Of all the animal parasites, ticks are one of the most stubborn. They are a menace and can cause havoc of monumental propositions despite their miniature stature. They transmit some of the most economically important animal diseases, affecting both productivity and profitability of livestock. Their irritation affects animal feeding, which reduces intake, subsequently reducing milk yield and weight gain. The cost associated with tick management is huge, especially because many of them develop resistance to acaricides pretty fast. The eradication of ticks is a pipe dream and the key goal is to keep them in check.
Proper and effective management of ticks is based on several factors:
- Understanding the biology of ticks.
Ticks are not all the same. They differ in size, shapes, colour and predilection sites (preferred sites of attachment on a host). Equally, there are species’ differences in their biology. Of paramount importance in regard to their management is the life cycle. Generally, ticks undergo metamorphosis from egg, larva, to nymph and adult. Some ticks will climb onto the host, at the larval stage after hatching and stay until they become adults. The females will then drop off to lay eggs after mating. Such a tick is called a one-host tick. Others will parasitise on different hosts across their life cycles. They are either two-host or three-host ticks. It is important to understand the specific tick to be controlled in this respect, as it will influence the frequency of application of an acaricide. As a diligent farmer, consult your veterinarian to examine the ticks in your farm and institute a corresponding tick control strategy;
- Understanding the acaricides
Although this is not the only method of controlling ticks, it is the most common. Acaricides are chemicals used to kill ticks and mites. They are mainly used in dips or applied using sprayers. There many classes of chemicals used, including organophosphates, carbamates, pyrethrins & synthetic pyrethroids among many other classes.
Development of resistance is the major challenge in use of acaricides. This means that once effective acaricides can lose their potency and have no effect on the ticks. Many farmers grapple with this reality. Additionally, the acaricide’s environmental degradation and residues of the same in animal products are important aspects to consider in their use.
Most farmers do not understand the active chemical in an acaricide. Since the same compound can be traded by different companies under different names, farmers just change the trade name on the packaging, oblivious of the fact that the compound is the same and this fuels resistance. It is paramount for farmers to seek professional advice as they design an ‘acaricide rotation’ schedule. Additionally, these chemicals must be used properly and prudently according to the manufacturer’s guidelines;
- Integrated tick control
For effective tick control, a series of complementary measures must be put in place. As we have seen earlier, there is no magic or wonder drug to wipe out ticks. As a farmer, you must be deliberate in the endeavour to control these little menacing creatures.
First, it is advisable that animal breeds are selected with their tolerance in mind, especially in areas where tick-borne diseases are a big problem.
Manage your grasslands to ensure that there are reduced populations of ticks. This can be achieved by rotational grazing, alternating crops and pastures as well as alternating animals that utilise the pastures for example alternating sheep with cattle.
Thirdly, proper use of acaricides is important. Acaricides rotation should be practised as informed by your animal health professional. The more you keep the tick population in check on your farm, the less trouble they give. For farmers with different species of animals, ensure that you control ticks in all, including chicken. Dogs are especially notorious for bringing ticks to your farm from their errands.
Finally, tick-borne diseases are expensive to treat. Please make tick control a priority.
Dr Nderitu Nyaga, BVM, MSc,
Department of Veterinary Anatomy and Physiology,