COWPEA HAY AS A PARTIAL SUBSTITUTE FOR CONCENTRATE: EFFECTS ON MILK YIELD AND COMPOSITION

The study was carried out in Yabello Pastoral and Dry Land Agricultural Research Center to investigate the effect of replacement of cowpea (Vigna Unguiculata) for concentrate mix on milk yield and composition in lactating Borana cows fed Rhodes grass hay as a basal diet. Four lactating Borana cows of similar milk yield, body weight and stage of lactation were arranged in 4 x 4 Latin square design. The treatments included offering Rhodes grass hay a basal diet ad libitum with different proportions of concentrate mix and cowpea hay. T1= 100% concentrate mix and 0% cowpea hay (control), T2= 65 % concentrate mix and 20% cowpea hay, T3= 65% concentrate mix and 35% cowpea hay and T4= 50% concentrate mix and 50% cowpea hay. There were no significant differences (P>0.05) in dry matter and nutrient intakes among treatment groups, while milk yield was significantly different (P<0.05) among treatments. The overall mean of daily milk yield was 4.05 kg/day. Cows that were receiving 100% concentrate mix (T1) produced the highest milk yield (4.18 kg/day) followed by cows receiving the diet in which 50% of the concentrate mix was replaced by cowpea hay (T4).Except milk yield, cowpea hay can substitute up to 50% of the concentrate mix without adversely affecting feed intake, nutrient intake and milk composition of lactating Borana cows fed Rhodes grass hay as basal diet. Therefore, to improve their milk production, smallholder farmers can use cowpea hay 50% to replace the concentrate mix in feeding their cows on poor pasture, especially during dry seasons.