Animal Sciences Commons^™

Comparison Of Wet And Dry Distillers Grains Plus Solubles To Corn As An Energy Source In Forage-Based Diets, Nerissa Ann Ahern, Brandon L. Wingeyer, Terry J. Klopfenstein, James C. Macdonald, Galen E. Erickson, Andrea K. Watson

Department of Animal Science: Faculty Publications

Four experiments compared wet or dry distillers grains plus solubles (WDGS or DDGS) to corn as energy sources in forage-based diets. In Exp. 1, 66 individually fed steers (268 kg of initial BW) were fed a 60:40 blend of sorghum silage and alfalfa hay and supplemented at 0, 0.33, 0.67, or 1.0% of BW with either WDGS or DDGS. In Exp. 2, 160 steers (286 kg of initial BW) were fed 25% WDGS or 33.6% dry rolled corn (DRC) in 35% sorghum silage and grass hay diets (DM basis). In Exp. 3, 60 individually fed steers (231 kg of initial …

Effects Of Small Intestinal Starch Digestion And Dietary Lipid On Efficiency Of Nitrogen Use In Cattle, Ethan J. Blom

Electronic Theses and Dissertations

The objective of this research was to determine the effects of increases in energy available for gain from increased small intestinal starch digestion (SISD) and dietary lipid source and amount on the efficiency of N use in cattle. Five ruminally, duodenally, and ileally cannulated steers were placed in a 5 × 5 Latin square. Each received duodenal infusion of 1.5 ± 0.08 kg/d raw cornstarch and either 0, 30.9 ± 0.59, 62.4 ± 1.16, or 120.4 ± 3.39 g/d Glu, or 387.9 ± 17.47 g/d casein. Casein increased (P = 0.05) SISD. Similarly, greater duodenal Glu linearly (P = 0.02) …

Cla And Epa Inhibit Lps-Induced Prostaglandin Release From Bovine Endometrial Cells Through An Nf-?B-Dependent Signaling Mechanism, Lokenga Badinga, Mehmet Şükrü Gülay, Alan Ealy

Turkish Journal of Veterinary & Animal Sciences

Although their action in antagonizing arachidonic acid metabolism is a key antiinflammatory effect of conjugated linoleic acid (CLA) and omega-3 polyunsaturated fatty acids (n-3 PUFA), these molecules have other antiinflammatory effects that might occur upstream of altered eicosanoid production. We examined the effects of two CLA isomers (c9,t11 and t10,c12 isomers), n-3 PUFA (EPA and DHA), and ΚNF-ΚB inhibitor (ammonium pyrrolidine dithiocarbamate (PDTC)) on lipopolysaccharide (LPS)-induced secretion of prostaglandins (PGE2 and PGF2a) by bovine endometrial (BEND) cells. LPS increased PGE2 and PGF2a concentrations in BEND cell-conditioned media in a concentration- and time-dependent manner. The c9,t11 CLA isomer and EPA decreased …

Mast Cell Typing In Aortic Onchocerciasis And The Immunohistochemicaldemonstration Of Wolbachia Bacteria, Rahşan Yilmaz, Melek Koçak, Zafer Özyildiz, İsmai̇l Şah Harem

Turkish Journal of Veterinary & Animal Sciences

In this study, the presence of endosymbiotic Wolbachia bacteria was determined by immunohistochemical methods in 8 out of 43 paraffin-embedded bovine aortic tissues that were macroscopically and microscopically diagnosed with aortic onchocerciasis in the archive of the Harran University Faculty of Veterinary Medicine's Department of Pathology. By means of the enzyme histochemical and immunohistochemical staining methods, it was ascertained that the tryptase-containing subtype of mast cells (MCT) was involved in the inflammatory response in the bovine aortae with onchocerciasis. The aim of this study was to elucidate the pathogenesis of aortic onchocerciasis lesions caused by Onchocerca armillata in Turkey and …

Mycoplasma Infections In Dairy Cattle Farms In Turkey, Zafer Sayin, Asli Sakmanoğlu, Uçkun Sai̇t Uçan, Ali̇ Uslu, Hasan Hüseyi̇n Hadi̇mli̇, Zeki̇ Aras, Özgür Özdemi̇r, Osman Ergani̇ş

Turkish Journal of Veterinary & Animal Sciences

Mycoplasmas cause the most severe and economically costly diseases of cattle throughout the world. In this study, Mycoplasma species were isolated from calves and cows with suspected mycoplasmosis in Holstein dairy cattle farms within 7 geographical regions of Turkey between May 2010 and December 2015. Mycoplasma infections were positive in 17 (80.9%) of 21 dairy cattle farms and the overall percentage was calculated as 32.1%. The highest isolation rate occurred in the Southeastern Anatolia Region (42.8%), and the lowest was observed in the Mediterranean Region (19.6%). In total, 172 Mycoplasma spp. were isolated from samples. Using PCR analysis, 149 (87.6%) …

Molecular Identification Of Bovine Papillomaviruses In Dairy And Beef Cattle: First Description Of Xi- And Epsilonpapillomavirus In Turkey, Veysel Soydal Ataseven, Özgür Kanat, Yaşar Ergün

Turkish Journal of Veterinary & Animal Sciences

In the current study, 23 papilloma/tumor-like samples obtained from cattle having clinical lesions and 9 blood samples collected from healthy-appearing cattle in Turkey were examined for bovine papillomavirus (BPV) DNA using the degenerate primers FAP59/64, and the different types of BPV were distinguished by type-specific primer sets. Furthermore, histopathological studies of papillomavirus were performed. A total of 7 BPV types (BPVs 1, 2, 3, 4, 6, 8, 9), including genera Deltapapillomavirus, Xipapillomavirus, and Epsilonpapillomavirus, were identified. In all samples, BPV-1 was the most common genotype (90.6%). Overall, coinfections were determined in 26 of the examined samples (81.3%), and coinfection with …

The Evaluation Of Eprinomectin (Longrange®) On Long-Term Parasitic Infection In Nursing Calves During Summer Grazing®, Lyndsea D. Seibert

LSU Master's Theses

One of the most significant threats to the well-being and performance of grazing livestock are gastrointestinal nematode (GIN) parasitic infections. Allowing a large GIN burden to manifest can cause a significant cost in terms of productivity in grazing cattle. Beef producers commonly rely greatly on the efficacy of broad-spectrum anthelmintics, to not only kill resident worms but to also prevent the establishment of ingested infective stage larvae (L3) for a period following treatment. Eprinomectin (LONGRANGE®, E-LR) is the first extended-release injectable cattle dewormer that claims to provide cattle producers season-long persistent parasite control for 100 to 150 d in a …

Comparison Of Hematological Parameters Of Brucella-Seronegative Naturallyinfected Cattle With Bvdv, Bhv-1, And Bhv-4, Muhammet Eren Aslan, Ahmet Kürşat Azkur, Emel Biyikli, Serkal Gazyağci, İbrahi̇m Sözdutmaz

Turkish Journal of Veterinary & Animal Sciences

Abortion, neonatal deaths, and infertility cause important production losses in the livestock industry. Many viral infections are responsible for changes in hematological values of animals. This study aimed to find whether there is any difference in blood parameters of cattle that are naturally infected with BVDV, BHV-1, and BHV-4 and Brucella-seronegative. For this purpose, 401 whole-blood samples collected from cattle were analyzed by ELISA and PCR/RT-PCR to detect specific antibodies and antigens for BVDV, BHV-1, and BHV-4. Hematological analysis and results were compared between naturally infected BVDV, BHV-1, and BHV-4 groups and a control group. Results showed a statistically significant …

The Effect Of Dgat1 Polymorphism On Milk Production Traits In Dairycows Depending On Environmental Temperature, Jolanta Komisarek, Mateusz Kolenda

Turkish Journal of Veterinary & Animal Sciences

It has long been known that a hot environment negatively influences milk production in cattle. Although molecular mechanisms underlying this phenomenon to a great extent remain to be recognized, they include alterations in lipid metabolism. DGAT1 plays a key role in the synthesis of triacylglycerols and polymorphism of this gene has been proven to have a pronounced influence on milk production. The aim of this study was to establish if the effect of DGAT1:p.K232A on milk-related traits is dependent on environmental thermal conditions. The analysis, performed on 468 cows of the Polish Holstein-Friesian breed, showed that allele DGAT1:K232 significantly increased …

Summer-Long Grazing Of High Vs. Low Endophyte (Neotyphodium Coenophialum)-Infected Tall Fescue By Growing Beef Steers Results In Distinct Temporal Blood Analyte Response Patterns, With Poor Correlation To Serum Prolactin Levels, Joshua J. Jackson, Merlin D. Lindemann, James A. Boling, James C. Matthews

Animal and Food Sciences Faculty Publications

Previously, we reported the effects of fescue toxicosis on developing Angus-cross steer growth, carcass, hepatic mRNA, and protein expression profiles of selected serum proteins, and blood clinical and chemical profiles, after summer-long grazing (85 days) of high endophyte (HE)- vs. low endophyte (LE)-infected fescue pastures. We now report the temporal development of acute, intermediate, and chronic responses of biochemical and clinical blood analytes determined at specified time intervals (period 1, day 0–36; period 2, day 37–58; and period 3, day 59–85). Throughout the trial, the alkaloid concentrations of the HE forage was consistently 19–25 times greater (P ≤ 0.002) …

Investigations Into The Cross-Infectivity Of Nematode Parasites Of Cattle And Sheep, Eva Marie Wray

Graduate Theses and Dissertations

The existence of anthelmintic resistance is not singular in parasite species, host species or geographic region. It has become a problem of worldly stature, especially when considering sheep nematodes. Recommendations have been modified from chemical-based control to multipart, managerial intervention. Compared with nematodes of cattle, the worldwide resistance of sheep nematodes to anthelmintic remedies is much more pronounced and urgent. As the resistance to essentially all anthelmintic classes approaches a cautionary level, the implementation of non-chemical controls has grown increasingly essential. Six-6 to 8 month old Holstein steer calves, six-5 month old Katahdin ram lambs and eight-5 month old Suffolk …

Dietary Strategies For Mitigation Of Methane Production By Growing And Finishing Cattle, Anna C. Pesta

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

Interest in reducing methane (CH₄) emissions by cattle has increased recently. Loss of feed energy as CH₄ represents both an environmental concern and an energetic loss to the animal. Manipulation of dietary composition has proven to be an effective mitigation strategy. Experiments were conducted to evaluate the effect of several dietary characteristics on CH₄ production in growing and finishing cattle, and to develop a novel, non-invasive method for quantifying emissions from animals in a production setting. Short-term gaseous emissions of CH₄ and carbon dioxide (CO₂) were measured and the CH₄:CO_{2 …}

The Influence Of The Bovine Fecal Microbiota On The Shedding Of Shiga Toxin-Producing Escherichia Coli (Stec) By Beef Cattle, Nirosh D. Aluthge

Department of Food Science and Technology: Dissertations, Theses, and Student Research

During the past three decades, Shiga toxin-producing E.coli (STEC) have emerged as an important food safety concern. Although initially E. coli O157 was the main focus, recent outbreaks and resulting investigations have shown that certain non-O157 STEC are as much a threat to food safety as their O157 counterparts. To the beef industry, STEC have been of particular concern due to the frequent association of beef and beef products as vehicles of STEC infection. As a result, along with E. coli O157, six non-O157 STEC serogroups (known as the ‘big six’) are now regulated as adulterants in certain raw beef …

Estimation Of Breed-Specific Heterosis Effects For Birth, Weaning, And Yearling Weight In Cattle, Lauren N. Schiermiester, R. M. Thallman, Larry Kuehn, Stephen D. Kachman, Matthew L. Spangler

Department of Animal Science: Faculty Publications

Heterosis, assumed proportional to expected breed heterozygosity, was calculated for 6834 individuals with birth, weaning and yearling weight records from Cycle VII and advanced generations of the U.S. Meat Animal Research Center (USMARC) Germplasm Evaluation (GPE) project. Breeds represented in these data included: Angus, Hereford, Red Angus, Charolais, Gelbvieh, Simmental, Limousin and Composite MARC III. Heterosis was further estimated by proportions of British × British (B × B), British × Continental (B × C) and Continental × Continental (C × C) crosses and by breed-specific combinations. Model 1 fitted fixed covariates for heterosis within biological types while Model 2 fitted …

Case Study: Producer Concerns And Perceptions Regarding The Effect Of Methane On Cattle Production And The Environment: A Survey Of Nebraska Producers, B. M. Boyd, A. Jones, Lisa Franzen-Castle, K. Jenkins, Richard J. Rasby, Matt K. Luebbe, Richard R. Stowell, Samodha C. Fernando, Galen E. Erickson

Department of Animal Science: Faculty Publications

Enteric methane production from cattle and its effect on climate change has been a topic of debate. Multiple studies have explored methods to reduce cattle enteric methane production while simultaneously improving performance. However, most strategies developed have not been widely implemented by cattle producers. Knowledge of producer concerns and perceptions on methane production from cattle and its effect on the environment may be limited. Therefore, the objectives of this survey were to determine what Nebraska producers know about methane production by cattle and how it affects performance and to determine whether different age groups, regions of Nebraska, and production size …

Exogenous Administration Of Lipids To Steers Alters Aspects Of The Innate Immune Response To Endotoxin Challenge, Nicole C. Burdick Sanchez, Jeffery A. Carroll, Janet R. Donaldson, Joe O. Buntyn, Ty B. Schmidt

Department of Animal Science: Faculty Publications

This study examined the effects of increasing energy availability from both dextrose and lipid treatments on the proinflammatory response to LPS in Holstein steers. Steers were randomly assigned to one of three groups: saline at 0.5 ml/ kg body weight (Control) or 50% dextrose [0.5 ml/kg body weight (Dextrose) to mimic calm cattle’s response to LPS] administered immediately prior to LPS (0.5 mg/kg body weight at 0 h) or continuous lipid emulsion infusion from –1 to 6 h [Intralipid 20% (Baxter, Deerfield, IL USA); 0.5 ml/kg/hr (Lipid) to mimic temperamental cattle]. Concentrations of non-esterified fatty acids (NEFA) were greater in …

Cattle With Increased Severity Of Bovine Respiratory Disease Complex Exhibit Decreased Capacity To Protect Against Histone Cytotoxicity, J. A. Matera, B. K. Krehbiel, J. A. Hernandez Gifford, D. L. Step, C. R. Krehbiel, C. A. Gifford

Department of Animal Science: Faculty Publications

Bovine respiratory disease complex (BRDC) is the leading cause of morbidity and mortality in feedlot cattle. Significant inflammation and lesions are often observed in lungs of infected cattle. During acute inflammatory responses, histones contribute to mortality in rodents and humans and serum proteins can protect against histone-induced cytotoxicity. We hypothesized that cattle experiencing chronic or fatal cases of BRDC have reduced ability to protect against cytotoxic effects of histones. Serum samples were collected from 66 bull calves at the time of normal feedlot processing procedures. Animals were retrospectively assigned to groups consisting of calves never treated for BRDC (control [CONT]; …

Energy Status Of Steers Dictates Effectiveness Of Glycerol Inclusion In High-Roughage And High-Concentrate Feedlot Diets, Erin M. Rife

Electronic Theses and Dissertations

The objective of this research was to determine how to use glycerol as an effective source of energy in ruminant diets. Steer calves were used in a 56 d backgrounding study (n=128; Initial BW=340 ± 15 kg) and 105 d finishing study (n=120; Initial BW=420 ± 20 kg). Dietary treatments during backgrounding included 0, 8, 16, and 24% glycerol replacing corn silage in corn silage-based diets. Steers continued on within relative levels of dietary glycerol with finishing diets consisting of 0, 5, 10, and 15% glycerol replacing corn. Cumulative DMI, ADG, and G:F increased linearly (P

A Study Evaluating Genetic Trends And Molecular Predisposition To Improved Carcass Quality Of Brahman And Brahman Influenced Cattle, Amanda M. Royer

LSU Master's Theses

The first objective of the current study was to evaluate genetic trends from 10 years of the American Brahman Breeders Association Carcass Evaluation Program from 2004 to 2013. Changes of performance in growth, carcass composition, and carcass quality traits were evaluated. Overall means were calculated to report the total average for each trait along with an average rate of change per year. Growth traits evaluated included feedlot entrance weight (INWT), harvest weight (HRVWT), and average daily gain (ADG). Carcass composition and quality traits evaluated included hot carcass weight (HCW), rib eye area (REA), marbling score (MARB), dressing percent (DP), quality …

Single Nucleotide Polymorphism Identification And Characterization Of Gnrhr Gene In Bos Taurus And Bos Indicus Cattle, Ramesha Kerekoppa, Marappa Basavaraju, Akhila Rao, Gujjar Ramachandra Geetha, Kataktalware Mukund, Jeyakumar Sakthivel

Turkish Journal of Veterinary & Animal Sciences

The hypothalamic gonadotropin-releasing hormone receptor (GnRHR) plays an essential physiological role in reproductive function. In this investigation, we studied genetic variation in the entire coding region of GnRHR gene using PCR-SSCP technique in 250 Bos taurus (Holstein Friesian, Jersey) and Bos indicus (Malnad Gidda, Deoni) bulls. The genetic variants in GnRHR gene were determined by PCR-SSCP technique by using 5 sets of primers. SSCP analysis of fragment 1, comprising exon 1, and fragment 3, comprising exon 2, revealed 2 SSCP patterns in all breeds under study, while fragment 2 of exon 1 and fragment 4, comprising exon 3, revealed 3 …

Serological And Molecular Diagnosis Of Paratuberculosis In Dairy Cattle, Kadi̇r Semi̇h Gümüşsoy, Tuba İça, Seçi̇l Abay, Fuat Aydin, Harun Hizlisoy

Turkish Journal of Veterinary & Animal Sciences

In this study, the presence of paratuberculosis was investigated by serological and molecular methods in herds of dairy cattle. Blood, milk, and stool samples of 147 cows aged 2 years old or older with chronic diarrhea were collected. A California mastitis test (CMT) was performed on milk samples. Indirect paratuberculosis enzyme-linked immunosorbent assay (ELISA) test was used for serological investigation. Polymerase chain reaction (PCR) was utilized for molecular identification of Mycobacterium avium subsp. paratuberculosis (MAP) from milk and stool samples. Immunomagnetic separation (IMS) method was used for milk and fecal samples. Eighteen (12.24%), 44 (29.93%), 36 (24.49%), 28 (19.05%), and …

Estimating Allele Frequencies Of Some Hereditary Diseases In Holstein Cattlereared In Burdur Province, Turkey, Özgecan Korkmaz Ağaoğlu, Ali̇ Reha Ağaoğlu, Mustafa Saatci

Turkish Journal of Veterinary & Animal Sciences

The economics of dairy cattle breeding around the world has been significantly affected by the autosomal recessive hereditary diseases of bovine leukocyte adhesion deficiency (BLAD), factor XI deficiency (FXID), bovine citrullinemia (BC), and deficiency of uridine monophosphate synthase (DUMPS). The aim of this study was to determine BLAD, FXID, BC, and DUMPS alleles in Holstein cattle raised in Burdur Province in Turkey. This study involved taking blood samples randomly from 500 head of Holstein cattle at various dairy farms in different towns in Burdur Province. Polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) analysis was employed to identify cows …

Changes In Corn Residue Quality Throughout The Grazing Period And Effect Of Supplementation Of Calves Grazing Corn Residue, Amanda J. Burken

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

Corn residue is an abundant feed source in Nebraska that can be utilized as an alternative winter feed. Calves were backgrounded on corn residue in order to determine gain and estimate forage intake when supplemented with distillers grains (DGS). Calves grazing the non-irrigated field gained more (1.03 kg/calf daily) when compared to those grazing the irrigated field (0.90 kg/calf daily; P < 0.01). In year 1, a quadratic effect for intake of DGS was present (P < 0.01) while year 2 observed a linear effect for increasing level of DGS (P < 0.01). The nutritional quality of corn residue was evaluated over time in order to determine changes in blade/sheath, cob, husk/shank and stem. Minimal changes in DM of the forage components occurred was grain reached 15.5% moisture. Digestibility of the blade/sheath declined linearly over time (P < 0.01) while the husk remained constant (P = 0.40). Cob digestibility decreased quadratically (P < 0.01) throughout the sampling period with few changes once grain reached 15.5% moisture. Differences observed in the digestibility of the blade/sheath were attributed to the effects of weathering. A third set of trials was conducted to evaluate the effects of by-product supplementation of calves grazing irrigated corn residue and supplemented with DGS or continuous access to lick tubs. The DGS treatment gained more (0.62 kg/calf daily) than the lick tub treatment (0.38 kg/calf daily; P < 0.01). Calves offered DGS consumed more supplement as a percentage of BW (0.52%) when compared with calves offered lick tubs (0.36%; P < 0.01) on a DM basis. Calves supplemented with DGS had a higher supplement efficiency (46.3% to 42.9%, DM basis) although no differences were present between treatments (P = 0.49). When analyzed on an OM basis, however, calves offered lick tubs had a numerically higher supplement efficiency (50.4%) in comparison to calves …

Feedlot Manure Management Considerations Including Anaerobic Digestion Potential And Mineral Retention, Andrea K. Watson

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

Three anaerobic digestion trials were conducted to evaluate methane production from feedlot manure. As organic matter content of manure decreased, degradation of manure and methane production also linearly decreased (P ≤ 0.02). Quality, or organic matter content of manure, had a greater impact on anaerobic digestion than diet (with and without distillers grains) fed to cattle. Minerals are concentrated in effluent removed from anaerobic digesters.

Knowing mineral retention within cattle allows for more accurate calculation of mineral excretion in manure. Three serial slaughter trials measured mineral retention in growing and finishing cattle. During a growing phase, beef cattle gaining …

Volatile Organic Compound Flux From Manure Of Cattle Fed Diets Differing In Grain Processing Method And Co-Product Inclusion, Kristin Hales, David B. Parker, N. Andy Cole

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

Odor emissions from livestock production have become increasingly important in the past decade. Odors derived from animal feeding operations are caused by odorous VOC emitted from the mixture of feces and urine, as well as feed and silage which may be experiencing microbial fermentation. Distillers grains are a by-product of corn grain fermentation used to produce fuel ethanol, and this industry has grown rapidly throughout the U.S. in past years. Therefore, the use of wet distillers grains with solubles (WDGS) in feedlot cattle diets has also increased. The objective of this research was to determine specific VOC emissions from feces …

Effect Of Conditioned Medium On The Recovery Of Dormant Mycobacteria In Culture, Kelly E. Rock

Journal of Undergraduate Research at Minnesota State University, Mankato

Mycobacterium avium subsp. paratuberculosis (Mpt) is the etiologic agent of Johne’s disease, a chronic intestinal disease in cattle that threatens the economic viability of dairy farming. Diagnostic culture is typically unrewarding until several years after infection when clinical signs can be observed. This leads to widespread infection within the herd. Difficulty in culturing Mpt may be a result of oxidative damage due to the increased metabolic rate when dormant organisms are recovered in a nutrient rich medium. In order to improve recovery it is believed that some organisms secrete a growth factor in times of environmental stress which enables them …

Feeding Alkaline Treated And Processed Crop Residue To Feedlot Cattle, Sarah Jean Peterson

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

Chemical treatment and decreased particle size are methods used to improve digestibility and utilization of the available nutrients in low quality forages. Previous research has indicated that chemically treated corn residue can take the place of corn when included in finishing rations containing distillers grains. Also, decreasing particle size utilizing methods such as pelleting has been shown to improve DMI and ADG. However, limited research has been completed on use of chemical treatment and pelleting in growing and receiving rations. Also, an ideal distillers inclusion has not yet been identified when including alkaline treated stalks in finishing rations. Therefore, a …

Determining Forage Intake Of Nursing Calves Grazing Native Sandhills Rangeland, Jennifer A. Walker

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

Effective management of grazing lands is important for longevity and productivity. Accurate calculations of stocking rates per animal unit will aid in long term sustainability. Calculating stocking rates for cattle can prove challenging for cows and nursing calves. Limited research has been conducted to determine forage intake of the nursing calf pre-weaning. The objective of Trial 1 was to determine nursing calf forage intake over time until weaning. Trial 1 used 8 crossbred cow-calf pairs in experiment 1 and 12 pairs in experiment 2. Pairs were separated into two groups rotating between grazing upland range or housed in individual pens …

Effects Of Condensed Tannins On The Toxicity Of Fireweed (Senecio Madagascariensis) To Cattle, Carolyn L. Wong

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fireweed (Senecio madagascariensis) is a noxious and invasive weed affecting pastures in Hawaii, Australia, and South America. Fireweed contains compounds called pyrrolizidine alkaloids that are toxic to most grazing mammals. Toxic effects to cattle include irreversible damage to liver cells, hardening of the liver, and loss of liver function, which may lead to jaundice, swelling, and the accumulation of fluids in the stomach and other physiological malfunctions. External effects include rough appearance, diarrhea, low energy and dullness, photosensitization, and abnormal behavior, many of which can lead to death. Fireweed also can reduce pasture productivity by as much as …

Methods Of Bovine Reproduction, Kelsey L. O'Donnell

Honors Scholar Theses

The beef and dairy cattle industries are of immense economic value in the United States and have made impressive advancements over the past century. Their success depends strongly upon the reproductive efficiency of their breeding programs. This overview discusses the major advancements in bovine reproduction that have been integrated into the beef and dairy cattle industries and also the emerging technologies that are currently being researched. Current practices like artificial insemination and estrus synchronization resulted from the development of a strong understanding of cattle physiology and the endocrinology of the estrous cycle. With these technologies, selection of superior genetic traits …