Brief Summary of Minutes of Annual Meeting

Multi-State Project W2010  

Molecular Mechanisms that Regulate Efficiency of Feed Utilization in Beef Cattle.

Annual Meeting 2014 – Minutes.

The W2010 Annual Meeting was held in Association with the Joint Animal Science Societies meeting in Kansas City, July 22 and July 23, 2014.

Tuesday, July 22.

The meeting was opened by the Chair, Dr Mike Davis at 7:00 p.m.

Members Present:  Mike Davis (Ohio State U), Roberto Sainz and James Oltjen (UC Davis), Stephanie Hansen (Iowa State U), Gordon Carstens (Texas A&M U), Rod Hill (U Idaho), Dan Shike (U Illinois), Jamie Matthews (U Kentucky), Bob Wettermann and Brit Boelmer (Oklahoma State U), Jennifer Thompson (Montana State U), Scott Lake (U Wyoming).

Guests Present: Allison Sunstrum, Camiel Huisma, Eliel Gonzalez.

Agenda: Presentation of Station Reports.

Adjournment: 10:00 p.m.

Wednesday, July 23.

The meeting was opened by Chair, Dr Mike Davis at 7:00 p.m.

Members Present:  Mike Davis (Ohio State U), Roberto Sainz and James Oltjen (UC Davis), Gordon Carstens (Texas A&M U), Rod Hill (U Idaho), Jamie Matthews (U Kentucky), Bob Wettermann and Brit Boelmer (Oklahoma State U), Jennifer Thompson (Montana State U), Samoda Fernando (U Nebraska Lincoln), Philip Lancaster (U Florida), Allison Meyer (U Missouri).

Agenda:

Business Meeting:  Rod Hill (U Idaho) was to move from Secretary to Chair for 2014-15, but announced that he was relocating to a position in Australia and could not continue.  Nominations for both Chair and Secretary for 2014-15 were called.  Allison Meyer (U Missouri), Chair and Samoda Fernando (U Nebraska Lincoln), Secretary were both unanimously elected.

The Business meeting was followed by presentation of the remaining station reports.

Adjournment: 10:00 p.m.

W2010 Annual Report 2015

Accomplishments

Short-term Outcomes: The main short-term outcome of the W2010 project is increased scientific knowledge of beef cattle feed efficiency in the scientific and industry communities. To this end, members of W2010 present their research findings at scientific meetings, train graduate students, work with bull test stations to determine RFI, work with feed companies to design diets that enhance efficiency of cattle fed forage and grain-based diets, work with breed associations to create efficiency-related EPDs, organize and present at producer-targeted extension meetings, and create producer-targeted publications to increase knowledge regarding feed efficiency.

Outputs: Data outputs from experiments conducted by members of W2010 are described below. Collaborative grant proposals have been submitted by committee members, including some large AFRI Integrated proposals. Other outputs of the W2010 group include a recently published book entitled “Feed Efficiency in the Beef Industry”, the writing and publication of which was led by Rod Hill. All of the chapters except one were authored or co-authored by members of W2010. Additionally, 20 peer-reviewed journal articles, 2 conference proceedings papers, 3 scientific abstracts, and 7 experiment station/extension reports have been published by this group on related topics in the past year (listed in Publications).

Activities

Iowa State University:

Objective 1:    To understand biological sources of variation in efficiency of feed utilization as quantified by traits such as RFI.

This work was conducted in collaboration between committee members from the University of Missouri and Iowa State University. Work in this year continued to focus on the contribution of diet digestibility to feed efficiency ranking of feedlot steers. Over 2 yr, 373 steers (in two groups) were fed for 70 d at the University of Missouri for a growing phase and then shipped to Iowa State University for the finishing phase. Steers were fed in GrowSafe bunks during both phases. At Missouri, steers were fed whole shell corn (G-Corn) or roughage-based (G-Rough) diets. Within each group, the 12 greatest and 12 least feed efficient steers from each growing diet (n = 96 total; 48 steers/group; 488 ± 5 kg) were selected for further evaluation. At Iowa State, steers were fed an average of 10 g titanium dioxide·steer^-1·d^-1 (TiO₂) in receiving phase diets nutritionally similar to growing phase diets for 14 d, followed by a 2 d fecal collection to determine diet DM digestibility. For finishing, steers were transitioned to byproduct (F-Byp) or corn-based diets (F-Corn). Optaflexx (200 mg/d) was fed for 28 d prior to harvest and the TiO₂ protocol was repeated immediately before introducing Optaflexx to determine diet DM digestibility during finishing. Data for the 96 steers were pooled, steers were ranked by growing phase G:F, and then classified as the 24 greatest (HFE) or 24 least (LFE) feed efficient steers from each GP diet. Data were analyzed using PROC MIXED of SAS with group applied as a fixed effect. There was a positive correlation for DM digestibility between growing and finishing phases for steers fed nutritionally similar diets during both feeding phases but a negative correlation for G:F between phases in steers that were grown on roughage and finished on corn. Growing period fiber digestion was markedly improved in steers ranked as highly feed efficient during the growing period, suggesting that improved ability to utilize the diet may contribute to better feed efficiency. Finishing G:F was greater in steers ranked as highly efficient during the growing period vs. those ranked as lowly efficient during the growing period, but there was no difference in growing or finishing DM digestion due to feed efficiency classification. There was a positive correlation for DM digestibility between feeding phases when steers were grown and finished on similar diets. Overall, FE was repeatable but was negatively correlated between phases when steers were roughage grown and corn finished, reinforcing the idea that cattle should be feed efficiency tested using diet types similar to the production environment of interest.

Montana State University:

Objectives and Relevant Research under each:

1. To understand biological sources of variation in efficiency of feed utilization.

The current study is evaluating individual animal variation in extreme high and extreme low RFI growing lambs. High and low RFI animals are identified after 42-d feeding trial. Use of a human triaxial pedometer for measuring activity level in sheep was evaluated (manuscript submitted). Differences in body composition for lambs divergent for RFI were found. More efficient lambs had heavier rumen and lung weights than inefficient lambs.

A second study was conducted to evaluate the anabolic activity of progesterone in increasing feed utilization efficiency in mature ewes. Analysis of the resulting data is underway.

1. To discover physiological biomarkers and genetic markers for feed efficiency.

A recent paper was published in which we evaluated the predictive power of blood metabolites measured by NMR on prediction of phenotypic variation in RFI in feedlot cattle.

Collaborations with Texas A&M University are being carried out to confirm previous results with additional resolution.

Ongoing Research:

1. Hatch Projects – Investigating the underlying physiology of economically important traits in livestock genetic improvement
2. Wildlife Genomics – Bighorn sheep population study, Argali sheep in Kyrgyzstan
3. Feed Efficiency – Sheep RFI testing and physiological measurements in Fall 2014
4. Relationship between progesterone concentration and feed efficiency in Fall and Winter 2014
5. Funding for NSF, Wild Sheep Foundation, National Geographic for genotyping of Rocky Mountain Bighorn Sheep
6. Bair Ranch Foundation Funding for Candidate marker and gene identification in American Simmental Association Carcass Merit Project
7. Bair Ranch Foundation Funding for Gene Expression Profiling in muscle of beef carcasses differing in quality grade.

Recent Outputs:

1. Proceedings papers and presentations at WSASAS meeting, ASAS JAM, SSASAS, Stress Physiology Symposium, Montana State University College of Agriculture Research Report
2. Approximately 1,800 DNA samples archived on Bighorn Sheep, Mountain Goat, Cattle, and Sheep

The Ohio State University:

Objective 1:    To understand biological sources of variation in efficiency of feed utilization as quantified by traits such as RFI.

A divergent selection experiment was initiated in 1989 to investigate the influence of changes in serum IGF-I concentration on economically important traits in Angus cattle. The selection experiment included 100 spring-calving (50 high line and 50 low line) cows located at the Eastern Agricultural Research Station, Belle Valley, OH.

Beginning with the 2009 breeding season, the selection criterion in the IGF-I selection lines was changed from serum IGF-I concentration to ME EPD as provided by the Red Angus Association.  Females in the high line are mated to one of three high (undesirable) ME EPD bulls and cows and heifers in the low line are mated to one of three low (desirable) ME EPD bulls.  The first calves produced in this project at the Ohio station were born in the spring 2010 calving season.

Numbers of high and low line calves born in the spring 2010 through 2015 calving seasons were 26 and 19, 25 and 21, 9 and 10, 19 and 14, 26 and 13, and 25 and 13, respectively.  Number of calves born in 2012 was low due to a delayed shipment of semen.  Birth weight, weaning weight, preweaning relative growth rate, docility score at weaning, and serum IGF-I concentration at weaning were analyzed using PROC GLM in SAS.  The statistical model included the fixed effects of year-selection line, sex of calf, and age of dam, as well as the random effect of sire nested within year-line, and a covariate for age of calf at weaning for all dependent variables other than birth weight.  Sire nested within line was used as the error term in analysis of variance F tests for selection line.

The same Red Angus bulls were used to produce the 2010, 2011, and 2012 calf crops.  Average ME EPDs of the 3 high line and 3 low line sires were 12.7 and -8.0, respectively.  Average ME EPDs of the 3 sires of the high line calves and 3 sires of the low line calves born in 2013 and 2014 were 2.7 vs. 1.0 and -1.0 vs 1.0, respectively.  Average ME EPDs of the 2 high line sires of the calves born in 2015 was 8.0, whereas the average ME EPDs of the 2 sires of the low line calves born in the same year was 3.0.  In general, low accuracy sires were used to produce the 2013, 2014, and 2015 calf crops.  In several instances the ME EPDs of these bulls changed between when they were selected for breeding and the fall 2015 National Cattle Evaluation.

High line calves tended to have heavier birth weights than low line calves within each year (P = 0.08 for the effect of year-line).  Weaning weights were 6, 15, 5, 3, and 3 kg heavier for high line than for low line calves in 2010, 2011, 2012, 2013, and 2014, respectively (P = 0.50 for the effect of year-line).  Low line calves weighed 5 kg more than high line calves at weaning in 2015.  The effect of year-line on relative growth rate from birth to weaning was not significant (P = 0.31).  Low line calves (i.e., those sired by low or desirable ME EPD Red Angus bulls) born in 2010 averaged 344 + 13 ng/mL of serum IGF-I at weaning, whereas high line calves (i.e., those sired by high or undesirable ME EPD Red Angus bulls) born in the same year averaged 271 + 12 ng/mL.   This result was somewhat unexpected as most (but not all) previous studies have shown lower serum IGF-I concentration to be associated with more desirable feed efficiency.  Serum IGF-I concentrations for calves born in 2011 and 2013 were 24 and 15 ng/mL, respectively, greater in the high line calves than in the low line calves, results that were more in line with expectations, whereas IGF-I concentrations of calves born in 2012 were 11 ng/mL greater for low line than for high line calves.  Serum IGF-I concentrations of high and low line calves born in 2014 and 2015 were very similar.  Therefore, a consistent relationship between IGF-I concentration of progeny at weaning and ME EPD of their sires has not been observed thus far in this study.

Sex of calf was significant only for birth weight and weaning weight with bull calves on average weighing 1.9 and 13 kg more than heifer calves at birth and weaning, respectively.  As expected, means for age of dam differed significantly for birth weight and weaning weight.

Recording of BIF docility scores of calves at weaning was initiated in 2014.  Least squares means for docility scores of high vs. low line calves in 2014 and 2015 were 1.51 vs. 1.95 and 1.28 vs. 1.94, respectively, indicating that low line calves were slightly more restless in the squeeze chute (P = 0.16 for the effect of year-season).  Bull calves also tended to be more restless than heifer calves (P = 0.11).  Only small age of dam effects on temperament of calves were observed (P = 0.14).

University of California-Davis:

Modeling analyses indicate that genetic progress in our beef cattle breeds during the past 30 yr has resulted in phenotypic predictions that fall short of actual performance. These real physiological changes can be accommodated by reparameterization of our models, so that they reflect the greater genetic potential of our modern cattle herd. Updated models are now available for use by nutritionists and other professionals to aid in management decision making.

In support of Objectives 3 and 4:

3. To develop EPDs, informed by molecular studies in building multi-trait selection indices and decision-support tools to facilitate selection for improved FE in beef cattle.

4. To develop producer educational programs to enhance technology adoption by the beef industry.

We have collected literature data for genetic and technological improvements in beef cattle production in order to develop improved models for high accuracy EPDs, for RFI, and other production traits. Models are being modified by identifying and quantifying parameters that reflect efficiency differences between animals, allowing estimation of system effects of selection or feeding animals of different efficiencies.

University of Illinois:

Two experiments were conducted to evaluate the relationship between measures of feed efficiency in growing and mature animals, as well as across diet types. In Exp. 1, postweaning DMI, ADG, and backfat were evaluated on Angus and SimAngus heifers (n=623) over a 6-yr period. Heifers received similar forage-based diets, and individual DMI were recorded using the GrowSafe system. Residual feed intake (RFI), residual BW gain (RG), and residual intake and BW gain (RIG) were calculated. Heifers were classified into high, medium, or low RFI, RG, RIG, and DMI groups. The objective of this experiment was to determine the relationship between postweaning feed efficiency and intake in heifers, and subsequent cow performance and reproduction as 2-yr-old cows. As heifer RFI improved, cow forage DMI was reduced (P < 0.01). The RFI classification did not affect (P ≥ 0.07) reproductive traits; calf birth or weaning BW; cow BW, milk production, backfat, or BCS. Heifer DMI was highly correlated (P < 0.05) with cow forage intake. Heifers classified as low DMI were least frequently (P < 0.01) kept as replacements and were youngest (P = 0.04) at first calving. Calves from cows, classified as high DMI heifers, had the greatest (P < 0.01) birth BW; yet, there were no differences (P=0.60) in weaning BW. Intake classification had no effect (P ≥ 0.07) on cow BCS, backfat, or milk production. Cows, classified as low DMI heifers, weighed the least (P = 0.02) and had reduced (P < 0.01) hip heights at 60- and 240-d postpartum. Cows, classified as low DMI heifers, had reduced (P ≤ 0.01) DMI compared to cows within the high heifer DMI group. These data indicate that females classified as more efficient have reduced cow DMI without compromising production traits.

In Exp. 2, Charolais crossbred heifers and steers (n=628) were fed for two 70-d periods and DMI, ADG, and 12^th rib fat thickness were recorded. Steers were fed grain-based diets during the growing and finishing periods to determine the effects of test period and timing on DMI and feed efficiency. Heifers were fed forage during the growing period and grain during the finishing period to test the effect of diet type on DMI and measures of feed efficiency. For each 70-d test period, individual DMI was recorded using the GrowSafe system. Residual feed intake was calculated for each test period. Total feeding period ADG (FP_ADG) was calculated for steers by regressing all weights taken from feedlot arrival to final BW, which was calculated by dividing HCW by a standard dressing percentage (63%). Dry matter intake and RFI were correlated (r=0.56; P<0.01, and 0.63; P<0.01, respectively) for the growing and finishing periods of grain-fed steers. Average daily gain was not repeatable (r=0.11; P=0.06) across both test periods for steers. However, growing and finishing ADG were correlated (r=0.58; P<0.01, and r=0.69; P<0.01, respectively) to FP_ADG. To assess the potential of shortening the intake test, DMI was analyzed in 7-d increments for grain-fed steers during the growing period. Regardless of test length, from 7 to 70 d, DMI was correlated (r≥0.87; P<0.01) with total DMI during the growing period. Heifer forage DMI was correlated (r=0.58; P<0.01) with grain DMI; and, heifer forage ADG was negatively correlated (r=-0.30; P<0.01) with grain ADG. Forage and grain RFI were moderately correlated (r=0.40; P<0.01) for heifers.

One outcome of this project was the training and professional development of a PhD student. The student not only had the experience of collecting and analyzing data but also had the opportunity to attend professional meetings and present the results to producers at field days.

We have collected feed intake and performance data on >600 replacement heifers and subsequently collected intake and performance data on ~400 of these females as 2-yr-old cows and ~150 as 5-yr-old cows. We have also collected feed intake on different diet types during the growing and finishing period of over 600 feedlot cattle.

We have conducted experiments to achieve better understanding of relationships of feed intake and efficiency across different diet types and different biological time points. We have presented the data at field days and conferences:

“Measuring & Improving Beef Cow Maternal Efficiency & Profitability” presented at the Cornbelt Cow-Calf Conference, January 31, 2015 in Ottumwa, IA

University of Kentucky:

Objective 1:    To understand biological sources of variation in efficiency of feed utilization as quantified by traits such as RFI.

The Kentucky Station is contributing to Objective 1 by extracting RNA from animals demonstrating the extreme range of RFI performance (outlier animals; contributed by other stations) and conducting targeted and genomic expression profiles of selected tissues to determine the effect of RFI phenotype on known and elucidated regulatory and canonical gene networks.

Using a normally vs. sub-optimally growing beef steer model, we completed and compared transcriptomic, targeted mRNA, and targeted protein from liver tissue, using the commercial Bovine GeneChip (liver) and custom WT Btau 4.0 Array (pituitary) microarrays, RT-PCR, and Western blot analyses to compare the expression of genes critical to energy production, mitochondrial mass, amino acid and selenium (selenoprotein) metabolism. We found that sub-optimally growing steers had reduced expression of genes for selenoproteins, enzymes that support selenoprotein synthesis, and increased expression of genes responsible for proline, serine, and ATP synthesis, along with increased mitochondrial mass.

Using a growing heifer model, we found that the form (inorganic, organic, 1:1 blend of inorganic and organic) in which selenium is supplied in mineral-vitamin premixes of finishing diets greatly affects liver transcriptome profiles, with major differences including genes involved with selenoprotein expression, amino acid metabolism, and pathway regulation by neuropeptide Y and glucagon signaling.

We developed reagents for, and identified changes in expression of, mRNA and proteins likely to be responsible for putative changes in hepatic and pituitary metabolism in high vs. low RFI growing cattle.  We will continue our elaboration of bovine gene products (mRNA and protein) in pathways likely to be differentially-expressed in high vs. low RFI beef animals.

Opportunities for training and professional development were provided for four graduate and two undergraduate students from the University of Kentucky and University of Guelph.  The students received training in (and conducted) the experimental design, statistical analyses, bioinformatics analysis, and/or GEO database entry of targeted mRNA/protein and transcriptomic experiments.

University of Nebraska:

Towards achieving the first objective of understanding the biological sources of variation in efficiency of feed utilization, we have sampled and genotyped ~ 750 animals. The animals used in this study were fed 3 different diets (50:50 Alfalfa hay: sweetbran mix, 58% corn silage, 30% distillers and 8% Alfalfa mix, and 70% corn silage and 30% Alfalfa hay mix). Additionally, the animals on the 50:50 Alfalfa hay:sweetbran mix were also evaluated under several other finishing diets with different fat sources. In addition to genotyping and phenotyping the microbiota, individual animal feed intake and performance data were also collected. The microbial community composition of these animals have been evaluated using 16S rRNA sequencing of the V4 variable region with an average depth of 20,000 reads per sample and a minimum of 8,000 reads per sample. The microbial community composition was evaluated using custom pipelines developed in the Fernando lab. The microbial community composition was distinctly different between the 3 diets and clustered separately in the principal coordinate analysis. This was confirmed in the Bray Curtis dissimilarity matrix based PERMANOVA analysis. Phylum level differences were detected between the 3 diets where the diet containing wet distillers displayed decreased Bacteroidetes compared to the other two diets. Additionally, Proteobacteria were lower in the diet containing the 50:50 Alfalfa hay:sweetbran mix. In addition to evaluating diet dependent shifts in the rumen microbial community, we evaluated microbial community shifts within diet for high and low efficiency animals. To this end we compared the microbial community composition of the 25% most efficient and least efficient animals within the 58% corn silage, 30% distillers and 8% Alfalfa mix diet and 70% corn silage and 30% Alfalfa hay mix diet. In both diets, the most efficient animals contained greater abundance of operational taxonomic units (OTUs) belonging to family Prevotellaceae. In low efficiency animals, OTUs belonging to family Lachnospiraceae were high. Additionally, in the 70% corn silage and 30% Alfalfa hay mix diet, several unclassified OTUs were significantly higher in high efficiency animals including BS11 and RFP12. These OTUs that are high in high efficiency animals may be candidate species to develop direct fed microbials. The microbial community of the animals on the 50:50 alfalfa hay:sweetbran mix, when fed different finishing diets containing different fat sources did not show significant microbial community composition differences between the diets. However, the finishing diets were significantly different from the common diet containing 50:50 Alfalfa hay:sweetbran mix.

Towards achieving objective 2 of discovering physiological biomarkers and genetic markers for feed efficiency phenotypes, we are currently performing the genotype by microbiota analysis. Therefore, no data are currently available for this objective.

Short-term outcomes of the Nebraska project include training and professional development, which include a graduate student working on this project taking the short courses in genomic selection offered by Iowa State University. Additionally, the graduate student has attended regional workshops, including the Beef Improvement Federation annual meeting.

In terms of outputs, we have generated genotypic data, performance data, and microbial community data for almost 750 animals. Specific duties have been carried out by individuals or teams using scientific methods to reveal new knowledge and develop new understanding.  We developed esophageal tubing methods that will be used to collect samples that are representative of the rumen microbiota and have a similar microbial community structure to samples collected via the rumen fistula.

University of Tennessee:

The University of Tennessee Institute of Agriculture continues its research examining efficient forage utilization and enhanced reproductive efficiency.  Research goals are to discover new technologies and practices that improve livestock efficiency and sustainability of beef cattle production. Numerous peer-reviewed publications, lectures at invited national society symposia, and grants were produced as a result of these projects.  

Within the last year, the University of Tennessee Institute of Agriculture (UTIA) has made several strides to fulfill the objectives of the W2010 Multistate Research Project.  The W2010 has four major objectives focusing on feed efficiency in beef production systems. 

1. To understand biological sources of variation in efficiency of feed utilization.
2. To discover physiological biomarkers and genetic markers for RFI.
3. To develop EPDs, informed by molecular studies in building multi-trait selection indices and decision-support tools to facilitate selection for improved FE in beef cattle.
4. To develop producer educational programs to enhance technology adoption by the beef industry.

Researchers at this station actively and exclusively participate in objective 1.  As publications are the primary tangible result expected from the project, our research findings were publicized to the academic community through peer-reviewed publications and conference presentations.  Some research findings were brought to classroom teaching. Graduate and undergraduate students were also involved in the research projects. The target audience includes producers, community, industry, commodity production groups, foundations, and other stakeholders involved in beef production.

Two research publications, one invited research talk at a national meeting, and one invited review have been developed from this station in 2015 as a result of the W2010 multistate project.

We continue to work on research pertaining to adaptive mechanisms that promote energy efficiency in grazing beef cows.  Specifically, we continue to progress with understanding molecular mechanisms involved in grazing cattle, growth, and productivity and their effects on feedlot performance. 

Iowa State University

Saatchi, M., J. E. Beever, J. E. Decker, D. B. Faulkner, H. C. Freetly, S. L. Hansen, H. Yampara-Iquise, K. A. Johnson, S. D. Kachman, M. S. Kerley, J. Kim, D. D. Loy, E. Marques, H. L. Neibergs, E. J. Pollak, R. D. Schnabel, C. M. Seabury, D. W. Shike, W. M. Snelling, M. L. Spangler, R. L. Weaber, D. J. Garrick, and J. F. Taylor. 2014. QTL, candidate genes, metabolic and signaling pathways associated with growth, metabolic mid-test weight, feed intake and feed efficiency in beef cattle. BMC Genomics. Under review.

Russell, J. R., N. O. Minton, W. J. Sexten, M. S. Kerley, and S. L. Hansen. 2014. Feedlot performance and diet digestibility of feed efficiency-ranked beef steers fed corn or roughage-based diets and finished with corn or byproduct-based diets. J. Anim. Sci. 92 (Suppl. 2) Abst 589.

Russell, J., E. Lundy, and S. Hansen. 2014. Growth and Carcass Characteristics of Feed Efficiency Sorted Cattle Fed Corn or Roughage-Based Diets and Finished with Corn or Byproduct-Based Diets. Iowa State University Animal Industry Report: 2864.

Montana State University

Boles, J. A., K. S. Kohlbeck, M. C. Meyers, K. A. Perz, K. C. Davis, and J. Thomson. 2015.  The use of blood lactate concentration as an indicator of temperament and its impact on growth rate and tenderness of steaks from Simmental x Angus steers. Meat Sci. 103:68-74.

Lean, Ian, M. Lucy, J. McNamara, B. Bradford, E. Block, J. Thomson, J. Morton, P. Celi, A. Rabiee, J. Santos, W. Thatcher, and S. LeBlanch. 2015. Invited Review: Recommendations for reporting intervention studies on reproductive performance in dairy cattle: Improving design, analysis, and interpretation of research on reproduction. J. Dairy Sci. In Press.

Perz, K., J. Berardinelli, R. Shevitski, J. White, and J. Thomson. 2015. Use of human tri-axial pedometer for measurement of sheep activity. Animal Behavior Science. In review.

The Ohio State University

Yilmaz, A., N. Mohamed, K. A. Patterson,Y. Tang, K. Shilo, M. A. Villalona-Calero, M. E. Davis, X. Zhou, W. Frankel, G. A. Otterson, and W. Zhao.  2014. Clinical and metabolic parameters in non-small cell lung carcinoma and colorectal cancer patients with and without KRAS mutations.  Int. J. Environ. Res. Public Health 2014, 11, 8645-8660;doi:10.3390/ ijerph110908645

Yilmaz, A., N. Mohamed, K. A. Patterson, Y. Tang, K. Shilo, M. A. Villalona-Calero, M. E. Davis, X. Zhou, W. Frankel, G. A. Otterson, H. D. Beall, and W. Zhao.  2014.  Increased NQO1 but not c-MET and Survivin expression in non-small cell lung carcinoma with KRAS mutations.  Int. J. Environ. Res. Public Health 2014, 11, 9491-9502; doi:10.3390/ijerph110909491

Chung, H. Y., Y. C. Choi, and M. E. Davis.  2015.  Associations between genetic variants in the promoter region of the insulin-like growth factor-1 (IGF-1) gene and blood serum IGF-1 concentrations in Hanwoo cattle.  Genet. Mol. Res. 14 (2): 3026-3035.

Hong, Joonki, Duwan Kim, Kyuho Cho, Soojin Sa, Sunho Choi, Younghwa Kim, Juncheol Park, Gilberto Silber Schmidt, Michael E. Davis, and Hoyoung Chung.  2015.  Effects of genetic variants for the swine FABP3, HMGA1, MC4R, IGF2, and FABP4 genes on fatty acid composition.  Meat Sci. 110:46-51.

Choi, Yoonjeong, Michael E. Davis, and Hoyoung Chung.  2015.  Effects of genetic variants in the promoter region of the bovine adiponectin (ADIPOQ) gene on marbling of Hanwoo beef cattle.  Meat Sci. 105:57-62.

Zhang, J., Y. Suh, Y. M. Choi, P. Chen, M. E. Davis, and K. Lee.  2015.  Differential expression of cell cycle regulators during hyperplastic and hypertrophic growth of broiler subcutaneous adipose tissue.  Lipids 50:965-976.

Zhang, J., J. Ahn, Y. Suh, S. Hwang, M. E. Davis, and K. Lee.  2015.  Identification of CTLA2A, DEFB29, WFDC15B, SERPINA1F and MUP19 as novel tissue-specific secretory factors in mouse. PLoS ONE 10(5): e0124962. doi:10.1371/journal.  pone.0124962.

University of California-Davis

Oltjen, J.W. 2014. Criterios para la correcta determinacion del punto de terminacion de los animales en el confinamiento: Ventajas y desventajas del confinamiento, desde el punto de vista del dueño del confinamiento y del dueño de los animales. Proceedings Praderas y Forrajes-XXII Congreso Internacional de Transferencia de Tecnología agropecuaria CEA 2014, Asunción, Paraguay 3-4 November 2014, pp. 41-52.

Oltjen, J. W., and S. A. Gunter. 2015. Managing the herbage utilization and intake by cattle grazing rangelands. Animal Production Science 55:397-410.

Sainz, R. D., and J. W. Oltjen. 2015. Incorporation of a variable maintenance coefficient into calculations of residual feed intake. Canadian Journal of Animal Science vol. 95, DOI: 10.4141/cjas-2015-501.11111111

University of Illinois

Cassady, C., J. Adcock, K. M. Retallick, and D. W. Shike. 2015.  Heifer intake and feed efficiency as indicators of cow intake and efficiency. Midwest Section of Animal Sciences Meeting. Des Moines, IA. J. Anim. Sci. 93 (E-Suppl. 2): 050.

University of Kentucky

Cerny, K. L., L. Anderson, W. R. Burris, M. Rhoads, J. C. Matthews, and P. J. Bridges. 2015. Form of supplemental selenium fed to cycling cows affects systemic concentrations of progesterone, but not estradiol. Theriogenology doi:10.1016/j.theriogenology.2015.10.022.

Liao, S. F., J. A. Boling and J. C. Matthews. 2015. Gene expression profiling indicates an increased capacity for proline, serine, and ATP synthesis and mitochondrial mass, by the liver of steers grazing high vs. low endophyte-infected tall fescue. J. Anim. Sci. 93:1-13. doi:10.2527/jas2015-9193.

Miles, E. D., B. W. McBride, Y. Yang, S. F. Liao, J. A. Boling, P. J. Bridges, and J. C. Matthews. 2015. Glutamine synthetase (GS) and alanine transaminase expression are decreased in livers of aged vs. young beef cows and GS can be up-regulated by 17β-estradiol implants. J. Anim. Sci. 93:4500-4509. doi 10.2527/jas2015-9294.

Cerny, K. L., S. Garbacik, C. Skees, W. R. Burris, J. C. Matthews, P. J. Bridges. 2015. Gestational form of selenium in free-choice mineral mixes affects transcriptome profiles of neonatal calf testis, including those of steroidogenic and spermatogenic pathways. Biological Trace Element Research doi:10.1007/s12011-01500386-4.

Steele, M. A., Schiestel C., O. AlZahal, L. Dionissopoulus, A. H. Laarman, J. C. Matthews, and B. W. McBride. 2015. The periparturient period is associated with structural and transcriptomic adaptations of rumen papillae in dairy cattle. J. Dairy Sci. 98:2583-2595. doi: 10.3168/jds.2014-8640.

2014. C. Matthews, and P. J. Bridges. 2014. NutriPhysioGenomics applications to identify adaptations of cattle to consumption of ergot alkaloids and inorganic versus organic forms of selenium: altered nutritional, physiological and health states? Animal Production Science 54:1594-1604. doi.org/10.1071/AN14274.

Gene Expression Omnibus (microarray datasets) deposited by James C. Matthews

GSE62570 - Affymetrix WT Btau 4.0 Array (version 1) Gene Chip experiment (16 microarrays) associated with “Pituitary Gene Expression Profiles of Growing Beef Steers Grazing High versus Low Endophyte-Infected Tall Fescue Grass”.  James C. Matthews (PI). Released October 23, 2014. 

University of Nebraska

Allison L. Knoell, Christopher L. Anderson, Anna Pesta, Galen Erickson, Terry Klopfenstein, and Samodha C. Fernando.  2015.  Effect of diet on the rumen microbial community composition of growing cattle and the role it plays in methane emissions.  Nebraska 2015 Beef Cattle Report.

Anna C. Pesta, Andrea K. Watson, Robert G. Bondurant, Samodha C. Fernando, and Galen E. Erickson. 2015.  Effects of Dietary Fat Source and Monensin on Methane Emissions, VFA Profile, and Performance of Finishing Steers.  Nebraska 2015 Beef Cattle Report.

Allison L. Knoell, Christopher L. Anderson, Anna Pesta, Galen Erickson, Terry Klopfenstein, Samodha C. Fernando.  2015. Understanding interactions between diet, methane emissions and microbial community composition in growing and finishing beef cattle. Midwest Animal Science Meeting Des Moines, IA (March 16-18, 2015)

University of Tennessee

Barbero, R. P., Malheiros, E. B., Araújo, T. L. R., Nave, R. L. G., Mulliniks, J. T., Berchielli, T. T., Ruggieri, A. C., and Reis, R, A. 2015. Combining Marandu grass grazing height and supplementation level to optimize growth and productivity of yearling bulls. Animal Feed Science and Technology, 209, pp.110-118.

Mulliniks, J. T., Sawyer, J. E., Harrelson, F. W., Mathis, C. P., Cox, S. H., Löest, C. A. and Petersen, M. K., 2015. Effect of late gestation bodyweight change and condition score on progeny feedlot performance. Animal Production Science.

Petersen, M. K., Mueller, C. J., Mulliniks, J. T., Roberts, A. J., DelCurto, T. and Waterman, R. C., 2014. Beef Species Symposium: Potential limitations of NRC in predicting energetic requirements of beef females within western US grazing systems. J. Anim. Sci. 92(7), pp.2800-2808.

Barbero, R., Nave, R. L. G., and Mulliniks, J. T. 2014. Effect of forage species on the rumen microbial population to estimate methane production. ASA, CSSA, and SSSA International Annual Meeting.