Large or Food Animal and Equine Medicine Commons^™

Science-Based Regulation Of Pharmacological Substances In Competition Horses, Jacob Machin

Theses and Dissertations--Toxicology and Cancer Biology

Current testing methodologies within equine forensic toxicology focus on arbitrary thresholds and zero-tolerance policy. Modern analytical chemistry’s limits of detection are low enough that oftentimes femtogram-per-milliliter amounts of a substance can readily be identified in both blood and urine of a horse. For most pharmacologically relevant compounds, these concentrations have no relevance to pharmacological effect. It is therefore crucial that testing methodologies to determine appropriate thresholds and cut-offs be developed that are driven by biological activity rather than arbitrary limits of detection. This dissertation looks to address this by suggesting a system of calculated Effective Plasma Concentrations by which a …

The Surveillance Of Gastrointestinal Parasitic Nematodes Of Northwest Arkansas Dairy Cattle Using Traditional And Genetic Parasitological Identification Procedures, Eva M. Wray

Graduate Theses and Dissertations

Traditional and genetic parasitological identification procedures were compared using naturaland artificial nematode parasite infections in Holstein steer calves. The traditional parasitological procedures measured fecal egg counts, coprocultures with subsequent larval collection and adult nematodes collected at necropsy. The genetic identification procedures measured ITS-2 sequences extracted from different stages of nematode development: raw feces, concentrated nematode eggs, third stage larvae and adults. The primary nematodes observed were Cooperia oncophora, Cooperia punctata and Ostertagia ostertagi. The traditional techniques were not significantly different from one another, while the genetic sequencing showed variation amongst the different procedures. The raw feces sequences showed the most …

The P-Glycoprotein Repertoire Of The Equine Parasitic Nematode Parascaris Univalens, Alexander P. Gerhard, Jürgen Krücken, Emanuel Heitlinger, I. Jana I. Janssen, Marta Basiaga, Sławomir Kornaś, Céline Beier, Martin K. Nielsen, Richard E. Davis, Jianbin Wang, Georg Von Samson-Himmelstjerna

Maxwell H. Gluck Equine Research Center Faculty Publications

P-glycoproteins (Pgp) have been proposed as contributors to the widespread macrocyclic lactone (ML) resistance in several nematode species including a major pathogen of foals, Parascaris univalens. Using new and available RNA-seq data, ten different genomic loci encoding Pgps were identified and characterized by transcriptome-guided RT-PCRs and Sanger sequencing. Phylogenetic analysis revealed an ascarid-specific Pgp lineage, Pgp-18, as well as two paralogues of Pgp-11 and Pgp-16. Comparative gene expression analyses in P. univalens and Caenorhabditis elegans show that the intestine is the major site of expression but individual gene expression patterns were not conserved between the two nematodes. In P. …

Metagenomic, Viral And Host Genetic Analyses Of Congenital Tremor In Pigs, Kylee Sutton

School of Biological Sciences: Dissertations, Theses, and Student Research

The Pestivirus genus contains several viral species having a major impact on the livestock species. While there were only four major pestiviral species for a time, recent metagenomic sequencing approaches identified additional species, such as atypical porcine pestivirus (APPV). Congenital tremor was first identified almost a hundred years ago and since still has an impact on swine health. There are two main types of congenital tremor, type A and B, with type A congenital tremor further subcategorized based on causative agent. Until recently, type A-II congenital tremor did not have a known cause. Recent viral sequencing of affected samples, including …

The Efficacy Of Extended-Release Eprinomectin For The Reduction Of Horn Flies, Face Flies, And Fecal Egg Counts Of Parasitic Nematodes In Replacement Beef Heifers, Sophia F. Landers

Animal Science Undergraduate Honors Theses

The purpose of this study was to evaluate the efficacy of extended-release eprinomectin against horn flies, face flies, and fecal egg counts of parasitic nematodes in crossbreed replacement beef heifers. Fifty-four heifers were randomly placed into three treatment groups (N=18 heifers/treatment). Group 1 was administered the labeled dosage of extended-release eprinomectin on day 0. Group 2 acted as the negative control. Group 3 received the anthelmintic injection once a quarter of the heifers in the group reached the threshold treatment level for horn flies (N=200 flies/animal; day 41). Nematode infections were measured via fecal egg counts while horn and face …

Use Of Diatomaceous Earth And Copper Oxide Wire Particles To Control Gastrointestinal Nematodes In Lambs, Olivia Jones

Animal Science Undergraduate Honors Theses

Abstract

Anthelmintic resistance (AR) urges alternatives to control gastrointestinal nematodes (GIN). Copper oxide wire particles (COWP) are more efficacious when used with other dewormers and little is known on efficacy of diatomaceous earth (DE) to control gastrointestinal parasites. The objective was to examine the effects of DE and COWP on GIN control. Katahdin lambs (n = 32; ~150 d of age; 25.0 ± 1.8 kg) were randomly assigned to receive: 1) DE fed at an estimated 2% dry matter intake (with the assumption of moderate consumption of bermudagrass forage and provided supplement), 2) 1g COWP, 3) both 2% DE and …

Evaluation Of Anthelmintic Therapies In A Fall Calving Beef Cowherd, Laine Zammit

Graduate Theses and Dissertations

Internal parasitism inevitability prompts economic loss in beef cattle production by decreasing growth performance and reproductive traits. Today, the most widely used class of anthelmintic used to treat parasitism, is the macrocyclic lactone. Many studies have conflicting results on the efficacy of macrocyclic lactones (ML) efficacy against internal parasitism. The objective of this study was to evaluate the effectiveness of moxidectin and eprinomectin, two of the MLs, on cow performance. Multiparous fall calving, crossbred beef cows (n = 106) were allocated randomly to 1 of 3 anthelmintic treatments: 1) Negative control (CON), in which cows did not receive an anthelmintic, …

Effects Of A Vitamin And Mineral Bolus On Beef Heifer Feedlot Performance, Feeding Behavior, Carcass Characteristics, And Liver Mineral Concentrations, Kacie L. Mccarthy, Sarah R. Underdahl, Carl R. Dahlen

Department of Animal Science: Faculty Publications

Crossbred beef heifers (n = 23; initial body weight [BW] = 370 ± 12 kg) housed at the North Dakota State University Beef Cattle Research Complex in Fargo, North Dakota, were used to evaluate the effects of a 250-d slow-release vitamin and mineral bolus on feedlot performance, feeding behavior, carcass characteristics, and liver mineral concentrations. Heifers were assigned to one of two treatments: 1) received no supplemental mineral or vitamin (CON, n = 12 or 2) received two boluses on day 0 (minimum of 3,740 mg Ca, 16,456 mg Mg, 112 mg Na, 11,220 mg Cu, 2,995 mg I, …

Effect Of Conventional Or High Protein Dry Distillers Grains Plus Solubles In Either Dry- Rolled Or Steam- Flaked Corn Based Diets On Finishing Performance Of Steers, Lauren A. Ovinge, L.J. Mcphilips, B.M. Boyd, Galen E. Erickson

Nebraska Beef Cattle Reports

A 2 × 3 factorial finishing study evaluated feeding 0 or 30% high protein distillers grains or conventionally produced distillers in either steam- flaked or dry- rolled corn based diets. Feeding conventional distillers grains in dry rolled corn based diets resulted in improved feed conversion, with no difference between high protein distillers grains as compared to conventional DDGS when included in dryrolled corn diets. In steam flaked corn- based diets, feeding high protein distillers and conventional distillers tended to increase feed conversion. Feeding conventional distillers or high protein distillers grains resulted in greater DMI and ADG as compared to diets …

Growth And Performance Of Terminal Sired Calves Grazing Range Or Meadow Pasture, Robert L. Ziegler, Tonya L. Meyer, Jacki A. Musgrave, J. C. Macdonald, J. Travis Mulliniks, Rick N. Funston

Nebraska Beef Cattle Reports

Multiparous dams were assigned to be bred by artificial insemination or natural service to bulls with terminal traits. Additionally, the cow- calf pairs grazed upland range or sub- irrigated meadow from June 1 to weaning in November. Two weeks aft er weaning, calves entered the feedlot as calffeds. Natural service range calves had the lightest weaning weights, final live weights, and hot carcass weights. Additional days on feed may be required for natural service range calves to reach similar body weights and carcass characteristics as other treatments. Average daily gain and feed conversion was improved in calves that grazed range …

Evaluation Of Masters Choice Corn Silage On Growing Steer Performance, Jiehua Xiong, Bradley M. Boyd, Levi Mcphillips, Kyle Vosburgh, Galen E. Erickson

Nebraska Beef Cattle Reports

A growing study evaluated three corn silage hybrids on growing steer performance. Th e three hybrids were: a conventional hybrid- Farm Choice (CON) commonly grown in Eastern Nebraska which served as the control, Masters Choice hybrids MCT6365 RIB (MC1) selected to improve fi ber and starch digestion and MCT6733 GT3000 (MC2) that has been selected to improve fi ber digestion in cattle. Relative to CON, feeding hybrid MC1 resulted in similar DMI, but numerically increased ADG which significantly improved F:G compared to CON. Feeding MC2 led to greater DMI, similar ADG, and poorer (greater) F:G compared to CON. Feeding Masters …

Evaluating Syngenta Enogen Feed Corn Silage Or Grain On Growing Beef Cattle Performance, Mckenna M. Brinton, Bradley M. Boyd, F. Henry Hilscher, Levi J. Mcphillips, J. C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

A growing trial was conducted to evaluate Syngenta Enogen Feed Corn containing an alpha amylase enzyme trait compared with commercially available corn without the amylase enzyme trait on growing cattle performance characteristics. Corn was harvested as either corn silage or dry corn, and corn silage was further harvested with kernel processing or not. Th e treatment design was a 2×2+2 factorial with 2 hybrids of silage, kernel processed or not, and then a 40% dryrolled corn and hay growing diet as Syngenta Enogen Feed Corn or control corn. No interactions were observed between silage hybrids and kernel processing. Cattle fed …

Comparing March And May Calving Systems In The Nebraska Sandhills, Mckay R. Erickson, Devin L. Broadhead, J. A. Musgrave, Rick N. Funston

Nebraska Beef Cattle Reports

Three production years for March and May calving, Red Angus- based cows and their off spring from the Gudmundsen Sandhills Laboratory (GSL), Whitman, NE, were evaluated. Steer progeny were evaluated through harvest and carcass data collected. Calf birth body weight (BW) and breeding BW were greater for May calves vs. March; however, adjusted weaning BW was greater for March calves. Pregnancy rates, weaning rates, calving interval, calving difficulty, and calf vigor were similar between calving systems. Udder score was greater for March cows. Compared with March calf- fed steers, May calf- fed steers had greater hot carcass weight (HCW), longissimus …

Combined Analysis On The Effects Of Late Gestation Supplementation In A Spring Calving Beef Herd, Devin L. Broadhead, Kathy Hanford, Matthew C. Stockton, Jacki A. Musgrave, R. A. Funston

Nebraska Beef Cattle Reports

Data were compiled from 4 independent studies conducted over 13 years in the Nebraska Sandhills. Th is combined analysis evaluated the effects of late gestation supplementation on cow and calf productivity in a spring calving herd. Cows wintered on dormant range, sub- irrigated meadow or corn residue. Late gestation supplementation improved pregnancy rates regardless of supplement amount or over winter treatment. Supplement did not affect cow body weight and condition score. Calves born to cows fed supplement had greater weaning weights regardless of when they were weaned.

Evaluation Of Commercial Genomic Tests For Maternal Traits In Crossbred Beef Cattle, Mckay R. Erickson, J.R. Tait, R. A. Funston

Nebraska Beef Cattle Reports

DNA samples were collected from beef heifers born at the Gudmundsen Sandhills Laboratory and analyzed with a genomic test. Phenotypic data from these females were compiled and used in a regression analysis to evaluate the utility of these genomic scores as predictors for phenotypic outcomes. Th e genomic score for birth body weight (BW) was signifi cantly associated with animal birth BW. Th e genomic score for heifer pregnancy was not a statistically significant predictor of actual pregnancy. Neither dam age or the genomic score for stayability were significant predictors of actual reproductive longevity.

Efficacy Of A Second Injection Of Prostaglandin F2Α In Yearling Beef Heifers Following Previous Estrus Synchronization, Mckay R. Erickson, Kenneth C. Ramsay, R. Funston

Nebraska Beef Cattle Reports

Angus- based, yearling beef heifers were utilized to determine the effects of administering a second prostaglandin F2α (PGF; Lutalyse, Zoetis Animal Health, Parsippany, NJ) injection to heifers who did not previously respond to estrus synchronization. All heifers were exposed to a melengestrolacetate (MGA)- PGF protocol. Following PGF injection, heifers were observed for estrus (estrus detection patches rubbed) for 3 d and inseminated. Heifers who did not show signs of estrus were placed with fertile bulls. Aft er 3 d with bulls, heifers with greater than 50% of the rub- off coating removed from estrus detection aids were considered to have …

Effect Of Gnrh Injection At - 72 H In Mga- Pgestrus Synchronization Protocol, Mckay R. Erickson, Dan Kelly, Doug O’Hare, T.L. Meyer, R. Funston

Nebraska Beef Cattle Reports

Yearling beef heifers from 2 locations were synchronized with melengestrol acetate (MGA)- prostaglandin F2α (PGF) fi xed time AI (TAI) protocol. At PGF administration 72 h before AI, heifers were randomly assigned to receive either 0 or 5 μg gonadotropinreleasing hormone (GnRH). Th e administration of 5 μg GnRH at PGF did not increase estrus activity or improve TAI pregnancy rates at either location (Location 1, 56% (GnRH) vs. 57%; Location 2, 59% (GnRH) vs. 53%). Administering GnRH at PGF increased (74% vs. 63%) pregnancy rates for heifers inseminated during a follow- up heat detection period at one location. A …

Effect Of Age Of Dam On Heifer Progeny Performance, Joslyn K. Beard, J. A. Musgrave, Kathy Hanford, Rick N. Funston, J. Travis Mulliniks

Nebraska Beef Cattle Reports

Cattle records were gathered and evaluated over a 12- yr period to investigate how cow age impacts heifer progeny growth and reproductive performance. Cow records from March and May calving herds, were categorized into young, moderate, and old groups based on their age at calving each year in the herd. Heifer calves born to young cows had lighter body weight at birth and adjusted 205- d BW than heifers from moderate and old cows. Heifer pre-breeding BW and pregnancy determination BW were not influenced by dam age. However, age of dam does impact the percentage of heifers to reach puberty …

Evaluation Of Level Of Milk Potential On Nutrient Balance In 2- And 4- Year- Old May- Calving Range Cows Grazing Sandhills Upland Range, J. Travis Mulliniks, Don C. Adams

Nebraska Beef Cattle Reports

A modeling study evaluated the effects of milk production level on nutrient balance in May- calving cows grazing Sandhills upland range during the breeding season. Forage quality of upland range peaks in June and steadily declines in July until November. With timing of forage quality decline and increasing nutrient demands due to lactation, cows were in a negative energy balance in late June and early July prior to deficiency of metabolizable protein. Supplementation to meet energy deficiencies in June and July and MP deficiencies in July with distiller grains that is high ruminally undegradable protein and high fiber energy may …

Evaluation Of Rumen Undegradable Protein Sources Fed In An Organic Production System, Elizabeth A. Schumacher, Galen E. Erickson, F. Henry Hilscher, Levi J. Mcphillips, Zac E. Carlson, Mary E. Drewnoski, Jim C. Macdonald, Terry J. Klopfenstein

Nebraska Beef Cattle Reports

Fifty- eight Holstein steers with an initial body weight of 469 lb were fed 1 of 5 dietary treatments containing different rumen undegradable protein (RUP) sources: control with no supplemental protein, field peas, field peas plus fish meal, soybean meal, and SoyPass, a treated soybean meal high in RUP. These protein sources replaced corn in a base diet of 65% dry rolled corn, 30% alfalfa haylage, and 5% supplement in order to balance for metabolizable protein (MP). Th e objective of this study was to compare how rumen undegradable protein sources that can be found in organic production systems affect …

Table Of Contents 2020 Nebraska Beef Cattle Report

Nebraska Beef Cattle Reports

Cow/Calf

Evaluation of Level of Milk Potential on Nutrient Balance in 2- and 4- Year- Old May- Calving Range Cows Grazing Sandhills Upland Range............................ 5

Effect of Age of Dam on Heifer Progeny Performance ........................... 8

Effect of GnRH Injection at - 72 h in MGA- PG Estrus Synchronization Protocol.................................. 10

Efficacy of a Second Injection of Prostaglandin F2α in Yearling Beef Heifers Following Previous Estrus Synchronization ....................... 12

Evaluation of Commercial Genomic Tests for Maternal Traits in Crossbred Beef Cattle ..................................... 14

Combined Analysis on the Effects of Late Gestation Supplementation in a Spring Calving Beef Herd .................................................... 16 …

Comparison Of Rumen Undegradable Protein Content Of Conventional And Organic Feeds, Elizabeth A. Schumacher, Galen E. Erickson, Hannah C. Wilson, J. C. Macdonald, Andrea K. Watson, Terry J. Klopfenstein

Nebraska Beef Cattle Reports

Knowledge of a feed ingredient’s protein content and degradability is important in formulating diets for growing cattle. However, there are limited data on protein composition and digestibility of feeds produced in an organic production system. Two studies were conducted using an in situ mobile bag procedure to compare feeds raised in organic and conventional production systems for rumen undegradable protein (RUP) content and digestibility. No differences were observed for RUP content between organic or conventional sources for dehydrated alfalfa, field peas, or expeller pressed soybean meals. Solvent extracted soybean meals were lower in RUP content than expeller pressed soybean meals. …

Effect Of Conventional Or High Protein Dry Distillers Grains Plus Solubles In Either Dry- Rolled Or Steam- Flaked Corn Based Diets On Amount And Site Of Nutrient Digestion, Lauren A. Ovinge, Mitch M. Norman, Hannah C. Wilson, Kaylee E. Wheeler, Galen E. Erickson

Nebraska Beef Cattle Reports

A 2 × 3 factorial metabolism study using 6 ruminally and duodenally cannulated heifers evaluated the site and amount of nutrient digestion when feeding high protein dry distillers grains plus solubles (DDGS) or conventionally produced DDGS at 30% inclusion compared to feeding no distillers in either dry- rolled or steam- flaked corn diets. Apparent total tract starch digestibility was unaffected by distillers treatment in SFCbased diets, but decreased from 95.1% to 92.0% when DDGS was added to DRC diets, and further decreased to 88.7% for HiPro diets. Dry matter and OM digestibilities were lower types of when either DDGS diets …

Evaluation Of Rup Content Of Nexpro Dried Distillers Grains Plus Solubles And Their Effect On Growing Calf Performance In Corn Silage Based Diets, Aksel R. Wiseman, Zachary E. Carlson, Levi J. Mcphillips, Galen E. Erickson, Andrea K. Watson, Scott L. Tilton

Nebraska Beef Cattle Reports

A growing study was conducted to evaluate the effect of supplementing NexPro, a high- protein dried distillers grains plus solubles (DDGS) from the FluidQuip MSC post- fermentation separation process, in a corn- silage based diet and to determine the rumen undegradable protein (RUP) content of NexPro. Three test proteins (NexPro, SoyPass, and soybean meal) and 4 inclusion levels (4.5, 9, 13.5, and 18%) were evaluated against a common control (0% test protein). Th ere were no differences in dry matter intake among treatments. Increasing inclusion of NexPro resulted in improved feed conversion and daily gain. SoyPass and soybean meal supplementation …

Forage Production And Calf Gains When Grazing Oats Following Corn Harvest, Mckenna M. Brinton, Benjamin H. Hansen, Kristen M. Ulmer, Zachary E. Carlson, F. Henry Hilscher, Mary E. Drewnoski, Jim C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

A 4 yr. study was conducted to evaluate forage yield and grazing potential of double cropped annual forages following corn silage or high- moisture corn harvest. An irrigated field in a corn- soybean rotation was split in half and harvested as either corn silage or high- moisture corn, and crops were sampled to determine any effects on subsequent yield due to cover and grazing. Over the four years, steers grazing oats aft er corn silage harvest gained an average of 2.35 lb/d, while those grazing corn residue and oats aft er high- moisture corn harvest averaged 1.28 lb/d. Average oat …

Economics Of Yearling Systems, Terry J. Klopfenstein, Mary E. Drewnoski, James C. Macdonald, Andrea K. Watson, Jay Parsons

Nebraska Beef Cattle Reports

Economic analyses were conducted to estimate the effect of management decisions on profitability of yearling production systems. Three reported experiments were analyzed where rate of winter gain and length of summer grazing were variables. Corn stalk grazing with distillers grains supplement is quite economical. Winter gains of 1.5 to 2.0 lb/day were more profitable, aft er grass or aft er feedlot, than winter gains less than 1 lb/ day. Yearlings compensated for lower winter gains while on grass, but those gaining more in the winter gained better in the feedlot and produced heavier final weights. The analyses do not show …

Evaluation Of The Water Footprint Of Beef Cattle Production In Nebraska, Tyler J. Spore, Mesfin Mekonnen, Christopher M.U. Neale, Andrea K. Watson, James C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

Data were compiled on feed usage to model the amount of water needed to produce beef in typical Nebraska production systems. Production systems where cows were wintered on corn residue utilized 18% less water than systems utilizing native range as a wintering source, because of water allocations. Therefore, the water footprint (gallons of water required to produce one pound of boneless meat) was decreased by 18%. In addition, increasing the dietary inclusion of distillers grains from 0% to 40% decreased the water footprint in the finishing phase by 29%, again based on water allocation. Utilizing corn residue and distillers grains …

Evaluation Of Ankom F58 Filter Bags Compared To Dacron Bags And Beakers For Analysis Of Acid Detergent Fiber, Braden C. Troyer, Hannah C. Wilson, James C. Macdonald

Nebraska Beef Cattle Reports

Feed and fecal samples were analyzed to compare three methods of determining acid detergent fiber. Each sample was weighed into both Dacron and Ankom F58 fiber bags and then analyzed using an Ankom fiber analyzer. Results were then compared to the Van Soest beaker method. Ankom F58 bags helped reduce washout of small particles associated with Dacron bags, but fecal samples needed to be incubated in detergent for an extended amount of time to isolate acid detergent fiber material. Utilizing a technique that produces correct acid detergent fiber values is important for producers because these values are used as a …

Effect Of Supplemental Protein And Glucogenic Precursors On Digestibility And Energy Metabolism, Tasha M. King, Joslyn K. Beard, Mitch M. Norman, Hannah C. Wilson, Jim C. Macdonald, J. Travis Mulliniks

Nebraska Beef Cattle Reports

A metabolism study was conducted to evaluate the impact of increasing levels of glucogenic precursors on diet digestibility and acetate clearance. Four supplementation strategies containing 0, 30, 40, and 70 g of supplemental glucogenic potential were supplied to a basal diet of bromegrass hay. Addition of glucogenic potential in the form of rumen undegradable protein improved dry matter, organic matter, and acid detergent fiber digestibility efficiency of acetate utilization in growing lambs fed moderate- quality hay. However, no additive effect of supplementing propionate salts and rumen undegradable protein were observed in this study. Th is would suggest that rumen undegradable …

Evaluation Of Green Grass As A Feed Ingredient In Beef Finishing Rations And Impact On Cattle Performance, Carcass Characteristics, And Fatty Acid Profiles In Meat, Mitchell M. Norman, Nicolas A. Bland, Bradley B. Boyd, Briana B. Conroy, Andrea K. Watson, Galen E. Erickson, Chris Calkins

Nebraska Beef Cattle Reports

A finishing study utilizing 240 crossbred steers (initial BW=750 ± 52 lb.) evaluated the performance, carcass characteristic and fatty acid profiles from finishing steers fed four inclusions (0, 10, 20, 30 % DM basis) of Green Grass. Th ere were no differences in weights, gain or carcass traits. Dry matter intake tended to linearly increase as Green Grass inclusion increased in the diet. Steers fed Green Grass had greater F:G, and steers fed 30 % Green Grass had a lower marbling score. A linear increase in alpha linolenic acid, poly- unsaturated fatty acids, transunsaturated unsaturated fatty acids, and omega- 3 …