Animal Sciences Commons^™

The Relationship Between Marbling, Superoxide Dismutase, And Beef Tenderness, Nicolas J. Herrera, Emery K. Wilkerson, Katherine I. Domenech-Perez Perez, Felipe A. Ribeiro, Michael D. Chao, Chris Calkins

Nebraska Beef Cattle Reports

This study was conducted to evaluate the relationships between animal oxidative status (as indicated by superoxide dismutase [SOD] activity) to marbling and beef tenderness. Prime and Select-grade strip loins were selected and aged for 2, 7, 14, 21, and 28 days for Warner Bratzler shear force, Troponin-T, and SOD activity. Results showed that meat exhibiting higher levels of marbling had lower shear force values and thus were more tender. Low-marbled samples tended to have a greater tenderness response to aging. The effect of oxidative stress, however, was not evident in this study as SOD values were similar. Although the effects …

Evaluation Of Corn Distillers Solubles On Finishing Steer Performance, Benjamin H. Hansen, Curtis J. Bittner, Bradley M. Boyd Boyd, F. Henry Hilscher, Jim C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

A finishing study was conducted to evaluate the effects of feeding 0, 8, 16, or 20% corn distillers solubles (CDS), as well as the effects of feeding a combination of 16% CDS and 20% wet distillers grains plus solubles (WDGS) to replace a blend of dry-rolled and high-moisture corn on finishing steer performance. As inclusions of CDS increased, ADG linearly increased and F:G linearly decreased. Feeding value of CDS at 20% inclusion was determined to be 147% compared to the corn blend. The addition of WDGS resulted in a decrease in DMI with similar ADG, resulting in a decrease in …

Effect Of Myoglobin State On Color Stability Of High Pressure Processed Ground Beef, Jhinuk Gupta, Chad G. Bower, George A. Cavender Cavender, Gary A. Sullivan

Nebraska Beef Cattle Reports

High pressure processing, a non-thermal pasteurization technique, can reduce E. coli in beef but the use is limited due to discoloration of raw beef after high pressure processing. Different states of myoglobin have inherently different color stability. The objective of this study was to determine the impact of myoglobin state on color stability of raw beef patties treated with high pressure processing. Modified atmosphere packaging (high oxygen-oxymyoglobin, carbon monoxide-carboxymyoglobin), vacuum packaging (deoxymyoglobin) or added potassium ferricyanide (metmyoglobin) treatments were used to prepare patties with desired myoglobin states. Color was measured (CIE L*, a*, b*) before and after high pressure processing …

Effect Of Ingredients And Packaging On Color Of High Pressure Processed Ground Beef, Jhinuk Gupta, Chad G. Bower, George A. Cavender Cavender, Gary A. Sullivan

Nebraska Beef Cattle Reports

High pressure processing is a non-thermal pasteurization technique to control pathogens, like E. coli. However, color changes in raw beef induced by processing restrict high pressure processing’s use within the beef industry. The objectives of this study were to investigate the effects of adding curing agents (nitrite) and packaging with or without reducing compounds (ascorbic acid/erythorbate) on color retention in high pressure processed ground beef. High pressure processing resulted in a detrimental effect on the color of the beef patties for all treatments. Lightness and yellowness increased and redness decreased after high pressure processing. The effect remained the same throughout …

Effects Of Production System On Cow And Calf Performance, Shelby E. Gardine, Jason M. Warner, Robert G. Bondurant Bondurant, F. Henry Hilscher, Karla H. Jenkins, Galen E. Erickson, Terry J. Klopfenstein

Nebraska Beef Cattle Reports

Limited traditional forage resources have prompted interest for alternative cow-calf production systems. This study evaluated the effects of two winter cow-calf production systems (cornstalk grazing and dry-lot feeding) on cow-calf performance in a summer-calving, intensively managed cowherd at two locations. Grazing cow-calf pairs on cornstalks resulted in similar or lower ending BW of cows and lower ADG of calves when compared to cow-calf pairs wintered in the dry-lot. A partial budget of incorporating winter cornstalk grazing into an intensive production system suggests that cows wintered on cornstalks may be $137 more profitable compared to cows wintered in the dry-lot.

Effects Of Production System And Post-Weaning Management On Finishing Performance And Carcass Characteristics Of Steer And Heifer Calves, Shelby E. Gardine, Bradley M. Boyd, Curtis J. Bittner Bittner, F. Henry Hilscher, Karla H. Jenkins, Galen E. Erickson, Terry J. Klopfenstein

Nebraska Beef Cattle Reports

This study evaluated the effects of cow-calf production system and post-weaning management on finishing performance and carcass characteristics of steer and heifer calves. Calves that were wintered on cornstalks prior to weaning had lighter initial BW compared to calves that were wintered in the dry-lot; however, final BW and carcass weight were similar between treatments. Post-weaning management was either adapting calves to a finishing diet following weaning or feeding a grower diet prior to the finishing phase. When harvested at similar back fat, calves that were fed a grower diet for 76 days prior to the finishing phase had 71 …

Evaluation Of Protein From Distillers Grains In Finishing Diets On Nutrient Digestibility, Zachary E. Carlson, Jana L. Gramkow, Hannah C. Wilson Wilson, Melissa L. Jolly-Breithaupt, Galen E. Erickson, Jim C. Macdonald, Matt K. Luebbe

Nebraska Beef Cattle Reports

A metabolism trial was conducted to evaluate protein from modified distillers grains plus solubles (MDGS) in finishing diets on nutrient digestibility and ruminal fermentation characteristics. Isolated protein from corn was not different than MDGS for dry matter, organic matter, or neutral detergent fiber digestibility. However, steers fed MDGS tended to have lower total tract organic matter digestibility compared to corn and protein from corn. Protein had greater total tract organic matter and starch digestibility than MDGS. Protein from corn did not contribute towards the lower digestibility of MDGS. Protein is more easily digestible than the other components in distillers grains …

Production Of High-Quality Beef–The Nebraska Advantage, Chris R. Calkins

Nebraska Beef Cattle Reports

Here is a clear description of the Nebraska Advantage in producing high-quality beef: the right genetics, numerous pastures, a multitude of cattle, great water resources, locally-grown corn, the availability of ethanol byproducts for feed, and young cattle that grow fast, with sufficient marbling and subcutaneous fat to ensure tender, flavorful, beef. The science of beef quality supports this production system. The state supports its citizens and agriculture through the University of Nebraska and the Nebraska Department of Agriculture, augmenting the infrastructure. If one could invent an ideal place to produce high-quality beef, it would look much like Nebraska! The impact …

Potential Variation In Determination Of Longissimus Muscle Area In Carcasses From Heifers Fed With Or Without Zilpaterol Hydrochloride, Chris R. Calkins, Jenna J. O'Daniel, Govindarajan Konda Naganathan Naganathan, Kellen B. Hart, Katherine I. Domenech-Perez, T.B. Schmidt

Nebraska Beef Cattle Reports

This study was conducted to evaluate some sources of potential variation in determination of longissimus muscle area between the 12th and 13th ribs of carcasses from heifers fed with or without zilpaterol hydochloride. Cross sections of the rib-loin were taken cranial to the 11th rib and caudal to the 13th rib, about 3–4 millimeters thick at 90 degrees perpendicular to the long axis of the longissimus muscle. Potential variation of longissimus muscle area can arise from the natural variation of muscle size when cutting between the 12th and 13th ribs (up to 9%). Deviation in cutting perpendicular to the long …

Impact Of Feeding Distillers Grains With Or Without Oil Removal As Well As Supplemental Corn Oil On Nutrient Digestibility By Finishing Cattle, Jordan E. Burhoop, Melissa L. Jolly-Breithaupt, Jana L. Gramkow Gramkow, Matthew K. Luebbe, Jim C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

A digestion trial was conducted to determine the effects of the removal of corn oil from modified distillers grains plus solubles (MDGS) and the impact of supplemental corn oil on finishing cattle nutrient digestion. Four treatments were evaluated: a corn control diet (CON), 40% de-oiled MDGS (DO MDGS), or 38% de-oiled MDGS plus 2% corn oil (MDGS + Oil) formulated to equal the fat content of FF MDGS, or 40% full fat MDGS (FF MDGS). Treatment differences were observed for digestibility of dry matter, organic matter, and fiber, but not for fat. When oil was added to de-oiled MDGS, digestibility …

Effects Of Late Gestation Supplementation, Synchronization, And Creep Feeding In A Spring Calving Beef Herd In The Nebraska Sandhills, Devin Broadhead, L. A. Stalker, Jacki A. Musgrave Musgrave, Richard N. Funston

Nebraska Beef Cattle Reports

Supplementation during winter grazing increased cow BW and BCS but had no effect on reproduction or calf performance, thus increasing production costs without increasing returns. Using a CIDR for estrus synchronization in a herd with existing acceptable reproductive performance did not increase cow pregnancy rate or advance calving date. Feeding creep feed to calves is an effective means of increasing weaning BW which resulted in increased live and carcass weight. Under the conditions of this study, when additional feed and price slide for heavier calves was considered, feeding creep feed did not result in added profits.

Field Evaluations Of Insecticide Modes Of Action Classes For Control Of Horn Flies In Nebraska, David J. Boxler, Gary J. Brewer, Richard N. Funston Funston, Jacqueline A. Musgrave

Nebraska Beef Cattle Reports

Insecticides of different Mode of Action (MoA) classes were tested for their ability to reduce horn fly populations on cattle in Nebraska pastures between 2009 and 2016. Macrocyclic lactone products were the most efficacious, reducing horn fly numbers by an average of 93% over ten location years of testing. Organophosphate and pyrethroid MoA products, tested in 7 and 12 location years, reduced fly numbers by 75% and 73%. Classes tested only once were METI (88% reduction) and a combination of organophosphate + pyrethroid (64%).

Evaluation Of Revalor-Xh For Beef Heifers Fed Different Days On Feed, Robert G. Bondurant, Marshall N. Streeter, Galen E. Erickson Erickson, James C. Macdonald, Matt K. Luebbe

Nebraska Beef Cattle Reports

Heifers were treated with either no implant, an initial implant of Revalor-200 and re-implanted with Revalor-200, or Revalor-XH and assigned to one of four serial slaughter harvests at 151, 165, 179, and 193 days on feed to determine the effects on feedlot performance and carcass characteristics. Implanting heifers increased final BW, ADG and HCW while decreasing marbling score and improving feed efficiency compared to non-implanted heifers. Increasing days on feed decreased ADG while increasing feed efficiency, HCW, fat thickness, marbling score, and calculated yield grade. By increasing HCW sold, implanting revenue can be maximized, assuming added risk for YG discounts.

Effect Of Supplementation During The Breeding Season On A May-Calving Herd In The Nebraska Sandhills, Alicia C. Lansford, Jacki A. Musgrave, Richard N. Funston Funston

Nebraska Beef Cattle Reports

Females in their first and second breeding season received either a 32% crude protein (DM) supplement or no supplement throughout the breeding season. Supplementation did not affect heifer BW, BCS, and pregnancy rate at pregnancy diagnosis. Supplementation impacted primiparous cow BW and BCS at pregnancy diagnosis, but did not affect pregnancy rates. Calf birth weight and dystocia rates were unaffected by supplementation for both heifers and primiparous cow. Calves nursing supplemented dams were heavier at weaning. Greater supplementation may be needed to affect pregnancy rate.

Development Of An Avian Index Of Biological Integrity For Kentucky Wetlands, Kaitlyn Kelly

Online Theses and Dissertations

Bird communities are frequently used as bioindicators to assess environmental conditions, including in wetland habitats. I developed an avian index of biological integrity (IBI) for wetlands of Kentucky as an intensive assessment method to supplement an existing rapid assessment method used in regulatory programs. Birds are useful indicators because they are sensitive to environmental changes, abundant in various landscapes, occupy higher trophic levels, and can be sampled in a cost-effective manner. Breeding bird point count data from 103 sites were used to calculate a set of 49 avian community metrics. Avian metrics were tested for correlation with independent landscape, hydrology …

Variation In Mass And Wing Loading Of Nestling American Kestrels: Possible Effects Of Nestling Behavior And Adult Provisioning Behavior, Doug Mitchell

Online Theses and Dissertations

Among birds, the rapid growth rates of altricial young help reduce mortality by reducing the amount of time spent in the nest. However, in species where a high degree of maneuverability and speed is required (i.e. aerial insectivores), it is important that nestlings not gain excess weight. Nestlings in some species must attain an efficient wing loading just prior to fledging to facilitate mobility for hunting and evading predators. My objective was to examine the mass of nestling American Kestrels (Falco sparverius) during the mid- to late nestling period and specifically to determine the possible effects of attaching small lead …

The Horse: A Driving Force For The Lifestyle Of Grooms, Nicole Foright

Online Theses and Dissertations

The fundamental components of co-occupational relationships between humans and animals and their impact on occupational identity is an area for exploration in the study of occupation. Evaluating the lives of persons whose daily occupations involve working with animals contributes to the exploration of human-animal co-occupations. The aim of this research was to understand the lifestyle of International 4-in-Hand Combined Driving grooms and their symbiotic relationship with horses. This qualitative descriptive study used three methods for data collection and triangulation: semi-structured interviews, observation, and photographs, from 4 participants who served as gatekeepers understanding the culture surrounding the driving community. The data …

Including Phenotypic Causal Networks In Genome-Wide Association Studies Using Mixed Effects Structural Equation Models, Mehdi Momen, Ahmad Ayatollahi Mehrgardi, Mahmoud Amiri Roudbar, Andreas Kranis, Renan Mercuri Pinto, Bruno D. Valente, Gota Morota, Guilherme J.M. Rosa, Daniel Gianola

Department of Animal Science: Faculty Publications

Background: Phenotypic networks describing putative causal relationship among multiple phenotypes can be used to infer single-nucleotide polymorphism (SNP) effects in genome-wide association studies (GWAS). In GWAS with multiple phenotypes, reconstructing underlying causal structures among traits and SNPs using a single statistical framework is essential for understanding the entirety of genotype-phenotype maps. A structural equation model (SEM) can be used for such purpose.

Methods: We applied SEM to GWAS (SEM-GWAS) in chickens, taking into account putative causal relationships among body weight (BW), breast meat (BW), hen-house production (HHP), and SNPs. We assessed the performance of SEM-GWAS by comparing the model results …

Physiological And Behavioural Response Of Two Dairy Cows’ Genotypes During Summertime In The Central Region Of Chile, Rodrigo A. Arias, Camila Herrera, Rafael Larraín, Fernando González, Terry L. Mader, Alejandro Velásquez

Department of Animal Science: Faculty Publications

Heat stress has been recognized as a serious problem in dairy farms. The study goal was to assess the effects of climatic conditions on physiological and behavioral responses of dairy cows in Central Chile. Data of tympanic temperature (TT), panting score, respiration rate (RR), and shade utilization of cows from two genotypes, Holstein (H) and Holstein x Montbeliarde (HM), were collected twice per day (AM/PM) during three periods of the summer season in Central Chile. Moreover, three thermal comfort indices: Comprehensive climate index (CCI), temperature humidity-index (THI), and adjusted THI were estimated using meteorological data. The hour of each day …

Big Data Analytics And Precision Animal Agriculture Symposium: Machine Learning And Data Mining Advance Predictive Big Data Analysis In Precision Animal Agriculture, Gota Morota, Ricardo V. Ventura, Fabyano F. Silva, Masanori Koyama, Samodha C. Fernando

Department of Animal Science: Faculty Publications

Precision animal agriculture is poised to rise to prominence in the livestock enterprise in the domains of management, production, welfare, sustainability, health surveillance, and environmental footprint. Considerable progress has been made in the use of tools to routinely monitor and collect information from animals and farms in a less laborious manner than before. These efforts have enabled the animal sciences to embark on information technology-driven discoveries to improve animal agriculture. However, the growing amount and complexity of data generated by fully automated, high-throughput data recording or phenotyping platforms, including digital images, sensor and sound data, unmanned systems, and information obtained …

The Influence Of Fat And Hemicellulose On Methane Production And Energy Utilization In Lactating Jersey Cattle, O. R. Drehmel, T. M. Brown-Brandl, J. V. Judy, S. C. Fernando, P. S. Miller, K. E. Hales, Paul J. Kononoff

Department of Animal Science: Faculty Publications

Feeding fat to lactating dairy cows may reduce methane production. Relative to cellulose, fermentation of hemicellulose is believed to result in less methane; however, these factors have not been studied simultaneously. Eight multiparous, lactating Jersey cows averaging (±SD) 98 ± 30.8 d in milk and body weight of 439.3 ± 56.7 kg were used in a twice-replicated 4 × 4 Latin square to determine the effects of fat and hemicellulose on energy utilization and methane production using a headbox-type indirect calorimetry method. To manipulate the concentration of fat, porcine tallow was included at either 0 or 2% of the diet …

Predictive Ability Of Genome-Assisted Statistical Models Under Various Forms Of Gene Action, Mehdi Momen, Ahmad Ayatollahi Mehrgardi, Ayyub Sheikhi, Andreas Kranis, Llibertat Tussell, Gota Morota, Guilherme J. M. Rosa, Daniel Gianola

Department of Animal Science: Faculty Publications

Recent work has suggested that the performance of prediction models for complex traits may depend on the architecture of the target traits. Here we compared several prediction models with respect to their ability of predicting phenotypes under various statistical architectures of gene action: (1) purely additive, (2) additive and dominance, (3) additive, dominance, and two-locus epistasis, and (4) purely epistatic settings. Simulation and a real chicken dataset were used. Fourteen prediction models were compared: BayesA, BayesB, BayesC, Bayesian LASSO, Bayesian ridge regression, elastic net, genomic best linear unbiased prediction, a Gaussian process, LASSO, random forests, reproducing kernel Hilbert spaces regression, …

Linkage Disequilibrium In Brazilian Santa Inês Breed, Ovis Aries, Amanda Botelho Alvarenga, Gregori Alberto Rovadoscki, Juliana Petrini, Luiz Lehmann Coutinho, Gota Morota, Matthew L. Spangler, Luis Fernando Batista Pinto, Gleidson Giordano Pinto Carvalho, G. B. Mourao

Department of Animal Science: Faculty Publications

For genomic selection to be successful, there must be sufficient linkage disequilibrium between the markers and the causal mutations. The objectives of this study were to evaluate the extent of LD in ovine using the Santa Inês breed and to infer the minimum number of markers required to reach reasonable prediction accuracy. In total, 38,168 SNPs and 395 samples were used. The mean LD between adjacent marker pairs measured by r² and |D′| were 0.166 and 0.617, respectively. LD values between adjacent marker pairs ranged from 0.135 to 0.194 and from 0.568 to 0.650 for r² for |D′| …

Estimates Of Genomic Heritability And Genome-Wide Association Study For Fatty Acids Profile In Santa Inês Sheep, G. A. Rovadoscki, S. F. N. Pertile, A. B. Alvarenga, A. S. M. Cesar, F. Pertille, J. Petrini, V. Franzo, W. V. B. Soares, G. Morota, Matthew L. Spangler, L. F. B. Pinto, G. G. P. Carvalho, D. P. D. Lanna, L. L. Coutinho, G. B. Mourao

Department of Animal Science: Faculty Publications

Background: Despite the health concerns and nutritional importance of fatty acids, there is a relative paucity of studies in the literature that report genetic or genomic parameters, especially in the case of sheep populations. To investigate the genetic architecture of fatty acid composition of sheep, we conducted genome-wide association studies (GWAS) and estimated genomic heritabilities for fatty acid profile in Longissimus dorsi muscle of 216 male sheep.

Results: Genomic heritability estimates for fatty acid content ranged from 0.25 to 0.46, indicating that substantial genetic variation exists for the evaluated traits. Therefore, it is possible to alter fatty acid profiles through …

Effect Of Differing Ingredients And Packaging Technologies On The Color Of High-Pressure Processed Ground Beef, Jhinuk Gupta, Chad G. Bower, Gary Sullivan, George A. Cavender

Department of Animal Science: Faculty Publications

High-pressure processing (HPP) is a nonthermal pasteurization technique to control pathogens, like Escherichia coli. However, color changes in raw beef induced by HPP restrict its use within the beef industry. ­e objectives of this study were to investigate the effects of adding curing agents (nitrite) and packaging with or without reducing compounds (ascorbic acid/erythorbate) on color retention in high-pressure processed ground beef. Color was measured (CIE L*a*b*) before HPP and on days 3, 7, 12, 14, 19, and 21 after HPP. Statistical analysis (SAS GLIMMIX) was run to identify the main effects of adding curing agents, packaging, and …

The Impact Of Truncating Data On The Predictive Ability For Single-Step Genomic Best Linear Unbiased Prediction, Jeremy T. Howard, Thomas A. Rathje, Caitlyn E. Bruns, Danielle F. Wilson-Wells, Stephen D. Kachman, Matthew L. Spangler

Department of Animal Science: Faculty Publications

Simulated and swine industry data sets were utilized to assess the impact of removing older data on the predictive ability of selection candidate estimated breeding values (EBV) when using single-step genomic best linear unbiased prediction (ssGBLUP). Simulated data included thirty replicates designed to mimic the structure of swine data sets. For the simulated data, varying amounts of data were truncated based on the number of ancestral generations back from the selection candidates. The swine data sets consisted of phenotypic and genotypic records for three traits across two breeds on animals born from 2003 to 2017. Phenotypes and genotypes were iteratively …

Do Stronger Measures Of Genomic Connectedness Enhance Prediction Accuracies Across Management Units?, Haipeng Yu, Matthew L. Spangler, Ronald M. Lewis, Gota Morota

Department of Animal Science: Faculty Publications

Genetic connectedness assesses the extent to which estimated breeding values can be fairly compared across management units. Ranking of individuals across units based on best linear unbiased prediction (BLUP) is reliable when there is a sufficient level of connectedness due to a better disentangling of genetic signal from noise. Connectedness arises from genetic relationships among individuals. Although a recent study showed that genomic relatedness strengthens the estimates of connectedness across management units compared with that of pedigree, the relationship between connectedness measures and prediction accuracies only has been explored to a limited extent. In this study, we examined whether increased …

Fecal Microbiota Transplantation Is Associated With Reduced Morbidity And Mortality In Porcine Circovirus Associated Disease, Megan C. Niederwerder, Laura A. Constance, Raymond R. R. Rowland, Waseem Abbas, Samodha C. Fernando, Megan L. Potter, Maureen A. Sheahan, Thomas E. Burkey, Richard A. Hesse, Ada G. Cino-Ozuna

Department of Animal Science: Faculty Publications

Porcine circovirus associated disease (PCVAD) is a term used to describe the multifactorial disease syndromes caused by porcine circovirus type 2 (PCV-2), which can be reproduced in an experimental setting through the co-infection of pigs with PCV-2 and porcine reproductive and respiratory syndrome virus (PRRSV). The resulting PCVAD-affected pigs represent a subpopulation within the co-infected group. In co-infection studies, the presence of increased microbiome diversity is linked to a reduction in clinical signs. In this study, fecal microbiota transplantation (FMT) was investigated as a means to prevent PCVAD in pigs co-infected with PRRSV and PCV-2d. The sources of the FMT …

Generation Of An Equine Biobank To Be Used For Functional Annotation Of Animal Genomes Project, E. N. Burns, M. H. Bordbari, M. J. Mienaltowski, V. K. Affolter, M. V. Barro, F. Gianino, G. Gianino, E. Giulotto, T. S. Kalbfleisch, S. A. Katzman, M. Lassaline, T. Leeb, M. Mack, E. J. Muller, J. N. Macleod, B. Ming-Whitfield, C. R. Alanis, T. Raudsepp, E. Scott, S. Vig, H. Zhou, J. L. Petersen, R. R. Bellone, C. J. Finno

Department of Animal Science: Faculty Publications

The Functional Annotation of Animal Genomes (FAANG) project aims to identify genomic regulatory elements in both sexes across multiple stages of development in domesticated animals. This study represents the first stage of the FAANG project for the horse, Equus caballus. A biobank of 80 tissue samples, two cell lines and six body fluids was created from two adult Thoroughbred mares. Ante-mortem assessments included full physical examinations, lameness, ophthalmologic and neurologic evaluations. Complete blood counts and serum biochemistries were also performed. At necropsy, in addition to tissue samples, aliquots of serum, ethylenediaminetetraacetic acid (EDTA) plasma, heparinized plasma, cerebrospinal fluid, synovial …

Energy Balance And Diurnal Variation In Methane Production As Affected By Feeding Frequency In Jersey Cows In Late Lactation, J. V. Judy, G. C. Bachman, T. M. Brown-Brandl, S. C. Fernando, K. E. Hales, P. S. Miller, R. R. Stowell, P. J. Kononoff

Department of Animal Science: Faculty Publications

Methane (CH₄) production of ruminants typically increases with increased dry matter intake (DMI). However, few studies have observed the effects of feeding multiple times a day and its effects on diurnal variation in CH₄ production and energy balance in late-lactation dairy cattle. A study using headbox-style indirect calorimetry and 12 multiparous (225 ± 16.2 d in milk; mean ± SD) lactating Jersey cows was conducted to determine the effects of feeding twice daily on diurnal variation in CH₄ production and total energy balance. A crossover design with 14-d periods (10 d of adaption and 4 d …