The effect of peri-parturient anthelmintic treatment on the productivity of dairy cattle in subtropical western India.

Trials with fenbendazole (Panacur, Hoechst India Ltd) were carried out on two commercial farms in subtropical western India to study the response and economics of nematode treatment in adult dairy cows. Milk yield, lactation length, time to first oestrus and worm egg output were monitored in treated and control groups. Treatment reduced the egg count considerably. Treated cows produced 142 litres more milk over 100 days (p < 0.05), with extension of lactation length and advancement of time to first oestrus. The economic gain in terms of milk yield far outweighed the cost of anthelmintic used.