Investigation of an outbreak of besnoitiosis in donkeys in northeastern Pennsylvania

Abstract

Knowledge of clinical and serologic features of besnoitiosis in donkeys will assist clinicians in the diagnosis and prevention of this disease in donkey populations. Besnoitiosis may be an emerging disease of donkeys in the United States.

Serological diagnosis of Besnoitia bennetti infection in donkeys (Equus asinus)

“…This finding has been previously reported in donkeys. 4,9 The potential for recovery from besnoitiosis in infected donkeys is currently unknown, but it is possible that the development of acquired immunity after exposure or infection is a relevant factor in the observed age discrepancy. In contrast to donkeys, seropositivity has been reported to increase with age in cattle.…”

“…3). 1,4,9 Validation of efficient and minimally invasive methods for identifying infected donkeys may strengthen efforts to prevent the spread of besnoitiosis within donkey populations, as infected animals may serve as reservoirs for the parasite, and the introduction of infected animals into naive herds likely plays a role in transmission of infection within herds. 6,10 The aim of the present study was to evaluate the utility of physical examination and 3 serologic assays validated for use in cattle 12 for the detection of B. bennetti infection in donkeys.…”

“…lesions in donkeys. 9 The presence and location of lesions were recorded when observed. Skin biopsies were obtained from all animals identified with lesions suggestive of besnoitiosis and preserved in 10% neutral buffered formalin solution for histologic examination performed by one of the authors (J Peters-Kennedy).…”

Serum Antibodies from a Subset of Horses Positive for Babesia caballi by Competitive Enzyme-Linked Immunosorbent Assay Demonstrate a Protein Recognition Pattern That Is Not Consistent with Infection

“…Some of these proteins have been utilized to develop diagnostic assays to determine infection status (17). Because S. neurona, N. hughesi, and B. bennetti are apicomplexan pathogens that infect equids and have rhoptries as part of their apical complex (20,28,29), it was of interest to determine if cross-reactive antibodies against these organisms might explain the RAP-1-cELISA-positive and immunoblot single-bandingpattern results for U.S. horses (33,34). Despite the failure to demonstrate cross-reactive antibodies against the other apicomplexans in this study, it is still possible that serum antibodies elicited against other organisms by U.S. horses may result in cross-reactivity against the B. caballi RAP-1 protein.…”

“…The N. hughesi-positive horses with neurologic signs had antibody titers ranging from 1:320 to 1:40,960, and S. neurona-positive horses with neurologic signs had antibody titers ranging from 1:320 to 1:5,120. One horse exposed to B. bennetti and three donkeys with a history of clinical besnoitiosis had Besnoitia-specific IFAT antibody titers ranging from 1:200 to 1:3,200 (20).…”