Development of a breeding program for improving the milk yield performance of Butana cattle under smallholder production conditions using a stochastic simulation approach

Abstract

Butana is one of the local dairy cattle breeds of Sudan commonly kept by smallholder producers. This breed has been strongly promoted to advance the dairy production sector in the country. The main problem, however, is the lack of a systematic breeding program that involves smallholder producers. The aim of the current study was to identify the most promising design for a breeding program to improve the milk yield performance of Butana cattle under smallholder production conditions. In total, 3 breeding scenarios, including (1) the use of farm bulls, (2) the use of village bulls, and (3) the rotational use of village bulls within village groups, were simulated using a stochastic simulation approach. For each breeding scenario, 3 selection methods for bulls were considered, namely random mating, phenotypic selection, and selection based on estimated breeding value (EBV). The results showed that no genetic gain was realized with random mating in all breeding scenarios. In the farm bull breeding scenario, annual genetic gain (standard deviation units) ranged from 0.01 to 0.19 (phenotypic selection) and from 0.01 to 0.39 (selection based on EBV). In the village bull breeding scenarios, the annual genetic gain ranged from 0.01 to 0.21 (phenotypic selection) and 0.01 to 0.45 (selection based on EBV). The lowest genetic gain was realized for the rotational use of village bulls among villages within groups. Through the rotational use of village bulls, however, a higher genetic variance was maintained than in the farm and village bull breeding scenarios. We concluded that a village bull breeding program with selection based on EBV of young bulls was the most promising breeding design for achieving the breeding goal. Further studies are needed to assess the organizational feasibility of such a breeding program to ensure the participation of smallholder producers and its sustainability.

Cattle Genetic Improvement Strategies for Sustainable Development in Tropics: Review

“…After one or two years or seasons, he should return the bull to the center. Lower genetic gains achieved with the farm bull breeding scenario in the current study compared to the village bull breeding scenario showed that individual farmer attempts to advance genetic diversity are difficult due to limited herd sizes (Elhady et al, 2022). Additionally, inbreeding and the ongoing selection of farm bulls within a farm herd are most likely to blame for the considerable loss in genetic variation under the farm bull breeding situation (Gorjanc et al, 2015).…”

“…The sires are provided from a different subpopulation than the dams (Windig and Kaal, 2008). According to Elhady et al (2022), rotational mating achieved lower genetic gain than the village bull breeding scenario. This could be attributed to the low number of selection cycles for bulls in the simulated rotational breeding scenario because, on average, bulls were rotated 4 to 6 years before the selection of young bulls was carried out to replace the old ones.…”

“…A higher genetic variation can be maintained as a result of the rotating usage of village bulls within village groupings. By balancing the genetic contributions of the breed's subpopulations, rotational mating may generally be used to promote the genetic diversity within a breed (Windig and Kaal, 2008;Mucha and Komen, 2016;Elhady et al, 2022). The Butana region does not have a usual practice of rotating the usage of village bulls among villages within groups, which increases organizational complexity.…”

“…The Butana region does not have a usual practice of rotating the usage of village bulls among villages within groups, which increases organizational complexity. As a result, the willingness of farmers to accept such a breeding program needs to be examined (Elhady et al, 2022).…”