Ancylostoma braziliense

Ancylostoma braziliense

<p align="CENTER"><span style="font-size: medium;"><i><b>Ancylostoma</b></i></span><span style="font-size: medium;"><i><b>braziliense</b></i></span><span style="font-size: medium;"><b> de Faria, 1910</b></span></p> <p align="JUSTIFY"><span style="font-size: medium;"><b>ETYMOLOGY:</b></span><span style="font-size: medium;"><i>Ancylo</i></span><span style="font-size: medium;"> = curved + </span><span style="font-size: medium;"><i>stoma</i></span><span style="font-size: medium;"> = mouth; </span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> for the geographical location where the worms were first found.</span></p> <p align="JUSTIFY"><span style="font-size: medium;"><b>SYNONYMS:</b></span><span style="font-size: medium;"><i>Agchylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span></p> <p align="JUSTIFY"><span style="font-size: medium;"><b>HISTORY:</b></span><span style="font-size: medium;"> This worm was described in 1910 by Dr. Gomes de Faria from specimens recovered from the intestines of cats and dogs. It was later decided that this species was synonymous with </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>ceylanicum</i></span><span style="font-size: medium;"> which had been found in cats, dogs, and people in Asia (Lane, 1922; Leiper, 1913). Biocca (1951) redescribed both species and presented convincing evidence that the species were different. Similarly, Beaver (1956) discussed the fact that there had been no confirmed human infections with </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> in the United States where it was the only one of these two species present. More recently Rep et al. (1968) and Rep (1972) have further proven that these are separate species by performing single-sex cross-over experiments in dogs. However, there is a period of about 50 years when the majority of workers thought that these were identical forms; thus, it is difficult to examine earlier reports relative to the geographical distribution of these two parasites.</span></p> <p align="JUSTIFY"><span style="font-size: medium;"><b>GEOGRAPHIC DISTRIBUTION:</b></span><span style="font-size: medium;"> It would appear that </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> represents an American or African form of the </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>ceylanicum</i></span><span style="font-size: medium;"> hookworm of Asia. Biocca (1951) only identified specimens of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> from Africa and South America. This worm has also been reported from Central and North America. Yoshida et al. (1974) reported that it appears in Japan, and there have been additional reports of mixed infections in cats with </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> and </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>ceylanicum</i></span><span style="font-size: medium;"> in Indonesia (Soeripto et al., 1978) and Malaysia (Amin-Babjee, 1978; Yoshida et al., 1973). </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> appears to prefer coastal areas, at least in the Americas, hence the prevalence of this parasite tends to drop as one moves inland. It is possible that </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziense</i></span><span style="font-size: medium;"> has higher requirements for sandy conditions or can withstand more readily the higher levels of salt found in coastal soils.</span></p> <p align="JUSTIFY"><span style="font-size: medium;"><b>LOCATION IN HOST:</b></span><span style="font-size: medium;"> The adults are found within the anterior small intestine of the feline host. It appears that larvae are capable of persisting in the tissues of the feline host, but this has not been examined in any detail.</span></p> <p align="JUSTIFY"><span style="font-size: medium;"><b>PARASITE IDENTIFICATION:</b></span><span style="font-size: medium;"> The adults of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> are 4 to 10.5 mm long. Members of the genus </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"> can be distinguished from </span><span style="font-size: medium;"><i>Uncinaria</i></span><span style="font-size: medium;"> by determining whether or not there are ventral teeth in the buccal capsule. Specimens of </span><span style="font-size: medium;"><i>Ancylstoma</i></span><span style="font-size: medium;"> have large teeth within the buccal capsule while specimens of </span><span style="font-size: medium;"><i>Uncinaria</i></span><span style="font-size: medium;"> are recognized by the presence of cutting plates. The adults of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>brazilinese</i></span><span style="font-size: medium;"> and </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>ceylanicum</i></span><span style="font-size: medium;"> possess only two teeth on the ventral aspect of the buccal cavity with the lateral tooth being large and the median tooth quite small. The adults of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>tubaeforme</i></span><span style="font-size: medium;"> have three teeth on each side of the buccal capsule. </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> can be differentiated from </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>ceylanicum</i></span><span style="font-size: medium;"> by careful examination of the teeth within the buccal cavity. The medial teeth are smaller in </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> then they are in </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>ceylanicum</i></span><span style="font-size: medium;">. Another means of separating these two species is by careful examination of the copulatory bursa of the male. The lateral lobes of the bursa are relatively shorter in </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>ceylanicum</i></span><span style="font-size: medium;"> than they are in </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> and the branching of the externo-dorsal rays occurs more posteriad in </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>ceylanicum</i></span><span style="font-size: medium;"> than it does in </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>brasiliense</i></span><span style="font-size: medium;">. Finally, Yoshida (1971a) showed that if the adults are killed in hot water (149</span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">F or 65</span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;"> C) prior to fixation that about 90% of the females of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> are noted to have a distinct 20 degree bend in the body at the level of the vulva (about two-thirds back on the body from the anterior end). This bend does not occur with </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>ceylanicum</i></span><span style="font-size: medium;"> adults.</span></p> <p align="JUSTIFY"><span style="font-size: medium;"> The eggs of the different </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"> species found in the cat are apparently indistinguishable from each other. The eggs of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> are considered by most workers (e.g., Sarles, 1929) to be slightly smaller (55 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">m x 34 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">m) than those of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>caninum</i></span><span style="font-size: medium;"> (62 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">m x 38 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">m). The eggs of </span><span style="font-size: medium;"><i>Uncinaria</i></span><span style="font-size: medium;"> are considered larger than those of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"> being 70 to 90 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">m long by 40 to 50 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">m wide. The two eggs are easy to distinguish in mixed infections (Ehrenford, 1953).</span></p> <p align="JUSTIFY"><span style="font-size: medium;"> Yoshida (1971b) showed that the infective-stage larvae of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>brazilinese</i></span><span style="font-size: medium;"> average 662 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">m in length, which made them recognizably shorter than the larvae of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>ceylanicum</i></span><span style="font-size: medium;"> which averaged 712 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">m in length. The larvae of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> are thus slightly longer than the larvae of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>caninum</i></span><span style="font-size: medium;"> which average 630 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">m in length (Lucker, 1942) and slightly longer than the larvae of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>tubaeforme</i></span><span style="font-size: medium;"> that have been reported to be 630 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">m long (Okoshi and Murata, 1967). The infective-stage larvae of the </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"> species are all longer than the larvae of </span><span style="font-size: medium;"><i>Uncinaria</i></span><span style="font-size: medium;"><i>stenocephala</i></span><span style="font-size: medium;"> which measure only 500 to 580 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">m in length. Thus, ranking the infective-stage larvae of the four major feline hookworms there is </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>ceylanicum</i></span><span style="font-size: medium;"> (712 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">m), </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> (660 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">m), </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>tubaeforme</i></span><span style="font-size: medium;"> (630 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">m), and </span><span style="font-size: medium;"><i>Uncinaria</i></span><span style="font-size: medium;"><i>stenocephala</i></span><span style="font-size: medium;"> (&lt;600 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">m). </span></p> <p align="JUSTIFY"><span style="font-size: medium;"><b>LIFE CYCLE:</b></span><span style="font-size: medium;"> Cats can be infected by the ingestion of larvae or by the larvae penetrating the skin. When cats are infected orally with third-stage larvae, these infective larvae enter the intestine mucosa. Within the mucosa, these larvae develop to the fourth stage. The larvae then appear in the intestinal lumen after the second day of infection. The prepatent period of the infection in cats following oral infection is 14 to 16 days. If cats are infected through the skin, the larvae migrate via the bloodstream to the lungs, migrate up the trachea, and are then swallowed. When the larvae reach the small intestine, most are still young third -stage larvae. The prepatent period following percutaneous infection can be 13 to 27 days (Dove, 1932).</span></p> <p align="JUSTIFY"><span style="font-size: medium;"> Cats can also be infected by the ingestion of paratenic hosts. In mice after oral or percutaneous infection, the larvae migrate via the bloodstream to the lungs and then proceed to the area of the head of the mouse, where they persist for up to 18 months. In mice, most larvae are found within salivary glands or within the nasopharyngeal epithelium (Norris, 1973). Cats have been experimentally infected by feeding them larvae recovered from infected mice (Norris, 1971). </span></p> <p align="JUSTIFY"><span style="font-size: medium;"> On the basis of a single trial, it would appear that transplacental and transmammary transmission of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> does not occur in dogs (Miller, 1971). This has not been examined in the cat.</span></p> <p align="JUSTIFY"><span style="font-size: medium;"> The aults of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> have been reported to live about four to eight months (Sarles, 1929). A single female worm produces between 200 to 6000 eggs per day (Sarles, 1929). As the infection matures, the number of eggs produced by a single female will decline. The infection of younger cats can be more easily obtained than the infection of older cats (Sarles, 1923).</span></p> <p align="JUSTIFY"><span style="font-size: medium;"><b>CLINICAL PRESENTATION AND PATHOGENESIS:</b></span><span style="font-size: medium;"> When </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> was orignally described, it was noted that this hookworm was not as pathogenic as </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>caninum</i></span><span style="font-size: medium;"> (Gomes de Faria, 1910). Very little hemorrhage occurs at the site of larval development or adult attachment. Using </span>^{<span style="font-size: medium;">51</span>}<span style="font-size: medium;">Chromiaum-labelled erythrocytes, it has been shown that the blood loss due to infections of adult worms in kittens is about 1 to 2 ul of blood/worm/day (Miller, 1966). Blood loss was first detected in cats 10 days after infection, and the experimentally infected kittens maintained hemoglobin levels, hematocrit values, and weight gains that were comparable to uninfected age-matched control kittens.</span></p> <p align="JUSTIFY"><span style="font-size: medium;"><b>TREATMENT:</b></span><span style="font-size: medium;"> Products approved for the treatment of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> by oral administration include (Bowman, 1992): toluene (in a dichlorophen-toluene mixture with a dose of 264.5 mg toluene per kilogram body weight), dichlorvos (11.1 mg/kg), febantel (as a febantel-proaziquantel mixture; 10 mg/kg BW febantel for adult cats and 15 mg/kg BW febantel for kittens), and n-Butyl chloride (400 mg/kg). Ivermectin as a chewable product (administered at 24 </span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">g/kg) that is to be administered monthly is reported to reduce infections by 98.1% as compared to untreated controls (Nolan et al., 1992). Disophenol sodium is approved at 10 mg/kg in a formulation that is to be administered subcutaneously.</span></p> <p align="JUSTIFY"><span style="font-size: medium;"><b>EPIZOOTIOLOGY:</b></span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> is a parasite that is most commonly found in coastal areas with sandy soils. The development of the infective-stage larva has been shown to undergo optimal development at 27</span><span style="font-family: 'WP MathA';"><span style="font-size: medium;"></span></span><span style="font-size: medium;">C (Rep, 1965). There has been little examination of the effects of salinity on the development of the infective larvae of this hookworm, but one would suspect that the larvae can develop in rather high salt concentrations. It is also likely that these worms do not develop well in areas where there are freezing temperatures that occur for extended periods.</span></p> <p align="JUSTIFY"><span style="font-size: medium;"><b>HAZARD TO OTHER ANIMALS:</b></span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> is a parasite that is capable of infecting dogs as well as cats. It is also highly likely that if the conditions are appropriate for the development of the larvae, that tey could infect small mammals that share ground with the infected cat. There has been almost no attention given to the actual disease caused in rodent hosts.</span></p> <p align="JUSTIFY"><span style="font-size: medium;"><b>HAZARD TO HUMANS</b></span><span style="font-size: medium;"><i>:</i></span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> is probably the major cause of human cases of cutaneous larva migrans. That this was the major cause of hookworm induced cutaneous larva migrans in the United states was shown clearly by Dove (1932). Cases of cutaneous larva migrans continue to be not uncommon, especially in travelers who have visited the Carribean (Davies et al., 1993). Occasionally, cases of creeping eruption are reported from unusual temperate locations (Klose et al., 1996). In some instances, the large numbers of larvae that enter an individual will undergo the initial portion of a somatic migration and cause severe pneumonitis that might require hospitalization (Beaver et al., 1984).</span></p> <p align="JUSTIFY"><span style="font-size: medium;"><b>CONTROL/PREVENTION:</b></span><span style="font-size: medium;"> Cats are being infected by the ingestion of larvae when eating grass or grooming, by larvae penetrating the skin, or the ingestion of larvae in paratenic hosts. Thus, whenever cats are in an endemic area and have access to the outside, they are probably at risk of contracting this infection. The recent availability of a monthly heartworm preventative that is also capable of treating adult hookworm infections will make it possible to protect cats from infections with this parasite.</span></p> <p align="JUSTIFY"><span style="font-size: medium;"><b>REFERENCES:</b></span></p> <p align="JUSTIFY"><span style="font-size: medium;">Amin-Babjee. 1978. Parasites of the domestic cat in Selangor, Malaysia. Kajian Veterinar 10:107-114.</span></p> <p align="JUSTIFY"><span style="font-size: medium;">Beaver PC. 1956. The record of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> as an intestinal parasite of man in North America. Am J Trop Med Hyg 5:737-789,</span></p> <p align="JUSTIFY"><span style="font-size: medium;">Biocca E. 1951. On </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> (de Faria, 1910) and its morphological differentiation from </span><span style="font-size: medium;"><i>A. ceylanicum</i></span><span style="font-size: medium;"> (Looss, 1911). J Helminthol 25:1-10.</span></p> <p align="JUSTIFY"><span style="font-size: medium;">Bowman DD. 1992. Hookworm parasites of dogs and cats. Comp Cont Ed Pract Vet 14:585-595.</span></p> <p align="JUSTIFY"><span style="font-size: medium;">Dove WE. 1932. Further studes of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> and the etiology of creeping eruption. Am J Hyg 15:664-711.</span></p> <p align="JUSTIFY"><span style="font-size: medium;">Ehrenford FA. 1953. Differentiation of the ova of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>caninum</i></span><span style="font-size: medium;"> and </span><span style="font-size: medium;"><i>Uncinaria</i></span><span style="font-size: medium;"><i>stenocephala</i></span><span style="font-size: medium;"> in dogs. Am J Vet Res 14:578-580.</span></p> <p align="JUSTIFY"><span style="font-size: medium;">Gomes de Faria J. 1910. Contribuição para a sistematic helmitolojioca braziliera. 3. </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> n. sp. parazito dos gatos e cãis. Mem Ist Oswaldo Cruz 2:286-293.</span></p> <p align="JUSTIFY"><span style="font-size: medium;">Lane C. 1922. </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;">. Ann Trop Med Parasitol 16:347-352.</span></p> <p align="JUSTIFY"><span style="font-size: medium;">Leiper RT. 1913. The apparent identity of </span><span style="font-size: medium;"><i>Agchylostoma</i></span><span style="font-size: medium;"><i>ceylanicum</i></span><span style="font-size: medium;"> (Looss, 1911) and Agchylo</span><span style="font-size: medium;"><i>s</i></span><span style="font-size: medium;">toma </span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> (Faria, 1910). J Trop Med Hyg 16:334-335.</span></p> <p align="JUSTIFY"><span style="font-size: medium;">Lucker JT. 1942. The dog </span><span style="font-size: medium;"><i>Strongyloides</i></span><span style="font-size: medium;"> with special reference to occurrence and diagnosis of infections with the parasite. Vet Med 37:128-137.</span></p> <p align="JUSTIFY"><span style="font-size: medium;">Miller TA. 1966. Blood loss during hookworm infection, determined by erythrocyte labeling with radioactive </span>^{<span style="font-size: medium;">51</span>}<span style="font-size: medium;">Chromium. II. Pathogenesis of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> infection in dogs and cats. J Parasitol 52:856-865.</span></p> <p align="JUSTIFY"><span style="font-size: medium;">Miller TA. 1971. Vaccination against the canine hookworm diseases. Adv Parasitol 9:153-183.</span></p> <p align="JUSTIFY"><span style="font-size: medium;">Nolan TJ, Niamatali S, Bhopale V, Longhofer SL, Schad GA. 1992. Efficacy of a chewable formulation of ivermectin against a mixed infection of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> and </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>tubaeforme</i></span><span style="font-size: medium;"> in cats. Am J Vet Res 53: 1411-1413</span></p> <p align="JUSTIFY"><span style="font-size: medium;">Norris DE. 1971. The migratory behavior of the infective-stage larvae of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>braziliense</i></span><span style="font-size: medium;"> and </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"><i>tubaeforme</i></span><span style="font-size: medium;"> in rodent paratenic hosts. J Parasitol 57:998-1009.</span></p> <p align="JUSTIFY"><span style="font-size: medium;">Norris DE. 1973. Migratory behavior of infective stage larvae of </span><span style="font-size: medium;"><i>Ancylostoma</i></span><span style="font-size: medium;"> species in rodent paratenic hosts (abstr). Proc 9th Int Cong Trop Med Malaria 1:175-176.</span></p> <p align="JUSTIFY"><span style="font-size: medium;">Okoshi S, Murata Y. 1967a. Experimental studies on ancylostomiasis in cats. II. 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