This study was conducted to examine the effect of different levels of vetch hay
(Vicia dasycarpa) supplementation on feed intake, milk yield and milk composition of 50:50 Boran-Freisian crossbred dairy cows fed a basal diet of Napier grass (Penissetium purpureum). Five crossbred dairy cows at an early stage of lactation with average milk yield of 6 – 8 liters/cow/day and body weight of 390 ±15 kg (mean±STD) were arranged in a 5*5 latin square design. In the first 4 treatments, Napier grass was fed ad libitum as basal diet, while in T5 (the control diet) native hay was the basal diet. In treatment 1, 2 and 3 vetch hay was supplemented at 20% (2.4 kg), 30% (3.6 kg) and 40% (4.8 kg) replacement of the total daily DM intake, respectively. In T4 and T5
concentrate mix (55% wheat bran, 43% noun seed cake (Guotie Abyssinia) and 2% salt) was supplemented at the rate of 0.5 kg per liter of milk produced. Total dry matter intake differed among treatments in the order of T4>T3=T5>T2>T1. Milk yield was greater for concentrate supplemented treatments compared with the vetch supplemented ones, and was similar (P>0.05) among the different level of vetch supplemented groups. Milk fat and protein were not affected (P>0.05) by treatments. In general this study indicated that optimum milk production (8.81 liter/cow/day) can be obtained with the use of Napier grass supplemented with 2.4 kg/cow/day vetch hay dry matter.