^66 Insects attacking cattle. 



stage to provide for. The flies are in most cases very active and 

 fly from animal to auimal, but tliey often stay in the hair or 

 feathers of a single host for a long period. 



Bot Flies. 



A number of flies do not feed themselves on the blood of cattle, 

 but their larvae live in their tissues. These larvse are known as 

 bots or warbles and have been found in India in sheep, cattle and 

 liorses. The sheep bot-fly deposits eggs or living maggots in the 

 nostrils of the sheep, the maggots crawling up the nostrils and fixing 

 themselves upon the mucous membrane of the nasal cavities. They cause 

 great irritation, much mucus is produced, on which they feed and they 

 injure the delicate nasal membranes. The maggot remains there until 

 nearly one inch long, when it loosens its hold and is thrown out on the 

 ground; it pupates in the ground and the fly presently emerges. The 

 remedy is to prevent the fly from laying eggs by rubbing the nostrils 

 with tar, train oil or other sticky applications, whose smell drives off the 

 fly and renders egg-laying impossible. 



The horse bot-fly lays eggs on the hair of the mane, the shoulder, 

 the knee or some other part within the reach of the borsch's mouth. 

 These eggs are fixed to the hair and when the maggot hatches, it is 

 licked off by the horse and swallowed; it then attaches itself to the 

 membrane by means of the hooks in the mouth and feeds by suction. 

 When full fed it passes through the alimentary canal to the ground where 

 it transforms to the pupa and emerges as a fly. 



The cattle bot or warble-fly is found as a larva under the skin 

 of cattle, buried head downwards in the tissues with the hind end of the 

 body towards the oj)ening in the skin ; air is obtained through this 

 opening and drawn in by the two large spiracles on the last segment. 

 The maggot feeds upon the putrid matter produced in the sore ; when 

 full grown it forces itself back through the opening in the skin and falls 

 to the ground, where it pupates. This insect causes a large amount of 

 damage to the hides, warbled hides being of very inferior value. The 

 condition of the infested animal is also bad. Treatment for this and for 

 other bot maggots is a veterinary matter, which should have the litten- 

 tion of a qualified veterinary man. It takes the form of sticky smelly 

 mixtufes to prevent egg-laying, the removal of bots from the skin by 

 pressure or the desti'uctiou of bots by ajiplication of grease or ointment, 

 ^hc species discussed above al'c the most common in India, as elsewhere. 



