Helminth Survey of Dogs and Cats in New Jersey

Abstract

Single fecal examinations, using the zinc sulfate flotation technique, were performed on 4,217 animals (2,737 dogs and 1,480 cats) and 3,730 helminth infections were revealed. Of these animals, 685 dogs and 318 cats were treated and necropsied, thus uncovering 584 additional infections not found by flotation. About 55% of the additional infections were tapeworms, and the remaining 45% were nematodes, of which 22% were light infections, 17% were immature, and 6% consisted of male worms only. In recent years there have been a number of surveys of helminths of dogs and cats, including one from this laboratory (Burrows and Lillis, 1960). Since many surveys are based on single fecal examinations and since additional species are often found in those animals that are necropsied, it appeared that many surveys probably fail to reveal a fair percentage of infections harbored. To determine this, a detailed study was made of records of stool examinations, treatment results, and necropsies of dogs and cats used in this laboratory from 1 April 1960, the end period of the previous report (Burrows and Lillis, 1960), through 31 October 1966. MATERIALS AND METHODS The animals were strays, supplied by a regular dealer who obtained them from central New Jersey, the same general area as in earlier reports of other infections (Lillis and Burrows, 1964; Lillis, 1964; Burrows and Lillis, 1965, 1967). The animals were housed in individual cages and remained at the laboratory only a few days to a few weeks, so there was no opportunity to acquire an infection while at the laboratory. Stool examinations were performed shortly after receipt of the animals, using the zinc sulfate flotation technique (sp. gr. 1.2). The strong solution was used because it will float heavier eggs, such as Taenia (Burrows, 1965). All helminth eggs and larvae found by flotation were identified and recorded. Data from the necropsy of dogs and cats were obtained during routine anthelmintic screening trials. These animals were known to be infected with certain parasites, as found on flotation, and were used in chemotherapeutic trials of experimental compounds. A stainless steel pan was placed in the bottom of each cage and all feces passed were collected and examined for worms Received for publication 10 April 1967. * Present address: CIBA Research Farm, Three Bridges, New Jersey 08887. present. The specimens were washed in a 40-mesh sieve and the sieve contents examined, a little at a time, in a black-bottomed pan for worms passed. At necropsy, the small intestine was examined carefully for worms remaining. The worm burden of an animal was the sum of the worms passed plus those remaining at necropsy. Since numerous animals were given compounds that did have anthelmintic activity, many worms passed out in a disintegrated condition, and sex, species, and degree of maturity could not always be determined. For some animals, no worms could be recovered at all, as a result of disintegration and in this case, the intensity of the infection was considered light, and in the range of from one to 10 worms. Infections of hookworm and whipworm in dogs and hookworm and ascarids in cats, that fell in various ranges, were counted to demonstrate the intensity of the worm burdens in the necropsied animals.