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Snyman M.A.,EC Development
South African Journal of Animal Sciences | Year: 2010

The effect of doe age, body weight and different management systems, as practiced in various Angora goat studs, on reproductive performance of does was investigated. The data used were collected from 2000 to 2004 on 12 Angora goat studs kept under different management systems. The data set analysed for this study contained data of 6271 does, each with a varying number of kidding opportunities. This amounted to 14644 doe records where each record included body weight before mating, body weight at scanning (ultrasound scanning for pregnancy diagnosis) and all reproductive performance data. There was a wide range pertaining to reproductive performance among the various studs. Apart from a high kid mortality rate, which is regarded by breeders as the most important factor contributing to low weaning percentages, nearly 20% of the does did not conceive or lost their foetuses before birth. Body weight of does before mating ranged from 13.0kg to 59.6kg (average= 34.6kg) among animals, while body weight at scanning ranged from 18.0kg to 67.0kg (average= 38.6kg). All reproductive parameters recorded had a typical inverted U-shaped relationship with age of dam, where the 2- and 3-year-old does and does older than 9 years of age fared significantly worse than the 4- to 9-year-old does. Management system had a significant influence on reproductive performance of does in the different studs. Higher reproductive rates were recorded under those management systems where additional or supplementary feeding at various stages of the reproductive cycle were supplied. Body weights before mating and at scanning had significant positive relationships with reproduction. For every kilogram increase in body weight before mating, 0.0237 and 0.0218 more kids will be born and weaned, respectively. Body weights before mating of young does that were kept on pastures until 18 months of age were higher than those of maiden does in the other management systems, resulting in higher reproductive rates. Number of kids scanned, born and weaned per maiden doe at first kidding increased with an increase in body weight at first mating. From the results it is evident that body weight, age of the doe and management system all have a significant effect on the reproduction of Angora goats. © South African Society for Animal Science.

Weihs M.,EC Development | Meyer-Weitz A.,University of KwaZulu - Natal
Sahara J | Year: 2014

Despite South African mid-sized companies' efforts to offer HIV counselling and testing (HCT) in the workplace, companies report relatively poor uptake rates. An urgent need for a range of different interventions aimed at increasing participation in workplace HCT has been identified. The aim of this study was to explore qualitatively the influence of a lottery incentive system (LIS) as an intervention to influence shop-floor workers' workplace HIV testing behaviour. A qualitative study was conducted among 17 shop-floor workers via convenience sampling in two mid-sized South African automotive manufacturing companies in which an LIS for HCT was implemented. The in-depth interviews employed a semi-structured interview schedule and thematic analysis was used to analyse the data. The interviews revealed that the LIS created excitement in the companies and renewed employees' personal interest in HCT. The excitement facilitated social interactions that resulted in a strong group cohesion pertaining to HCT that mitigated the burden of HIV stigma in the workplace. Open discussions allowed for the development of supportive social group pressure to seek HCT as a collective in anticipation of a reward. Lotteries were perceived as a supportive and innovative company approach to workplace HCT. The study identified important aspects for consideration by companies when using an LIS to enhance workplace HIV testing. The significance of inter- and intra-player dialogue in activating supportive social norms for HIV testing in collectivist African contexts was highlighted. © 2014 The Author(s). Published by Taylor & Francis.

Snyman M.A.,EC Development
South African Journal of Animal Sciences | Year: 2012

The data used for this study consisted of 27 485 kid records, the progeny of 599 sires and 10 077 dams, and were collected on the 2000- to 2009-born kids of 11 Angora goat studs. Variance and covariance components and ratios pertaining to direct additive genetic variation, maternal additive genetic variation, maternal permanent environmental variation, and the relationship between direct and maternal effects for birth weight (BW; kg), weaning weight (WW; kg) and body weight at 8, 12 and 16 months (W8, W12 and W16; kg) were estimated with the ASReml program. Direct additive heritability estimates of 0.22, 0.20, 0.12, 0.34 and 0.58 were obtained for BW, WW, W8, W12 and W16, respectively. Maternal heritabilities were 0.10, 0.09, 0.03 and 0.06 for BW, WW, W8 and W12, respectively, while maternal environmental effects of 0.13, 0.11, 0.06 and 0.04 were estimated for the latter traits, respectively. An unfavourable correlation of -0.38 was obtained between direct and maternal genetic effects for BW. Low to medium positive direct genetic correlations were estimated between birth weight and body weights recorded at a later stage in life. High positive direct genetic correlations were estimated among WW, W8, W12 and W16. The maternal genetic correlations obtained between birth weight and the other body weights were medium to high. Phenotypic correlations among the traits ranged from low to high. Genetic trends of body weight at different ages indicate that although not many breeders use objective measurement as a selection tool, body weight increased slightly in the 11 studs over the 10-year study period. Since reproduction and body weight should be included in a selection programme for Angora goats, the relationship between the direct and maternal additive effects should be clarified. The importance of a sufficiently structured and related pedigree, especially on the part of the dams and maternal grand dams, has been highlighted in this study. As this is one of the constraints of this data set, data collection in the Angora goat industry should continue until a suitably structured data set has been built up that could be used to estimate multi-trait breeding values for the industry.

Snyman M.A.,EC Development
South African Journal of Animal Sciences | Year: 2010

The data used for this study were collected in 12 different Angora goat studs from 2000 to 2004. Data collected on 17534 kids born alive in the different studs were included in the analyses. Average pre-weaning mortality rate was 11.5% and ranged from 8.6% to 16.5% (of the 17534 kids born alive, 2018 kids died between birth and weaning at four months of age). Mortality rate in male kids was higher than that recorded for female kids (11.9% vs. 11.1%). When comparing the management systems followed from mating up until weaning in the different studs with the corresponding pre-weaning mortality rates, it is obvious that there was no discernible trend. Of the 2018 deaths recorded, the probable cause for only 601 (29.8%) deaths was known. The most important problems were predators, small, unthrifty kids who needed help with suckling, does having little or no milk and does abandoning their kids. When combining the latter three causes with udder problems (3.5%), 35.7% of pre-weaning mortalities was due to these causes. Birth weight and sex of the kid had a significant influence on pre-weaning mortality rate. Single-born kids had the lowest mortality rate (10%), followed by twin-born (13%) and triplet-born (22%) kids. Despite large differences in mortality rate recorded between sires within flocks, a heritability of 0.04± 0.01 was estimated for pre-weaning mortality rate. This low overall heritability could be attributed to the fact that causes of mortality differed considerably among kids and many of these causes may have no genetic background. © South African Society for Animal Science.

Visser C.,University of Pretoria | Van Marle-Koster E.,University of Pretoria | Snyman M.A.,EC Development | Bovenhuis H.,Wageningen University | Crooijmans R.P.M.A.,Wageningen University
Small Ruminant Research | Year: 2013

This study aimed to identify chromosomal regions associated with genetic variation in pre-weaning growth traits in Angora goats. A genome-wide scan was performed by genotyping 1042 offspring from 12 half-sib families using 88 microsatellite caprine markers covering 1368cM. Phenotypes were recorded at birth (BW) and weaning (WW) and analysed using GridQTL software. A total of six putative QTL were detected on six different chromosomes, all at chromosome-wide significance level. Four QTL were identified for BW on CHI 4, 8, 17 and 27 and two QTL for WW on CHI 16 and 19. QTL effects ranged from -0.32 to 0.25 in units of residual standard deviation in different families. Some of these QTL correspond to chromosomes where QTL associated with growth have been identified in other species. These chromosomal segments hold potential to influence weight gain in young goats. © 2012 Elsevier B.V.

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