PhD defence
Evaluation of the nutritional values of local grasses for dairy cattle in Vietnam
Summary
It is often argued that the content of fermentable organic matter (FOM) in tropical
roughages is low and that this is the reason for the low milk production and milk
fat synthesis by dairy in some Southeast (SE) Asian countries. In practice, the
FOM contents of roughages, including fresh grasses, is largely unknown because
they are not routinely assessed in SE-Asian countries. The research described
in the thesis investigated the FOM content of tropical grasses commonly found
in Southeast Asia to determine if milk fat can be increased. The research
employed an in vitro automated gas production assay and the well-established
nylon bag technique to assess the degradation of grasses in the rumen of dairy
cows, as well as a digestibility trial in sheep. The research provides
recommendations for optimizing the harvest times of tropical grasses and diets of
dairy cow to enhance milk production and milk fat content, particularly in Thailand
and Vietnam.