Community-based sheep breeding programs generated substantial genetic gains and socioeconomic benefits.

Community-based breeding programs (CBBPs) for small ruminants have been suggested as alternatives to centralised, government-controlled breeding schemes which have been implemented in many developing countries. An innovative methodological framework on how to design, implement and sustain CBBPs was tested in three sites in Ethiopia: Bonga, Horro and Menz. In these CBBPs, the main selection trait identified through participatory approaches was 6-month weight in all three sites. In Horro and Bonga, where resources such as feed and water permitted larger litter sizes, twinning rate was included. Ten-year (2009 to 2018) performance data from the breeding programs were analysed using Average Information Restricted Maximum Likelihood method (AI-REML). Additionally, the socioeconomic impact of CBBPs was assessed. Results indicated that 6-month weight increased over the years in all breeds. In Bonga, the average increase was 0.21 ± 0.018 kg/year, followed by 0.18 ± 0.007 and 0.11 ± 0.003 kg/year in Horro and Menz, respectively. This was quite substantial in an on-farm situation. The birth weight of lambs did not improve over the years in Bonga and Horro sheep but significant increases occurred in Menz. Considering that there was no direct selection on birth weight in the community flock, the increased weights observed in Menz could be due to correlated responses, but this was not the case in Bonga and Horro. The genetic trend for prolificacy over the years in both Bonga and Horro flocks was positive and significant (P < 0.01). This increase in litter size, combined with the increased 6-month body weight, increased income by 20% and farm-level meat consumption from slaughter of one sheep per year to three. The results show that CBBPs are technically feasible, result in measurable genetic gains in performance traits and impact the livelihoods of farmers.

Genetic evaluation of test-day milk yields from smallholder dairy production systems in Kenya using genomic relationships.

Efforts to improve dairy production in smallholder farming systems of East Africa over the past decade have had limited impact because of the lack of records on performance to guide targeted breeding programs. Estimates of genetic parameters in these systems are lacking. Using data generated through a project ("Germplasm for Dairy Development in East Africa") in Kenya and a genomic relationship matrix from genotypic records, we examined the potential impact of different models handling contemporary groups or herd effects on estimates of genetic parameters using a fixed regression model (FRM) for test-day (TD) milk yields, and the covariance structure for TD milk yield at various stages of lactation for animals using a random regression model (RRM). Models in which herd groups were defined using production levels derived from the data fitted the data better than those in which herds were grouped depending on management practices or were random. Lactation curves obtained for animals under different production categories did not display the typical peak yield characteristic of improved dairy systems in developed countries. Heritability estimates for TD milk yields using the FRM varied greatly with the definition of contemporary herd groups, ranging from 0.05 ± 0.03 to 0.27 ± 0.05 (mean ± standard error). The analysis using the RRM fitted the data better than the FRM. The heritability estimates for specific TD yields obtained by the RRM were higher than those obtained by the FRM. Genetic correlations between TD yields were high and positive for measures within short consecutive intervals but decreased as the intervals between TD increased beyond 60 d and became negative with intervals of more than 5 mo. The magnitude of the genetic correlation estimates among TD records indicates that using TD milk records beyond a 60-d interval as repeated measures of the same trait for genetic evaluation of animals on smallholder farms would not be optimal. Although each individual smallholder farmer retains only a few animals, using the genomic relationship between animals to link the large number of farmers operating under specified environments provides a sufficiently large herd-group for which a breeding program could be developed.

Community-based livestock breeding programmes: essentials and examples.

Breeding programmes described as community-based (CBBP) typically relate to low-input systems with farmers having a common interest to improve and share their genetic resources. CBBPs are more frequent with keepers of small ruminants, in particular smallholders of local breeds, than with cattle, pigs or chickens with which farmers may have easier access to alternative programmes. Constraints that limit the adoption of conventional breeding technologies in low-input systems cover a range of organizational and technical aspects. The analysis of 8 CBBPs located in countries of Latin-America, Africa and Asia highlights the importance of bottom-up approaches and involvement of local institutions in the planning and implementation stages. The analysis also reveals a high dependence of these programmes on organizational, technical and financial support. Completely self-sustained CBBPs seem to be difficult to realize. There is a need to implement and document formal socio-economic evaluations of CBBPs to provide governments and other development agencies with the information necessary for creating sustainable CBBPs at larger scales.

Use of SNP genotyping to determine pedigree and breed composition of dairy cattle in Kenya.

High levels of inbreeding in East African dairy cattle are a potential concern because of use of a limited range of imported germplasm coupled with strong selection, especially by disease, and sparse performance recording. To address this, genetic relationships and breed composition in an admixed population of Kenyan dairy cattle were estimated by means of a 50K SNP scan. Genomic DNA from 3 worldwide Holstein and 20 Kenyan bulls, 71 putative cow-calf pairs, 25 cows from a large ranch and 5 other Kenyan animals were genotyped for 37 238 informative SNPs. Sires were predicted and 89% of putative dam-calf relationships were supported by genotype data. Animals were clustered with the HapMap population using Structure software to assess breed composition. Cows from a large ranch primarily clustered with Holsteins, while animals from smaller farms were generally crosses between Holstein and Guernsey. Coefficients of relatedness were estimated and showed evidence of heavy use of one AI bull. We conclude that little native germplasm exists within the genotyped populations and mostly European ancestry remains.

Lambing date and lamb production of spring-mated Rambouillet, Dorset and Finnsheep ewes and their F1 crosses.

The reproductive performance of 255 Rambouillet (R), Dorset (D), Finnsheep (F) and F1 ewes born in 1978-1979 (group I) and 1979-1980 (group II) and managed in a semiconfinement fall/winter lambing system was evaluated through 4 yr of age of all ewes and through 5 yr for a portion of group I ewes. Ewes were with rams from approximately May 1 to late September each year, with a 2-wk break late in July/early August. Traits considered were fertility (ewes lambed/ewes exposed), lambing date, litter size, lamb survivial and 70-d lamb weights. Breeds and crossbred groups differed significantly in lambing date, with DR crossbred ewes earliest and F ewes latest. Repeatabilities for groups I and II were .31 and .22, .24 and .24 and .11 and .07 for lambing date, fertility and litter size, respectively. There was no significant heterosis in lambing date, although DR ewes in both groups I and II were superior to (D + R)/2, by about 1 wk on average. There was significant positive heterosis for fertility and traits of which fertility is a component in FR ewes in group I, but none in group II. The FD ewes showed negative heterosis for litter size, -.23 (P less than .05) for group I and -.09 for group II. The results indicate: F and FD ewes are not well adapted to the Mediterranean climate where this experiment was conducted; there is little, if any, useful heterosis in crosses among these three breeds for lambing date or other reproduction traits and RD and R ewes are most suitable of the groups tested, while late onset of the breeding season limits the usefulness of even 50% Finnsheep ewes for an autumn lambing system in this environment.