Veterinary Preventive Medicine, Epidemiology, and Public Health Commons^™

Migratory Flyways May Affect Population Structure In Double‐Crested Cormorants, Steven J.A. Kimble, Brian S. Dorr, Katie C. Hanson-Dorr, Olin E. Rhodes Jr., Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Double‐crested cormorants (Phalacrocorax auritus) recovered from a demographic bottleneck so well that they are now considered a nuisance species at breeding and wintering grounds across the United States and Canada. Management of this species could be improved by refining genetic population boundaries and assigning individuals to their natal population. Further, recent radio‐telemetry data suggest the existence of Interior and Atlantic migratory flyways, which could reduce gene flow and result in substantial genetic isolation. In this study, we used 1,784 individuals collected across the eastern United States, a large panel of microsatellite markers developed for this species, and individuals banded as …

Optimal Bait Density For Delivery Of Acute Toxicants To Vertebrate Pests, Kim M. Pepin, Nathan P. Snow, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Oral baiting is a fundamental method for delivering toxicants to pest species. Planning baiting strategies is challenging because bait-consumption rates depend on dynamic processes including space use and demographics of the target species. To determine cost-effective strategies for optimizing baiting, we developed a spatially explicit model of population dynamics using field-based measures of wild-pig (Sus scrofa) space use, bait consumption, and mortality probabilities. The most cost-effective baiting strategy depended strongly on the population reduction objective and initial density. A wide range of baiting strategies were cost-effective when the objective was 80% population reduction. In contrast, only a narrow range of …

Brodifacoum Residues In Fish Three Years After An Island-Wide Rat Eradication Attempt In The Tropical Pacific, Shane R. Siers, Aaron B. Shiels, Steven F. Volker, Kristen Rex, William C. Pitt

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive rats are known to threaten natural resources and human health and safety. Island-wide rat eradication attempts have been increasing in number and scale during the past several decades, as has the frequency of eradication success. The most common method to remove all rats from an island is to broadcast anticoagulant rodenticide bait into every rat’s home range on the island. Broadcast of toxicants can put humans and other nontarget species in marine and terrestrial environments at risk of exposure. The persistence of anticoagulant residues is somewhat unknown, particularly in marine environments. Three years after ~ 18,000 kg of 25 …

Local Adaptation Constrains Drought Tolerance In A Tropical Foundation Tree, Kasey E. Barton, Casey Jones, Kyle F. Edwards, Aaron B. Shiels, Tiffany Knight

United States Department of Agriculture Wildlife Services: Staff Publications

1. Plant species with broad climatic ranges might be more vulnerable to climate change than previously appreciated due to intraspecific variation in climatic stress tolerance. In tropical forests, drought is increasingly frequent and severe, causing widespread declines and altering community dynamics. Yet, little is known about whether foundation tropical trees vary in drought tolerance throughout their distributions, and how intraspecific variation in drought tolerance might contribute to their vulnerability to climate changE.
2. We tested for local adaptation in seedling emergence and establishment with a full-factorial reciprocal transplant experiment including 27 populations and 109,350 seeds along a 3,500 mm precipitation gradient for …

Genetic And Evolutionary Considerations Of The Chronic Wasting Disease – Human Species Barrier, Robert M. Zink

School of Natural Resources: Faculty Publications

Transmissible spongiform encephalopathies can jump species barriers. In relatively few cases is the possible route of transmission thought to be known, mostly involving humans, cattle and sheep. It is thought that sheep might be the cause of Bovine Spongiform Encephalopathy (BSE) and Chronic Wasting Disease (CWD) in cervids, and that humans might have gotten prion disease (e.g., vCJD) from eating meat from BSE+ cows. A looming societal question is whether humans will acquire a prion disease from ingesting prions from CWD+ deer. On an evolutionary tree of the PRNP gene in mammals, deer, sheep and cow are relatively closely related, …

Gulls As Sources Of Environmental Contamination By Colistin-Resistant Bacteria, Alan B. Franklin, Andrew M. Ramey, Kevin T. Bentler, Nicole L. Barrett, Loredana M. Mccurdy, Christina A. Ahlstrom, Jonas Bonnedahl, Susan A. Shriner, Jeffrey C. Chandler

United States Department of Agriculture Wildlife Services: Staff Publications

In 2015, the mcr-1 gene was discovered in Escherichia coli in domestic swine in China that conferred resistance to colistin, an antibiotic of last resort used in treating multi-drug resistant bacterial infections in humans. Since then, mcr-1 was found in other human and animal populations, including wild gulls. Because gulls could disseminate the mcr-1 gene, we conducted an experiment to assess whether gulls are readily colonized with mcr-1 positive E. coli, their shedding patterns, transmission among conspecifics, and environmental deposition. Shedding of mcr-1 E. coli by small gull flocks followed a lognormal curve and gulls shed one strain >101 …

Piscivorous Bird Use Of Aquaculture And Natural Water Bodies In Mississippi, Paul C. Burr, Jimmy I. Avery, Garrett M. Street, Bronson K. Strickland, Brian S. Dorr

United States Department of Agriculture Wildlife Services: Staff Publications

Double crested cormorants (Phalacrocorax auritus) and great egrets (Ardea alba) have an extensive history of human wildlife conflict with the aquaculture industry of western Mississippi, USA, due to

their depredation of cultured catfish (Ictalurus spp.). Although aquaculture is abundant, western Mississippi also contains naturally occurring water bodies that offer alternative forage opportunities to these species. How cormorants or egrets distribute themselves among these 2 foraging options is unknown, but it has been generally assumed each species uses aquaculture disproportionately more because of the high density of available prey. To test this assumption, we surveyed these …

Control Or Eradication: Problems In The Management Of Invasive Birds, Michael L. Avery, Chris J. Feare

United States Department of Agriculture Wildlife Services: Staff Publications

Humans have captured, transported and intentionally released wild birds for centuries (Blackburn et al., 2009). Motivations for such purposeful introductions include food (West and Zhou, 2007), religion (Agoramoorthy and Hsu, 2007), sport (McDowall, 1994), biocontrol (Bennett and Hughes, 1959; Kurdila, 1995) and aesthetics (Ryan, 1906; Thomson, 1922). Many purposeful bird introductions were the work of acclimatization societies, particularly in North America, New Zealand and Australia. These societies were formed in the 19th century by European settlers to transport bird species from their homelands in efforts to establish them in the newly settled regions (Thomson, 1922; Dunlap, 1997). As a result …

New Approach To Health And The Environment To Avoid Future Pandemics, Serge Morand

Animal Sentience

This commentary expands Wiebers & Feigin’s target article by pinpointing how declining wildlife, expanding livestock and globalisation contribute to the increase in epidemics of zoonotic diseases, the COVID-19 crisis and future health crises. Epidemics and the emergence of zoonoses are manifestations of dysfunctional links with animals, both wild and domestic, requiring a new approach to health and the environment.

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 …

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 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. …