Factors affecting the length of productive life in U.S. Katahdin ewes.

The length of ewe productive life (LPL), defined as the number of days between the first and last lambing, is a key indicator of ewe longevity and is directly related to the sustainability of the sheep industry. Therefore, the primary objective of this study was to investigate systematic effects influencing LPL in Katahdin sheep. The LPL of 10,474 Katahdin ewes (69.

Adding gastrointestinal parasite resistance to the breeding objective in hair sheep: initial steps.

The U.S. Maternal Hair Index was designed by the National Sheep Improvement Program (NSIP) to increase total weight of lamb weaned per ewe lambing (TW).

Genetic diversity of United States Rambouillet, Katahdin and Dorper sheep.

Background: Managing genetic diversity is critically important for maintaining species fitness. Excessive homozygosity caused by the loss of genetic diversity can have detrimental effects on the reproduction and production performance of a breed. Analysis of genetic diversity can facilitate the identification of signatures of selection which may contribute to the specific characteristics regarding the health, production and physical appearance of a breed or population.

Genotype by environment interaction and heteroscedasticity influence the expression of parasite resistance in Katahdin sheep.

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.

Wild bees respond differently to sampling traps with vanes of different colors and light reflectivity in a livestock pasture ecosystem.

Wild bees are important pollinators and monitoring their abundance and diversity is necessary to develop conservation protocols. It is imperative to understand differences in sampling efficiency among different trap types to help guide monitoring efforts. This study used a new vane trap design to collect bees in a livestock pasture ecosystem and examined the impact of six different vane colors on wild bee sampling.

Single Nucleotide Polymorphism Effects on Lamb Fecal Egg Count Estimated Breeding Values in Progeny-Tested Katahdin Sires.

Estimated breeding values (EBV) for fecal egg counts (FEC) at 42-90 days of age (WFEC) and 91-150 days of age (PFEC) for 84 progeny-tested Katahdin sires were used to identify associations of deregressed EBV with single-nucleotide polymorphisms (SNP) using 388,000 SNP with minor-allele frequencies ≥0.10 on an Illumina high-density ovine array. Associations between markers and FEC EBV were initially quantified by single-SNP linear regression.

Soil microbial diversity in organic and non-organic pasture systems.

Understanding the effects of organic pasture management on the soil microbiome is important for sustainable forage production since soil microbiome diversity contributes to improved nutrient cycling, soil structure, plant growth, and environmental resiliency; however, the soil microbiome response to pasture management is largely unknown. This study assessed the soil microbial diversity, richness, and community structure following 10 years of pasture management (organic or non-organic) of the V4 region of the 16S rRNA using the Illumina MiSeq platform. Soil samples were collected from 0-15 cm in July and August from 2017-2018 and soil nutrient properties (nutrients, carbon, nitrogen, and pH) quantified and correlated with soil microbial diversity.

Endophyte-Infected Tall Fescue Affects Rumen Microbiota in Grazing Ewes at Gestation and Lactation.

Tall fescue () is a cool-season perennial grass that is widely used as a forage for many livestock species including sheep. An endophyte ( in tall fescue produces ergot alkaloids that enhance plant survival but produce toxicosis in animals. The objective of this study was to investigate the rumen microbiota from gestation and lactation in ewes grazing tall fescue pastures with high (HA) or moderate (MA) levels of endophyte infection, and their relationship with serum parameters.

Quebracho tannins aid in the control of Eimeria spp. and gastrointestinal nematodes in lambs and goat kids.

The objective was to examine the effects of supplementary quebracho on control of coccidiosis and gastrointestinal nematodes in lambs and kids. In Exp. 1, naturally infected lambs weaned (87.

Sustainable Approaches to Parasite Control in Ruminant Livestock.

It is increasingly difficult to manage and control gastrointestinal nematode parasites in pasture-based ruminant livestock operations because of the high prevalence of anthelmintic resistance. Anthelmintics should be combined with alternative forms of control. Sustainable tools include copper oxide wire particles and condensed tannin-rich plants, which target primarily Haemonchus contortus in small ruminants.

Genetic parameters for ewe reproductive performance and peri-parturient fecal egg counts and their genetic relationships with lamb body weights and fecal egg counts in Katahdin sheep.

This study estimated genetic parameters for ewe reproductive traits [number of lambs born (NLB) and weaned (NLW) per ewe lambing] and fecal egg counts (FEC) during the peri-parturient rise (PPR) for use in genetic evaluation of Katahdin sheep. Data included NLB and NLW for 23,060 lambings by 9,295 Katahdin ewes, 1,230 PPR at lambing (PPR0) for 750 ewes, 1,070 PPR at approximately 30 d postpartum (PPR30) for 611 ewes, BW at birth, weaning, and (or) post-weaning for 12,869 lambs, and FEC at weaning and (or) post-weaning for 4,676 lambs. Direct additive, permanent environmental, and residual (co)variances were estimated in univariate and bivariate animal models.

Whole genome structural analysis of Caribbean hair sheep reveals quantitative link to West African ancestry.

Hair sheep of Caribbean origin have become an important part of the U.S. sheep industry.

Experiences with integrated concepts for the control of Haemonchus contortus in sheep and goats in the United States.

The generally warm, moist environmental conditions in the southern United States (U.S.) are ideal for survival and growth of the egg and larval stages of Haemonchus contortus and other gastrointestinal nematodes (GIN) of sheep and goats.

Prevalence of anthelmintic resistance on sheep and goat farms in the southeastern United States.

Objective: To determine prevalence of anthelmintic resistance on sheep and goat farms in the southeastern United States.

Design: Cross-sectional study.

Animals: Sheep and goats from 46 farms in 8 southern states, Puerto Rico, and St Croix in the US Virgin Islands.

Recruitment strategies for studying dementia in later life among diverse cultural groups.

This article provides conceptual and theoretical guidance on approaches to enhance recruiting and retaining diverse populations in dementia research by using a sociocultural perspective and constructivist approach. Informed by this conceptual and theoretical guidance, the article also discusses some of the major barriers to recruitment with ideas on how to address these barriers. Further discussion is provided on building community relations and capacity, and strategies to increase the level of participation in dementia care research.