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A farmer participatory approach was used to identify trait preferences and breeding practices for Afar goat population in Aba'ala district, Afar region, Ethiopia. A rapid field survey followed by purposive sampling was used to identify research sites and 90 households representing agro-pastoral and pastoral production systems were selected purposively. Data were obtained from individual interview, own-flock ranking experiment, and secondary sources. Data management and analysis was done using MS-Excel and SPSS statistical software. The current findings show that goats were primarily kept for milk production (I = 0.33) followed by income generation (I = 0.27) and meat production (I = 0.17) in both production systems. Higher goat flock size per household was observed in the pastoral areas (94.62 ± 30.21goats) as compared to the agro-pastoral (55.56 ± 20.06) (p < 0.05). Coat color, appearance (conformation and body size), and pedigree (dam history for milk) are the top-ranked attributes for selecting breeding buck with index value of 0.28, 0.23, and 19, respectively. Milk yield, coat color, and appearance were also used for selecting breeding does with index values of 0.24, 0.20, and 0.17, respectively. Selection of breeding female is hardly practiced since all females are used for replacement, but breeding buck selection is done in a very young age primarily based on their coat color. The results obtained in this study could be used as input to design genetic improvement programs for goats in Aba'ala. Interventions are needed in expanding veterinary service, improved animal husbandry practices, and selective breeding to enhance the productivity of the goat populations.

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This study assessed genetic variation, heritability estimates, and genetic correlations for concentrations of plasma β-hydroxybutyrate (BHBA), milk BHBA, and milk acetone in early lactation to investigate differences between cows in susceptibility to hyperketonemia and possibilities to use test-day milk ketone bodies for genetic improvement. Blood and test-day milk samples were collected on randomly selected dairy farms in the Netherlands from cows of various parities between 5 and 60 d in milk. Plasma samples were analyzed for BHBA (reference test for hyperketonemia) and test-day milk samples were analyzed for BHBA and acetone using Fourier-transform infrared spectroscopy. The final data set consisted of plasma BHBA concentrations of 1,615 cows from 122 herds. Milk BHBA and milk acetone concentrations were determined for 1,565 cows. Genetic variation, heritability, and proportion of phenotypic variation attributable to the herd were estimated using an animal model with fixed effects for parity and season, a covariate for days in milk, and random effects for herd, animal, and error. Genetic correlations for plasma BHBA, milk BHBA, and milk acetone were estimated using bivariate analyses. The heritability estimate for plasma BHBA concentrations in early lactation was 0.17, whereas heritability estimates for milk BHBA and milk acetone were 0.16 and 0.10, respectively. This indicates that selective breeding may contribute to a lower incidence of hyperketonemia in early lactation. For the 3 traits, the proportion of variance attributable to herd was larger than the additive genetic variance, underlining the importance of on-farm feeding and management in the etiology of hyperketonemia in fresh cows. Prevention strategies for hyperketonemia can, therefore, include both feeding and management strategies at dairy farms (short-term) and genetic improvement through breeding programs (long-term). Genetic correlations between concentrations of plasma BHBA and milk BHBA (0.52) or milk acetone (0.52) were moderate. As milk ketone bodies can be routinely analyzed at test days, this may provide a practical alternative for breeding programs aimed at reducing hyperketonemia in early lactation., (Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)