Nutrient utilization efficiency of lactating crossbred dairy cows supplemented different levels of concentrate diets
2003
Tadesse Bekele(Ethiopian Agricultural Research Organization, Addis Abeba (Ethiopia)) | Zelalem Yilma(Ethiopian Agricultural Research Organization, Addis Abeba (Ethiopia)) | Yohannes Gojam(Holetta Agricultural Research Center, Holetta (Ethiopia)) | Alemu Gebrewold(Holetta Agricultural Research Center, Holetta (Ethiopia))
Twenty-two 50% and 75% exotic blood Friesian x Boran and Jersey x Boran cows were grouped into two different concentrate supplement levels (hay and lib and 3 or 5 kg/head/day). The cows were assigned to the two diet groups by stratified by parity, breed type and exotic blood level. Data collected were analyzed using General Linear model (GLM) procedure of the Statistical Analysis System (SAS). Roughage dry matter (DM) intake per live weight and per metabolic body weight was not different between concentrate diet supplement levels, parities, and exotic blood levels (p0.05). The effect of concentrate diet supplement level and breed type, however, markedly (p0.05) affected concentrate DM intake per live weight and per metabolic body weight, while total feed DM intake per live weight and per metabolic body weight was significantly (p0.05) affected only by breed type. Cows supplemented 5 kg/head/day were more efficient in milk production than cows supplemented 3 kg/head/day. Jersey crosses and crosses of 75% exotic blood levels were found to be efficient milk producers than Friesian crosses and crosses of 50% exotic blood levels, respectively. Metabolizable energy (ME) and digestible crude protein (DCP) balance were higher for cows fed higher supplementary feed level during lactation. Gross efficiency of ME and DCP for milk production were better for cows with early parities, Jersey crosses of 50% exotic blood inheritance, respectively. Supplementation of 5 kg concentrate improved feed DM intake, feed conversion efficiency and, nutrient utilization.
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