Highly debilitating natural Trypanosoma vivax infections in Brazilian calves: epidemiology, pathology, and probable transplacental transmission

Abstract

Clinical, epidemiological, and pathological aspects of trypanosomiasis caused by Trypanosoma vivax in calves were reported for the first time in northeast Brazil. Clinical and epidemiological data, packed cell volumes (PCV), and parasitemia were assessed in 150 calves in May 2009 (rainy season-survey 1) and in 153 calves in November 2009 (dry season-survey 2) in three farms (A, B, and C). Prevalence of T. vivax in calves examined in the survey 1 was 63.3%, 65.0%, and 80.0% in farms A, B, and C, respectively. Morbidity varied from 63.3% to 80%, mortality from 15% to 30% and lethality from 23% to 37.5%. In survey 1, for all farms, high parasitemia (from 30.3 to 26.2 × 10(6) parasites/mL), fever (from 39.8 to 40.3°C), low PCV (from 15.7% to 18.1%), and body score (from 2.5 to 3.5) were detected. Calves showed depression, weight loss, pale mucous membranes, enlarged lymph nodes, edema of the dewlap, cough, coryza, and diarrhea. The animals from farms A and B were treated with diminazene aceturate. Six months after, in survey 2, non-treated calves from farm C showed values for prevalence (81.82), morbidity (81.82), mortality (12.73), and lethality (15.55) similar to those in survey 1 (P > 0.05). Also in survey 2, four calves aging merely 1-3 days old presented high parasitemia levels (from 32 × 10(6) to 74 × 10(6) parasites/mL), suggesting transplacental transmission. In conclusion, trypanosomiasis by T. vivax constitutes high prevalent disease for calves raised in Brazilian semiarid and may have transplacental transmission.

A New PCR-RFLP for Species-Specific Diagnosis of South American Animal Trypanosomiasis

“…In terms of clinical presentation, infected cattle presented a range of hematological and clinical signs varying from completely asymptomatic to severe hematologic alterations or death. These findings are in agreement with previous reports (Osório et al, 2008;Batista et al, 2012). Nevertheless, the chronic infection was found to be associated with pale mucous membranes, progressive weight loss, diminished body condition score, lymphadenitis and thrombocytopenia.…”

Risk factors for trypanosomiasis by Trypanosoma vivax in cattle raised in Rio Grande do Norte state

“…Among the authors investigating trypanosomiasis in cattle caused by T. vivax in Latin America, it can be seen that the occurrence of the outbreaks coincides with the increase in the density of flocks and flies of the stables, occurring during the rainy season (OTTE; ABUABARA, 1991;SILVA et al, 1996;BATISTA et al, 2012).…”

Bovine Trypanosomiasis: Retrospective Investigation and Clinical Signs

“…1,2 In West Africa, T. vivax is an important and pathogenic trypanosome in cattle, being a significant disease to animal breeding transmitted by the tsetse fly (Glossina spp). In Latin America, mechanical vectors transmit the parasite.…”