Abstract 669

H Losada, J Cortés y D Grande

Departamento de Biología de la Reproducción, División de CBS, Universidad Autónoma Metropolitana-Iztapalapa, AP, 55535 México DF

Livestock Research for Rural Development 1992 4(3): 15-19.

A study was carried out to compare two feeding systems for Holstein dairy cattle fed on concentrates, lucerne hay and corncobs, carrots and broccoli. Dry matter content for carrots and broccoli was lower (8%) than lucerne hay and concentrates (91%) and corncobs showed intermediate values (34%). The protein content of broccoli (leaves and flowers) was higher (31%) than lucerne (21%), whereas this latter showed a high fibre content (23%). Cows fed on a lucerne/ concentrate diet had a lower DM intake and higher production of milk than those fed with corncobs, carrots and broccoli (20.9 kg DM/d, 18.0 kg milk/d vs 24.6 and 16.3 respectively). Intake of vegetables depressed the fat content of the milk (2.8 vs 4.6%) and increased the percentage of protein (5.3 vs 3.7%) The inclusion of corncobs, carrots,and broccoli as a feed for dairy cattle proved to be an alternative resource for milk production in situations where milk is not paid for on fat content.