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Adding Parasite Resistance To A Hair Sheep Breeding Objective, Bob Forbes May 2024

Adding Parasite Resistance To A Hair Sheep Breeding Objective, Bob Forbes

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

The U.S. Hair Sheep Index was designed to increase total weight of lamb weaned per ewe lambing (TW) using estimated breeding values (EBV) for direct (DWWT) and maternal (MWWT) weaning weight, and number of lambs born (NLB) and weaned (NLW), as selection criteria. Producers are interested in adding post-weaning fecal egg count EBV (PFEC), an indicator of parasite resistance, to the index to achieve genetic change in both TW and PFEC.

First, the effects of adding PFEC alongside TW to the breeding objective of indexes that used either phenotypes or EBV as selection criteria were studied. Since MWWT is …


Tame The Flame: Inflammation Is A Targetable Physiological Mechanism Underlying Poor Outcomes Of Heat Stress In Finishing Sheep, Pablo C. Grijalva Dec 2023

Tame The Flame: Inflammation Is A Targetable Physiological Mechanism Underlying Poor Outcomes Of Heat Stress In Finishing Sheep, Pablo C. Grijalva

Dissertations and Doctoral Documents from University of Nebraska-Lincoln, 2023–

This research focused on health management through the identification of suitable interventions in stressed livestock. For this investigation, we conducted two experiments. First, we determined whether administration of dexamethasone or fish oil to heat-stressed livestock to reduce systemic inflammation would mitigate metabolic deficits, enhance nutrient utilization, and improve health. We found that these interventions helped to reduce circulating inflammatory cytokines and improve respiration, muscle glucose metabolism, lipid homeostasis, cardiovascular function, and organ pathology in lambs exposed to 30 days of heat stress. In our second experiment, we performed transcriptomic analyses to identify the underlying mechanisms affecting young offspring following prenatal …


Genotype By Environment Interaction And Heteroscedasticity Influence The Expression Of Parasite Resistance In Katahdin Sheep, Brian C. Arisman, Joan M. Burke, James L. M. Morgan, Ronald M. Lewis Jul 2023

Genotype By Environment Interaction And Heteroscedasticity Influence The Expression Of Parasite Resistance In Katahdin Sheep, Brian C. Arisman, Joan M. Burke, James L. M. Morgan, Ronald M. Lewis

Department of Animal Science: Faculty Publications

Increasingly, sheep producers are choosing breeds that express resistance to gastrointestinal parasites due to reduced efficacy of anthelminthic drugs. One such breed is Katahdin. Katahdins are raised in various climates and management systems in the United States, which can be combined into eco-management clusters to describe production environments more holistically. The objectives of this study were to determine if genotype by environment interaction (G × E) and heteroscedasticity existed across these eco-management clusters for traits indicative of parasite resistance. Body weights (BW), FAMACHA scores (FAM), and fecal egg counts (FEC) were collected at around 90 d in 3,527 Katahdin lambs …


Clustering Climate And Management Practices To Define Environmental Challenges Affecting Gastrointestinal Parasitism In Katahdin Sheep, Brian C. Arisman, Joan M. Burke, James L. M. Morgan, Ronald M. Lewis Jan 2023

Clustering Climate And Management Practices To Define Environmental Challenges Affecting Gastrointestinal Parasitism In Katahdin Sheep, Brian C. Arisman, Joan M. Burke, James L. M. Morgan, Ronald M. Lewis

Department of Animal Science: Faculty Publications

Gastrointestinal nematodes (GIN) negatively affect the performance and well-being of sheep. Due to anthelmintic resistance, GIN are difficult to control leading producers to choose breeds that can exhibit resistance to parasitism. An example is Katahdin sheep. Katahdins are raised in various climates and management systems in the United States. These environmental factors can be combined to form eco-management groupings or clusters. We hypothesized that GIN challenge varies predictably based on the characteristics of these environmental clusters. Forty Katahdin producers from across the United States were surveyed for management information, with body weights (BW), fecal egg counts (FEC), and FAMACHA scores …


Environmental Determination Of Gastrointestinal Parasitism In Katahdin Sheep, Brian Arisman Dec 2022

Environmental Determination Of Gastrointestinal Parasitism In Katahdin Sheep, Brian Arisman

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

Gastrointestinal nematodes (GIN) negatively affect the performance and wellbeing of sheep and are difficult to control due to anthelmintic resistance. Producers are therefore choosing breeds naturally resistant to GIN infection, such as the Katahdin. Katahdin are raised in various climates and management systems in the U.S., and those environmental factors can be combined into eco-management clusters. We hypothesized that GIN challenge varies predictably based on the characteristics of these clusters. Katahdin producers from across the U.S. were surveyed for management information. Body weights (BW), fecal egg counts (FEC) and FAMACHA scores (FAM) were collected on 3,527 Katahdin lambs around 90 …


The Effects Of Poor Maternal Nutrition During Gestation In Sheep On The Reproductive Efficiency Of The Offspring, Morgan Dougherty May 2022

The Effects Of Poor Maternal Nutrition During Gestation In Sheep On The Reproductive Efficiency Of The Offspring, Morgan Dougherty

Honors Scholar Theses

Poor maternal nutrition during gestation negatively impacts fetal programming and the development of the hypothalamic-pituitary-ovarian axis in the offspring. Reproductive health of ewes can be characterized by concentrations of reproductive hormones including follicle stimulating hormone (FSH), luteinizing hormone (LH), and progesterone, particularly during the estrous cycle. We hypothesized that ewes born to dams that experienced poor maternal nutrition during gestation would have reduced reproductive capability and efficiency. This means that they would take longer to become pregnant and have reduced concentrations of reproductive hormones compared with those born to mothers fed the control diet. Pregnant dams (F0) were fed one …


Effects Of Increasing Dietary Zinc Sulfate Fed To Gestating Ewes: Ii. Milk Somatic Cell Count, Microbial Populations, And Fatty Acid Composition, C. M. Page, R. M. Knuth, T. W. Murphy, D. C. Rule, B. Bisha, J. B. Taylor, W. C. Stewart Jan 2022

Effects Of Increasing Dietary Zinc Sulfate Fed To Gestating Ewes: Ii. Milk Somatic Cell Count, Microbial Populations, And Fatty Acid Composition, C. M. Page, R. M. Knuth, T. W. Murphy, D. C. Rule, B. Bisha, J. B. Taylor, W. C. Stewart

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

Objective: The objective of the research was to evaluate the effects of increasing dietary Zn sulfate concentration for primiparous gestating ewes on subsequent milk SCC, intramammary microbial identifications, and fatty acid composition.

Materials and Methods: Commercial white-face (WF; n = 27) and black-face (BF; n = 24) ewes (age ≈18 mo; BW = 87.48 ± 8.37 kg) were sorted into breed-type groups and within groups ranked by BW, and then, they were randomly divided into 3 dietary supplement treatment groups: CON (n = 13; 40 mg/kg Zn; ≈1 × NASEM recommendations), Zn500 (n = 21; 500 mg/kg Zn; …


Sheep And Goat Industry Funding Scheme Annual Report 2020/2021, Department Of Primary Industries And Regional Development, Western Australia Jan 2022

Sheep And Goat Industry Funding Scheme Annual Report 2020/2021, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity published reports

The Sheep and Goat Industry Funding Scheme (IFS) has been operating since 2010 to address biosecurity threats relevant to the Western Australian (WA) sheep and goat industry. The Scheme was established by regulation under the Biosecurity and Agriculture Management Act 2007 to enable sheep and goat producers to identify pest and disease priorities at a whole-of-industry level and raise funds for activities to address these priorities.

There are currently three Industry Funding Schemes in operation. In addition to the Sheep and Goat IFS, there is a Cattle IFS and a Grains, Seeds and Hay IFS. The three IFSs operate in …


Nutritional And Physiological Constraints Contributing To Limitations In Small Intestinal Starch Digestion And Glucose Absorption In Ruminants, Ronald J. Trotta, David L. Harmon, James C. Matthews, Kendall C. Swanson Dec 2021

Nutritional And Physiological Constraints Contributing To Limitations In Small Intestinal Starch Digestion And Glucose Absorption In Ruminants, Ronald J. Trotta, David L. Harmon, James C. Matthews, Kendall C. Swanson

Animal and Food Sciences Faculty Publications

Increased efficiency of nutrient utilization can potentially be gained with increased starch digestion in the small intestine in ruminants. However, ruminants have quantitative limits in the extent of starch disappearance in the small intestine. The objective is to explore the nutritional and physiological constraints that contribute to limitations of carbohydrate assimilation in the ruminant small intestine. Altered digesta composition and passage rate in the small intestine, insufficient pancreatic α-amylase and/or small intestinal carbohydrase activity, and reduced glucose absorption could all be potentially limiting factors of intestinal starch assimilation. The absence of intestinal sucrase activity in ruminants may be related to …


Cranial Cruciate Ligament Desmotomies In Sheep Resulting In Peroneus Tertius Injury, Peter J. Welsh, Crystal G. Collier, Holly M. Clement, Michael N. Vakula, Jeffrey B. Mason Jul 2021

Cranial Cruciate Ligament Desmotomies In Sheep Resulting In Peroneus Tertius Injury, Peter J. Welsh, Crystal G. Collier, Holly M. Clement, Michael N. Vakula, Jeffrey B. Mason

Animal, Dairy, and Veterinary Science Student Research

Surgical destabilization of the stifle joint via cranial cruciate ligament desmotomy (CCLD) is a routine procedure for the study of osteoarthritis (OA). Traditionally performed in rats, rabbits, cats, and dogs, CCLD in sheep provides an opportunity to study the pathology and treatment of joint instability in a species whose stifle better represents the equivalent human femorotibial joint. The surgical approaches for CCLD in sheep are variable and can result in inconsistent outcomes. Eight sheep underwent CCLD for use in a gene therapy study. We report this case in which six of the eight sheep were clinically diagnosed by pathognomonic signs …


Invited Review: Mineral Nutrition Considerations For Extensive Sheep Production Systems, W. C. Stewart, J. D. Scasta, J. B. Taylor, T. W. Murphy, A. A.M. Julian Jun 2021

Invited Review: Mineral Nutrition Considerations For Extensive Sheep Production Systems, W. C. Stewart, J. D. Scasta, J. B. Taylor, T. W. Murphy, A. A.M. Julian

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

Purpose: Our purpose is to discuss contemporary and pertinent considerations related to mineral-supplementation strategies for sheep grazing marginal rangelands in extensively managed production systems. Sources: Grey literature, peer-reviewed literature, and data (published and unpublished) from co-authors were used. Synthesis: Precision trace-mineral nutrition of sheep that are grazing extensive production systems requires a comprehensive understanding of the sheep and the grazing environment. Generally, extensive sheep production systems are found in remote geographical regions composed of marginal rangelands not suitable for cultivated crop farming or improved forages. Sheep production is subject to the accessibility and availability of grazable forage, which may vary …


The Effects Of Poor Maternal Nutrition During Gestation On Colostrum And Milk Quality And Immunoglobulin G Concentrations In Sheep, Alexandra Bettencourt May 2021

The Effects Of Poor Maternal Nutrition During Gestation On Colostrum And Milk Quality And Immunoglobulin G Concentrations In Sheep, Alexandra Bettencourt

Honors Scholar Theses

Maternal over- and under-nutrition have negative effects on the growth and development of offspring. Colostrum and milk are critical to neonatal development, and composition and quality of colostrum and milk may be influenced by maternal factors, including diet. In this study, 46 pregnant ewes received one of three diets, 60% (RES), 100% (CON), or 140% (OVER) of National Research Council (NRC) nutrition requirements for total digestible nutrients from d 30 of gestation until parturition. Colostrum samples were collected within 24 hours of parturition. Milk samples were collected on d 3 and d 21 postpartum. Total solid concentrations of samples were …


Relationships Among Intramammary Health, Udder And Teat Characteristics, And Productivity Of Extensively Managed Ewes, Ryan M. Knuth, Whitney C. Stewart, Joshua B. Taylor, Bledar Bisha, Carl J. Yeoman, Megan L. Van Emon, Thomas W. Murphy Apr 2021

Relationships Among Intramammary Health, Udder And Teat Characteristics, And Productivity Of Extensively Managed Ewes, Ryan M. Knuth, Whitney C. Stewart, Joshua B. Taylor, Bledar Bisha, Carl J. Yeoman, Megan L. Van Emon, Thomas W. Murphy

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

Mastitis is an economically important disease and its subclinical state is difficult to diagnose, which makes mitigation more challenging. The objectives of this study were to screen clinically healthy ewes in order to 1) identify cultivable microbial species in milk, 2) evaluate somatic cell count (SCC) thresholds associated with intramammary infection, and 3) estimate relationships between udder and teat morphometric traits, SCC, and ewe productivity. Milk was collected from two flocks in early (<5 >d) and peak (30 to 45 d) lactation to quantify SCC (n = 530) and numerate cultivable microbial species by culture-based isolation followed by matrix-assisted laser …


Prenatal And Postnatal Nutrition Influence Pancreatic And Intestinal Carbohydrase Activities Of Ruminants, Ronald J. Trotta, Kendall C. Swanson Jan 2021

Prenatal And Postnatal Nutrition Influence Pancreatic And Intestinal Carbohydrase Activities Of Ruminants, Ronald J. Trotta, Kendall C. Swanson

Animal and Food Sciences Graduate Research

In ruminant livestock species, nutrition can play an important role in the long-term programming of gastrointestinal function. Pancreatic and small intestinal digestive enzymes are important for postruminal digestion of carbohydrates and protein. Carbohydrases have been shown to respond to changes in the level of feed intake and the dietary inclusion of specific nutrients, including arginine, butyrate, folic acid, fructose, and leucine. Understanding how diet influences enzyme development and activity during prenatal and postnatal life could lead to the development of dietary strategies to optimize offspring growth and development to increase digestive efficiency of ruminant livestock species. More research is needed …


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 Jan 2021

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 = …


Major Zoonotic Diseases Of Sheep And Meat Goats, Maria Lenira Leite-Browning, Richard Browning Jr., Cassandra F. Vaughn, Kenneth Andries, Marion Simon Jan 2021

Major Zoonotic Diseases Of Sheep And Meat Goats, Maria Lenira Leite-Browning, Richard Browning Jr., Cassandra F. Vaughn, Kenneth Andries, Marion Simon

Extension Publications

No abstract provided.


Biosecurity Measures For Meat Goat And Sheep Managers, Maria Lenira Leite-Browning, Richard Browning Jr., Cassandra F. Vaughn, Kenneth Andries Jan 2021

Biosecurity Measures For Meat Goat And Sheep Managers, Maria Lenira Leite-Browning, Richard Browning Jr., Cassandra F. Vaughn, Kenneth Andries

Extension Publications

No abstract provided.


A Comprehensive Review On Bioactive Peptides Derived From Milk And Milk Products Of Minor Dairy Species, Snigdha Guha, Heena Sharma, Gaurav Kr Deshwal, Priyanka Singh Rao Jan 2021

A Comprehensive Review On Bioactive Peptides Derived From Milk And Milk Products Of Minor Dairy Species, Snigdha Guha, Heena Sharma, Gaurav Kr Deshwal, Priyanka Singh Rao

Department of Food Science and Technology: Faculty Publications

Milk from different species has been exploited for the isolation of various functional ingredients for decades. Irrespective of the source, milk is considered as a complete food, as it provides essential nutrients required by the human body. Proteins and their fractions are valuable sources of bioactive peptides that might exert a health beneficial role in the human body such as immune-modulation, antioxidant activity, ACE-inhibitory activity, anti- neoplastic, anti-microbial, etc. In milk, bioactive peptides may either be present in their natural form or released from their parental proteins due to enzymatic action. The increasing interest in bioactive peptides among researchers has …


Sheep And Goat Industry Funding Scheme Annual Report 2019/2020, Department Of Primary Industries And Regional Development, Western Australia Jan 2021

Sheep And Goat Industry Funding Scheme Annual Report 2019/2020, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity published reports

The Sheep and Goat Industry Funding Scheme (IFS) has been operating since 2010 to address biosecurity threats relevant to the Western Australian (WA) sheep and goat industry. The Scheme was established by regulation under the Biosecurity and Agriculture Management Act 2007 to enable sheep and goat producers to identify pest and disease priorities at a whole-of-industry level and raise funds for activities to address these priorities.

There are currently three Industry Funding Schemes in operation. In addition to the Sheep and Goat IFS, there is a Cattle IFS and a Grains, Seeds and Hay IFS. The three IFSs operate in …


Crimean-Congo Hemorrhagic Fever Virus Endemicity In United Arab Emirates, 2019, Jeremy V. Camp, Dafalla O. Kannan, Babiker Mohammed Osman, Moayyed Sher Shah, Brigitte Howarth, Tamer Khafaga, Pia Weidinger, Noushad Karuvantevida, Jolanta Kolodziejek, Hessa Mazrooei, Nadine Wolf, Tom Loney, Norbert Nowotny May 2020

Crimean-Congo Hemorrhagic Fever Virus Endemicity In United Arab Emirates, 2019, Jeremy V. Camp, Dafalla O. Kannan, Babiker Mohammed Osman, Moayyed Sher Shah, Brigitte Howarth, Tamer Khafaga, Pia Weidinger, Noushad Karuvantevida, Jolanta Kolodziejek, Hessa Mazrooei, Nadine Wolf, Tom Loney, Norbert Nowotny

All Works

© 2020 Centers for Disease Control and Prevention (CDC). All rights reserved. We conducted a cross-sectional survey of Crimean-Congo hemorrhagic fever virus (CCHFV) in dromedary camels and attached ticks at 3 locations in the United Arab Emirates. Results revealed a high prevalence of CCHFV-reactive antibodies in camels and viral RNA in ticks and camel serum, suggesting the virus is endemic in this country.


Poor Maternal Nutrition During Gestation Alters Placental Igf-I, Igf-Ii, And Igfbp-3 Mrna Expression In Sheep, Caitlyn Splaine Apr 2020

Poor Maternal Nutrition During Gestation Alters Placental Igf-I, Igf-Ii, And Igfbp-3 Mrna Expression In Sheep, Caitlyn Splaine

Honors Scholar Theses

Insulin-like growth factors (IGF) modulate placental and fetal growth and development through nutrient sensing and endocrine signaling. We hypothesized that poor maternal nutrition during gestation would alter IGF-I, IGF binding protein (IGFBP)-2, and IGFBP-3 mRNA expression in the ovine placenta, but would not affect IGF-II mRNA expression. Pregnant ewes (n=57) were individually fed: 60% (restricted fed; RES), 100% (control fed; CON), or 140% (over fed; OVER) of National Research Council requirements for TDN starting at day 30±0.2 of gestation. Ewes were euthanized and cotyledon and caruncle samples were collected at days 45, 90, and 135 of gestation. Relative mRNA expression …


Sequential Analysis Of Livestock Herding Dog And Sheep Interactions, Jonathan Early, Jessica Alders, Elizabeth R. Arnott, Claire M. Wade, Paul Mcgreevy Feb 2020

Sequential Analysis Of Livestock Herding Dog And Sheep Interactions, Jonathan Early, Jessica Alders, Elizabeth R. Arnott, Claire M. Wade, Paul Mcgreevy

Interactive Behavior Collection

Livestock herding dogs are crucial contributors to Australian agriculture. However, there is a dearth of empirical studies of the behavioural interactions between dog and livestock during herding. A statistical approach that may reveal cause and effect in such interactions is lag sequential analysis. Using 48 video recordings of livestock herding dogs and sheep in a yard trial competition, event-based (time between behaviours is irrelevant) and time-based (time between behaviours is defined) lag sequential analyses identified several significant behavioural interactions (adjusted residuals greater than 2.58; the maximum likelihood-ratio chi-squared statistic for all eight contingency tables identified all sequences as highly significant …


Small Farm Husbandry: Cow, Sheep And Goat For Meat Production, Nicole Burton Jan 2020

Small Farm Husbandry: Cow, Sheep And Goat For Meat Production, Nicole Burton

Sustainability Education Resources

This course provides students with a farmer’s perspective on the sustainable management of cows, sheep and goats on a small farm. The course provides students with a clear understanding of how to think through the planning and management of cows, sheep and goats for meat production. All aspects from purchasing and nutrition to marketing and finances will be addressed. This course also brings awareness to the U.S. meat industry and supports students in becoming educated consumers and producers. Students will walk away with a rudimentary plan on how to incorporate ruminants into their small farm plan.


Comparison Of Sheep, Goats, And Calves As Infection Models For Mycobacterium Avium Subsp. Paratuberculosis, Judith R. Stabel, J. P. Bannantine, Jesse M. Hostetter Jan 2020

Comparison Of Sheep, Goats, And Calves As Infection Models For Mycobacterium Avium Subsp. Paratuberculosis, Judith R. Stabel, J. P. Bannantine, Jesse M. Hostetter

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Animal infection models to study Mycobacterium avium subsp. paratuberculosis (MAP) infection are useful for evaluating the efficacy of vaccines and other therapeutics for the prevention or treatment of infection. The goal of the present study was to compare smaller ruminants, sheep and goats, with calves as infection models. Neonatal sheep, goats, and calves (n = 4) received 109 cfu of a cattle isolate of MAP in milk replacer on days 0, 3 and 6 in a 12-month study and sampled monthly thereafter. Results demonstrated a robust antigen-specific IFN-γ response at 90 days post-inoculation for sheep and goats, with lower responses …


Genetic Structure And Admixture In Sheep From Terminal Breeds In The United States, Kimberly M. Davenport, C. Heimke, S. D. Mc Kay, J. W. Thorne, Ronald M. Lewis, Todd Taylor, B. M. Murdoch Jan 2020

Genetic Structure And Admixture In Sheep From Terminal Breeds In The United States, Kimberly M. Davenport, C. Heimke, S. D. Mc Kay, J. W. Thorne, Ronald M. Lewis, Todd Taylor, B. M. Murdoch

Department of Animal Science: Faculty Publications

Selection for performance in diverse production settings has resulted in variation across sheep breeds worldwide. Although sheep are an important species to the United States, the current genetic relationship among many terminal sire breeds is not well characterized. Suffolk, Hampshire, Shropshire and Oxford (terminal) and Rambouillet (dual purpose) sheep (n = 248) sampled from different flocks were genotyped using the Applied Biosystems Axiom Ovine Genotyping Array (50K), and additional Shropshire sheep (n = 26) using the Illumina Ovine SNP50 BeadChip. Relationships were investigated by calculating observed heterozygosity, inbreeding coefficients, eigenvalues, pairwise Wright’s FST estimates and an identity by state matrix. …


Genome-Wide Association Study To Identify Genetic Loci Associated With Gastrointestinal Nematode Resistance In Katahdin Sheep, G. M. Becker, K. M. Davenport, Joan M. Burke, Ronald M. Lewis, J. E. Miller, J. L.M. Morgan, D. R. Notter, B. M. Murdoch Jan 2020

Genome-Wide Association Study To Identify Genetic Loci Associated With Gastrointestinal Nematode Resistance In Katahdin Sheep, G. M. Becker, K. M. Davenport, Joan M. Burke, Ronald M. Lewis, J. E. Miller, J. L.M. Morgan, D. R. Notter, B. M. Murdoch

Department of Animal Science: Faculty Publications

Resistance to gastrointestinal nematodes has previously been shown to be a moderately heritable trait in some breeds of sheep, but the mechanisms of resistance are not well understood. Selection for resistance currently relies upon faecal egg counts (FEC), blood packed cell volumes and FAMACHA visual indicator scores of anaemia. Identifying genomic markers associated with disease resistance would potentially improve the selection process and provide a more reliable means of classifying and understanding the biology behind resistant and susceptible sheep. A GWAS was conducted to identify possible genetic loci associated with resistance to Haemonchus contortus in Katahdin sheep. Forty animals were …


Genetic Structure And Admixture In Sheep From Terminal Breeds In The United States, Kimberly M. Davenport, C. Hiemke, Stephanie D. Mc Kay, J. W. Thorne, Ronald M. Lewis, Todd Taylor, B. M. Murdoch Jan 2020

Genetic Structure And Admixture In Sheep From Terminal Breeds In The United States, Kimberly M. Davenport, C. Hiemke, Stephanie D. Mc Kay, J. W. Thorne, Ronald M. Lewis, Todd Taylor, B. M. Murdoch

Department of Animal Science: Faculty Publications

Selection for performance in diverse production settings has resulted in variation across sheep breeds worldwide. Although sheep are an important species to the United States, the current genetic relationship among many terminal sire breeds is not well characterized. Suffolk, Hampshire, Shropshire and Oxford (terminal) and Rambouillet (dual purpose) sheep (n = 248) sampled from different flocks were genotyped using the Applied Biosystems Axiom Ovine Genotyping Array (50K), and additional Shropshire sheep (n = 26) using the Illumina Ovine SNP50 BeadChip. Relationships were investigated by calculating observed heterozygosity, inbreeding coefficients, eigenvalues, pairwise Wright’s FST estimates and an identity by state matrix. …


Liver Fluke In Irish Sheep: Prevalence And Associations With Management Practices And Co-Infection With Rumen Fluke, Maria Pia Munita, Rosemary Rea, Et. Al. Nov 2019

Liver Fluke In Irish Sheep: Prevalence And Associations With Management Practices And Co-Infection With Rumen Fluke, Maria Pia Munita, Rosemary Rea, Et. Al.

Department of Biological Sciences Publications

Background

The present study aimed to identify the national prevalence of Fasciola hepatica in Irish sheep and to conduct a risk analysis assessment based on management and treatment practices in participating flocks. Also, co-infection with rumen fluke was quantified and its association with liver fluke and management practices was assessed.

Methods

A total of 305 sheep flocks were selected ensuring even national representation of the sheep population. Participating farms were asked to complete a survey questionnaire on farm management practices and submit faecal samples during the winter of 2014–2015. Pooled faecal samples were analysed for the presence of F. hepatica …


Sheep And Goat Industry Funding Scheme 2018/2019, Department Of Primary Industries And Regional Development, Western Australia Oct 2019

Sheep And Goat Industry Funding Scheme 2018/2019, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity published reports

The Sheep and Goat Industry Funding Scheme (IFS) has been operating since 2010 to address biosecurity threats relevant to the Western Australian (WA) sheep and goat industry. The Scheme was established by regulation under the Biosecurity and Agriculture Management Act 2007 to enable sheep and goat producers to identify pest and disease priorities at a whole-of-industry level and raise funds for activities to address these priorities.

There are currently three Industry Funding Schemes in operation. In addition to the Sheep and Goat IFS, there is a Cattle IFS and a Grains, Seeds and Hay IFS. The three IFSs operate in …


Raising Replacement Ewes For Dairy Sheep Production, Jacob Hadfield, Allen Young Apr 2019

Raising Replacement Ewes For Dairy Sheep Production, Jacob Hadfield, Allen Young

All Current Publications

This fact sheet explains how producers who are seeking more milk production yield, along with more economic value from their replacements can do these three different ways: a) manage replacement rate; b) improve nutrition; and c) optimize reproduction.