Herbal drugs and their effects on rumen ecology of cross breed calves

In most of the developing countries cereal grains are not available in sufficient quantity for livestock feeding and it is a need of present scenario to search certain alternate energy sources. Use of herbs as a feed additive not only improve feed efficiency but they may have an equal effect on daily gain and it have also secondary benefit which reduces the incidence of metabolic & causative diseases while others suppress the microbial population which causes of methane gas formation. Therefore day by day interest is increasing in exploiting natural products as feed additives to solve problems in animal nutrition and livestock production. Thus new methods must be found which will enable farmers to manipulate rumen fermentation to obtain benefits from their animals. Among these new methods the great diversity of secondary metabolites occurring in plant species offers tremendous opportunities for development of rumen protozoa that can play an important role by contributing nutrients to the host animal.