Identifying breeding objectives of smallholders/pastoralists and optimizing community-based breeding programs for adapted sheep breeds in Ethiopia

The aim of this thesis was to identify breeding objectives of smallholder and pastoral sheep keepers in Ethiopia (Afar, Bonga, Horro and Menz areas) and to design appropriate community-based breeding plans for genetic improvement of four indigenous sheep breeds. Information on genetics of adaptation in farm animals was reviewed. Two live animals ranking experiments approaches, own-flock and groupanimal ranking, were used to identify sheep breeding objectives. In own-flock ranking, owners paid more attention to production and reproduction performances and behavioral traits (e.g. milk yield, temperament, lamb growth, mothering ability, body size, lambing interval). In group-animal ranking, observable attributes like coat color, tail type, ear size, body size, etc. recurred. Afar (pastoral) and Menz (sheepbarley) sheep breeders, coping with more challenging production environments, considered more attributes compared to the two crop-livestock systems (Bonga and Horro). Four scenarios of ram selection and ram use were compared via deterministic simulation of breeding plans for community-based sheep breeding programs considering the top three most important traits identified. The review work revealed the need to identify the most appropriate and adapted genotypes capable of coping with environmental challenges posed by the production systems or, wherever possible, adapt the environments to the requirements of the animals. In conclusion, both own-flock and group-animal ranking experiments can serve as tools in objective traits identification in production systems without recording practices. Strong selection and short use of rams for breeding were the preferred options. Expected genetic gains are satisfactory but rely on continuous recording

Simulation of Alternative Plans for Community Based Goat Breeding Program in Arid, Semi-Arid and Mixed Production Systems in Ethiopia

On station small ruminant researches in Ethiopia were ineffective due to various factors. As alternative, community based breeding program (CBBP) has emerged. In the current CBBPs, sire side selection only (SN1) is practiced. The objective of the present work was to compare SN1 by simulating alternative breeding scenarios for Abergelle (AB), Centeral Highland (CH) and Woyto-Guji (WG) goat breeds in Ethiopia. Three scenarios including selection on dam side (SN2) in addition to SN1, application of genomic selection (SN3) onto SN1 and use of sires from SN1 for mating in additional flocks (SN4) were simulated and compared with SN1 based on the predicted annual genetic gain (PAGG) and discounted profits. The breeding objective traits or selection criteria were six month weight (6mw, kg) for all breeds, average daily milk yield (ADM, kg) and survival to six month of age (SURV) for AB, litter size at birth (LSB) for CH and WG, litter size at weaning (LSW) for CH and kidding interval (KI, days) for WG. ZPLAN+ software was used for the simulation. The PAGG for 6mw (kg) ranged from 0.087 (SN4) to 0.25 (SN3) for AB where it ranged from 0.47 (SN4) to 0.97 (SN3) for ADM (kg) for same breed. PAGG in 6mw (kg) ranging from 0.13 (SN4) to 0.47 (SN3) and from 0.20 (SN4) to 0.31 (SN3) for CH Gonder and Ambo sites, respectively were simulated whereas this parameter ranged from 0.10 (SN4) to 0.27 (SN3) for WG. The alternative breeding scenarios to SN1 resulted in better PAGGs, especially for 6mw in three of the goat breeds and for ADM in AB. Based on the PAGGs and profitability, we recommend SN2 over SN1. However, SN4 could also be applied, compared to SN1, in view of suitability of addressing emerging demands

Breeding objectives for Red Maasai and Dorper sheep in Kenya—A participatory approach

The Red Maasai sheep breed is under threat due to indiscriminate crossbreeding and strategies are needed to conserve and improve the breed. The aim of this study was to understand farmers’ preferences for important traits of flocks of Red Maasai, Dorper and crosses in two different areas, Amboseli and Isinya, in Kenya. Farmers identified three ewes that represented the best, average, and poorest within its breed group of each farm and gave reasons for their ranking. The most important traits were body size and growth rate and thereafter milk yield. The Red Maasai was preferred for its better reproduction and tolerance against diseases and drought. In the harshest area, Amboseli, all breed groups had about the same body weight, whereas in Isinya, where conditions are better and farmers are more market oriented, Dorper and crosses had superior weights

Haplotype Affinities Resolve a Major Component of Goat (Capra hircus) MtDNA D-Loop Diversity and Reveal Specific Features of the Sardinian Stock

Goat mtDNA haplogroup A is a poorly resolved lineage absorbing most of the overall diversity and is found in locations as distant as Eastern Asia and Southern Africa. Its phylogenetic dissection would cast light on an important portion of the spread of goat breeding. The aims of this work were 1) to provide an operational definition of meaningful mtDNA units within haplogroup A, 2) to investigate the mechanisms underlying the maintenance of diversity by considering the modes of selection operated by breeders and 3) to identify the peculiarities of Sardinian mtDNA types. We sequenced the mtDNA D-loop in a large sample of animals (1,591) which represents a non-trivial quota of the entire goat population of Sardinia. We found that Sardinia mirrors a large quota of mtDNA diversity of Western Eurasia in the number of variable sites, their mutational pattern and allele frequency. By using Bayesian analysis, a distance-based tree and a network analysis, we recognized demographically coherent groups of sequences identified by particular subsets of the variable positions. The results showed that this assignment system could be reproduced in other studies, capturing the greatest part of haplotype diversity

Effect of feed restriction on compensatory growth of Arsi (Bos indicus) bulls

A study was conducted to evaluate the efficiency of compensatory feeding. Twenty-five Arsi bulls (32±4 months) were blocked by weight and randomly allocated to the following feed restriction treatments: ad libitum feeding for the entire period (control), maintenance feeding level (maintenance), 15% body weight loss (-15%), 20% body weight loss (-20%) and 25% body weight loss (-25%). A 91-day period of feed restriction was followed by a 105-day re-alimentation period. No treatment effects was observed on average daily gain (ADG) or feed conversion efficiency (FCE) during the compensatory period, both between control and maintenance feeding levels, and within the restricted treatment groups. Recovery index differed (P0.05) between control and maintenance groups as well as among restricted treatments. Although statistically not significant, compensatory gains, FCE, and lean meat yield for treatments -15, -20 and -25% had increasing tendencies with increasing levels of feed restriction. Therefore, Arsi bulls need longer than 105 days of compensatory feeding for complete recovery of LW losses caused by different levels of restriction in a period of 91 days. The appropriate time of feeding and change in the energy density of the diet by manipulating the roughage and concentrate ratios for complete compensation following different levels of retarded growth along with cost–benefit relationship requires further investigation

Efficiency of compensatory growth of Borana bulls (Bos indicus) following different levels of feed restriction

To study the efficiency of compensatory growth following different levels of feed restriction, 25 Borana bulls were blocked by weight and randomly allocated to five dietary treatments of ad libitum feeding for the entire period (control), maintenance feeding for 91 days (maintenance), 15 per cent weight loss in 91 days (-15%), 20 per cent weight loss in 91 days (-20%) and 25 per cent weight loss in 91 days (-25%) followed by 105 days of ad libitum (compensatory) feeding. The feed restriction imposed for treatments - 15 per cent, -20per cent and -25per cent during the initial period resulted in weight losses of -15 per cent, -19 per cent and -23 per cent, respectively. There was no significant (P>0.05) difference among treatments on feed intake during compensatory feeding period. Daily gain (ADG) for the restricted animals was directly proportional to the level of feed restriction. There was also significant (P<0.05) treatment effect on dressing percentage and proportion of fat in carcass. Animals subjected to weight losses of -15 per cent, -20 per cent and -25 per cent had lower yield of these carcass characteristics than the control and maintenance treatment. This study revealed that Borana bulls may not achieve complete compensation in 105 days of compensatory feeding, after 91 days of feed restriction below their daily maintenance requirement

Comparison of the efficiency of compensatory growth of Borana and Arsi cattle in Ethiopia

The efficiency of compensatory growth of 50 Bos indicus (25 Arsi & 25 Borana) bulls with age 28-36 months following different levels of feed restriction for 90 days was studied. The bulls were blocked by weight and randomly assigned to five dietary treatments: ad libitum feeding for the entire period (A), maintenance requirement for 90 days followed by ad libitum feeding for 104 days B), 15% weight loss in 90 days followed by ad libitum feeding for 104 days (C), 20% weight loss in 90 days followed by ad libitum feeding for 104 days (D) and 25% weight loss in 90 days followed by ad libitum feeding for 104 days (E). The feed restriction imposed for treatments C, D and E during the initial period resulted in weight losses of 16%, 20% & 23% respectively. Both daily dry matter intake (DMI) and metabolizable energy intake (MEI) during the restriction period declined with increasing levels of feed restriction. Consequently average daily weight gain (ADG) and metabolizable energy intake (MJ/day). During compensatory feeding period were significantly different among treatments (P0.05) different among treatments, but significantly (P<0.05) different between breeds. Arsi bulls had higher (59%) recovery index than Borana bulls (30%). Even though the overall TDMI and MEI during compensatory feeding were increased by four folds than during the restriction period, animals under treatments B, C, D and E could not attain complete compensation within 104 days of compensatory feeding. But Arrsi bulls managed under maintenance feeding level recovered 96% of their weight loss after 104 days of compensatory feeding as compared to Borana bulls (25%) managed similarly. The overall carcass weight indicated declining trend with increasing levels of feed restriction. The results of this study indicated that responses to compensatory feeding are influenced by either severity of under nutrition, breed type of cattle or duration of compensatory fending. The optimum time and cost-benefit relationships at which complete recovery can be attained after a period of feed restriction require further investigation