Digital Commons Network^™

Grazing Cover Crops As An Alternative To Fallow And The Interaction Between Corn Processing Method And Condensed Distillers Solubles, Alex H. Titlow

Department of Animal Science: Dissertations, Theses, and Student Research

Recently, producers in dryland wheat farming regions have made a shift from the typical winter wheat fallow rotation to a no-till system paired with cover crops. Cover crops have been shown to minimize these problems associated with the conventional fallow and possibly provide a source of forage. A 2-year grazing study was conducted to evaluate forage quality and utilization of cover crops (CC) planted to replace fallow in no-till wheat systems compared to crested wheatgrass pastures (CWP). Hand clipped and diet samples were greater in digestibility and CP for CC compared to CWP. The NDF and ADF content of the …

The Impact Of Genetic Background On Body Temperature Regulation In Beef Cattle During Periods Of Heat And Cold Stress., Jeremy T. Howard

Department of Animal Science: Dissertations, Theses, and Student Research

Cattle are reared in environments that differ and vary greatly in climate, thus the ability to regulate body temperature across multiple environments is essential. However, inherent differences between animals do exist and can influence their response to extreme temperatures. The objectives of the current study were to model the impact of myostatin genotype (MG) on body temperature during heat and cold stress and conduct a genome-wide association study (GWAS) to better understand the genetic basis of body temperature regulation during extreme temperatures.

Crossbred steers and heifers (n= 239) with varying degrees of Piedmontese influence were fed in four groups over …

Beef Cattle Production: Understanding The Effect Of Heifer Development System, Late Gestation Protein Supplementation, And Ovarian Steroidogenic Environment On Productivity, Reproduction, And Longevity, Adam Summers

Department of Animal Science: Dissertations, Theses, and Student Research

Beef cattle longevity is related to reproductive success, which can be influenced by development system and maternal environment. Three experiments were conducted to determine the impact of development system, maternal protein supplementation, and ovarian steroidogenic environment on beef cattle reproduction. Experiment 1 evaluated the effect of heifer development system on heifer performance and reproduction. Heifers developed on corn residue (CR) had reduced BW from prebreeding through pregnancy diagnosis compared with drylot (DL) developed heifers, but there was no difference in reproductive performance. A subset DL and CR heifers were placed in an individual feeding system to …

The Effects Of Social And Environmental Enrichments On Leg Strength And Welfare Of Tomturkeys, Patricia A. Weber

Department of Animal Science: Dissertations, Theses, and Student Research

Two trials (T1, T2) were conducted to determine the effects of enrichment: A) broiler chick addition on early mortality and B) providing environmental enrichments on leg strength and welfare of tom turkeys. Trial 1A utilized 248 1d poults and 8 3d broiler chicks. Four pens of 32 poults were placed for the control. Four pens of 30 poults and two 3d broiler chicks were placed for the trt group. Trial 2A utilized 296 1d poults and 24 3d broiler chicks. Four trts were randomly divided among 16 pens (20 birds/pen). Trt 1 brooders were placed with assistance finding resources. Trt …

Spoilage Of Wet Distillers Grains Plus Solubles When Stored In A Bunker, Jana L. Harding

Department of Animal Science: Dissertations, Theses, and Student Research

Five studies evaluated the impact of spoilage of wet distillers grains plus solubles (WDGS) on nutrient composition, nutrient losses, and cattle performance. Exp. 1 and Exp. 2 utilized barrels to evaluate the ability of various cover treatments to prevent nutrient changes and losses due to spoilage. In Exp. 3, a 140-d barrel study was conducted to mimic bunker storage under ambient temperature but with no precipitation. Barrels were weighed and sampled on 28 day intervals. In Exp. 4, a 130-d finishing study utilized 60 individually-fed steers fed 3 treatments: a dry-rolled corn based diet (control) and 2 diets containing 40% …

Evaluation Of Soybean Hulls And Feed Additives In Finishing Beef Diets, Curtis J. Bittner

Department of Animal Science: Dissertations, Theses, and Student Research

Replacing the amount of corn in finishing diets with ethanol byproducts, such as distillers grains, has been well researched and improves performance. However, research when including soybean hulls (SBH) in feedlot finishing diets with distillers grains is limited. Two feedlot experiments were conducted to evaluate the effects of SBH on animal performance and carcass characteristics in finishing diets. Dietary concentrations of SBH used were 0, 12.5, 25, and 37.5% of diet DM, in both experiments. Modified distillers grains plus solubles was included in the diet at 25% for Exp.1 while Exp. 2 contained an inclusion level of 40% wet distillers …

Intestinal Flow Of Microbial Protein And Rumen Undegradable Protein In Cattle Fed Corn Distillers Grains And Solubles, With Emphasis During Lactation, Ezequias Castillo Lopez

Department of Animal Science: Dissertations, Theses, and Student Research

Metabolizable protein (MP) is the true protein absorbed by the intestine, supplied by rumen undegradable protein (RUP) and microbial crude protein (MCP). This research was focused on evaluating the effect of dried distillers grains with solubles (DDGS) on the nature and supply of MP, with emphasis during lactation.

Experiment 1 evaluated the use of DNA markers and the effects of fermentation time and DDGS on rumen microbial growth

in vitro. Treatments were 1) CONTROL, 0% DDGS; 2) 20% DDGS replacing corn; 3) 20% DDGS replacing soybean meal and 4) 20% DDGS replacing corn and soybean meal. Results indicate that …

The Effect Of Dam Parity On Progeny Growth Performance, Passive Immunity, And Gastrointestinal Microbiota, Erin E. Hinkle

Department of Animal Science: Dissertations, Theses, and Student Research

Previous research has shown that parity (P) 4 progeny have greater weaning weights and decreased microbial diversity compared to P1 progeny. Three experiments were conducted to evaluate litter performance, passive immunity, and fecal microbiota among P1 and P3 dams and their progeny. In experiment 1, 56 P1 and 49 P3 dams and their progeny’s litter and growth performance, immunoglobulin (IgG and IgA) concentrations, and gut microbiota were evaluated. In experiment 2, 48 pigs per P were selected to determine growth performance, immunoglobulin (IgG and IgA) concentrations, and gut microbiota. In experiment 3, 8 dams per P were selected. At birth, …

Alternative Fabrication Methods For The Beef Carcass, Justine J. Hosch

Department of Animal Science: Dissertations, Theses, and Student Research

To fabricate heavier beef carcasses alternative fabrication methods for the chuck and round were evaluated. Carcasses (364 to 386 kg) were selected for forequarter (n=32) and hindquarter (n=30) evaluation. Forequarter breaks at the third/fourth and fifth/sixth rib, with the rib beginning at the sixth/seventh rib, were processed into whole muscles. Bone, lean trim, fat, and muscles were weighed and Longissimus dorsi (LD) steaks were subject to Warner-Bratzler Shear Force (WBS). Both subprimals had over 60% lean yield and no differences among WBS results (P=0.49, 0.39, respectively). To evaluate effects of modifying the chuck/rib break short rib …

Utilization Of Corn Condensed Distillers Solubles And Forages In Management Systems For The Cow-Calf Enterprise, Jason M. Warner

Department of Animal Science: Dissertations, Theses, and Student Research

Of the annual expenses necessary to maintain a beef cow, feed and forage are the greatest and most variable. Thus, nutrition programs for cow-calf operations must be developed using economical feedstuffs that optimize cowherd performance. The corn dry-milling industry provides several feedstuffs that are often the most economical sources of energy and protein, but considerations for storage and handling are necessary. Two experiments evaluated an alternative form of storing corn condensed distillers solubles (CCDS) by applying to grass hay windrows before baling. Round bales were treated with either 0 or 20% (Exp. 1); or 0, 16, and 32% (Exp. 2) …

Hepatic Mitochondrial Efficiency In Lines Of Mice Differing In Feed Intake, Thomas Murphy

Department of Animal Science: Dissertations, Theses, and Student Research

Selection was practiced for high (MH) and low (ML) heat loss using direct calorimetry to create lines of mice differing in feed intake per unit BW (FI/BW). Selection occurred for both criteria in each of 3 replications (R); an unselected control (MC) was also maintained in each replicate. A total of 25 generations of selection was practiced; the 9 lines are presently maintained without selection. As a percentage of MC, mice of MH and ML lines differed in heat loss and FI/BW by 56 and 34%, respectively, when selection ceased. The 218 male mice measured in the present study came …

Mechanism And Control Of Beef Toughening During Retail Display In High Oxygen Modified Atmosphere Packages, Lasika S. Senaratne

Department of Animal Science: Dissertations, Theses, and Student Research

This research was conducted to elucidate the mechanism and factors (diet, aging time, antioxidant level, and retail display time) affecting beef toughening in retail display under high oxygen atmosphere packages (HiOx-MAP; 80% O₂ and 20% CO₂). In the first study, effects of HiOx-MAP on color and lipid stability of beef m. longissimus lumborum steaks from yearlings fed corn or 30% wet distillers grains plus soluble (WDGS) diets supplemented with (150 mg/kg) or without (0 mg/kg) AGRADO-PLUS (AG) antioxidants were studied. Steak color-shelf life was extended (P < 0.0001) by HiOx-MAP compared to oxygen permeable film packages (PVC-OW). Steaks from corn+AG-supplemented cattle had (P ≤ 0.05) less discoloration and lower lipid oxidation levels …

Genomic Analysis Of Characteristics In Swine Contributing To Sow Longevity, Julie Kathleen Tart

Department of Animal Science: Dissertations, Theses, and Student Research

Selection for improved sow lifetime reproductive longevity is of growing importance to swine producers due to recent increases in sow culling rates. Traditional selection results in minimal response due to low heritability and late expression of the trait; incorporation of DNA markers into selection programs could be a more economically viable tool and improve lifetime reproductive performance.

In order to assess the relationship between markers and reproductive longevity, 967 gilts from two maternal crossbred lines were evaluated for age at puberty (AP), litter size traits, and number of successful parities (SP). Females were culled only for death, unsoundness, or reproductive …

Treatment With Or Elimination Of Vascular Endothelial Growth Factor A (Vegfa) Results In Altered Mrna Abundance Of Undifferentiated Spermatogonia Niche, Renewal And Differentiation Factors, Kevin M. Sargent

Department of Animal Science: Dissertations, Theses, and Student Research

Vascular Endothelial Growth Factor A (VEGFA) and its receptors are important for vascular development in the testis. Roles of VEGFA have been proposed in undifferentiated spermatogonia where proangiogenic isoforms are suggested to promote their self-renewal while antiangiogenic isoforms stimulate their differentiation. Thus, we treated male rats in vivo (perinatally with IP injections from P0-P2) with different VEGFA isoforms or an antibody to VEGFAxxxb (antiangiogenic isoforms) to determine if this would affect testis morphogenesis, expression of genes regulating the spermatgonial stem cell (SSC) niche and genes that regulate cell survival. Testis morphogenesis with VEGFA164 (1mg) isoform treatment increased cord area, reduced …

Nutrient Mass Balance And Performance Of Feedlot Cattle Fed Barley Based Diets In Large Pens In Western Canada, Erin M. Hussey

Department of Animal Science: Dissertations, Theses, and Student Research

Three separate large pen commercial feeding trials with approximately 9,000 heifers with either eight or ten reps/treatment were conducted at a Western Feedlots Ltd.- High River, a commercial feedyard near High River, AB, Canada. For all three experiments, Near Infrared Spectroscopy (NIRS) was used to segregate feed barley. In Exp. 1, barley was segregated based on digestible energy (DE) content as predicted by NIRS and heifers were fed low or high DE barley, or a 50:50 blend of the two. Feeding low DE barley improved weight gain, dry matter intake (DMI), and mortality; with little effect on carcass composition compared …

Utilization Of Corn Residue, Winter Range, Or Dry Lot In Beef Heifer Development Systems, Stetson P. Weber

Department of Animal Science: Dissertations, Theses, and Student Research

Post-weaning heifer development systems that maximize reproductive efficiency and reduce input costs associated with feed is beneficial for cow/calf producers. Two research experiments were conducted to evaluate the effect of post-weaning development systems in beef heifers. In Exp. 1 heifers were developed on corn residue (CR), or dry lot (DL). Heifers developed in DL had increased BW after winter treatment until breeding. Both heifer groups were similar in percent of heifers cycling, AI conception, AI pregnancy, and final pregnancy diagnosis. A subset of AI pregnant heifers were blocked by weight and stratified by winter development system and individually fed using …

Effects Of Feeding Insect-Protected Corn And Corn Residue To Cattle, And Evaluation Of Distillers Grains Storage When Mixed With Crop Residue On Cattle Performance, Barry Weber

Department of Animal Science: Dissertations, Theses, and Student Research

Research has been conducted on genetically modified corn fed to livestock since the introduction of insect resistant hybrids. While the overwhelming conclusion of these trials demonstrate nutritional equivalency to corn from non-transgenic hybrids, the introduction of new transgenes and combinations of resistance traits necessitates continued evaluation of genetically modified corn hybrids. Expansion of the ethanol industry has resulted in the increased availability of co-products for use as a livestock feed, as well as an increase in crop residues that offer unique opportunities for use by cattle producers. A finishing trial was conducted with corn and corn silage from MON 89034, …