Returns on investment in sheep and goat breeding in South Africa

Schoeman, S.J.; Cloete, S.W.P.; Olivier, J.J.

doi:10.1016/j.livsci.2010.02.012

Cited by 36 publications

(42 citation statements)

References 31 publications

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“…The registration system for all seed stock animals in South Africa dates back to 1904 (Schoeman et al, 2010) and made provision for storage of pedigree information and official performance recording. A pilot study for animal recording in Angora goats was only implemented in 1983, with the approval of the Angora Stud Breeders' Society (Delport and Erasmus, 1984).…”

Section: Selection Programsmentioning

confidence: 99%

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Strategies for the genetic improvement of South African Angora goats

Visser

Marle-Köster

2014

Small Ruminant Research

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Selection of Angora goats over the past decades has focused on traits related to fitness, body weight and fiber production. Research for genetic improvement of the Angora has been based on quantitative selection and more recently molecular technology has been applied. Although considerable progress has been made at increasing fine mohair production, the inability of Angora goats to survive sub-optimum conditions has become a concern. Selection emphasis on fibre production resulted in unthrifty animals and the South African (SA) Angora industry is still hampered by the loss of young goats. DNA marker information assists conventional selection by increasing selection accuracy, improving the rate of genetic improvement and leading to a better understanding of the physiological background of traits. The genetic diversity of the SA Angora goat breed was estimated and an improved linkage map was recently developed. The extensive production systems in South Africa pose a challenge for pedigree integrity, and a microsatellite panel was constructed for parentage verification. Selection for quantitative trait loci (QTL) will lead to increased genetic progress and offers the opportunity to improve understanding of and exploit phenotypic variation.Putative QTL associated with fleece and growth traits have been identified in the South African Angora goat population. The current goat SNP chip does not include any fibre-producing goat breed, and this chip is currently being verified in the SA Angora goat population, in conjunction with the sequencing of certain keratin genes.

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Section: Selection Programsmentioning

confidence: 99%

“…A fine-hair resource flock was established in 1988 at the Jansenville Experimental Station in the Eastern Cape Province with the aim of breeding fine-hair producing Angora goats, without sacrificing body weight (Snyman, 2002;Schoeman et al, 2010). Two lines were maintained, a control herd and a fine hair herd.…”

Section: Research Flockmentioning

confidence: 99%

Strategies for the genetic improvement of South African Angora goats

Visser

Marle-Köster

2014

Small Ruminant Research

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“…The SA Merino samples were from resource flocks maintained at Cradock (n = 50) and Grootfontein (n = 50) in the Eastern Cape (Schoeman et al, 2010). Genotyping was done with the OvineSNP50 chip (Illumina) at GeneSeek Inc. (Lincoln, Nebr, USA) from samples applied to blood cards.…”

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confidence: 99%

Evaluation of the OvineSNP50 chip for use in four South African sheep breeds

et al. 2016

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Relatively rapid and cost-effective genotyping using the OvineSNP50 chip holds great promise for the South African sheep industry and research partners. However, SNP ascertainment bias may influence inferences from the genotyping results of South African sheep breeds. Therefore, samples from Dorper, Namaqua Afrikaner (NA), South African Merino (SA Merino) and South African Mutton Merino (SAMM) were genotyped to determine the utility of the OvineSNP50 chip for these important South African sheep breeds. After quality control measures had been implemented, 85 SA Merino, 20 Dorper, 20 NA and 19 SAMM samples remained, with an average call rate of 99.72%. A total of 49 517 (91.30%) SNPs on the chip met quality control measures and were included in downstream analyses. The NA had the fewest polymorphic loci, 69.20%, while the SAMM, Dorper and SA Merino had between 81.16% and 86.85% polymorphic loci. Most loci of the SA Merino, Dorper and SAMM had a MAF greater than or equal to 0.3. In contrast, the NA exhibited a large number of rare alleles (MAF < 0.1) and a uniform distribution of other loci across the MAF range (0.1 < MAF ≤ 0.5). The NA exhibited the least genetic diversity and had the greatest inbreeding coefficient among the four breeds. The results of the Dorper, SA Merino, and SAMM compare favourably with those of international breeds and thus demonstrate the utility of the OvineSNP50 chip for these breeds. Effects of SNP ascertainment bias, however, could be seen in the number of non-polymorphic loci and MAF distribution of the three commercial breeds in comparison with those of the NA. The implementation of methods to reduce the effect of SNP ascertainment bias and to ensure unbiased interpretation of genotype results should therefore be considered for future studies using OvineSNP50 chip genotype results.

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“…Robustness encompass a group of traits enabling animals to adapt and includes several reproduction and survival traits such as disease and parasite resistance, heat tolerance and drought tolerance [50]. Reproduction and survival traits in livestock are known to be lowly heritable and in spite of this, genetic progress has been possible for over 20 years of selection in South African sheep flocks [7]. This indicates the possibility of using adaptive genetic variation to improve robustness traits in South African sheep flocks.…”

Section: Genetic Variability For Adaptability and Robustnessmentioning

confidence: 99%

“…Another option to improve production performance of indigenous breeds would be increase selection for desired traits using genomic selection. Selection for improved robustness or production traits will reduce genetic diversity in a population, however the reduction in diversity will be gradually over a number of generations [7]. This is due to the additive effect of genes using traditional selection methods, where the effect will be cumulative.…”

Section: Indigenous Breeds In Smallholder Sheep Farming Systemsmentioning

confidence: 99%

Genetic Traits of Relevance to Sustainability of Smallholder Sheep Farming Systems in South Africa

et al. 2017

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Sustainable livestock production is important to ensure continuous availability of resources for future generations. Most smallholder livestock farming systems in developing countries have been perceived to be environmentally, socially and economically unsustainable. Farming with livestock that is robust and adaptable to harsh environments is important in developing countries especially in semi-arid and arid environments. This review discusses the different sheep farming systems employed by smallholder farmers and associated sustainability problems facing them. The review also gives an overview of sustainability indicators and limitations to the sustainability for the different smallholder sheep production systems in South Africa. It is argued that genetic diversity is important for sustainability and needs to be maintained in sheep for sustainable production and reproduction performance. The application of traditional breeding and genomics to ensure sustainable production is explored. Animal breeding approaches, specifically genomics can be applied to improve areas of environmental sustainability of smallholder sheep farming systems but must be targeted to the specific production environments, challenges, and opportunities of smallholder production. The genetic traits important for sustainability, the role of genomics in improving these traits and linking these genetic traits to different farming systems in South Africa are discussed.

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Returns on investment in sheep and goat breeding in South Africa

Cited by 36 publications

References 31 publications

Strategies for the genetic improvement of South African Angora goats

Strategies for the genetic improvement of South African Angora goats

Evaluation of the OvineSNP50 chip for use in four South African sheep breeds

Genetic Traits of Relevance to Sustainability of Smallholder Sheep Farming Systems in South Africa

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