Animal diseases: causes and solutions

Taruvinga Magwiroto

At some point, your animals will get ill. That is certain. So it is important to get acquainted with what can go wrong, and how to attend to that.

What causes animal illness?

Infectious diseases

Animals get ill when they are infected by pathogens. For example animals can suffer from Foot and Mouth Disease, Anthrax or Tetanus when they get infected by organisms that cause these diseases.

Solution: The best way is to vaccinate against known diseases found in the area. Most diseases have vaccines which prevent their occurrence if an animal is injected with the vaccine.

Metabolic/Production diseases

These are diseases that are associated with physiological status of an animal. Pregnant dairy animals can suffer from milk fever, which happens when there is calcium/phosphorous imbalances in peak milk production or just after calving. Pregnant twin-bearing sheep can suffer from twin lamb disease if they don’t get adequate energy diet in late pregnancy.

Solution: You have to know the likely issues that will affect your animal at different physiological stages. High milk producers use up more calcium than they take in, so always have a supplement of calcium/phosphorous ready. Calcium and phosphorous go together.

Nutrient deficiencies

This can occur in starvation or unbalanced diet. The signs will depend on the specific deficiency. General starvation results in stunted growth and poor overall production like failure to come on heat, silent heat etc. Specific deficiencies of minerals can result in poor health. Phosphorous deficiency can result in a craving for bones, which can result in animals eating strange objects and getting infected with botulism.

Solution: As a rule, Zimbabwean soils lack phosphorous and magnesium. Supplement in the dry season. A multi-mineral supplementation is the solution in the absence of tests.

Internal parasites

Internal parasites do not cause dramatic signs. They are rather chronic ill-ness shown by ill-thrift or poor condition. Adult animals are generally resistant to the effects of worms. However, if worm burden is compounded by drought, the effects are serious. Animals lose condition. Young animals may show pot belly, anaemia and die. Sheep are especially susceptible to liver flukes.

Solution: Studies done at the Central Veterinary Laboratories (Harare) show that farmers can do strategic deworming about three times per year. April/May, Oct/Nov and Jan. As expected, the rain season favours the flourishing of worms. Dose with a broad-spectrum dewormer which kills all types of worms.

External parasites

External parasites may be a problem on their own. In chicken, think of fleas and bugs. In rabbits, mange mites can be a real bother. Ticks are probably the single most important external parasites in Tropical Africa. Their effects include sucking blood, tick worry, spreading tick-borne diseases and disrupting animal movements. Farmers have to spend a lot of money in tick control otherwise their animals die. January Disease has caused huge cattle losses in Zimbabwe in 2017/18.

Biting flies can also be a problem. Tsetse flies are associated with trypanosomiasis and midges are associated with Three Day Stiff Sickness, Lumpy Skin Disease.

Solution: Strategic dipping. Once per week in the rain season. Once in 2 week in the dry season. Though this is a guide: use your discretion in extreme circumstances.


This can occur in the veld. Certain plants are poisoning if eaten by grazing animals. Lantana camara is an example. Animals can also be poisoned by chemicals which include urea, or other salts. Heavy metal poisoning e.g copper can also happen especially in soils associated with excess of such.

Solution: Keep store rooms under lock and key. Animals tend to be poisoned after a drought because poisonous plants are the first to sprout out with the rains. Get rid of poisonous plants in paddocks. Heavy metal poisoning not common in Zimbabwe.

Leave a Reply