The relationship estimates amongst milk yield and milk composition characteristics of Bunaji and Friesian × Bunaji cows

Abstract

The milk yield of 24 Bunaji and 26 cross breed (Friesian × Bunaji) cows were analyzed for milk yield characteristics [Initial milk yield (IY), peak week yield (PWK), peak yield (PY), end of lactation yield (ENLY), lactation length (LL) and total milk yield (TMY)] and milk composition [fat, crude protein (CP), solid-not- fat (SNF), total solid (TS) and ash]. The relationship within and between the milk yield characteristic and milk composition was analyzed. The results show that PY, PWK, ENLY and LL were positively and significantly correlated with TMY (P 0.05) except with ash (r = 0.267). The relationships of milk fat with ash, SNF and TS was significant and positive (P 0.05) correlated with milk yield characteristics; the relationship was positively low for IY and PY and negatively low for PWK, ENLY, TMY and LL. Milk ash was significantly (P < 0.05) and negatively correlated with PY, ENLY, TMY and LL (r = 0.315 to 0.0577). In view of the relationship that exists within and between milk yield and milk composition characteristics, it is therefore suggested that, a milk selection index that will incorporate both milk yield and milk composition characteristics in a more balanced manner would help in improving the milk yield and milk composition characteristic of the dairy cows. Key words: Bunaji, Friesian × Bunaji, milk yield, milk composition.