Various external parasites

1. Lice:

• Lice are wingless, dorsally flattened, ectoparasites. Lice infest a wide range of domestic livestock, including pigs, cattle, goats, and sheep, and cause a chronic dermatitis, (inflammation of the skin) characterized by constant irritation, rubbing, and biting of the hair or fleece.
• Goat lice are host specific and only attack goats and their close relatives such as sheep.
• Lice are divided into two main groups: the Anoplura (sucking lice) and Mallophaga (chewing or biting lice). Lice cause skin irritation and itching.
• Infested cattle can experience reduced appetite and appear unthrifty.

2. Mites:

• Goats can be infested by several species of mites, but the species more commonly found on goats are goat follicle mite (Demodex caprae), scabies mite(Sarcoptes scabiei), psoroptic ear mite (Psoroptes cuniculi), and chorioptic scab mite (Chorioptes bovis).
• Mites feed on the surface or burrow within the skin, making very slender, winding tunnels from 0.1 to 1 inch long.
• The fluid discharged at the tunnel openings dries to form nodules. A toxin is also secreted which causes intense irritation and itching.
• Infested animals rub and scratch continuously. Infestations are contagious and treatment of all animals in a herd is essential to achieve control.

3. Fleas:

• Adult fleas are small (1 to 8 mm), wingless insects that are narrow and are compressed on the sides with spines (combs) directed backwards.
• Most species move a great deal and remain on the host only part of the time to obtain a blood meal.

4. Ticks:

• Ticks harm their hosts by injuries caused by their bites that result in blood loss and transmission of disease pathogens.
• Ticks cause blood loss, discomfort, and spread diseases like anaplasmosis.
• High concentrations of ticks usually occur in brushy pastures and woodlands so habitat management is an important part of tick control.