Dairy Science Commons^™

The Effect Of Diet Formulations Containing Different Protein Sources On Energy And Nitrogen Utilization In Lactating Jersey Cows, Kortney Ann Harpestad

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

It is well understood that lactating dairy cows require metabolizable protein (MP) for milk yield and milk protein synthesis. Diets with conventional feed sources like corn and soybean meal (SBM) may not sufficiently meet all MP and amino acid (AA) requirements so supplementation with more rumen undegradable protein (RUP) rich feeds or rumen-protected AA can be fed to support animal performance. The growth trajectory of biofuels has resulted in dramatic increases in the production of feeds like heat treated soybean meal (HTSBM). While the chemical composition of this product is understood, there is a need to better understand how HTSBM …

Methane Mitigation And Its Effects On Energy Utilization In Lactating Dairy Cattle, Shan C. Sherwood

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

Improved methane (CH₄) mitigation strategies are needed to achieve the greenhouse gas emission goals of the dairy industry. The first experiment was conducted to evaluate the effects of feeding black cumin (Nigella sativa) seed oil and acetate (BCA) on CH₄ production and whole-animal energy utilization. Twelve dry Jersey cows were used in a 2-period crossover design study with 28d periods. The BCA treatment was compared to a control diet with corn oil. Both BCA and corn oil were added to the base diet as a top dress. Results from this study did not show any …

Precision Feeding Methods To Increase Nitrogen And Energy Utilization In Lactating Dairy Cows, Chloe Emily Moss Harris

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

The environmental and economic costs of overfeeding N to dairy cattle are a challenge in today’s dairy industry. Two studies were conducted to address new opportunities for precision feeding N, which is a strategy where producers strive to feed cows the precise amount of N and amino acids that meet their individual requirements.

The objective of the first study was to evaluate the effects of supplementing a rumen protected methionine (RPM) product via automatic milking system (AMS) concentrate on milk protein yield in lactating dairy cows. Fifty-one cows were randomly assigned to control (no RPM) or treatment groups. Milk yield …

Examining Factors Of Variance In Energy Metabolism Of Dairy Cattle, Addison L. Carroll

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

Variation is thought to occur in the use of dietary energy for production in dairy cattle. First, variance can be observed when new methane mitigation strategies are fed resulting in increased H₂ output potentially resulting in downstream effects on estimates of heat production via the Brouwer (1965) equation. Therefore, in chapter 3 a review was created to systematically describe the mathematics and theory behind the Brouwer equation, and rederive a heat production equation to integrate H₂ production. Results indicate heat production using the classical Brouwer equation (1965) relative to the rederived equation resulted in an overestimation of heat …

Feeding Dried Distillers' Grains With Solubles To Lactating Dairy Cattle: Whole Animal Energy Utilization And Manure Biogas Production, Grant Michael Fincham

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

When DDGS are fed to lactating dairy cattle, the observed response in energy supply, milk production, and methane production varies among studies. One potential reason for these observed discrepancies is the nature of the diet formulation itself. Furthermore, little research has been conducted to examine how dietary changes can affect dairy cattle manure composition and methane production in an anaerobic manure digester. In order to gain a better understanding of these topics, we conducted two experiments. The first experiment was conducted to test how the manipulation of lactating dairy cattle diets affects energy utilization, milk production, methane production, and manure …

The Evaluation Of Feed Additives On Reducing Enteric Methane Production From Cattle, Reba L. Colin

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

Environmental sustainability can be positively impacted by the inclusion of feed additives to reduce enteric methane production from cattle. Methane production can be affected by feed additives that either alter the rumen environment or act as methanogenesis inhibitors. A reduction in methane from cattle can contribute to meeting carbon neutrality.

A metabolism study was conducted to evaluate Alga 1.0, a product containing bromoform, fed to cattle to evaluate the effects on gas emissions. Treatments were (0, 69, or 103 g/d Alga 1.0) fed in a corn-based diet. Headbox-style indirect calorimeters were used to measure gas emissions. Feeding Alga 1.0 linearly …

Factors Affecting Forage Quality And The Subsequent Response In Production And Energy Metabolism In Lactating Jersey Cows, Kassidy Kate Buse

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

Forage quality is the potential of a forage to produce a production response in animals. Because of how essential they are in dairy cattle rations, forages can have major influence on the behavior and production of dairy cattle. In experiment 1, the effect of forage fragility on the rumen environment and digestibility was evaluated. Increasing the inclusion of a less fragile forage led to greater rumen retention time, which resulted in lower rumen pH and greater NDF digestibility. Experiment 2 evaluated the effects of diets high in either corn silage or alfalfa haylage supplemented with either corn- or soybased protein …

Supplemental Table 1. Influence Of The Count Of Positive Days On Dmi, Milk Yield, Milk Fat, Milk Protein, And Pregnancy Rate, Addison Carroll, Paul J. Kononoff

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

Response

Intercept

Devstarch

Devfat

DevNDF

DevPro

BIC

Impact Of Increasing Level Of Milk Production On Cow And Calf Behavior And Performance In The Nebraska Sandhills, Selby L. Boerman

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

Selection for increased milk production across the United States has resulted in variable cow and calf production responses. Better understanding of calf nursing and grazing behaviors may provide opportunities to help estimate how milk and grazed forage intake influence variability in calf performance. In a 2-yr study, cow-calf pairs (n = 65) were equipped with neck collars containing global positioning system (GPS) units to validate the efficacy of high-frequency GPS data to accurately identify calf nursing events and grazing behavior. Data were collected during 3-wk tracking periods during early lactation (calf age 65.4 ± 10.0 d; EARLY) and late …

The Impact Of Plant Cell Wall Lignin On Energy Utilization In Lactating Jersey Cows, Jason D. Stypinski

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

Fiber from forages comprises a significant proportion of dairy cattle rations and by extension, it contributes largely to the energy concentration of the diet. While the proportion of fiber in the diet is important, the composition of fiber is probably more important as the different constituents of this fraction vary in their contributions to the nutritive value of the feed. Lignin has been described as an important factor limiting the digestion of NDF, reducing intake, and compromising milk production. Although lignin’s effects on these responses have been well characterized, the literature lacks data on the use of indirect calorimetry to …

Using Indirect Calorimetry To Investigate Feeding Value Of Byproducts For Lactating Dairy Cattle: Canola Meal And Dried Distillers' Grains And Solubles, Mickayla Ann Marie Myers

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

Byproducts have played a major role in dairy nutrition by providing a cheaper protein and fiber source, while also utilizing a product that would otherwise be waste from the human perspective. Use of byproducts in the dairy industry should allow for continued and overall increases in production and efficiency of the dairy industry. Two of the more popular byproducts in the dairy industry today are dried distillers' grains and solubles and canola meal.

In the first experiment, 12 multiparous lactating Jersey cows were used evaluate the feeding value of dried distillers grains and solubles (DDGS) or canola meal. A replicated …

Methane From Lactating Dairy Cattle: Studies For Mitigation, Diurnal Variation, And Role In Energy Metabolism, Jared Vern Judy

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

Reducing methane production in dairy cattle has received an increased interest due to environmental concerns associated with its potency as a greenhouse gas. Methane represents lost energy in cattle and reduction may increase animal efficiency and productivity. Experiment 1 evaluated strategies of mitigating methane production in lactating dairy cattle with inclusion of dried distillers grains and solubles (DDGS), DDGS with added corn oil, and DDGS with added calcium sulfate and effects on energy and nitrogen balance. Inclusion of DDGS, corn oil, and calcium sulfate, increased DMI and milk yield. Methane production was reduced with addition of corn oil …

The Effects Of Supplemental Rup In Corn Silage Growing Diets And Rup Digestibility Of Corn Silage, The Utilization Of Aggressive Implant Protocols, And The Effect Of Inoculate On Corn Silage And High Moisture Corn, Colton Ray Oney

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

Three experiments evaluated the effect of implant strategies on feedlot performance and carcass characteristics of crossbred steers and Holstein steers. Final BW, ADG, and G:F were not different between implant strategies in Exp. 1 and 2. The utilization of more aggressive implant strategies has minimal impact on both feedlot and carcass performance of cross breed steers.

Four experiments evaluated the effects of supplemental RUP in corn silage growing diets and RUP content and RUP digestibility of corn silage. Exp. 1, supplemented five concentrations of RUP to growing calves consuming a corn silage diet. As supplemental RUP increased ADG and ending …

Effect Of Fat And Fiber On Methane Production And Energy Utilization In Lactating Dairy Cows, Olivia Rose Drehmel

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

Due to rising concerns of greenhouse gases and that ruminants are the largest livestock methane producers, an emphasis has been put on developing methane mitigation strategies to reduce methane emissions in ruminants. Other than reducing methane, maximizing the energy utilization of cattle is also important for producer’s overall productivity and profitability.

In the first experiment, fat or cellulose was added to fiber isolated from dried distiller’s grains and solubles. Isolated NDF residue from an in vitro setting was fermented 1) alone (control); 2) with feed grade corn oil at 20%; or 3) with cellulose powder microcrystalline at 20% using the …

Efficiency Of Energy Utilization And Fecal Mineral Excretion In Holstein And Jersey Dairy Cows, Gabriel Garcia Gomez

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

Eight multiparous Holstein and 8 Jersey dairy cows were used to complete energy balance trials designed to determine the effect of breed on the production and energy efficiency of milk, and energy partitioning. A repeated switchback design was used to compare the effect of cow breed. Diets consisted of 24.5% corn silage, 18.4% alfalfa hay, 6.9% grass hay, with either 22.9% rolled corn and 14.8% soybean meal (CON) or 8.95% rolled corn and 28.8% reduced fat distillers grains (RFDDGS) DM-basis. Diets were offered ad libitum for a 28 d adaptation period and 95% ad libitum for a 4 d collection …

The Effects Of Hmtba (2-Hydroxy-4-Methylthio-Butanoic Acid) Supplementation On Ruminal Microbial Crude Protein Synthesis And Community Structure In Dairy Cattle, Chad James Robert Jenkins

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

Metabolizable protein (MP) is protein that reaches the small intestine and is available for absorption and utilization by the cow. Dairy rations may be limited in the supply of MP essential to meeting the demands of milk synthesis, however as much as half of the MP flowing to the small intestine may be attributed to microbial origins and is referred to as microbial CP (MCP). Experiment 1 utilized a technique in which DNA was used as a microbial marker to estimate the concentration of bacterial CP (BCP) in the solid and liquid portions of rumen digesta. Rumen digesta was sampled …

Energy Content Of Reduced-Fat Dried Distillers’ Grains And Solubles For Lactating Dairy Cows And Effects On Energy And Nitrogen Balance, Alison J. Foth

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

Eight Holstein and 8 Jersey multiparous, lactating cows were used to complete 56 energy balances to determine the energy content of reduced-fat distillers grains and solubles (RFDDGS). A repeated switchback design was used to compare treatments with and without RFDDGS. Diets consisted of 24.2 % corn silage, 18.4 % alfalfa hay, 6.94 % brome hay with either 22.9 % rolled corn and 14.8 % soybean meal (Control), or 8.95 % rolled corn, 28.8 % RFDDGS, and 0 % soybean meal (Co-P; DM basis). The inclusion of RFDDGS did not affect (P = 0.86) DMI averaging 21.4 ± 0.53 kg …

Study Of The Innovative Self-Powered Sensor Based Smart Wireless Identification And Tracking Tag For Production Agriculture Application, Kumud Dhakal

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

A prototype smart animal ear tag has been developed to meet the United States Department of Agriculture (USDA) animal disease traceability requirement. This novel ‘Smart Tag’ is a self–powered device capable of complete animal identification and tracking. Information on animal health, breeding and vaccination records can also be locally stored and retrieved from these small, economical and securely accessible wireless tags. These smart tags are capable of self-organizing into wireless ad-hoc networks for data reporting and retrieval. This work presents study of the distance coverage of a ‘Smart Tag’ and a cost-benefit analysis of ‘Smart Tag’ implementation. The mean distance …

Effect Of Brown Midrib Corn Silage And Dried Distillers Grains Plus Solubles On Lactational Performance And Nitrogen Utilization By Dairy Cows, Hugo A. Ramirez

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

Thirty six Holstein cows, four ruminally cannulated, (mean ± SD, 111 ± 35 DIM; 664 ± 76.5 kg BW) were used in replicated 4×4 Latin squares to investigate the effects of brown midrib (bm3) and conventional (DP) corn silages, and the inclusion of dried distillers grains plus solubles (DDGS) on milk production and N utilization. In each 28 d period cows were assigned to one of four treatments: DP plus 0% DDGS (CON); bm3 plus 0% DDGS (BMR); DP corn silage plus 30% DDGS (DP+DG); and bm3 plus 30% DDGS (BMR+DG). Dry matter intake was greater (P < 0.01) for cows consuming bm3 (25.8 VS 24.4 ± 0.47 kg), likewise for DDGS (24.3 and 25.9 ± 0.47 kg/d for 0 and 30%). Compared to DP hybrid, NDFD was higher (P < 0.01) for bm3 (32.5 VS 38.1 ± 1.79%). There was a hybrid × DDGS interaction (P < 0.01) for total concentration of volatile fatty acids (VFA) and rumen pH as the highly digestible treatment BMR+DG resulted in the highest VFA and the lowest pH. Milk yield was not affected by treatment and averaged 30.6 ± 1.09 kg/d. Milk protein yield (MPY) was greater (P < 0.01) for bm3 and DDGS treatments. There was a hybrid by DDGS interaction (P = 0.02) for milk fat yield (MFY) resulting in 1.03, 1.08, 0.84 and 0.78 ± 0.045 kg/d for DP, BMR, DP+DG and BMR+DG. Fat corrected milk (FCM) was affected by DDGS (P < 0.01) and averaged 30.0 and 26.4 ± 1.0kg/d (0% and 30% inclusions). Urinary N excretion was similar among treatments; however fecal N was lower (P = 0.03) for diets containing bm3 corn silage which caused lower (P = 0.02) manure N. These results indicate that bm3 corn silage and DDGS increase DMI, NDFD and MPY; however high inclusion of corn silage with 30% DDGS reduces FCM. Nitrogen excretion was reduced when cows consumed bm3.

Distillers' Grains With Solubles For Feedlot Cattle: Finishing Performance, Lipid Metabolism, And Ethanol Greenhouse Gas Balance, Virgil R. Bremer

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

Previous University of Nebraska feedlot research trials have characterized the feed value of wet distillers grains plus solubles (WDGS). These trials were summarized with meta-analysis methodology and indicated the feed value of WDGS interacts with corn processing type, cattle age (calf-fed or yearling), and inclusion level. Two steer finishing studies and a metabolism study were conducted to understand the impact of different lipid sources in WDGS on WDGS feed value. A biphasic lipid extraction procedure was developed to analyze feed samples from these trials that was more effective than Goldfisch ether extraction at lipid analysis of byproduct feds. These trials …