Abstract
Two captive adult agoutis (Dasyprocta mexicana) (cases 1 and 2) died within 1 month with severe flea parasitism, pale carcass with tissue hypoperfusion, severe anemia (case 2), severe centrilobular to submassive hepatocellular necrosis, marked erythroid hyperplasia in the bone marrow (case 2), and severe cardiomegaly and mild heterophilic and lymphoplasmacytic perivascular blepharitis (case 2). Case 3 was an adult agouti that had died 2.5 months before with severe bacterial cellulitis and myositis secondary to a cutaneous penetrating wound associated with fleas, alopecia, crusting, and epidermal hyperplasia and hyperkeratosis with a caudodorsal distribution. At the time of death of case 2, all agoutis were variably parasitized by fleas, and one of three animals had anemia. There were also two agoutis with cutaneous lesions similar to those of case 3 and associated with pruritus and self-mutilation in the same area as the wound of case 3 (flank). Skin biopsies from both animals revealed a perivascular superficial dermatitis with multifocal focal dermal fibrosis and epidermal hyperplasia and hyperkeratosis. All agoutis were anesthetized for manual removal of fleas and were treated with propoxur and selamectin, and they were moved to another facility. Fleas collected from the necropsy cases and live agoutis were classified in the genus Echidnophaga based on the absence of genal and pronotal combs, angular front margin of head, contracted thorax, and the fact that the fleas did not jump.2,6 Furthermore, case 2 had severe infection of the eyelids, a finding typical of Echidnophaga flea infestation in birds. These findings are similar to the effects of fleas on different animal species, particularly camivores.3,7 The deaths of cases 1 and 2 were attributed to hypoxia. Cardiomegaly was a contributing factor to the death of case 2 and was attributed to anemia. The cutaneous disease found in three agoutis is suggestive of flea bite hypersensitivity and secondary self-trauma. To the authors’ knowledge, there are no descriptions of fatal anemia and dermatitis associated with flea ectoparasitism in any rodent species, although rodents are commonly infected with different flea species, including Echidnophaga.1 Fleas and rodents are important in the transmission of relevant infectious diseases such as plague (Yersinia pestis) and tularemia (Francisella tularensis).1,3-5
Literature Cited
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