88 
Parasites of Cattle and Sheep. 
though the brain were affected. We have witnessed on rare 
occasions considerable losses through inflammation of the lungs, 
and have found larvae in the windpipe, and considerable 
quantities of purulent matter there and in the bronchial tubes. 
Fortunately the CEstrus of the sheep is not a very common 
species. 
Prevention. — The preventive treatment, which must- be 
carried out during the summer, consists of application to the 
nostril and face of sheep in districts where the fly is known to 
exist, of some substance distasteful to the fly, in order to prevent 
it from depositing its eggs or larvae, or of killing them. For this 
purpose the material spoken of as deterrent to the ox warble 
fly of cattle is applicable. Probably smearing the nostrils, &c., 
with tar is most effective and enduring. All practical means 
should be adopted for killing the larvae as they leave the nostril 
in May or June. 
Parasitic Gastritis. — The abomasum, or true stomach of the 
sheep, like that of the ox, may be infested with parasites of 
various species. The Strongylus contortus , a slender round 
worm, about one to one and a half inches in length, has for 
many years been recognised as the cause of inflammation of the 
lining membrane of the abomasum. It is frequently found 
in the company of other nematode worms, especially minute 
strongyles, and formerly it was taken for granted that the 
smaller worms were the young of the larger. Later microscopic 
search has demonstrated that the smaller worms are of a quite 
distinct species, to which the name Strongylus cervicornis has 
been given. The worms are found separately or together, 
inducing the disease under review. This smaller strongyle is 
usually from to in. in length, the females being longer and 
more numerous than the males. Though liable to escape 
observation in the stomach or its contents, it may be readily 
discerned by means described when referring to the small 
strongyles of the stomach of the ox. Though round worms of 
other species are known to inhabit the stomach of the sheep, 
they are rarely found in large numbers in this country, and 
are not credited with the production of appreciable disease. 
Nothing is known as to the life-history and development of 
these strongyles except that the adult female is seen to contain 
many eggs, and that on examination of scrapings of an affected 
stomach only worms and eggs are found. 
These parasites are responsible for very serious and exten- 
sive losses, especially of lambs, though occasionally adults may 
be affected. The disease dependent on their attack is common 
and widespread. Though it claims a large number of victims 
every year, in some seasons and in some districts it, appears as 
a veritable scourge. A few years since, the disease was so 
