Rose Jackson BVSc DBR MRCVS (Partner) explains how to protect your heifers from Lungworm.
Lungworm (husk) disease outbreaks are becoming more prevalent and unpredictable.
An independent survey last year found that 40% of dairy farmers interviewed had heard cattle coughing at grass, and over a third of milk producers said that they had had lungworm confirmed in their stock at some point over the last three years. More concerning was the age group spread for the lungworm incidence. As might be expected, half the disease outbreaks were reported in dairy young stock during their first grazing season, but 40% occurred in second season grazers and even 38% in adult cattle. This suggests that animals are not developing lifetime immunity to this debilitating disease, as often used to be the case.
Nearly two thirds of the lungworm cases were reported in the autumn, and the rest in the summer. Planning husk control strategies for young stock prior to their first grazing season makes sound financial sense; relying on wormers alone often doesn’t really allow the animal to develop its own natural immunity.
How Does Lungworm Occur?
Lungworm occurs as a result of infection with the worm Dictyocaulus viviparous. Cattle develop the condition after eating grass contaminated with infective larvae. Once in the gut, the larvae migrate through the gut wall to the lungs where they begin laying eggs after several weeks.
A spell of mild, wet weather can create a sudden, dramatic increase in lungworm populations, which can be very harmful, and even fatal, to any stock that have little or no immunity.
Bovilis Huskvac Vaccine
Bovilis Huskvac is a live vaccine made from irradiated larvae which are incapable of causing disease. For dairy calves, vaccination should be completed at least two weeks before the calves are turned out to grass. For suckled calves, the vaccine course should finish two weeks before the calves begin to eat significant amounts of grass. Wormers should not be given until two weeks after the final dose of vaccine.
The vaccine produces a very good immune response against disease, but it does not prevent the normal worms from completing their life cycle. This allows for the continued development of natural immunity, which often fails to occur where there is an over-reliance on wormers.
Vaccination with a pre-turnout course of Bovilis Huskvac is the most reliable and cost-effective way of ensuring the development of immunity to lungworm.
Please contact the practice to plan your lungworm control strategies for this season and to order Bovilis Huskvac.
