Plan your herd health to ensure cattle are ready to thrive this winter
October 20, 2021
A parasite burden in any animal causes both economic loss and disease. By definition a parasite is an organism that benefits from living on another animal, and the animal (the ‘host’) suffers but normally will not die. Having an effective parasite control programme planned for your cattle is essential to optimise the health of your herd over the winter period. CAFRE Beef and Sheep adviser Rachel Megarrell recommends that “A control programme needs to consider two elements; endoparasites which live within the body of their host and also ectoparasites which live on the outside of the host. Choosing the right product and getting the most from it are key factors in ensuring optimum cattle performance for least cost and reducing the risk of anthelmintic resistance”’
Type II Ostertagia (winter) is usually seen in yearlings, following their first grazing season. Larvae that are eaten in September do not go through normal development but instead remain dormant in the gastric glands of the animal. If these are not eliminated there is the potential for thousands of larvae to simultaneously develop to adults and emerge in early spring. To pre-empt this a wormer that is effective against inhibited larvae should be used at housing. In general adult cattle over 2 years of age will have built up a natural immunity to worms, however any symptoms such as poor thrive, weight loss or reduced appetite should be investigated via diagnostic tests in conjunction with your vet.
In terms of liver fluke, there are a variety of products available on the market to target this parasite but it is important to understand that different products kill different stages of fluke. Fluke takes 3 months to develop in the liver of cattle or sheep. The first month they are called “early immature”, the second month they are called “immature” and the third month they are known as “adults”. The fluke attack the liver, the animal fails, becomes anaemic and may be jaundiced. Fluid may collect under the jaw known as ‘bottle jaw’.
Rachel advises that “it is important to use the life cycle of the fluke to control the disease”. When cattle are moved off grass they do not eat any more fluke, therefore if you dose immediately with a drug that kills only adults you will leave all young flukes under 8 weeks to live and grow in the liver and cause disease. With low levels of infestation or numbers of fluke you could wait and dose 6 weeks after housing, this means that any fluke picked up while grazing will have matured to stage where the treatment provided will be effective. A product that contains the active ingredient Triclabendazole is suitable for use at this stage as it will target the young fluke. You do however need to carefully consider previous incidence of fluke prevalence on your farm alongside changeable weather patterns experienced in recent years.
Lice infestation can also commonly occur during the winter housing period. This causes irritation, biting behaviours, ill – thrift and poor growth rates so it is essential that this is treated in a timely way. Mange mites are very small and can’t be seen with the naked eye but they will burrow into the skin of the animal causing intense itching and loss of condition. A popular control method to combat these external parasites would be the use of a pour on product.
Finally remember that it is important to always refer to the product data sheet and follow the procedures laid out correctly for any product to be used. Herd health is a crucial part of your management regime and as always, if in doubt or you have concerns about the health of your herd then veterinary advice should be sought immediately.