annual written reports will be prepared by each technical committee member and distributed at the annual meeting. Annual reports will be complied and distributed to Technical Committee members and Agricultural Experiment Station Directors. The Technical Committee will meet yearly and conduct an election for the office of Junior Executive. The position will alternate between Poultry Scientists and Agricultural Engineers. In odd numbered years Poultry Scientist(s) will be nominated; in even number years Agricultural Engineer(s) will be nominated. The person elected to serve as Junior Executive will rotate through the remaining offices of Senior Executive, Secretary and finally serving as Chair in the fourth year. All voting members of the Technical Committee are eligible for office. The Chair prepares the meeting agenda and presides at meetings. The Chair is responsible for preparation of the annual report. The Secretary records minutes and assists the Chair. The Senior and Junior executives help with policy decisions and nominations. The Technical Committee functions as a unit with sub-committees formed as necessary. i.e., preparing nominations for elections.

Literature Cited

Adams, A.W. and Craig, J.V. (1985). Effect of crowding and cage shape on productivity and profitability of caged layers: a survey. Poultry Sci., 64:238-242.

Adnot, S.B. Raffestin, S. Eddahibi, P. Brquet, and P. Chabrier. 1991. Loss of endothelium-dependent relaxant activity in pulmonary circulation of rats exposed to chronic hypoxia. J. Clin. Invest. 87:155-162.

Akin, C. 2000. Email interview response to philosophy questions on fasting. Response is on the behalf of I. Newkirk, President of PETA, December 20.

Anderson, D.P., C.W. Beard, and R.P. Hanson. 1964. The adverse effects of ammonia on chickens including resistance to infection with Newcastle Disease virus. Avian Dis. 8:369-379.

Bell, D. 1998. Egg shell quality: its impact on production, processing and marketing economics. In: Passport to the Year 2000. Biotechnology and the feed industry. Proceedings of Alltech?s 14th Annual Symposium. T. P. Lyons and K. A. Jacques, Eds. Knottingham University Press. pp. 447-466.

Bell, D. and Carey, J. 1998. The effects of cage shape, housing and strain of chickens on various performance parameters (report #2). Progress in Poultry, vol. 37

Berry, W.D., and J. Brake. 1987. Postmolt performance of laying hens molted by high dietary zinc, low dietary sodium, and fasting: Egg production and eggshell quality. Poultry Sci. 66:218-226.

Beuving, G., and G.M.A. Vonder. 1977. Daily rhythm of corticosterone in laying hens and the influence of egg laying. J. Reprod. Fert. 51:169-173.

Biggs, P.E., M.W. Douglas, K.W. Koelkebeck, and C.M. Parsons. 2003. Evaluation of non-feed removal methods for molting programs. Poult. Sci. 82:749-753.

Bilcik, B., Keeling L.J. and Newberry, R.C. (1998). Effect of group size on tonic immobility in laying hens. Beh. Proc., 43:53-59.

Bottje, W. G., and P. C. Harrison. 1986. The effect of high ambient temperature on hypercapnia on postprandial intestinal hyperemia in domestic cockerels. Poultry Sci. 65:1606-1614.

Brake, J.T., and J.B. Carey. 1983. Induced molting of commercial layers. North Carolina Agricultural Extension Service Poultry Science and Technical Guide No. 10. North Carolina Agricultural Extension Service, Raleigh, NC.

Broom, D.M. (1986). Indicators of poor welfare. Br. Vet. J., 142:524-26.

Broom, D.M. and Johnson, K.G. (1993). Stress and Animal Welfare. Chapman and Hall, Animal Behaviour Series, Chapman and Hall, London, 211 pp.

Burton, R. R. and A.H. Smith, 1967. Effect of polycythemia and chronic hypoxia on heart mass in the chicken. J. Appl. Physiol. 22:782-785.

Carr, L. E., F. W. Wheaton, and L. W. Douglass. 1987. Empirical models to determine ammonia concentrations from broiler chicken litter. ASAE paper No. 87-4007. ASAE. St. Joseph, MI.

Castanon, F., R.W. Leeper, and C.M. Parsons. 1990. Evaluation of corn gluten feed in diets of laying hens. Poult. Sci. 69:90-97.

Charles, D.R., and C.G. Payne. 1966. The influence of graded levels of atmospheric ammonia on chickens. 1. Effects on respiration and on the performance of broilers and replacement growing stock. Br. Poult. Sci. 7:177-187.

Chiang, S. H. and W. M. Hsieh, 1995. Effect of direct-fed microbials on broiler growth and performance and litter ammonia level. Asian-Aust. J. An. Sci. 8:159-162.

Christmas, R.B., R.H. Harms, and O.M. Junqueira. 1985. Performance of Single Comb White Leghorn hens subjected to 4 or 10 day feed withdrawal force rest procedures. Poult. Sci. 64:2321-2324.

Craig, J.V., Craig J.A. and Vargas Vargas, J. (1986a). Cortecosteroids and other indicators of hens well-being in four laying-house environments. Poultry Sci. 65:856-63.

Craig, J.V., Vargas Vargas, J. and Milliken, G.A. (1986b). Fearful and associated responses of white leghorn hens: effects of cage environments and genetic stocks. Poultry Sci., 65:2199-2207.

Cueva, S., H. Sillau, A. Valenzuela, and H. Ploog. 1974. High altitude induced pulmonary hypertension and right heart failure in broiler chickens. Res. Vet. Sci. 16:370-374.

Cunningham, D. L, 1992. Beak trimming effects on performance, behavior, and welfare of chickens: A review. J. Appl. Poultry Res 1:129-134.

Cunningham, D. L., R. J. Buhr, and M. Mamputu, 1992. Beak trimming and sex effects on behavior and performance traits of large white turkeys. Poultry Sci. 71:1606-1614.

Darre, M. J. 1979. The influence of red light vs. white light rearing of broiler chicks on agonistic behavior, feed efficiency and oxygen consumption. Poultry Sci. 58:1048.

Darre, M. J. and A. H. Spanorf. 1985. Energy efficient cost effective lights for use with poultry. Poultry Sci.64 (Suppl 1):85

Dawkins, M. S. (1983a). Battery hens name their price: consumer demand theory and the measurement of ethological ?needs?. Anim. Behav., 31, 1195-1205.

Dawkins, M.S. (1983b). Cage size and flooring preferences in litter-reared and cage-reared hens. Br. Poult. Sci., 24:177-182.

Dawkins, M.S. and Hardie, S. (1989). Space needs for laying hens. Br. Poult. Sci., 30:413-416.

Davis, N.J., N. B. Prescott, C. J. Savory, C. and C. M. Wathes. 1999. Preferences of growing fowls for different light intensities in relation to age, strain and behavior. Animal Welfare 8(3):193-203.

Deaton, J.W., F.N. Reece, and B.D. Lott. 1984. Effect of atmospheric ammonia on pullets at point of lay. Poult. Sci. 63:384-385.

Denbow, D. M., A. T. Leighton, Jr., and R. M. Hulet, 1984. Behaviour and growth parameters of large white turkeys as affected by floor space and beak trimming. 1. Males. Poultry Sci. 63:31-37.

Donoghue, D. J., B. F. Krueger, B. M. Hargis, A. M. Miller, and M. E. El Halawani. 1989. Thermal stress reduces serum luteinizing hormone and bioassayable hypothalamic content of luteinizing hormone releasing hormone in the hen. Biol Reprod. 41:419-424.

Doyen, J. and Zayan, R. (1984). Measures of space in pairs of hens in battery cages. Behav. Proc., 9:157-160.

Duncan I. J. H. and Fraser, D. (1997). Understanding animal welfare. In: Animal Welfare. Ed. M. Appleby and B. Hughes. CAB International, London, UK. pp 19-31.

Duncan I. J. H. and J. C. Petherick 1991. The implications of cognitive processes for animal welfare. J. Anim. Sci., 69, 5071-5022.

Duncan, I.J.H., and D.G.M. Wood-gush. 1971. Frustration and aggression in the domestic fowl. Anim. Behav. 19:500-504.

Eddahibi, S., S. Adnot, C. Carville, Y. Bloquit, and B. Raffestin. 1992. L-Arginine restores endothelium-dependent relaxation in pulmonary circulation of chronically hypoxic rats. Am. J. Physiol. 263 (Lung Cell. Mol. Physiol. 7):L194-L200.

Estévez, I. (2002). Dealing with animal welfare issues: proactive strategies and voluntary regulations. Proceedings of the 49th Maryland Nutrition Conference, March 27-28, 2002, Timonium, MD. Edited by the Department of Animal and Avian Sciences, University of Maryland, College Park, MD. pp: 3-19.

Estevez, I., Newberry, R. and Arias de Reyna, L. (1997). Broiler chickens, A tolerant social system? Etología, 5:19-29.

Fedde, M. R. and R.F. Wideman, 1996. Blood viscosity in broilers: Influence on pulmonary hypertension syndrome. Poultry Sci. 75:1261-1267.

Forman, M. F., M. M. Beck, and S. E. Scheideler. 1996. Estrogen implants in heat-stressed hens: Effects on gut transport of calcium. Poultry Sci. 75:(Suppl)52.

Freed, M and I Estevez, 2002. Effects of stocking density on the behavior of domestic fowl; physical and social components. Poultry Sci. 80(supple):99

Gaskins, H. R., C. T. Collier, and D. B. Anderson, 2002. Antibiotics as growth promotants: Mode of action. Animal Biotechnology 13(1):29-42.

Gentle, M. J., 1986. Beak trimming in poultry. Worlds Poultry Sci. J. 42:268-275.

Gentle, M. J., and J. Breward, 1986. The bill tip organ of the chicken. J. Anatomy 145:79-85.

Gentle, M. J., B. O. Hughes, and R. C. Hubrecht, 1982. The effect of beak trimming on food intake, feeding behavior and body weight in adult hens. Appl. Animal Ethology 8:147-159.

Gentle, M. J., D. Waddington, L. N. Hunter, and R.B. Johnes, 1990. Behavioural evidence for persistent pain following partial beak amputation in chickens. Appl. Animal Behaviour Science. 27:149-157.

Gentle, M.J., B. H. Thorp, and B. O. Hughes, 1995. Anatomical consequences of partial beak amputation (beak trimming) in turkeys. Research in Vet. Sci. 58:158-162.

Grandin, T. 1996. Animal behavior, handling and facilities design: vocalizations correlate with stress in cattle and pigs. Report to USDA from Colorado State University.

Gross, W.B. and Siegel, H.S. (1983). Evaluation of the heterophil/lynphocyte ratio as a measure of stress in chickens. Avian Dis., 27:972-979.

Gunnarsson, S., Keeling L.J. and Svedberg, J. (1999). Effect of rearing factors on the prevalence of floor eggs, cloacal cannibalism and feather pecking in commercial flocks of loose housed laying hens. Br. Poult. Sci., 40:12-18.

Gunnarsson, S., Mathews, L.R., Foster, T.M. and Keeling, L.J. (2000). The demand for straw and feathers as litter substrates by laying hens. Appl. Anim. Behav. Sci., 65:321-330.

Hamrita, T.K., S.K. Hamrita, G. Van Wicklen, and M. Czarick. 1997. Use of Biotelemetry in Measurement of Animal Responses to Environmental Stressors. ASAE Paper number 97 008, St. Joseph, MI.

Harrison, P.C., and K.W. Koelkebeck. 2001. Influence of concentration of a topically applied manure inhibitor solution Al+Clear® on mass ammonia generation rate. Northeast Regional Project NE-127, Biophysical Models for Poultry Production Systems.

Harrison, P.C., and K.W. Koelkebeck. 2002. Influence of application frequency of a topically applied manure ammonia inhibitor solution (Al+Clear®) on mass ammonia generation rate. Northeast Regional Project NE-127, Biophysical Models for Poultry Production Systems.

Hecker, M., W.C. Sessa, H.J. Harris, E.E. Anggard, and J.R. Vane. 1990. The metabolism of L-arginine and its significance for the biosynthesis of endothelium-derived relaxing factor: Cultured endothelial cells recycle L-citrulline to L-arginine. Proc. Natl. Acad. Sci. USA. 87:8612-8616.

Heckert, R. A., Estévez, I., Russek-Cohen, E. & Pettit-Riley, R. (2002). Effects of density, heat stress and perch availability on the immune status of broilers. Poultry Science, 81:451-457.

Hess, P. Clozel, M. Clozel, J. 1996. Telemetry Monitoring of Pulmonary Arterial Pressure in Freely Moving Rats. Journal of Applied Physiology 81(2) 1027 1032.

Huff, W.E., G.W. Malone, and G.W. Chaloupka. 1984. Effect of litter treatment on broiler performance and certain litter quality parameters. Poult. Sci. 63:2167-2171.

Hughes, B.O. (1977). Selection of group size by individual laying hens, Br. Poult. Sci., 18:9-18.

Hughes, B. O., and M. J. Gentle, 1995. Beak trimming of poultry: its implications for welfare. Worlds Poultry Sci. J. 51:51-61.

Hynes, R.O. 1992. Integrins: versality, modulation, and signaling in cell adhesion. Cell. 69:11-25.

Imaizumi, T., Y. Hirooka, H. Masaki, S. Harada, M. Momohara, T. Tagawa, and A. Takeshita. 1992. Effects of L-arginine of forearm vessels and responses to acetylcholine. Hypertension 20:511-517.

Ingram, D.R and F. B. Mather, 1988. White leghorn production parameters as affected by body weight loss and length of rest period during a force molt. Nutr Rep Int. 37:901 908.

Jarvis, J. R., N. R. Taylor, N. B.. Prescott, I. Meeks, C. M. Wathes. 2002. Measuring and modeling the photopic flicker sensitivity of the chicken (Gallus gallus domesticus). Vision Research 42:99-106.

Joerger, R. D., 2003. Alternatives to antibiotics: Bacteriocins, antimicrobial peptides and bacteriophages. Poultry Sci. 82:640-647.

Johns, R.A., J.M. Linden, and M.J. Peach. 1989. Endothelium-dependent relaxation and cyclic GMP accumulation in rabbit pulmonary artery are selectively impaired by moderate hypoxia. Cir. Res. 65:1508-1515.

Jones, F. T., and S. C. Ricke, 2003. Observations of the history of the development of antimicrobials and their use in poultry feeds. Poultry Sci. 82:613-617.

Joseph, S. W., J. R. Hayes, L. L. English, L. E. Carr, and D. D. Wagner, 2001. Food Addit. Contam. 18(12):1118-1123.

Julian, R. J., 1989. Lung volume of meat-type chickens. Avian Dis. 33:174-176.

Julian, R.J. 1993. Ascites in poultry. Avian Pathol. 22:419-454.

Julian, R. J., J. Summers, and J. B. Wilson. 1986. Right ventricular failure and ascites in broiler chickens caused by phosphorus-deficient diets. Avian Dis. 30:453-459.

Keeling, L. J., Estévez, I., Newberry, R. C. & Correia, M. G. (2003). Production related traits of layers reared in different sized flocks: The concept of problematic ?intermediate? group sizes. Poultry Science, 82:1393-1396.

Keshavarz, K., and F.W. Quimby. 2002. An investigation of different molting techniques with an emphasis on animal welfare. J. Appl. Poult. Res. 11:54-67.

Kettlewell, P.J., M.A. Mitchell, and I.R. Meeks. 1997. An implantable radio telemetry system for remote monitoring of heart rate and deep body temperature in poultry. Computers and Electronics in Agric. 17: 161 175.

Kim, W.K., and P.H. Patterson. 2003. Effect of minerals on activity of microbial urease to reduce ammonia volatilization in poultry manure. Poult. Sci. 82:223-231.

Klein-Hessling, H., 2001. Poultry feeding programs without antibiotics. Proceedings 62nd Minnesota Nutrition Conference, University of Minnesota, pp. 215-230.

Koelkebeck, K.W., P.C. Harrison, and G.L. Riskowski. 2001. Effect of a feed additive or manure treatment application on the mass generation rate of ammonia produced from laying hen manure. Poultry Sci. 80(Suppl. 1):89.

Koelkebeck, K.W., C.M. Parsons, R.W. Leeper, S. Jin, and M.W. Douglas. 1999. Early postmolt performance of laying hens fed a low-protein corn molt diet supplemented with corn gluten meal, feather meal, methionine, and lysine. Poult. Sci. 78:1132-1137.

Koelkebeck, K.W., C.M. Parsons, M. Douglas, R.W. Leeper, S. Jin, X. Wang, Y. Zhang, and S. Fernandez. 2001b. Early postmolt performance of laying hens fed a low-protein corn molt diet supplemented with spent hen meal. Poult. Sci. 79:80:353-357.

Koelkebeck, K.W., C.M. Parsons, R.W. Leeper, and J. Moshtaghian. 1991. Effect of protein and methionine levels in molt diets on postmolt performance of laying hens. Poult. Sci. 70:2063-2073.

Koelkebeck, K.W., C.M. Parsons, R.W. Leeper, and J. Moshtaghian. 1992. Effect of duration of fasting on postmolt laying hen performance. Poult. Sci. 71:434-439.

Koelkebeck, K.W., C.M. Parsons, R.W. Leeper, and X. Wang. 1993a. Effect of supplementation of a low-protein corn molt diet with amino acids on early postmolt laying hen performance. Poult. Sci. 72:1528-1536.

Koelkebeck, K.W., C.M. Parsons, and R.W. Leeper. 1993b. Effect of early feed withdrawal on subsequent laying hen performance. Poult. Sci. 72:2229-2235.

Kostal, L., and Savory, C.J. (1994). Influence of pharmacological manipulation of dopamine and opioid receptor subtypes on stereotyped behavior of restricted-fed fowls. Pharmacol. Biochem. Behav., 48:241-252.

Lagadic, H. and Faure, J.M. (1987). Preferences of domestic hens for cage size and floor types as measured by operant conditioning. Appl. Anim. Behav. Sci., 19:147-155.

Leeson S. and Summers, J.D. 1985. Response of growing Leghorn pullets to long or increasing photoperiods. Poultry Sci. 64:1617-1622.

Lewis, P.D. and T. R. Morris. 1998. A comparison of the effects of age at photostimulation on sexual maturity and egg production in domestic fowl, turkeys, partridges and quail. Worlds Poultry Science 54:119-128.

Lewis, P.D. and T. R. Morris. 1999. Light intensity and performance of domestic pullets. World Poultry Science 55:241-25.

Lewis, P.D. and T. R. Morris. 2000 Poultry and coloured light. World Poultry Science 56:189-208.

Lewis, P.D., G. C. Perry, C. M Sherwin and C. Moinard. 2000. Effect of ultraviolet radiation on the performance of intact male turkeys. Poultry Sci. 79:850-855.

Liu, S., D.E. Crawley, P.J. Barnes, and T.W. Evans. 1991. Endothelium-derived relaxing factor inhibits hypoxic pulmonary vasoconstriction in rats. Am. Rev. Respir. Dis. 143:32-37.

Luscher, T.F., and P.M. Vanhoutte. 1986. Endothelium-dependent contractions to acetylcholine in the aorta of the spontaneously hypertensive rat. Hypertension 8:344-348.

Mahmoud, K., M. M. Beck, S. E. Scheideler, M. F. Forman, K. P. Anderson, and S. D. Kachman. 1996. Acute high environmental temperature and calcium-estrogen relationships in the hen. Poultry Sci. 75:1555-1562.

Marder, J., and Z. Arad. 1989. Panting and acid-base regulation in heat stressed birds. Comp. Biochem. Physiol. 94A:395-400.

Mather, F. B., G. A. Barnas, and R. E. Burger. 1980. The influence of alkalosis on panting. Comp. Biochem. Physiol. 67A:265-268.

Malone, G.W. 1987. Chemical litter treatments to control ammonia. Proc. of the 22nd meeting on Poultry Health and Condemnations, Ocean City, MD.

Marler, P, Dufty, A. and Pickert, R. 1986. Vocal communication in the domestic chicken: II. Is a sender sensitive to the presence and nature of a receiver? Animal Behavior 34:194-198.

Martinez, L.A., J. S. Jeffrey, and T.W. Odom. 1997. Electrocardiographic diagnosis of cardiomyopathies in Aves. Poult. Avian Biol. Rev. 8: 9-20.

Martinez-Lemus, L.A., M.W. Miller, J.S. Jeffrey, and T.W. Odom. 1998. Echocardiographic evaluation of cardiac structure and function in broiler and leghorn chickens. Poultry Sci. 77:1045-1050.

Martinez-Lemus, L.A., R.K. Hester, E.J. Becker, J.S. Jeffrey, and T.W. Odom. 1999. Pulmonary artery endothelium-dependent vasodilation is impaired in a chicken model of pulmonary hypertension. Am. J. Physiol. 277:R190-7.

Martinez-Lemus, L.A., M.W. Miller, J.S. Jeffrey, and T.W. Odom. 2000. Echocardiographic study of pulmonary hypertension syndrome in broiler chickens. Avian Dis. 44:74-84.

Maxwell, M.H., G.W. Robertson, and S. Spence. 1986. Studies on an ascitic syndrome in young broilers. 1. Haemotology and pathology. Avian Pathol. 15:511-524.

Maxwell, M. H., S. G. Tullett, and F.G. Burton, 1987. Haematology and morphological changes in young broiler chickens with experimentally induced hypoxia. Res. Vet. Sci. 43:331-338.

McCormick, C.C., and D.L. Cunningham. 1984. High dietary zinc and fasting methods of forced resting: a performance comparison. Poult. Sci. 63:1201-1206.

McCormick, C.C., and D.L. Cunningham. 1987. Performance and physiological profiles of high dietary zinc and fasting as methods of inducing forced rest: A direct comparison. Poult. Sci. 66:1007-1013.

Mirsalimi, S. M., P. J. O'Brien, and R. J. Julian, 1992. Changes in erythrocyte deformability in NaCl-induced right-sided cardiac failure in broiler chickens. Am. J. Vet. Res. 53:2359-2363.

Mogford, J.E., S.H Platts, G.E. Davis, and G.A. Meininger. 1996. Vascular smooth muscle integrin mediates arteriolar vasodilatation in response to RGD peptides. Circ. Res. 79:821-826.

Mogford, J.E., G.E. Davis, and G.A. Meininger. 1997. RGDN peptide interaction with endothelial alpha 5 beta 1 integrin causes sustained endothelin-dependent vasoconstriction of the rat skeletal muscle arterioles. J. Clin. Invest. 100:1647-1653.

Moore, P.A., Jr., T.C. Daniel, D.R. Edwards, and D.M. Miller. 1995. Effect of chemical amendments on ammonia volatilization from poultry litter. J. Environ. Qual. 24:293-300.

Mulligan, B.E., Baker, S.C. and Murphy, M.R. 2003. Vocalizations as indicators of emotional stress and psychological well-being in animals. USDA AWIC newsletter 5 (3): 1-3.

Naber, E.C., J.D. Latshaw, and G.A. Marsh. 1984. Effectiveness of low sodium diets for recycling of egg production type hens. Poult. Sci. 63:2419-2429.

National Research Council. 1994. Nutrient Requirements of Poultry. Washington, DC: National Academy Press.

Nesbeth, W.G., C.R. Douglas, and R.H. Harms. 1976. Response of laying hens to a low salt diet. Poult. Sci. 55:2128-2133.

Newberry, R.C., and J.W. Hall. (1990). Use of pen space by broiler chickens, effects of age and pen size. Applied Animal Behaviour Science, 25: 125-136.

Noble, D. O., and K. E. Nestor, 1997. Beak trimming of turkeys. 2. Effects of arc beak trimming on weight gain, feed intake, feed wastage, and feed conversion. Poultry Sci. 76:668-670.

Noble, D. O., F. V. Muir, K. K. Krueger, and K. E. Nestor, 1994. The effect of beak trimming two strains of commercial tom turkeys. 1. Performance traits. Poultry Sci. 73:1850-1857.

Novero, R. P., M. M. Beck, E. W. Gleaves, A. L. Johnson, J. A. Deshazer. 1991. Plasma progesterone, luteinizing hormone concentrations, and granulosa cell responsiveness in heat-stressed hens. Poultry Sci. 70:2335-2339.

Odom, T. W., P. C. Harrison, and W. G. Bottje. 1986. Effects of thermal induced respiratory alkalosis on blood ionized calcium levels in the domestic hen. Poultry Sci. 65:570-573.

Odom, T. W. 1993. Ascites syndrome: Overview and update. Poult. Dig. 52:14-22.

Odom, T., B. Hargis, C. Lopez, M. Arce, Y. Ono, and G. Avila. 1991. Use of electrocardiographic analysis for investigation of ascites syndrome in broiler chickens. Avian Dis. 35:738-744.

Odom, T.W., L.M. Rosenbaum, and B.M. Hargis. 1992. Evaluation of vectorelectrocardiographic analysis of young broiler chickens as a predictive index for susceptibility to ascites syndrome. Avian Dis. 36:78-83.

Odom, T.W., L.M. Rosenbaum, and J.S. Jeffrey. 1995. Experimental Reduction of Eggshell Conductance During Incubation. I. Effect on the Susceptibility to Ascites Syndrome. Avian Dis. 39:821-829.

Odom, T.W., R.K. Hester, E.J. Becker, L.A. Martinez, G.A. Ramirez, and J.S. Jeffrey. 1996. Effect of in vitro hypoxic and normoxic conditions in fast- and slow-growing chicken pulmonary arteries. Poultry Sci. 75(Suppl. 1):76.

Odom, T., B. Hargis, C. Lopez, M. Arce, Y. Ono, and G. Avila. 1991. Use of electrocardiographic analysis for investigation of ascites syndrome in broiler chickens. Avian Dis. 35:738-744.

Palmer, R.M. J., D.S. Aston, and S. Moncada. 1988. Vascular endothelial cell synthesize nitric oxide from L-arginine. Nature 333:664-666.

Palmer, R. M.J., A.G. Ferrige, and S. Moncada. 1987. Nitric oxide accounts for the biological activity of endothelium-derived relaxing factor. Nature (Lond.) 288:373-376.

Panza, J.A., P.R. Casino, D.M. Badar, and A. A. Quyyumi. 1993. Effect of increased availability of endothelium-derived nitric oxide precursor on endothelium-dependent vascular relaxation in normal subjects and in patients with essential hypertension. Circulation 87:1475-1481.

Parkhurst, C.R., P.B. Hamilton, and G.R. Baughman. 1974. The use of fatty acids for the control of microorganisms in pine saw dust litter. Poult. Sci. 53:801-806.

Patterson, P.H., J.P. Blake, and K.D. Roberson. 2002. Proceedings 2002 National Poultry Waste Management Symposium. October28-30, Birmingham, AL.

Patterson, P. H. and M. J. Darre. 2002. Light parameters and hen performance of
commercial Leghorns illuminated with red and white fluorescent lamps. Poultry Sci.80(supplement 1) 139.

Patterson, P.H. and Siegel, H.S. (1998). Impact of cage density on pullet performance and blood parameters of stress. Poultry Sci., 77:32-40.

Peacock, A.J., C. Pickett, K. Morris, and J.T. Reeves. 1989. The relationship between rapid growth and pulmonary hemodynamics in the fast-growing broiler chicken. Am. Rev. Respir. Dis. 139:1524-1530.

Persyn, K. E., H. Xin, A. Ikeguchi, and R. S. Gates, 2004. Feeding behaviors of laying hens with or without beak trimming. Tras. ASAE 47(2):591-596.

Prayitno, D. S. and C.J.C. Phillips. 1997. Equating the perceived intensity of coloured lights to hens. British Poultry Science 38:136-141.

Prayitno, D. S., C. J. C. Phillips and H. Omed. 1997a The effects of color of lighting on the behavior and production of meat chickens. Poultry Sci 76:452-457.

Prayitno, D. S., C. J. C. Phillips, D. K. Stokes. 1997b. The effects of color and intensity of lighting on behavior and leg disorders in broiler chickens Poultry Sci. 76:1674-1681.

Prescott, N. B. and C. M. Wathes. 1999. Spectral Sensitivity of the domestic fowl (Gallus gallus domesticus). British Poultry Science 40:332-339.

Prescott, N.B and C.M. Waithes. 2002. Preference and motivation of laying hens to eat under different illuminances and the effect of illuminance on eating behavior. British Poultry Science 43:190-195.

Price, S. and Sibly, R. (1993). Heart-rate of red deer during routine handling procedures taking account of motor activity and basal metabolic rate. Appl. Anim. Beh. Sci., 35:297-298.

Pyrzak, R., N. Snapir, G. Goodman, E. Arnon and M. Perek. 1986. The influence of light quality on initiation of egg laying by hens. Poultry Sci. 64:1617-1622.

Randall, M.D., and T.M. Griffith. 1991. Differential effects of L-arginine on the inhibition NG nitro-L-arginine methyl ester of basal and agonist-stimulated EDRF activity. Br. J. Pharmacol. 104: 743-749.

Reece, F.N., B.D. Lott, and J.W. Deaton. 1980. Ammonia in the atmosphere during brooding affects performance of broiler chickens. Poult. Sci. 59:486-488.

Rees, D.D, R.M.J. Palmer, A., and S. Moncada. 1989. Role of endothelium-derived nitric oxide in the regulation of blood pressure. Proc. Natl. Acad. Sci. USA. 86:3375-3378.

Renner, P. A., K. E. Nestor, and G. B. Havenstein, 1989. Effects on turkey mortality and body weight of type of beak trimming, age at trimming, and injection of poults with vitamin and electrolytes solution at hatching.
Poultry Sci. 68:369-373.

Ricke, S. C., 2003. Perspectives on the use of organic acids and short chain fatty acids as antimicrobials. Poultry Sci. 82:632-639.

Ross, E., and R.B. Herrick. 1981. Forced rest induced by molt or low-salt diet and subsequent hen performance. Poult. Sci. 60:63-67.

Roush, W. B. 1986. A decision analysis approach to the determination of population density in laying cages. World's Poultry Sci J. 42:26-31.

Roush, W.B., Bock, R.G. and Marszalek, M.A. (1989). Evaluation of crowding of caged laying hens (Gallus gallus) using fuzzy set decision analysis. Appl. Anim. Behav. Sci., 23:155-163.

Roush, W.B. and T.L. Cravener. 1992. Choosing a commercial laying hen strain based on multicriteria decision analysis. J. Appl. Poultry Res. 1:403-409.

Roush, W.B., M. M. Mashaly, and H.B. Graves. 1984. Effect of increased bird population in a fixed cage area on production and economic responses of Single Comb White Leghorn laying hens. Poultry Sci. 63:45-48.

Roush, W.B., R.G. Bock, and M. A. Marszalek. 1989. Evaluation of crowding of caged laying hens (Gallus domesticus) using fuzzy set decision analysis. Applied Animal Behaviour Science 23:155-163.

Roybal, J. (Ed.) 2003. Welfare audits will come. Beef Magazine February, Primedia Business magazines and media PP. 1-3.

Ruszler, P.L. 1996. The keys to successful force molting. Virginia Cooperative Extension Service, Publication 408-026 (revised), Blacksburg, VA.

Scheideler, S. E. 1990. Research Note: Effect of various light sources on broiler performance and efficiency of production under commercial conditions. Poultry Sci. 69:1030-1033.

Scheideler, S.E., M.M. Beck, and Leanne LaBrash. 2003. Non-feed withdrawal programs for laying hen molt. Poult. Dig. Vol. 3, No. 7, 3 pages.

SAS Institute. SAS User's Guide Statistics. Cary, NC: SAS Institute, 1988.
Staten, F. E., and P. C. Harrison. 1987. Respiratory alkalosis and calcium excretion in heat stressed domestic hens. Fed. Proc. 46:1441.

Struwe, F.J., 1990. Management induced stress and its measurement in poultry. PhD Dissertation, University of Nebraska-Lincoln, Lincoln, NE 68583.

Tamir, H., and S. Ratner. 1963. Enzymes of arginine metabolism in chicks. Arch. Biochem. Biophys. 102:249-258.

Tamir, H., and S. Ratner. 1963. A study of ornithine, citrulline and arginine synthesis in growing chicks. Arch. Biochem. Biophys. 102:259-269.

Van Den Buuse, M. 1994. Circadian Rhythms of Blood Pressure, Heart Rate, and Locomotor Activity in Spontaneously Hypertensive Rats as Measured With Radio telemetry. Toxicology 55:4 783 787.

Vandegrift, K.J., T.L. Cravener, R.M. Hulet and W. B. Roush. 2003. Analysis of the nonlinear dynamics of daily broiler growth and feed intake. Poultry Sci. 28:1091-1099.

Verstegen, M. W. A., and B. A. Williams, 2002. Alternatives to the use of antibiotics as growth promoters for monogastric animals. An. Biotechnology 13(1): 113-127.

Wideman, R.F. 2000. Cardio-pulmonary hemodynamics and ascites in broiler chickens. Poult. Avian Biol. Rev. 11:21-43.

Wideman, R.F., Y.K. Kirby, M. Ismai, W.G. Bottje, R.W. Moore, and R.C. Vardeman. 1995. Supplemental L-arginine attenuates pulmonary hypertension syndrome (ascites) in broilers. Poult. Sci. 74:323-330.

Wideman, R.F., Y.K. Kirby, C.D. Tackett, N.E. Marson, and R.W. McNew. 1996. Cardio-pulmonary function during acute unilateral occlusion of the pulmonary artery in broilers fed diets containing normal or high level of arginine-HCl. Poult. Sci. 75:1587-1602.

Webster, A.B. 2000. Behavior of White Leghorn laying hens after feed withdrawal. Poult. Sci. 79:192-200.

Welton, L. A., L. A. Thal, M. B. Perri, S. Donabedian, J. McMahon, J. W. Chow, and J. M. Zervos, 1998. Antimicrobial resistance in enterococci isolated from turkey flocks fed virginiamycin. Antimicrobial Agents and Chemotherapy 42(3):705-708.

Whitehead, C.C., and D.W.F. Shannon. 1974. The control of egg production using a low-sodium diet. Br. Poult. Sci. 15:429-434.

Widowski, Tina M., Keeling, Linda J., and Duncan, Ian J. H. 1992. The preferences of hens for compact fluorescent over incandescent lighting. Can. J. Anim. Sci. 72:203-211.

Xin, H., A. Tanaka, T. Wang, R. S. Gates, E. F. Wheeler, K. D. Casey, A. J. Heber, J. Ni and T, Lin. 2002. A portable system for continuous ammonia measurement in the field. Paper No. 024168. American Society of Agriculture Engineers, St Joseph, MI: ASAE.

Yanagisawa, M., H. Kurihara, S. Kimura, Y. Tomobe, M. Kobayashi, Y. Mitsui, Y. Yazaki, K. Goto, and T. Masaki. 1988. A novel potent vasoconstrictor peptide produced by vascular endothelial cells. Nature 332:411-415.

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