Five parasite control options for your herd
Parasite control is an integral part of herd health. Internal and external parasites have negative effects on your farming enterprise as they spread diseases, reduce the quality of skin and productivity of livestock. There are several control programmes depending on livestock type, numbers, level of infestation, type of target parasites and available financial resources.
1. “Dips”/Plunge Dip Tanks
Prior to privatisation of veterinary services, community livestock dips were a common feature in virtually all villages in Kenya. Now they are significantly few. They serve a large number of livestock at ago and offer good penetration (complete wetting). They are effective in control of ticks, lice and midge.
The downside of this technique is that it is expensive to construct (it requires land and other inputs). Dips are also open to vagaries of nature for instance too much sun evaporates the dip solution while runoff from rain dilutes the wash.
Luckily, this can be minimised at the design stage. Dips are a ‘no no’ for pregnant animals and calves. For sheep and goats, a handler is needed to make sure they do not turn back or drown in the tank.
Over dilution of the dip is also a major challenge. The design should take care of underground slippage which can result in environmental pollution. Animals are also prone to injuries when they use dips.
2. Spray Races
This is a complex connection of pipes and nozzles arranged in a passage. It is gentle and safe for pregnant and young stock. The concentration of the wash solution can be maintained and it can deliver just the right pressure for complete wetting and penetration. The structure can be constructed in a way that the solution is filtered and reused saving on costs.
The disadvantage of spray races is they are expensive and the nozzles prone to blockages hence pressure may not be enough. The wash may also not penetrate the ears and tail areas where ticks are known to hide.
3. Topical Treatment – “Pourons”
Pourons are oil-based acaricides that come with a spreading agent. They are applied on the backline, spread throughout the body and have a residual effect (remain potent on the skin). They require no dilution making them practical in dry areas where availability of water is a challenge.
Pourons are effective against ticks, midges and fleas. However, pourons require a dry coat for effective action, when applied on a wet skin or if it rains immediately after application the efficacy is reduced. They also do not work well with sheep due to a lot of wool which lowers penetration. Pourons are however relatively expensive.
4. Hand or leg sprays “Knapsack sprayers” and “Rocking sprayer”
The knapsack sprayers are good for a small number of animals like sheep and goats. Rocking sprayers are operated by foot and generate more pressure compared to the knapsack sprayers. Rocking sprayers can be used for many animals and have a pressure that can penetrate hidden areas like ears, base of the horn and the undersides with good spraying skills. The person spraying needs to direct the nozzle for proper wetting.
There are several injectables available in the market for control of external and internal parasites. They should only be administered by a veterinary doctor as wrong administration can be fatal.
6. Hand Dressing
This involves the use of grease or oil-based acaricides smeared on parts that are likely or already affected by external parasites. They also have a residual effect and will act for a long time after application. This technique should be used alongside others for complete control of parasites.
Ensure livestock are not thirsty prior to dipping to avoid accidental drinking of the acaricides. In dips and spray races, include a hoof bath to wash off dirt and reduce contamination of the acaricide. The best time to apply acaricides is always in the morning.
[The writer is the vet of the year in 2016 and works with the Kenya Tsetse and Trypanosomiasis Eradication Council (KENTTEC) – [email protected]]