420 



PARASITES OF POULTRY. 



[March 1896. 



PARASITES OF POULTRY. 



(Insects and Mites.) 



The parasitic infestation of poultry causes far more loss than 

 most breeders imagine. Birds are rarely examined, and the 

 cause of their poor condition is not ascertained or even con- 

 sidered. The evil is allowed to spread unmolested, in many 

 instances it spreads with great rapidity, and a general weak 

 and unhealthy condition results. 



These parasites are most injurious to young chicks and 

 " brood " hens. The persistent loss of chicks, and the failure of 

 hens to bring oif their young, are often due to the irritation 

 caused by the presence of parasites upon their bodies — enemies 

 that are frequently unsuspected. These pests weaken the con- 

 stitution and predispose to other maladies, such as diphtheritic 

 roup and " gapes " ; in many cases they have been the forerunner 

 of these worse epizootic diseases. Parasites on the young birds 

 stunt their growth. What is termed " Scaly-leg " is due to a 

 parasite — a mite. Another species of mite at the root of the 

 quills causes birds to pluck their feathers. 



Three Forms of Pests. — There are three distinct groups of 

 pests upon the fowls, namely : — (1.) ¥\esiS (Pulicidce) ; (2.) Lice 

 (Mallophaga) ; and (3.) Mites (Acarina). The two former 

 only are true insects, having the six insect legs ; the Acarina 

 have four pairs of legs and are quite distinct from true insects. 

 The fleas and some of the worst mites are armed with a piercing 

 and sucking mouth ; the bird lice have biting mouths, and thus 

 differ from ticks found on animals. The pests with piercing 

 mouths weaken the birds not only by causing irritation but by 

 actual robbing of blood. The biting lice on the other hand 

 only causejsevere irritation and pruritis, which keep the birds in 

 constant unrest. Most birds have distinct parasites upon them^ 

 each species of louse only flourishing on a particular species 

 of bird ; duck lice, for instance, cannot live permanently upon 

 fowls, and vice versa. 



Diflerent species also seem partial to particular parts of the 

 bird's body. The favourite positions seem to be the head, neck, 

 rump, and under the wings. Some of these parasites live 

 permanently on their hosts (lice and some mites), whilst others 

 (fleas and some mites) go to and fro. Some Acccri live entirely 

 upon, and even under, the skin, deep amongst the feathers and 

 at their roots ; others live like " ticks," with their heads against 

 the skin and their bodies erect ; whilst a single genus (Lipeurus) 

 (Fig. 4) lives between the barbs of the feathers. All these 

 parasites are encouraged by dirt. 



