Time stops for no one including those with calves to vaccinate (and cows). If you haven't already done so now is the time to plan your lepto vaccinations and mark a date in the calendar.
Guidelines for a typical Manawatu herd (defined as a spring-calving herd with good colostrum management in a low summer rainfall area) are as follows:
- Calves (born Jul/Aug/Sep) are due for their first (sensitiser) dose during Mar/Apr
- Calves booster dose 4-6 weeks after sensitiser
- Cows and R2 heifers annual booster in Apr/May
Note that the calf's booster dose should coincide with the cow/heifer annual booster dose. This means that the interval between annual doses will not exceed 12 months in later years and puts all animals on the same cycle. Also remember to stick to a 4-6 week interval between the sensitiser and booster for calves. The further outside this interval, the more variable the response resulting in an increasing number of individuals without adequate immunity.
For autumn calves (born Mar/Apr), give the first dose at 12 weeks of age (May/Jun) with the booster dose 4-6 weeks later. The annual booster will then coincide with the rest of the animals in autumn. If calves are less than 12 weeks at the time of the first dose, then an additional dose is required 6 months later to ensure adequate immunity.
Variations from this protocol may occur when calves are mixed with animals that are either unvaccinated or of unknown status when sent away for grazing. This will occasionally occur before vaccinations are normally started. In this case, vaccinate calves before they leave and give an additional dose 6 months later and thereafter in autumn, as for the rest of the herd.
Other vaccines to consider at this time are 5-in-1 and BVD. The earlier these are started, the better. This is certainly recommended before mixing with other stock of unknown status, and in the case of 5-in-1, before transportation.
