Experimental studies on hookworm infection. I. clinical observations following Ancylostoma caninum infections in dogs

摘要

Eight of the 13, 8 week-old local pups of randomized sexes were divided into 2 respective groups A1 and B1 that were orally and subcutaneously infected at a dose rate of 50 to 200 3~rd stage larvae (L3) per pup per week for 14 consecutive weeks. The 13 pups were treated with Pyrantel pamoate at day 100, rested for 4 days and then given a challenge infection dose of 3, 000 L3 at day 105. Clinical observations on the infected pups included the sub-normal to normal rectal temperature with muscular weakness due to the hemorrhage-induced hypovolemic shock, inappetence, anorexia and vomition resulting from the attendant hypthermia and the intestinal distension by worms. Other signs were the bloody diarrhoea due to enteritis, dehydration, ocular discharge reflecting a secondary bacterial infection of the eyes, some abdominal tissue oedemas due to hypo-albuminaemia, starring hair coat and the expulsion of adult worms reflecting a prevailing type 1 hypersensitivity reaction. These signs in general, were more severe in the group A1 than group B1 pups. There was much clinical improvement at the challenge phase especially in the group B1 pups while the remaining uninfected 5 pups, constituting the control group C1 became most debilitated with the most severe forms of the above signs.