Figure 4-12Life cycle o round worm in sheep
EXTERNAL PARASITES These parasites live on the outside of the animals. Ticks: These suck the blood of the animals and cause anaemia. When ticks bite an animal, they cause irritation which results in an itch. Itching causes restlessness and damage to the skin of the animal. These lesions are openings for other external parasites. Prevention and treatment:
Ticks can be treated with tickicide, e.g., Bercotox.
Rotational grazing also controls the infection by ticks in pastures.
Lice: These can be spread by contact and infected animals become itchy and restless. They rub themselves against trees and fences causing damage that can lead to secondary infection. Prevention and treatment: Lice can be treated in the same way as ticks by:
Dipping, spraying or dusting with an appropriate chemical.
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