Balancing rate of genetic gain, diversity and environmental impact

A number of conflicts, e.g., between the desires to achieve both accurate breeding values and high selection intensity, will occur when designing a breeding programme. Consequently, various issues must be considered to optimize the programme. The scheme giving the theoretically highest genetic gain may also not always be the best. For example, applying the highest selection intensity might be biologically possible and will in the short run lead to large genetic improvements. In the longer run, however, problems with inbreeding maybe encountered due to the faster narrowing genetic base. It is also well accepted that progeny testing provides excellent opportunities to achieve high accuracy in estimation of breeding values, but the test resources required leave little room in smaller populations for use of the reliably tested selected animals. Selection based on progeny testing also prolongs the generation intervals, contributing to reduced genetic progress. In intensive production systems large inputs, e.g., of feed resources and health care, may for a time provide the largest genetic improvements and favour certain genotypes. Later, shortages of resources may not allow the expected gains to be realized. Therefore, the design of a breeding programme must accommodate a whole range of complex considerations to provide an optimum solution for the genetic resource utilization. Designing a sustainable breeding programme means finding the best compromise among all factors that determine the success of the programme. This could be short and long term. In many situations, use of young bull schemes would be a better option than engaging in poorly organized dairy cattle progeny testing scheme (See computer exercise on breeding plan).

Although it is a delicate issue to optimize a breeding programme for a given population considering genetic factors and the population structure, several external factors are necessary for the programme to be sustainable. Farmers’ acceptance and involvement and appropriate infrastructure have been pointed out earlier, and the KISS principle. A sustainable breeding program should incorporate robustness of the system so that it may withstand externalities such as climatic problems, disease outbreaks, political instability and lack of continuity in organization of the activities. Thus, it is important to align with strong organizations with a common interest of improved livestock use and production.