98C Parasitic Insects. 



Two or three repetitions of the treatment after 3 to -4 days 

 appear to be indicated in order to destroy the parasites as they 

 hatch from the eggs. By washing with vinegar the eggshells 

 will be dissolved and the embryos killed. Clipping the hair ma- 

 terially facilitates the destrnction of the parasites; in horses, 

 however, it should (according to Wohler) be undertaken only if 

 numerous parasites are present, since the soaked hair prolongs 

 the effect of the anti-parasitic remedy. In winter the treatment 

 of a large herd of horses may have to be omitted, the measures 

 being directed only to the prevention of a further spread of the 

 parasites by treating and isolating the manifestly affected 

 horses. 



Against feather mites the parasiticides may be employed, 

 which have previously been recommended as suitable for birds 

 (see page 982). Careful cleanliness and skin hygiene aiford the 

 most effective protectives against lice and similar parasites in 

 general, and play an important part in the treatment. If the 

 atfection obtains a considerable extension, disinfection of tlie 

 barns and of any objects with which the affected animals come 

 in contact is indicated. 



Literature. Biihler, Expenii. inul klin. T'nters. iiber Wert mid Wirkinig <1. 

 Kreolinliniiiientes, Diss. Giessen, 1909 (Lit.)-— Wohler, Z. f. Vk., 1906, 219. 



B. Diptera. (Flies.) 



(a) Long antennaed (Nematocera). These are small in- 

 sects whose larvae develop in water, damp earth or shady places ; 

 in the mature condition they feed on plant juices, but the females 

 of some varieties also attack domestic animals and suck blood. 



Of the gnats the following are noteworthy: 



The stinging gnat (Culex pipiens) prefers the skin of man, 

 ])ut now and then also stings animals and produces painful 

 swellings on them. 



The sand flies (Simulia') are much more important in this 

 respect. The Simulia reptans and the Simulia cinerea cause 

 inflammation on the thin hairless parts of the skin of the horse, 

 for instance on the inner surface of the thigh, on the internal 

 upper surface of the ear, which only heals gradually and with 

 desquamation. The Simulia reptans appears at times in great 

 swarms and causes fatal results. Thus in May of 1881, in 10 

 townships of an Upper Hungarian county, 37 head of cattle and 

 4 horses died as a result of their ])ites. In Sweden (Schonen 

 province) gnats occur especially in hot summers and attack cat- 

 tle, horses, and also sheep. The Simulia ornata may also occur 

 in similar swarms (in one instance out of 170 cattle that were 

 stung, 27 died), and, according to Dammann & Oppermann, may 

 transmit the infection of hemorrhagic septicemia in deer and 

 cattle. According to Wigand one observes severe circulatory 

 disturbances and falling of temjjerature in animals poisoned by 



