Deworming schedule for cattle and buffalo
When to deworm, what to use at each stage, and how to avoid breeding resistant worms.
Internal parasites cost more in lost growth and lost milk than in visible illness. Animals rarely look sick; they just do not thrive.
A workable schedule
| Stage | Timing | Notes |
|---|---|---|
| Calves | First dose at 6-8 weeks, then every 3 months to 12 months old | Most vulnerable group; worm burden here shapes lifetime growth |
| Young stock | Every 3-4 months | Time one dose to the end of the monsoon, when pasture burden peaks |
| Adults | Twice yearly, before and after monsoon | Plus at drying off, on veterinary advice |
| Pregnant animals | Avoid the first trimester | Some actives are contraindicated in early pregnancy - check the label |
Dose by weight, not by eye
Underdosing is the main driver of resistance: it exposes worms to a sub-lethal dose and selects for survivors. Weigh the animal or use a weigh-band. If you must dose a group to one weight, dose to the heaviest, not the average.
Rotate actives, not brands
Two products from different companies containing the same molecule are the same treatment. Rotate between chemical groups - a macrocyclic lactone such as ivermectin, a benzimidazole such as albendazole - roughly once a year, not every dose.
Withdrawal periods
Dewormers carry meat and often milk withdrawal periods, and some are not licensed for lactating animals at all. Ivermectin in particular has a long meat withdrawal and is generally not for use in animals producing milk for human consumption. Check the label before treating a milking animal.