Effects of Sorghum Stover as Replacement Basal Diet on Milk Yield, Live Weight and Dry Matter Intake of Friesian Cows in Botswana

摘要

Thirty-four lactating Friesian cows were allocated to two groups. At the beginning of lactation two cows were paired according to parity, weight and date of parturition. One group was randomly allocated to stover-based diet (SBD) and another to grass-based diet (GBD). The basal feeds (stover or grass) were given on ad lib basis. Lucerne and dried brewers grain were fed on group basis in the drylot. Dairy meal was given individually according to milk yield at rate of 500g/litre after the first 8 litres. Daily intake of Lucerne, brewers grain and the basal feeds were significantly different (P0.05) in take of dairy meal was observed between the treatments. Stage of lactation was found to influence daily intake of Lucerne, brewers grain (P0.05) between the treatments. SBD cows produced more milk (P0.05) between the treatments. Based on the similarities of body weight, body condition score and milk composition between the treatments and the high milk yield by SBD, sorghum stover can thus be used to feed fat cows during lactation. This will stimulate mobilization of body fat. However, since energy intake would limit milk yield in the long run, a high-energy feedstuff such as silage need to be introduced to maintain high milk yield. Too much reliance on body condition as a buffer to overcome nutrition shortcomings, such as the case with stover fed cows, would lead to reduced milk yield in cows with insufficient body reserves.