|
The shift from selection on milk yield alone to multi-trait selection that includes milk component and fertility traits in dairy buffaloes was explored using selection index to achieve favourable responses for 4 traits. This was done in recognition of the value of milk components of dairy buffalo milk to milk processors and the need to improve reproductive performance. Economic values per trait were estimated based on a 100-cow farm production model and used these for a base Index (I1). Three other indices were tested by varying weights applied to individual traits. Favourable responses were achieved for all objective traits in all 4 indices but were predicted to result in lower fat and protein percentage after 25 yrs. of selection. The index, I4, gives the lowest reduction in fat and protein percentage without severely compromising milk yield and calving interval and can be an alternative to I1 index. Three breeding strategies were simulated using I1 index: use of progeny test bulls resulted in smallest net present value; use of young bulls or inclusion of village cows in the breeding program showed higher net present value and earlier return on investment. Positive return on investment is delayed, realized only after the 8th year at the earliest in all 3 strategies. As 99% of buffaloes are smallholder's farms, investment in genetic improvement is unlikely to be funded other than by the government in the Philippine situation. |
|