Dear Dr. Othieno, Thanks so much for your insightful articles on animal health. I am a farmer from Kajiado County. I have lately noticed that many flies disturb my animals, I am not sure I can do anything about this. However, my biggest worry is ticks, which I am trying my best to control because I know they spread many deadly diseases. I’m also worried about internal parasites, which I might not see, yet they are eating up my animals internally. I would greatly appreciate any basic principles of internal and external parasite control that I can use on my farm.

[Lenku James, Kajiado County]

Dear James, thank you so much for reading the Smart Harvest and for your question. It is good that as a farmer you have already taken cognizance of the risk that pests can pose to your animals. Flies are a nuisance to livestock, their buzzing and bites create a lot of discomfort that translates into reduced production. If you are practising zero grazing, netting can key away all the flies. But let’s take a systematic look and the control of external and internal parasites. Animals are affected by various parasites. These parasites are largely grouped into two – external and internal parasites. Their presence is not associated with any benefits but health, production and reproduction issues that eat into farm profits. External and internal parasites can spread diseases in a herd, suck blood and reduce the growth rate of young animals. You do not need parasites on your farm, hence the need for a good programme to prevent their entry and to control them in your herd. 

External parasites spread animal fatal diseases like trypanosomiasis – spread by tsetse flies, tickborne fever and East Coast Fever or theileriosis spread by ticks. Other external parasites include stable, face, horn, black, horse flies, midges, mites, lice, gnats and mosquitoes. Internal parasites are further classified according to their site of predilection, for example, stomach worms prefer the digestive system. Stomach worms include roundworms, blood-sucking Haemonchus or “Barber’s pole.” There are also several intestinal worms and protozoa like Coccidia and tapeworms. The eggs or larval stages of these parasites are shed through fecal waste into the environment from where they develop into infective stages that are picked up by animals when they graze. Other include liver flukes and lungworms and as the names suggest the organs they infest and destroy in the process. It should be noted that at times an animal can have a number of these parasites and that can have a heavy toll on its health, production, and reproduction.

Parasite Control Programme

A good parasite control programme includes farm husbandry practices aimed at reducing the parasite population in the environment while at the same time controlling those already on the animal or inside the animal. Regular spraying, dipping and application of appropriate acaricides will help control external parasites. Deworming – administration of the correct anthelmintics. The application of insecticides or the administration of anthelmintics should be strategic as it is informed by the ecological conditions that determine the type and population of parasites in a certain area.

 [Dr Othieno is a veterinary surgeon and currently the head of communications at the Food and Agriculture Organization of the United Nations (FAO) Kenya. The views expressed here are not necessarily those of FAO but his own]