Life Sciences Commons^™

Effect Of Supplementation Prior To Artificial Insemination And During Gestation In Beef Females, Landon Tadich

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

Objectives of Experiment 1 was to evaluate the impact of increased energy prior to AI on BW, ADG, and reproductive efficiency in heifers developed on range or in a dry lot. During the winter development period (131 ± 3.5 d/yr) heifers (n= 100/yr) were assigned to either upland range (RANGE) or fed a dry lot diet in two pens that either remained constant (DLLO) or increased in energy prior to AI (DLHI). Heifers developed on RANGE grazed upland winter range until 38 d prior to AI where they then received the DLLO diet. Pre-breeding BW was greater (P £ …

Effects Of Administration Of A Growth Promoting Implant During The Suckling Phase Or At Weaning On Growth, Reproduction, And Ovarian Development In Replacement Heifers Grazing Native Range, Shelby L. Rosasco, Emily A. Melchior-Tiffany, Cierrah J. Kassetas, Shad H. Cox, Richard L. Dunlap, Jennifer A. Hernandez Gifford, Eric J. Scholljegerdes, Robert A. Cushman, Adam F. Summers

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Management strategies utilized during pre-breeding development of replacement heifers can impact fertility and the ovarian reserve. Angus- Hereford crossbred heifers (n = 233) were utilized over a 3-yr period to determine the effects of administration of a growth promoting implant at either branding or weaning on growth, reproduction, and ovarian development. Heifer calves were randomly assigned to one of three treatments: 1) nonimplanted controls (CON; n = 79), 2) implanted at approximately 2 mo of age (average calf age = 58 d) with Synovex-C (BIMP, n = 82), or 3) implanted at approximately 7 mo of age (average calf …

Drivers Of Annual Fledging In The Mississippi Sandhill Crane Population 1991-2018, Henry W. Woolley, Scott G. Hereford, Jerome J. Howard,

Proceedings of the North American Crane Workshop

We studied trends in nesting, number of chicks fledged annually, and their environmental and biotic drivers in the wild population of Mississippi sandhill cranes (Grus canadensis pulla) on Mississippi Sandhill Crane National Wildlife Refuge during 1991-2018. Population size, number of nests, and number of chicks fledged annually increased slowly but significantly over the course of the study. Increases in population size were related to both number of wild-reared chicks fledged annually and number of captive-reared chicks released each year, but wild-reared chicks had significantly higher survivorship than captive-reared chicks. Hurricanes transiently raised mortality rates but only Hurricane Katrina …

Twenty-Year Status Of The Eastern Migratory Whooping Crane Reintroduction, Hillary L. Thompson, Nicole M. Gordon, Darby P. Bolt, Jadine R. Lee, Eva K. Szyszkoski

Proceedings of the North American Crane Workshop

Since the 10-year status update in 2011, the first parent-reared whooping cranes (Grus americana) were released in the Eastern Migratory Population, the ultralight program (UL) ended, and cranes were released at new sites in eastern Wisconsin. During 2011-2020, 117 captive-reared whooping cranes were released; 75 costume-reared (35 in UL and 40 in the Direct Autumn Release program) and 42 parent-reared. There were no significant differences in 1- or 3-year survival rates based on rearing technique or release site. The population size remained at about 100 cranes during 2010-2018 but then decreased during 2018-2020 due to a reduced number …

Vigilance Of Nesting Whooping Cranes In Juneau County, Wisconsin, Nicole M. Gordon, Darby P. Bolt, Hillary L. Thompson

Proceedings of the North American Crane Workshop

Vigilance plays an important role in the detection of possible threats and reducing the risk of predation, including during the incubation period. We examined the visual vigilance of incubating whooping cranes (Grus americana) in Juneau County, Wisconsin, during the 2019 nesting season. We deployed 9 trail cameras and tagged crane presence and behavior in 32,801 photos which were used in our analysis. We assessed individual nest and environmental variables and their effects on vigilant behavior of incubating cranes using linear mixed-models. Vigilant behavior was defined by a posture in which the crane’s head was up, neck was erect, …

Relationship Of Molecular Breeding Value For Beef Tenderness With Heifer Traits Through Weaning Of Their First Calf, Robert A. Cushman, Gary L. Bennett, Richard G. Tait, Anthony K. Mcneel, Eduardo Casas, Timothy P.L. Smith, Harvey C. Freetly

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Polymorphisms in μ-calpain (CAPN1) that beneficially associate with beef tenderness are reported to antagonistically associate with calving day in beef heifers and post-partum interval to estrus in beef cows. We, therefore, hypothesized that a molecular breeding value for slice shear force, calculated based on CAPN1 and calpastatin (CAST) genotypes, would demonstrate an antagonistic relationship between genomically predicted slice shear force and ordinal calving date in replacement beef heifers. A secondary objective of this study was to evaluate the association of a polymorphism in diacylglycerol O-acyltransferase (DGAT1) with reproductive traits in beef heifers. One hundred eighty-seven MARC III heifers (¼ Angus, …

Using Genomics To Measure Phenomics: Repeatability Of Bull Prolificacy In Multiple-Bull Pastures, Gary L. Bennett, John W. Keele, Larry A. Kuehn, Warren M. Snelling, Robert A. Cushman, Tara G. Mcdaneld, Aaron M. Dickey, Darrell Light

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Phenotypes are necessary for genomic evaluations and management. Sometimes genomics can be used to measure phenotypes when other methods are difficult or expensive. Prolificacy of bulls used in multiple-bull pastures for commercial beef production is an example. A retrospective study of 79 bulls aged 2 and older used 141 times in 4–5 pastures across 4 years was used to estimate repeatability from variance components. Traits available before each season’s use were tested for predictive ability. Sires were matched to calves using individual genotypes and evaluating exclusions. A lower-cost method of measuring prolificacy was simulated for five pastures using the bulls’ …

Changes In Whole Blood Parameters In Beef Heifers May Contribute To Delayed Pubertal Attainment, Jessica A. Keane

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

Pubertal development in beef heifers is a transient period that has many contributing factors. Previously in our lab, progesterone (P4) concentrations collected from heifers at weaning (Oct) to breeding (May) were used to identify four distinct pubertal groups: Typical, Early, Start-Stop, and Non-Cycling. There is limited research on heifers and the impacts of whole blood cell populations, particularly WBCs, during pubertal development; however, girls with differing puberty onset displayed altered concentrations of hematocrit, white blood cells (WBC), and hemoglobin concentrations. Thus, our hypothesis was that heifer pubertal groups with delayed or precocious puberty may have increased white blood cells or …

Observations On The Distribution And Status Of Selected Nebraska Mammals, Zachary P. Roehrs, Russell A. Benedict, Thomas E. Labedz, Hugh H. Genoways

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Information on the distribution and current status of 25 species or subspecies of mammals occurring in Nebraska are presented. The species covered include one shrew, an armadillo, eight bats, 10 rodents (including two subspecies of one species), three carnivores, and one artiodactyl. Distributional information reported includes the first state record for one species (Sorex nanus) and new county records for 18 species. In Nebraska, we know that mammals are shifting their geographic ranges with some extending populations into the state, whereas others are expanding their geographic ranges within the state. The current status of six additional mammalian taxa …

Comparison Of Performance Of F1 Romanov Crossbred Ewes With Wool And Hair Breeds During Spring Lambing Under Intensive And Extensive Production Systems, Brad A. Freking, Thomas W. Murphy

Roman L. Hruska U.S. Meat Animal Research Center: Reports

The objective was to evaluate wool (Dorset and Rambouillet) and hair (Dorper, Katahdin, and White Dorper) breeds for their ability to complement Romanov germplasm in two distinct production systems by estimating direct sire and grandsire effects on lamb growth, survival, and ewe productivity traits. Rams of the five breeds (n = 75) were mated to Romanov ewes (n = 459) over a 3-yr period to produce five types of crossbred lambs (n = 2,739). Sire breed (P > 0.06) did not impact body weight or survival traits of the first-generation crossbred (F1) lambs. The productivity of retained crossbred ewes (n = …

Der Kormoran Phalacrocorax Carbo In Der Mongolei, Michael Stubbe, Lucie Marie Baltz, Davaa Lchagvasuren, Lukas Kratzsch, Lara-Sophie Dey, Annegret Stubbe

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The Great Cormorant Phalacrocorax carbo is a wide spread breeding species in Mongolia with a progressive population trend. Observations of the Mongolian-German Biological Expeditions were analyzed and summarized with data from literature. About 1,500 young birds were ringed in 2016 and 2017. One important recovery was coming from the wintering area Mai Po Marshes Nature Reserve of Hong Kong. It is unclear if all Mongolian Cormorants are flying at the same route to their wintering region in South China. The main feeding fishes in Mongolia belong to endemic species of the genus Oreoleuciscus (Cyprinidae). Measurements of 113 eggs from Tolbo- …

Mist-Netting Of Forest-Dwelling Bats In The Lazovsky State Nature Reserve, Russian Far East, Kerstin Birlenbach

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Many bat species depend on a high value of healthy and undisturbed forests with a high ratio of roost sites in old tree stands. This investigation focused on the diversity, distribution and reproduction status of bats within the area of Lazovsky State Nature Reserve. The importance of an area for bats can be measured by the ratio of reproduction. The most important and sensitive time in a bats yearly circle is the time of hibernation in winter and the reproduction time of females. From the beginning of July to the end of August 2007, in total 139 bats of eight …

Review: Perspective On High-Performing Dairy Cows And Herds, J. H. Britt, R. A. Cushman, C. D. Dechow, H. Dobson, P. Humblot, M. F. Hutjens, G. A. Jones, F. M. Mitloehner, P. L. Ruegg, I. M. Sheldon, J. S. Stevenson

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Milk and dairy products provide highly sustainable concentrations of essential amino acids and other required nutrients for humans; however, amount of milk currently produced per dairy cow globally is inadequate to meet future needs. Higher performing dairy cows and herds produce more milk with less environmental impact per kg than lower performing cows and herds. In 2018, 15.4% of the world's dairy cows produced 45.4% of the world's dairy cow milk, reflecting the global contribution of high-performing cows and herds. In high-performing herds, genomic evaluations are utilized for multiple trait selection, welfare is monitored by remote sensing, rations are formulated …

Surgical Sterilization Impacts On Behavior Of Coyote Pairs, Tyler Leary, Jeffrey T. Schultz, Julie K. Young

USDA Wildlife Services: Staff Publications

Coyotes (Canis latrans) involved in depredation of livestock, an act frequently resulting in human-wildlife conflict, often do so out of necessity for provisioning pups. Surgical sterilization methods such as vasectomy that preserve gonadal hormones have been successful in reducing depredation by free-ranging coyotes while allowing individuals to maintain territoriality and mate fidelity. However, use of these methods remain costly and ineffective for wide-scale use. Given the alternative proposal of using chemical sterilization techniques, we investigated whether the use of hormone-altering sterilization methods impacted behavior of captive coyote pairs (i.e., male-female pair bonds). Our objective was to evaluate behavior …

Measuring Adrenal And Reproductive Hormones In Hair From Southern Beaufort Sea Polar Bears (Ursus Maritimus), Marilize Van Der Walt, Lorin A. Neuman-Lee, Patricia A. Terletzky, Todd C. Atwood, Eric M. Gese, Susannah S. French

USDA Wildlife Services: Staff Publications

Polar bears (Ursus maritimus) use sea ice to access marine mammal prey. In Alaska’s Southern Beaufort Sea, the declining availability of sea ice habitat in summer and fall has reduced opportunities for polar bears to routinely hunt on the ice for seals, their primary prey. This reduced access to prey may result in physiological stress with subsequent potential consequences to reproductive function (physiological changes that accompany reproduction), which can be measured via reproductive hormones. Hormone concentrations in hair can be used as a minimally invasive alternative to serum concentrations, which must come from animal captures. Hair samples also …

Reproductive Trade-Offs In The Colorado Checkered Whiptail Lizard (Aspidoscelis Neotesselatus): An Examination Of The Relationship Between Clutch And Follicle Size, Hannah E. Caracalas, S. S. French, S. B. Hudson, B. M. Kluever, A. C. Webb, D. Eifler, A. J. Lehmicke, Lise M. Aubry

USDA Wildlife Services: Staff Publications

Life history theory predicts that there should be an inverse relationship between offspring size and number, because individuals cannot simultaneously maximize both when resources are limited. Although extensively studied in avian species, the occurrence and determinants of reproductive tradeoffs in oviparous reptiles are far less understood, particularly in parthenogenetic species. We studied this trade-off in the Colorado Checkered Whiptail, Aspidoscelis neotesselatus, a female-only parthenogenetic lizard. Using data previously collected in 2018 and 2019, we tested for clutch and egg size trade-offs and determined whether this relationship could be influenced by female size and aspects of physiological condition. Physiological condition …

Competing Reproductive And Physiological Investments In An All‑Female Lizard, The Colorado Checkered Whiptail, Lise M. Aubry, Spencer B. Hudson, Bryan M. Kluever, Alison C. Webb, Susannah S. French

USDA Wildlife Services: Staff Publications

Organisms in the wild have to allocate limited resources towards competing functions such as reproduction, growth, and self-maintenance. These competing investments create significant changes in physiological activity, and we still know little about the relationship between physiological activity and reproductive investment in natura. We investigated trade-offs between physiological activity and reproductive investment in the parthenogenetic Colorado checkered whiptail, Aspidoscelis neotesselata, across three different sites at the US Army Fort Carson Military Installation near Colorado Springs, CO, through-out the reproductive season in 2018 and 2019. We measured clutch size and reproductive activity and quantified plasma corticosterone (CORT), reactive oxygen metabolites (ROMs), …

The Impact Of Heat Load On Cattle, Angela M. Lees, Veerasamy Sejian, Andrea L. Wallage, Cameron C. Steel, Terry L. Mader, Jarrod C. Lees, John B. Gaughan

Department of Animal Science: Faculty Publications

Heat stress and cold stress have a negative influence on cattle welfare and productivity. There have been some studies investigating the influence of cold stress on cattle, however the emphasis within this review is the influence of heat stress on cattle. The impact of hot weather on cattle is of increasing importance due to the changing global environment. Heat stress is a worldwide phenomenon that is associated with reduced animal productivity and welfare, particularly during the summer months. Animal responses to their thermal environment are extremely varied, however, it is clear that the thermal environment influences the health, productivity, and …

Bats Of Saint Lucia, Lesser Antilles, Scott C. Pedersen, Gary G. Kwiecinski, Hugh H. Genoways, Roxanne J. Larsen, Peter A. Larsen, Carleton J. Phillips, Robert J. Baker

University of Nebraska State Museum: Mammalogy Papers

Eight species of bat have been previously recorded from the island of Saint Lucia: Noctilio leporinus, Monophyllus plethodon, Artibeus jamaicensis, Brachyphylla cavernarum, Ardops nichollsi, Sturnira paulsoni, Molossus molossus, and Tadarida brasiliensis. Herein, we add a ninth species to the fauna—Pteronotus davyi. These nine species represent nine genera from four families: Noctilionidae, Mormoopidae, Phyllostomidae, and Molossidae. This fauna includes four trophic guilds: N. leporinus (piscivore/insectivore), M. plethodon (nectarivore/pollenivore), A. jamaicensis × schwartzi, B. cavernarum, A. nichollsi, and S. paulsoni (frugivores), and P. davyi, M. molossus, and …

Bats Of St. Vincent, Lesser Antilles, Gary G. Kwiecinski, Scott C. Pedersen, Hugh H. Genoways, Peter A. Larsen, Roxanne J. Larsen, Justin D. Hoffman, Fitzroy Springer, Carleton J. Phillips, Robert J. Baker

University of Nebraska State Museum: Mammalogy Papers

The chiropteran fauna of the island of Saint Vincent, represented by 12 species, is among the most complex in the Lesser Antilles, being represented by four families including Noctilionidae (1 species), Mormoopidae (1), Phyllostomidae (8), and Molossidae (2). This fauna includes four trophic guilds as represented by Noctilio leporinus (piscivore/insectivore); Glossophaga longirostris and Monophyllus plethodon (nectarivore/pollenivore); Artibeus lituratus, A. schwartzi, Brachyphylla cavernarum, Ardops nichollsi, and Sturnira paulsoni (frugivore); and Pteronotus fuscus, Micronycteris buriri, Molossus molossus, and Tadarida brasiliensis (insectivore). One species—Micronycteris buriri—and two subspecies—Sturnira paulsoni paulsoni and Ardops nichollsi vincentensis …

Predators Modify The Temperature Dependence Of Life-History Trade-Offs, Thomas M. Luhring, Janna M. Vavra, Clayton E. Cressler, John Delong

School of Biological Sciences: Faculty Publications

Although life histories are shaped by temperature and predation, their joint influence on the interdependence of life-history traits is poorly understood. Shifts in one life-history trait often necessitate shifts in another—structured in some cases by trade-offs— leading to differing life-history strategies among environments. The offspring size–number trade-off connects three traits whereby a constant reproductive allocation (R) constrains how the number (O) and size (S) of offspring change. Increasing temperature and size-independent predation decrease size at and time to reproduction which can lower R through reduced time for resource accrual or size-constrained fecundity. We investigated how O, S, and R in …

Triennial Reproduction Symposium: Looking Back And Moving Forward—How Reproductive Physiology Has Evolved, Deb L. Hamernik, Andrea S. Cupp, John S. Davis

Department of Animal Science: Faculty Publications

In honor of the 50th anniversary of the Society for the Study of Reproduction (SSR), a Triennial Reproduction Symposium was cosponsored by SSR and the American Society of Animal Science (ASAS). The Society for the Study of Reproduction was formed in 1967 when a group of reproductive biologists that were members of ASAS met with physician scientists and decided to organize a new scientific society. The goal of SSR was to promote the study of reproduction by fostering interdisciplinary communication among scientists, holding conferences, and publishing meritorious studies. Today after its 50th anniversary, the mission for SSR is to harness …

Reproductive Characteristics Of Landlocked Fall Chinook Salmon From Lake Oahe, South Dakota, Kelsen L. Young, Michael E. Barnes, Jeremy L. Kientz

The Prairie Naturalist

Lake Oahe, South Dakota, USA, landlocked fall Chinook salmon (Oncorhynchus tshawytscha) reproductive characteristics were examined over a 27 year period, from 1988 to 2015. Mean total lengths of spawning females ranged from 665 mm (1995) to 812 mm (2015) with considerable year-to-year variation. Post-spawn female weights varied, ranging from 2.02 kg (2000) to 5.55 kg (2015), with an overall mean of 3.04 kg. Fecundity peaked at 4,555 eggs per female in 2003, which was just 3 years after a low of 2,011 eggs per female in 2000. Relative fecundity based on female weight was greatest at 1,211 eggs/kg …

Ten-Year Status Of The Eastern Migratory Whooping Crane Reintroduction, Richard P. Urbanek, Sara E. Zimorski, Eva K. Szyskoski, Marianne M. Wellington

Proceedings of the North American Crane Workshop

From 2001 to 2010, 132 costume-reared juvenile whooping cranes (Grus americana) were led by ultralight aircraft from Necedah National Wildlife Refuge (NWR) in central Wisconsin to the Gulf Coast of Florida on their first autumn migration (ultralight-led or UL), and 46 juveniles were released directly on Necedah NWR during autumn of the hatch year (direct autumn release or DAR). Return rate in spring was 90.5% for UL and 69.2% for DAR, the lower value of the latter attributable to 1 cohort with migration problems. Overall population survival 1 year and from 1 to 3 years post-release was 81% and 84%, …

Effects Of Pubertal Status And Number Of Estrous Cycles Prior To Breeding In Beef Heifers, Average Daily Gain On Reproductive Performance And Comparison Of Two Fixed Time Ai Estrus Synchronization Protocols, Rebecca Vraspir

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

Reproductive success is the most important factor in beef cattle production and is affected by timing of pubertal onset in heifers, and reproductive biotechnologies utilized. Three studies were conducted to evaluate the effects of pubertal status, ADG, and 2 fixed time AI protocols on reproductive success in beef heifers.

In the first study, heifers that were pubertal prior to breeding had a greater AI and overall pregnancy rate; produced more calves born within the first 21 d of the calving season; and weaned older, heavier calves than non-pubertal heifers. Additionally, heifers that had ≥2 estrous cycles, prior to the first …

Fear Effects On Pheasant Reproductive Ecology And A Curriculum To Teach Wildlife Habitat Selection, Jessica Laskowski

School of Natural Resources: Dissertations, Theses, and Student Research

Predation risk is an important source of selection that shapes prey density, distribution and abundance. The immediate impacts of predator consumption on prey populations are widespread and well-studied, and a growing body of research demonstrates immediate impacts of predator-induced fear (independent of prey mortality) on prey behavior, physiology and life-history expression. However, predation risk is often seasonally variable and while it is clear that consumption effects often carry over to influence prey population demography for years after predators have disappeared, the temporal carry-over effects of fear on prey populations remain largely unexplored. We assessed effects of fall hunting activity by …

Shovelnose Sturgeon Reproductive Ecology In The Lower Platte River, Nebraska, Mathew L. Rugg

School of Natural Resources: Dissertations, Theses, and Student Research

Biodiversity and abundance of freshwater organisms are experiencing drastic declines. Anthropogenic disturbances have altered the natural flow regimes of large rivers, and have led to declines in species that rely on elements of natural flow. Similarly, shovelnose sturgeon distribution has diminished in the last 100 years due to habitat alteration, overharvest, and water contamination. To fully understand the status and viability of a fish population, basic knowledge of a fish’s reproductive strategy is needed. Aspects of reproduction that should be understood to manage for sustainability include maturation, fecundity, and spawning dynamics. There is currently little published information on age/size of …

Genome-Wide Prediction Of Age At Puberty And Reproductive Longevity In Sows, Julie Kathleen Tart, Rodger K. Johnson, Justin W. Bundy, N. N. Ferdinand, A. M. Mcknite, Jennifer R. Wood, Phillip S. Miller, M. F. Rothschild, Matthew L. Spangler, Dorian J. Garrick, Stephen D. Kachman, Daniel C. Ciobanu

Department of Animal Science: Faculty Publications

Traditional selection for sow reproductive longevity is ineffective due to low heritability and late expression of the trait. Incorporation of DNA markers into selection programs is potentially a more practical approach for improving sow lifetime productivity. Using a resource population of crossbred gilts, we explored pleiotropic sources of variation that influence age at puberty and reproductive longevity. Of the traits recorded before breeding, only age at puberty significantly affected the probability that females would produce a first parity litter. The genetic variance explained by 1-Mb windows of the sow genome, compared across traits, uncovered regions that influence both age at …

Genome-Wide Association Analyses Of Sow Reproduction And Lifetime Productivity, Daniel Ciobanu

Department of Animal Science: Faculty Publications

Concurrent with increased prolificacy, high sow death losses and replacement rates are serious economic and welfare issues facing producers. Reproductive failure is the most frequent reason for culling sows. Lifetime productivity is characterized by moderate heritability and high phenotypic variance and, as a result, substantial genetic variation is expected to exist in most populations. Traditional selection for sow reproductive longevity results is ineffective due to low heritability and late expression of the trait. The primary goal of this research project was to identify DNA markers associated with reproductive and sow lifetime productivity that can be used in nucleus herds to …

Reproduction And Population Characteristics Of White-Tailed Jackrabbits In South Dakota, Charles Dieter, Dustin Schaible

Great Plains Research: A Journal of Natural and Social Sciences

We evaluated the reproductive biology of314 white-tailed jackrabbits (Lepus townsendii) in 44 counties throughout South Dakota from June 2004 to September 2005. We classified jackrabbits as juveniles or adults based on the closure of the proximal epiphysis of the humerus using X-ray analysis. We determined annual reproductive activity through fluctuations in measured weights of reproductive organs for both sexes. The 2005 breeding season started in late February and proceeded until mid-July, approximately 142 days, allowing for females to potentially produce 3.3 litters. We found four distinct breeding periods by the overlap of estimated conception and parturition dates. Mean …