Impact of young ewe fertility rate on risk and genetic gain in sheep-breeding programs using genomic selection

Newton, J. E.; Brown, D. J.; Dominik, Sonja; Werf, J. H. J. van der

doi:10.1071/an15321

Cited by 6 publications

(5 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Reproductive success is an important determinant of profitability for commercial sheep production enterprises focused on lamb meat production (Amer et al, 1999;Newton et al, 2017), and understanding factors that influence establishment of pregnancy in the ewe is key to improving flock reproductive performance. Although numerous studies have shown the impact of factors such as age and nutrition on ewe reproductive performance (Gaskins et al, 2005;Pettigrew et al, 2019), there is a paucity of information regarding if and how the microbiota of the ewe reproductive tract may contribute to pregnancy outcome.…”

Section: Introductionmentioning

confidence: 99%

Ewe Vaginal Microbiota: Associations With Pregnancy Outcome and Changes During Gestation

et al. 2021

View full text Add to dashboard Cite

Reproductive performance is paramount to the success of livestock production enterprises focused on lamb meat production. Reproductive success is influenced by various factors, possibly including the reproductive tract microbial communities present at the time of copulation and throughout pregnancy. There are few publications that identify the vaginal microbial communities of livestock, and even fewer exist for sheep. To compare ewe vaginal microbial communities, vaginal swabs were taken from 67 Hampshire and Hampshire X Suffolk crossbred ewes from the Iowa State University sheep farm at a pre-breeding time point (S1) and after pregnancy testing (S2). Animals that were determined pregnant were sampled again within a few days of expected parturition (S3). DNA was extracted from these swabs, and 16S rRNA gene Illumina MiSeq amplicon sequencing was conducted to fingerprint the bacterial communities found within this system. Pre-breeding time point samples showed no differences in community structure between animals later found to be pregnant or non-pregnant, but significant changes were detected in species richness (Chao; P < 0.001) and species diversity (Shannon; P < 0.001) at the second sampling time point. A higher microbial diversity within the S2 time point samples may suggest a more stable environment driven by pregnancy, as this increased diversity is maintained in pregnant animals from the S2 to the S3 time point. Additionally, several bacterial phylotypes, such as Mannheimia, Oscillospiraceae-like OTUs and Alistipes, were more abundant at either the S1 or S2 time points in animals that established pregnancy, suggesting a beneficial effect on pregnancy outcome. This study identifies changes within the microbial communities of the ewe vagina before and during gestation and offers inferences on how these changes may impact pregnancy outcome. Information presented herein offers new knowledge about sheep vaginal microbial communities and serves as a starting point to help guide researchers to improve sheep reproductive performance in the future.

show abstract

Section: Introductionmentioning

confidence: 99%

Ewe Vaginal Microbiota: Associations With Pregnancy Outcome and Changes During Gestation

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Granleese (Granleese et al, 2015) simulated GS in sheep under optimal contribution selection, and found that the MOET and MOET+JIVET programs increased the genetic gain by 38%-76% and 51%-81%, respectively. Newton (Newton et al, 2017) used a genomic information-based simulation to model the impact of different age structures of sheep populations on reproductive performance in Australian sheep. The results showed that the availability of ram and ewe age as well as male genomic information significantly affected the predicted genetic gain, and genetic progress was unlikely to be adversely affected at fertility rates of 10% or more.…”

Section: Research Progress Of Gs In Reproductive Traits Of Sheep and ...mentioning

confidence: 99%

Progress and Application of Genomic Selection in Sheep and Goat

Zhang,

Duan,

et al. 2024

Preprint

View full text Add to dashboard Cite

The advancement of sequencing technology and molecular breeding methods have provided technical support and assurance for accurate breeding. Genomic Selection (GS) utilizes genomic information to improve livestock breeding and, it is more accurate and more efficient than traditional selection methods. GS has been widely applied in domestic animals breeding, especially in cattle. However, there is still limited study on the application and research of GS in sheep and goat. In this paper, we outlined the principle, analysis methods, the influential factors of GS, and elaborated on the research progress, challenges, and prospects of applying GS in sheep and goat breeding. Through the review of these aspects this paper is expected to provide valuable references for the implementation of GS in the field of sheep and goat breeding.

show abstract

“…This has substantial impacts in reducing the emission intensity of milk (Christie et al 2016) and of lamb, as well as increasing profitability (Alcock et al 2015;Tocker et al 2020). It also increases the speed of genetic gain (Newton et al 2017). Timing of onset of puberty is determined by liveweight, rather than the rate or timing of liveweight gain, and so is subject to post-weaning nutritional control (Bruinje et al 2021).…”

Section: Age At First Joiningmentioning

confidence: 99%

A regional-scale assessment of nutritional-system strategies for abatement of enteric methane from grazing livestock

2023

View full text Add to dashboard Cite

Progress towards methane (CH4) mitigation for the red meat, milk and wool sectors in Australia and reduced CH4 emissions intensity (g CH4/kg animal product, typically milk or liveweight gain) involves not only reduced net emissions but also improved productive efficiency. Although nutritional additives have potential to reduce CH4 production rate of livestock (g CH4/head.day), systemic improvement of the nutrition of grazing breeding females, the largest source of CH4 emissions in Australian agriculture, will also be required to reduce emissions intensity. Systemic changes that increase productive efficiency for producers are part of the economic and environmental ‘win–win’ of reducing emissions intensity, and so offer good potential for adoption by industry. For sheep and cattle breeding enterprises, improved nutrition to achieve a younger age at first joining and increased reproductive rate will reduce the proportion of CH4-emitting, but unproductive, animals in a herd. However, if breeding stock are managed to be more productive (e.g. by superior nutrition leading to greater product/breeder) and more efficient (e.g. greater product per kilogram DMI) the producer is faced with the following management challenge. Should the enterprise increase stock numbers to utilise surplus feed and gain extra product, or reduce stock numbers to maintain previous product output with smaller enterprise net emissions (and emissions intensity), and so make land available for other uses (e.g. tree plantings, conservation zones). The right balance of incentives and price on carbon is necessary to achieve a result whereby total emissions from Australian agriculture are reduced, and so a positive impact on climate change is achieved.

show abstract

Impact of young ewe fertility rate on risk and genetic gain in sheep-breeding programs using genomic selection

Cited by 6 publications

References 21 publications

Ewe Vaginal Microbiota: Associations With Pregnancy Outcome and Changes During Gestation

Ewe Vaginal Microbiota: Associations With Pregnancy Outcome and Changes During Gestation

Progress and Application of Genomic Selection in Sheep and Goat

A regional-scale assessment of nutritional-system strategies for abatement of enteric methane from grazing livestock

Contact Info

Product

Resources

About