Winter cattle drenching
This time last year, the weather had really packed in, feed was scarce and the wheels really started to fall off some of the cattle systems around the district. There were many compounding issues; however, the final nail in the coffin for many cattle was parasites. If the drench programme was anything other than perfect, there was no slack in the system and much stock became compromised or worse.
Once cattle are approximately 10 months of age, the dominant worm species becomes Ostertagia. Many Ostertagia larvae ingested in the autumn and winter become dormant, recommencing their development in spring and causing ‘type 2 ostertagiasis' when they emerge. Animals under pressure are most at risk but this phenomenon may occur in well-conditioned animals too, following a flush of feed. Cattle usually become immune to Ostertagia from about 15 months of age. This is not the case with the inhibited form of the worm though, and disease can be seen in older cattle.
By the time cattle are approaching 12 months of age, they should have developed resistance to Cooperia. This worm is usually a problem in the summer and autumn in R1 cattle. Trichostrongylus can be present right through until the spring but their main significance is as a component of a mixed infection.
R2 cattle or older should receive a drench coming out of the winter to remove the inhibited Ostertagia burden. An injectable ‘mectin' drench is easier than an oral one and should be more effective than a pour-on.
R1 cattle are in that middle ground where Ostertagia will be an issue and Cooperia may still be on the scene. An appropriate drench to use would contain levamisole and a ‘mectin'. These are available in oral, pour-on and a now injectable. "Eclipse E" is an injectable combination that was launched by Merial Ancare last month.
If you have any questions about drenching your cattle this winter please come and talk to us. It is important to get it right.
