Dry matter in take, milk production and physical measurements of crossbred dairy cows supplemented with varying levels of concentrate
2003
Zelalem Yilma(Holetta Agricultural Research Center, Holetta (Ethiopia)) | Tadesse Bekele(Holetta Agricultural Research Center, Holetta (Ethiopia)) | Yohannes Gojam(Holetta Agricultural Research Center, Holetta (Ethiopia)) | Alemu Gebrewold(Holetta Agricultural Research Center, Holetta (Ethiopia))
An experiment was conducted to determine Dry Matter (DM) intake, milk yield, body weight and linear body size of 22 50% and 75% exotic crossbred lactating cows of Friesian and Jersey exotic sire breeds and Boran local dam breed under two levels of concentrate supplementation (3 and 5 kg/head/day). Cows were grouped into the two supplementation groups based on parity, breed and exotic blood level. Total milk yield, milk yield per metabolic body weight, live weight, metabolic body weight, body condition scores, wither heights and heart girth were considered. Data were analyzed using General Linear Model (GLM) procedures of the Statistical analysis System (SAS). Results indicated that daily DM intake were higher for cows supplemented 5 kg concentrate per head per day than those supplemented 3 kg per head per day (p0.05). Daily DM intake was not different (p0.10) between parity groups, breeds and exotic blood levels. Total milk yield increased with higher level of concentrate supplementation (p0.05). Cows with advanced parities, Friesian crosses, and 50% crosses produced 210 kg (16%), 139 kg (11%) and 5 kg (0.4%) more milk than cows with early parities, Jersey crosses, and 75% exotic crosses, respectively. Cows supplemented with high level of concentrate were higher in body weight and linear body measurements, than cows supplemented with low level of concentrate. Regression analysis indicated that there was a positive linear relationship between body weight and heart girth. Milk yield per unit metabolic body weight was not different between concentrate supplement levels, parities, breeds and exotic blood levels (p0.05).
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