A field investigation of performance and economic efficiency of working buffaloes was carried out in the Mekong Delta (MD) provinces of Vietnam (Hau Giang, Kien Giang, An Giang and Dong Thap). The size of the buffaloes in Dong Thap and Hau Giang appeared to be larger than in the other provinces, while reproductive performance of female buffaloes was better in An Giang. Economic efficiency of buffaloes was better than that of tractors in the MD. It was found there was a changing role of buffaloes, with their use to transport rice from the paddy fields being more important than their use for cultivation. Traditional feeding was still dominant and there appeared to be limited support for buffalo development programs which could enhance their role in the Delta. It was concluded there was an urgent need develop more appropriate feeding systems, and that breed improvement should be considered urgently to improve buffalo breed quality and income to the farmers.
In a digestibility and growth experiment, four growing buffaloes (mean LW 226 kg) and four growing local cattle (mean LW 145 kg) were allocated to 4 diets according to a 2*2 factorial within a double Latin square design (one for each species). The main coarse feed was para grass (1% body weight, DM basis) and rice straw fed ad libitum. The supplements were 150g and 200g crude protein (CP)/100kg LW/day from Sesbania grandiflora foliage and urea, or from cottonseed cake. The periods on each diet were 28 days with measurements of digestibility and N balance over the last 6 days.
DM intake did not differ between cottonseed meal and sesbania plus urea supplementation; but was higher for the 200g CP level than the 150g level. There were no differences between species when DM intake was expressed on the basis of metabolic live weight but daily weight gain was higher for buffaloes. The DM and NDF apparent digestibilities were higher in buffaloes than in cattle (53 vs. 49.9 % and 57.9 vs 54.0%).. Crude protein apparent digestibility did not differ between species but was higher for the higher level of CP supplementation. Ruminal NH3-N concentration was higher with the 200g CP level than with 150 g CP, both before and 3 hours after feeding. Daily N retention was higher in buffaloes than in the cattle and this was reflected in higher live weight gains for the buffaloes.
It is concluded that cottonseed meal and foliage of Sesbania grandiflora plus urea have similar properties in providing rumen fermentable nitrogen and bypass protein for cattle and buffaloes fed rice straw and grass basal diets.