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Full-Text Articles in Beef Science

2026 Nebraska Beef Cattle Report Jan 2026

2026 Nebraska Beef Cattle Report

Nebraska Beef Cattle Reports

The 2026 Nebraska Beef Cattle Report brings together applied research, emerging technologies, and management insights that directly address the evolving challenges and opportunities facing today’s beef industry. This year’s collection includes 36 articles that span the full beef production system, from cow/calf and forage management to feedlot nutrition, animal health, behavior, meat quality, and sustainability, providing science-based guidance grounded in real-world production contexts.

Cow/Calf Nutrition, Reproduction, and Management

This section highlights management strategies that influence reproductive success and long-term herd performance. Articles focus on late-gestation heifer nutrition and practical applications of artificial insemination to support efficient, productive cow/calf systems.

Forage, …


Comparison Of Spayed Heifer Performance To Intact Heifers Fed Melengestrol Acetate On Feedlot Performance And Carcass Characteristics, Tate S. Johnson, Rebecca L. Mcdermott, Halden J. Clark, Jim C. Macdonald, Jessica L. Sperber Jan 2026

Comparison Of Spayed Heifer Performance To Intact Heifers Fed Melengestrol Acetate On Feedlot Performance And Carcass Characteristics, Tate S. Johnson, Rebecca L. Mcdermott, Halden J. Clark, Jim C. Macdonald, Jessica L. Sperber

Nebraska Beef Cattle Reports

Summary with Implications

Pregnancy and estrous cycle management are critical considerations when feeding intact heifers in the feedyard. Alternatively, producers can opt to spay heifers, which eliminates hormonal fluctuations associated with the estrous cycle. A proportion of U.S. feedlots have spayed heifers on feed, although there is limited data comparing the performance of spayed heifers to intact heifers. A commercial feedlot experiment was conducted to compare performance between spayed and intact heifers fed melengestrol acetate. Intact heifers had greater ADG and tended to have greater DMI compared to spayed heifers, although no difference in feed conversion was observed. Carcass weight …


Effect Of Ovarian Characteristics And Propylene Glycol Supplementation On Pregnancy Rates Per Ai In Suckled Beef Cows Subjected To A 7-Day Co-Synch Fixed-Time Ai Protocol Across Seasons, Body Condition Scores, And Postpartum Intervals, Pachara Pearodwong, Sarawanee Khunmanee, Kajohn Nitiwararuk, Thuwanon Boonkerd, Thananon Junsuri, Andrew A. Ponter, Winai Kaewlamun Dec 2025

Effect Of Ovarian Characteristics And Propylene Glycol Supplementation On Pregnancy Rates Per Ai In Suckled Beef Cows Subjected To A 7-Day Co-Synch Fixed-Time Ai Protocol Across Seasons, Body Condition Scores, And Postpartum Intervals, Pachara Pearodwong, Sarawanee Khunmanee, Kajohn Nitiwararuk, Thuwanon Boonkerd, Thananon Junsuri, Andrew A. Ponter, Winai Kaewlamun

The Thai Journal of Veterinary Medicine

The present study evaluated the independent effects of ovarian characteristics and oral propylene glycol (PG) supplementation on pregnancy rates in suckled beef cows subjected to the 7-day CO-Synch + CIDR fixed-time AI (FTAI) protocol across different seasons, body condition scores (BCS; 5-point scale), and parturition-to-FTAI intervals. Cows received a CIDR insert and 10 μg GnRH on day -10, followed by 25 mg PGF2α at CIDR removal on day -3, and another 10 μg GnRH 72 h later (day 0). In Study 1, the ovarian characteristics of 36 cows were assessed transrectally on days -10 and 0 relative to the FTAI. …


Recovery And Characterization Of Moraxella Species From Bovine Specimens, Laura G. Leger Dec 2025

Recovery And Characterization Of Moraxella Species From Bovine Specimens, Laura G. Leger

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

The family Moraxellaceae is made up of a diverse group of 24 named species that fall into three phylogenetic groups. While most Moraxella spp. act as commensal respiratory and/or ocular flora of mammals, some are associated with disease. One of these diseases, infectious bovine keratoconjunctivitis (IBK), has significant welfare and economic impacts to both cattle and cattle producers. Moraxella bovis is the only experimentally determined cause of IBK, however, an association of Moraxella bovoculi with disease has been proposed. Currently, available vaccines do not have high levels of efficacy in the field. Culture based methods are the gold standard for …


Environmental Effects On Preweaning Calf Health, Lindsay L. Waechter-Mead May 2025

Environmental Effects On Preweaning Calf Health, Lindsay L. Waechter-Mead

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

Neonatal calf health is an important factor in the productivity and profitability in the beef cattle industry, influencing preweaning survival, growth, and long-term performance. The overall objective of this thesis is to characterize risk factors that contribute to health issues in young beef calves. The first objective is to review literature exploring the environmental factors affecting preweaning morbidity and mortality, including hypothermia, precipitation, and wind. Management strategies such as the effect of environmental conditions of calving location, body condition score in dams at parturition, and the impacts of dystocia on calf health will also be discussed. Gaps in current research …


Stomoxys Flies (Diptera, Muscidae) Are Competent Vectors Of Trypanosoma Evansi, Trypanosoma Vivax, And Other Livestock Hemopathogens, Julia W. Muita, Joel L. Bargul, John Mark O. Makwatta, Ernest M. Ngatia, Simon K. Tawich, Daniel K. Masiga, Merid N. Getahun May 2025

Stomoxys Flies (Diptera, Muscidae) Are Competent Vectors Of Trypanosoma Evansi, Trypanosoma Vivax, And Other Livestock Hemopathogens, Julia W. Muita, Joel L. Bargul, John Mark O. Makwatta, Ernest M. Ngatia, Simon K. Tawich, Daniel K. Masiga, Merid N. Getahun

All Peer-Reviewed Publications

Stomoxys flies are widely distributed and economically significant vectors of various livestock pathogens of veterinary importance. However, the role of Stomoxys spp. in pathogen transmission is poorly understood. Therefore, we studied the feeding patterns of these blood feeders collected from specific locations in Kenya to identify various vertebrate hosts they fed on, the livestock hemopathogens they carried, and to elucidate their role in pathogens transmission. Our findings show that field-collected Stomoxys flies carried several pathogens, including Trypanosoma spp., Anaplasma spp., and Theileria spp., which were also detected in the blood of sampled livestock, namely camels and cattle. The findings on …


Artificial Insemination Of Beef Heifers With Multi-Sire Semen, Dempster Christenson, Jordan M. Thomas, Daniel J. Kelly, Richard N. Funston Jan 2025

Artificial Insemination Of Beef Heifers With Multi-Sire Semen, Dempster Christenson, Jordan M. Thomas, Daniel J. Kelly, Richard N. Funston

Nebraska Beef Cattle Reports

This study compared pregnancy rates of beef heifers artificially inseminated with multi-sire semen to single-sire semen. It was hypothesized pregnancy rates resulting from multi-sire semen would be increased compared to single-sire semen. Heifers were artificially inseminated with semen from one of three single-sires or semen from a combination of the same three sires. Pregnancy rates did not significantly differ. Paternity testing suggests sire parentage can be unequal when semen is mixed from multiple sires. In summary, producers can expect similar pregnancy rates using single-sire and multi-sire semen, but progeny may have unequal sire representation.


Small Beef-Packer Resilience During The Covid-19 Pandemic: Evidence And Policy Implications, Azzeddine Azzam, Sunil P. Dhoubadel, Binod Khanal Nov 2024

Small Beef-Packer Resilience During The Covid-19 Pandemic: Evidence And Policy Implications, Azzeddine Azzam, Sunil P. Dhoubadel, Binod Khanal

Cornhusker Economics

As part of a larger research project on the economics of beef supply chain resilience to natural disasters, financed in part by a grant from the USDA National Institute of Food and Agriculture, we obtained information from 289 processing plants across the United States about their operations during the peak COVID-19 period of March to June 2020 via a telephone survey. We collected data on plant type (slaughter, processing, both), the dominant livestock processed by the plant (predominantly beef, pork, poultry, and sheep/goat), plant capacity (maximum and typical capacity in slaughter head/day), age of establishment, and, whether the plant ceased, …


Photobiomodulation Of Bovine Oocytes During Maturation Increases Atp Content And Enhances Subsequent Embryonic Development, Kendall Richey May 2024

Photobiomodulation Of Bovine Oocytes During Maturation Increases Atp Content And Enhances Subsequent Embryonic Development, Kendall Richey

All Theses

Bovine in-vitro production(IVP) of embryos is a growing field for producing offspring with desirable genetics in the cattle industries. While IVP is effective, oocyte cytoplasmic maturation is compromised, and bovine oocytes matured in-vitro have reduced metabolic activity than those matured in-vivo. Mitochondria are the central unit of oocyte metabolism, producing ATP through OXPHOS. Photobiomodulation is a light treatment reported to improve metabolic activity. In five experiments, we measured the effects of photobiomodulation treatment with red LED at 16-(L-16) and 20 h(L-20) of bovine oocyte in-vitro maturation on subsequent embryonic development, mitochondrial activity and nuclear progression. Bovine COCs were aspirated …


The Impact Of A Pgym Variant On Myophosphorylase Deficiency In Red Angus Composite Cattle And Changes In The Skeletal Muscle Transcriptome Due To The Intramuscular Administration Of Lidocaine In Wether Lambs, Mackenzie Christin Batt May 2024

The Impact Of A Pgym Variant On Myophosphorylase Deficiency In Red Angus Composite Cattle And Changes In The Skeletal Muscle Transcriptome Due To The Intramuscular Administration Of Lidocaine In Wether Lambs, Mackenzie Christin Batt

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

Project 1 focused on eight calves in a Nebraska herd (composite Simmental, Red Angus, Gelbvieh) that displayed exercise intolerance during forced activity. Available sire pedigrees contained a paternal ancestor within 2-4 generations in all affected calves. Pedigrees of the calves’ dams were unavailable, however, the cows were ranch-raised and retained from prior breeding seasons, where bulls used for breeding occasionally had a common ancestor. Therefore, it was hypothesized that a de novo autosomal recessive variant was causative of exercise intolerance in these calves. A genome-wide association analysis followed by whole-genome sequencing led to the identification of a variant in the …


Impact Of Strategic Postweaning Supplementation On March- And May-Born Yearling Range Heifer And Calf Growth And Performance In The Nebraska Sandhills, Josie Nicole Crouch May 2024

Impact Of Strategic Postweaning Supplementation On March- And May-Born Yearling Range Heifer And Calf Growth And Performance In The Nebraska Sandhills, Josie Nicole Crouch

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

Three experiments were conducted at the Gudmundsen Sandhills laboratory near Whitman, Nebraska. Experiment 1, a retrospective regression analysis, evaluated the impact of heifer percentage of mature body weight (BW) at breeding on heifer performance, subsequent pregnancy rates, and calf production. Overall pregnancy rates were greater (P < 0.01) for heifers at 60 to 70% of mature BW than 50 to 55%, with no differences in pregnancy rates (P ≥ 0.15) after 2-years of age. Heifers at 50 to 60% of mature BW had a greater (P = 0.05) proportion give birth in the first 21-d. A higher percentage of mature BW at breeding resulted in greater (P < 0.01) BW at birth and weaning for offspring.

Experiments 2 and 3 were 3-year studies that evaluated the impact …


Artificial Insemination And Fetal Programming In Beef Production Systems, Dempster M. Christenson May 2024

Artificial Insemination And Fetal Programming In Beef Production Systems, Dempster M. Christenson

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

Pregnancy to artificial insemination and late gestation fetal programming of the next calf crop are central to genetic development, reproductive longevity, calf crop productivity, and efficiency of cow/calf ranching. The purposes of this research are to find methods to improve pregnancy rate to artificial insemination, the growth and reproductive health of pregnant heifers, and the productivity of their offspring. In the first of four studies we found that extending the period of progesterone administration in an estrus synchronization protocol did not significantly hasten estrus response or increase pregnancy rate to artificial insemination, but timing of estrus within the melengestrol acetate …


Effect Of Use Of Tsetse Repellant Collar Technology On The Farm Performance And Household Welfare Of Small-Scale Livestock Farmers In Kenya, Beatrice W. Muriithi, Kassie Menale, Gracious M. Diiro, Michael N. Okal, Daniel K. Masiga Jun 2023

Effect Of Use Of Tsetse Repellant Collar Technology On The Farm Performance And Household Welfare Of Small-Scale Livestock Farmers In Kenya, Beatrice W. Muriithi, Kassie Menale, Gracious M. Diiro, Michael N. Okal, Daniel K. Masiga

All Peer-Reviewed Publications

Tsetse-transmitted Animal African Trypanosomosis (AAT) is a disease of economic importance to livestock development in Sub-Saharan Africa. The disease is widely managed using trypanocides that are expensive for smallholders and associated with health risks due to drug residues in animal products and drug resistance. Developed recently by the International Centre of Insect Physiology and Ecology (icipe) and partners, the novel Tsetse repellent collar technology (TRCT) provides an effective alternative control measure that targets the tsetse fly vector of AAT. This study assessed the impact of TRCT on household welfare and food security by using ex-post non-experimental data obtained from 632 …


Identifying Barriers To Data Use On U.S. Beef Cow-Calf Operations And Developing Solutions To Improve Cow-Calf Record-Keeping, William Isaac Jumper May 2023

Identifying Barriers To Data Use On U.S. Beef Cow-Calf Operations And Developing Solutions To Improve Cow-Calf Record-Keeping, William Isaac Jumper

Theses and Dissertations

Cattle health and production records (CHPR) are data collected by cattle producers and veterinarians in the form of measurements, observations, counts of events over time, and physiologic attributes that describe individual and group-level health and production. These data are useful to both veterinarians and cattle producers for making evidence-based decisions on cow-calf operations. Currently, there are no uniform, industry-wide methods of capturing and recording CHPR in the U.S. cow-calf industry. Although many cow-calf producers in the U.S. are thought to collect some form of CHPR, it is believed that relatively few are doing so in an electronic manner that facilitates …


Pharmacokinetics Of Single Feeding Of Cannabidiol In Cattle: A Pilot Study, Haley Cornette Apr 2023

Pharmacokinetics Of Single Feeding Of Cannabidiol In Cattle: A Pilot Study, Haley Cornette

Honors College Theses

Cannabidiol (CBD) is a substance that has been used in complementary medicine for many years. However, modern medicine has little knowledge of how this substance is utilized and metabolized in ruminant animals. Regulations on quality assurance and use in animals are lacking, and CBD supplementation in livestock is not approved. If CBD supplements can be shown to be safe and effective, detection in the animal will be important for determining regulation of use. A withdrawal period can then be established to allow time for deterioration of product to safe levels before livestock products enter human markets. This study sought to …


Epidemiological Survey Of Bovine Babesia And Theileria Parasites In Buffaloes In District Dera Ismail, Khyber Pakhtunkhwa, Waseem Ullah, Arsalan Khan, Akhtar Ali, Imtiaz Ali Shah, Umm E. Aimen, Imtiaz Khan, Abdul Wadood Jan, Saqib Ali Rustam Mar 2023

Epidemiological Survey Of Bovine Babesia And Theileria Parasites In Buffaloes In District Dera Ismail, Khyber Pakhtunkhwa, Waseem Ullah, Arsalan Khan, Akhtar Ali, Imtiaz Ali Shah, Umm E. Aimen, Imtiaz Khan, Abdul Wadood Jan, Saqib Ali Rustam

Journal of Bioresource Management

Piroplasmosis (babesiosis and theileriosis) are the leading blood parasites responsible for significant economic losses to the dairy enterprises. These parasites are transmitted by Ixodid ticks from a diseased animal to a healthy animal. This study was executed to determine the prevalence of Theileria and Babesia in water buffaloes in District Dera Ismail Khan for their risk assessment. During this trial, 350 random blood samples were obtained from buffalos within the region of District Dera Ismail Khan and examined for Babesia and Theileria parasites using Giemsa staining technique under an oil immersion lens. Forty-eight blood samples were found positive and the …


Metabolites From Trypanosome-Infected Cattle As Sensitive Biomarkers For Animal Trypanosomosis, Merid N. Getahun, John Ngiela, John Mark O. Makwatta, Peter Ahuya, Tawich K. Simon, Samuel K. Kamau, Baldwyn Torto, Daniel Masiga Jul 2022

Metabolites From Trypanosome-Infected Cattle As Sensitive Biomarkers For Animal Trypanosomosis, Merid N. Getahun, John Ngiela, John Mark O. Makwatta, Peter Ahuya, Tawich K. Simon, Samuel K. Kamau, Baldwyn Torto, Daniel Masiga

All Peer-Reviewed Publications

Trypanosomes are important global livestock and human pathogens of public health importance. Elucidating the chemical mechanisms of trypanosome-relevant host interactions can enhance the design and development of a novel, next-generation trypanosomosis diagnostics. However, it is unknown how trypanosome infection affects livestock volatile odors. Here, we show that Trypanosoma congolense and Trypanosoma vivax infections induced dihydro-β- ionone and junenol, while abundance of dihydro-α-ionone, phenolics, p-cresol, and 3-propylphenol significantly elevated in cow urine. These biomarkers of trypanosome infection are conserved in cow breath and the urine metabolites of naturally infected cows, regardless of population, diet, or environment differences. Furthermore, treating trypanosome-infected cows …


Molecular Detection Of Novel Anaplasma Sp. And Zoonotic Hemopathogens In Livestock And Their Hematophagous Biting Keds (Genus Hippobosca) From Laisamis, Northern Kenya, Daniel M. Mwaki, Kevin O. Kidambasi, Johnson Kinyua, Kenneth Ogila, Collins Kigen, Dennis Getange, Jandouwe Villinger, Daniel K. Masiga, Mark Carrington, Joel L. Bargul Jan 2022

Molecular Detection Of Novel Anaplasma Sp. And Zoonotic Hemopathogens In Livestock And Their Hematophagous Biting Keds (Genus Hippobosca) From Laisamis, Northern Kenya, Daniel M. Mwaki, Kevin O. Kidambasi, Johnson Kinyua, Kenneth Ogila, Collins Kigen, Dennis Getange, Jandouwe Villinger, Daniel K. Masiga, Mark Carrington, Joel L. Bargul

All Peer-Reviewed Publications

Background: Livestock are key sources of livelihood among pastoral communities. Livestock productivity is chiefly constrained by pests and diseases. Due to inadequate disease surveillance in northern Kenya, little is known about pathogens circulating within livestock and the role of livestock-associated biting keds (genus Hippobosca) in disease transmission. We aimed to identify the prevalence of selected hemopathogens in livestock and their associated blood-feeding keds. Methods: We randomly collected 389 blood samples from goats (245), sheep (108), and donkeys (36), as well as 235 keds from both goats and sheep (116), donkeys (11), and dogs (108) in Laisamis, Marsabit County, northern Kenya. …


An Update On The Distribution Of Glossina (Tsetse Flies) At The Wildlife-Human-Livestock Interface Of Akagera National Park, Rwanda, Richard S. Gashururu, Samuel M. Githigia, Methode N. Gasana, Richard Habimana, Ndichu Maingi, Giuliano Cecchi, Massimo Paone, Weining Zhao, Daniel K. Masiga, James Gashumba Dec 2021

An Update On The Distribution Of Glossina (Tsetse Flies) At The Wildlife-Human-Livestock Interface Of Akagera National Park, Rwanda, Richard S. Gashururu, Samuel M. Githigia, Methode N. Gasana, Richard Habimana, Ndichu Maingi, Giuliano Cecchi, Massimo Paone, Weining Zhao, Daniel K. Masiga, James Gashumba

All Peer-Reviewed Publications

Background: Glossina (tsetse flies) biologically transmit trypanosomes that infect both humans and animals. Knowledge of their distribution patterns is a key element to better understand the transmission dynamics of trypanosomosis. Tsetse distribution in Rwanda has not been well enough documented, and little is known on their current distribution. This study determined the current spatial distribution, abundance, diversity, and seasonal variations of tsetse flies in and around the Akagera National Park. Methods: A longitudinal stratified sampling following the seasons was used. Biconical traps were deployed in 55 sites for 6 consecutive days of each study month from May 2018 to June …


Occurrence, Diversity And Distribution Of Trypanosoma Infections In Cattle Around The Akagera National Park, Rwanda, S. Richard Gashururu, Ndichu Maingi, Samuel M. Githigia, Methode N. Gasana, Peter O. Odhiambo, Dennis O. Getange, Richard Habimana, Giuliano Cecchi, Weining Zhao, James Gashumba, Joel L. Bargul, Daniel K. Masiga Dec 2021

Occurrence, Diversity And Distribution Of Trypanosoma Infections In Cattle Around The Akagera National Park, Rwanda, S. Richard Gashururu, Ndichu Maingi, Samuel M. Githigia, Methode N. Gasana, Peter O. Odhiambo, Dennis O. Getange, Richard Habimana, Giuliano Cecchi, Weining Zhao, James Gashumba, Joel L. Bargul, Daniel K. Masiga

All Peer-Reviewed Publications

Background African Trypanosomiases threaten the life of both humans and animals. Trypanosomes are transmitted by tsetse and other biting flies. In Rwanda, the African Animal Trypanosomiasis (AAT) endemic area is mainly around the tsetse-infested Akagera National Park (NP). The study aimed to identify Trypanosoma species circulating in cattle, their genetic diversity and distribution around the Akagera NP. Methodology A cross-sectional study was carried out in four districts, where 1,037 cattle blood samples were collected. The presence of trypanosomes was determined by microscopy, immunolog-ical rapid test VerY Diag and PCR coupled with High-Resolution Melt (HRM) analysis. A parametric test (ANOVA) was …


Prevalence Of Trypanosome Species In Cattle Near Ruma National Park, Lambwe Valley, Kenya: An Update From The Historical Focus For African Trypanosomosis, Shewit Kalayou, Michael Nyang Anga Okal, Peter Otieno Odhiambo, Kawira Mathenge, Daniel Ochieng Gamba, Edward Kariuki, Francis Mcodimba, Daniel Masiga Nov 2021

Prevalence Of Trypanosome Species In Cattle Near Ruma National Park, Lambwe Valley, Kenya: An Update From The Historical Focus For African Trypanosomosis, Shewit Kalayou, Michael Nyang Anga Okal, Peter Otieno Odhiambo, Kawira Mathenge, Daniel Ochieng Gamba, Edward Kariuki, Francis Mcodimba, Daniel Masiga

All Peer-Reviewed Publications

The effective control of diseases in areas shared with wildlife depends on the validity of the epidemiologic parameters that guide interventions. Epidemiologic data on animal trypanosomosis in Lambwe valley are decades old, and the recent suspected outbreaks of the disease in the valley necessitate the urgent bridging of this data gap. This cross-sectional study estimated the prevalence of bovine trypanosomosis, identified risk factors, and investigated the occurrence of species with zoonotic potential in Lambwe valley. The area is ~324 km2, of which 120 km2 is the Ruma National Park. Blood was sampled from the jugular and marginal ear veins of …


Molecular Characterization Of Trypanosoma Vivax In Tsetse Flies Confirms The Presence Of The Virulent Tvv4 Genotype In Kenya: Potential Implications For The Control Of Trypanosomiasis In Shimba Hills, Faith I. Ebhodaghe, Armanda D.S. Bastos, Kevin O. Kidambasi, Shewit Kalayou, Daniel K. Masiga, Michael N. Okal Sep 2021

Molecular Characterization Of Trypanosoma Vivax In Tsetse Flies Confirms The Presence Of The Virulent Tvv4 Genotype In Kenya: Potential Implications For The Control Of Trypanosomiasis In Shimba Hills, Faith I. Ebhodaghe, Armanda D.S. Bastos, Kevin O. Kidambasi, Shewit Kalayou, Daniel K. Masiga, Michael N. Okal

All Peer-Reviewed Publications

Trypanosoma vivax is a vector-borne protozoan parasite of livestock endemic to Africa and South America. To date, fifteen genotypes of the parasite have been described in vertebrate and insect hosts in East Africa. However, information regarding T. vivax diversity remains limited in many endemic countries in the sub-region, including Kenya. Such information could deepen insight into the local epidemiology of animal trypanosomiasis in Shimba Hills, a wildlife area in southeast Kenya where T. vivax is endemic and infects livestock. We employed two-gene conventional-PCR-sequencing and phylogenetic analysis to characterize T. vivax genotypes in tsetse flies collected between November 2018 and September …


Engineering And Characterization Of Human Β-Defensin-3 And Its Analogues And Microcin J25 Peptides Against Mannheimia Haemolytica And Bovine Neutrophils, Harpreet Dhingra, Kamaljit Kaur, Baljit Singh Jun 2021

Engineering And Characterization Of Human Β-Defensin-3 And Its Analogues And Microcin J25 Peptides Against Mannheimia Haemolytica And Bovine Neutrophils, Harpreet Dhingra, Kamaljit Kaur, Baljit Singh

Pharmacy Faculty Articles and Research

Mannheimia haemolytica-induced bovine respiratory disease causes loss of millions of dollars to Canadian cattle industry. Current antimicrobials are proving to be ineffective and leave residues in meat. Antimicrobial peptides (AMPs) may be effective against M. haemolytica while minimizing the risk of drug residues. Cationic AMPs can kill bacteria through interactions with the anionic bacterial membrane. Human β-Defensin 3 (HBD3) and microcin J25 (MccJ25) are AMPs with potent activity against many Gram-negative bacteria. We tested the microbicidal activity of wild-type HBD3, three HBD3 peptide analogues (28 amino acid, 20AA, and 10AA) derived from the sequence of natural HBD3, and MccJ25 …


Exploring How Maternal Phosphorus Status Affects Calf Growth And Performance, Elizabeth Lafferty May 2021

Exploring How Maternal Phosphorus Status Affects Calf Growth And Performance, Elizabeth Lafferty

Animal Science Undergraduate Honors Theses

This study will focus on how maternal phosphorus status of beef heifers affects the growth and performance of their calves. Heifers have been offered free-choice mineral with either 0 or 4% supplemental phosphorus from 30 days after weaning until calving. A study by H. Hilfiker, a University of Arkansas honors student, investigated the effects of these treatments from 30 days after weaning until 60 days after the breeding season when heifers were confirmed to be bred or open. For this developing heifer project 64 crossbred Angus heifers were assigned randomly into 8 groups (8 heifers/ group) before assigning each group …


Are The Current Animal Trypanosomiasis Management Methods In Kenya Complementary Or Substitutes? Evidence From Kwale County, Arnold Lumumbah Musungu, David Jakinda Otieno, Beatrice Wambui Muriithi, Rose Nyikal, Daniel Masiga, Michael Nyanganga Okal Mar 2021

Are The Current Animal Trypanosomiasis Management Methods In Kenya Complementary Or Substitutes? Evidence From Kwale County, Arnold Lumumbah Musungu, David Jakinda Otieno, Beatrice Wambui Muriithi, Rose Nyikal, Daniel Masiga, Michael Nyanganga Okal

All Peer-Reviewed Publications

African animal trypanosomiasis (AAT) and its vectors, mainly tsetse, are a major constraint to livestock production in sub-Saharan Africa (SSA). Control efforts have been ongoing for decades, but finding a sustainable solution remains a major concern. This paper assessed the complementarity and substitutability of existing AAT management methods to inform policies toward an integrated approach. A multivariate probit (MVP) analytical technique was used to model interrelationships in the control methods from 308 randomly selected livestock keepers. The results show that the current AAT control methods are complementary and not substitutes. Furthermore, the number of years of formal education, household size, …


Tsetse Blood-Meal Sources, Endosymbionts And Trypanosome-Associations In The Maasai Mara National Reserve, A Wildlife-Human-Livestock Interface, Edward Edmond Makhulu, Jandouwe Villinger, Vincent Owino Adunga, Maamun M. Jeneby, Edwin Murungi Kimathi, Enock Mararo, Joseph Wang’Ang’A Oundo, Ali Abdulahi Musa, Lillian Wambua Jan 2021

Tsetse Blood-Meal Sources, Endosymbionts And Trypanosome-Associations In The Maasai Mara National Reserve, A Wildlife-Human-Livestock Interface, Edward Edmond Makhulu, Jandouwe Villinger, Vincent Owino Adunga, Maamun M. Jeneby, Edwin Murungi Kimathi, Enock Mararo, Joseph Wang’Ang’A Oundo, Ali Abdulahi Musa, Lillian Wambua

All Peer-Reviewed Publications

African trypanosomiasis (AT) is a neglected disease of both humans and animals caused by Trypanosoma parasites, which are transmitted by obligate hematophagous tsetse flies (Glossina spp.). Knowledge on tsetse fly vertebrate hosts and the influence of tsetse endo-symbionts on trypanosome presence, especially in wildlife-human-livestock interfaces, is limited. We identified tsetse species, their blood-meal sources, and correlations between endosymbionts and trypanosome presence in tsetse flies from the trypanosome-endemic Maasai Mara National Reserve (MMNR) in Kenya. Among 1167 tsetse flies (1136 Glossina pallidipes, 31 Glossina swynnertoni) collected from 10 sampling sites, 28 (2.4%) were positive by PCR for trypanosome DNA, most (17/28) …


Biogeography Of The Bovine Respiratory Microbiome And Its Relationship With Bovine Respiratory Disease, Jianmin Chai Dec 2020

Biogeography Of The Bovine Respiratory Microbiome And Its Relationship With Bovine Respiratory Disease, Jianmin Chai

Graduate Theses and Dissertations

Bovine respiratory disease (BRD) is the most common and costly disease in the beef cattle industry, leading to high morbidity, mortality and huge economic loss. Despite the recent advances in vaccination and antimicrobial techniques, no significant health-improved outcomes have developed. Due to a deep investigation of the microbiome, respiratory microbiotas are known to have important roles for host health and disease. However, BRD specific pathogens have not yet been identified since they are found in both healthy and diseased animals. A systemic and comprehensive study of the biogeography of the bovine respiratory microbiome and its relationship with BRD is lacking …


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 May 2020

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 …


Associations Among Beef Cattle Genotypes, Neospora Caninum Infection, And Reproductive Performance, Ryan James Page May 2020

Associations Among Beef Cattle Genotypes, Neospora Caninum Infection, And Reproductive Performance, Ryan James Page

Graduate Theses and Dissertations

Reproductive performance is crucial for sustained financial success in the beef cattle industry. This dissertation includes a population study that quantified the incidence of Neospora caninum infections in the central region of the United States and tested its relationship with reproductive performance in beef cattle. Trial one of that study concluded that 6.9% of open, replacement heifers (n = 1306) tested seropositive. The second trial in that project found that 9.6% of the breeding age females (n = 500) tested were seropositive for Neospora caninum; and that state in which the cattle lived and age impacted (P < 0.05) infection rate. Breed composition, number of farm dogs on the ranch, and use of total mixed rations were not associated (P > 0.1) with seropositive …


High Risk For Human Exposure To Rift Valley Fever Virus In Communities Living Along Livestock Movement Routes: A Cross-Sectional Survey In Kenya, Caroline Tigoi, Rosemary Sang, Edith Chepkorir, Benedict Orindi, Samuel Okello Arum, Francis Mulwa, Gladys Mosomtai, Samson Limbaso, Osama A. Hassan, Zephania Irura, Clas Ahlm, Magnus Evander Feb 2020

High Risk For Human Exposure To Rift Valley Fever Virus In Communities Living Along Livestock Movement Routes: A Cross-Sectional Survey In Kenya, Caroline Tigoi, Rosemary Sang, Edith Chepkorir, Benedict Orindi, Samuel Okello Arum, Francis Mulwa, Gladys Mosomtai, Samson Limbaso, Osama A. Hassan, Zephania Irura, Clas Ahlm, Magnus Evander

All Peer-Reviewed Publications

Introduction Multiple outbreaks of Rift Valley Fever (RVF) with devastating effects have occurred in East Africa. These outbreaks cause disease in both livestock and humans and affect poor households most severely. Communities living in areas practicing nomadic livestock movement may be at higher risk of infection. This study sought to i) determine the human exposure to Rift Valley fever virus (RVFV) in populations living within nomadic animal movement routes in Kenya; and ii) identify risk factors for RVFV infection in these communities. Methods A cross-sectional descriptive study design was used. Samples were collected from the year 2014 to 2015 in …