title: 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.
authors.affiliation: Department of Animal Sciences, Federal Rural University of the Semiarid (UFERSA), Av. Francisco Mota, Br 110, Km 47-59, 59625-900, Mossoró, Rio Grande do Norte, Brazil. jaelsoares@hotmail.com
authors.forename: Jael S
authors.initials: JS
authors.lastname: Batista
authors.forename: Carla M F
authors.initials: CM
authors.lastname: Rodrigues
authors.forename: Roberio G
authors.initials: RG
authors.lastname: Olinda
authors.forename: Taciana M F
authors.initials: TM
authors.lastname: Silva
authors.forename: Rodolfo G
authors.initials: RG
authors.lastname: Vale
authors.forename: Antônio C L
authors.initials: AC
authors.lastname: Câmara
authors.forename: Rachiel E S
authors.initials: RE
authors.lastname: Rebouças
authors.forename: Francisco Silvestre B
authors.initials: FS
authors.lastname: Bezerra
authors.forename: Herakles A
authors.initials: HA
authors.lastname: García
authors.forename: Marta M G
authors.initials: MM
authors.lastname: Teixeira
mesh_terms: D000818:Animals; D000981:Antiprotozoal Agents / Q000008:administration & dosage; D001938:Brazil / Q000453:epidemiology; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000469:parasitology* / Q000473:pathology / Q000635:transmission; D004133:Diminazene / Q000008:administration & dosage / Q000031:analogs & derivatives; D018445:Infectious Disease Transmission, Vertical; D018512:Parasitemia / Q000453:epidemiology / Q000469:parasitology / Q000473:pathology; D015995:Prevalence; D012720:Severity of Illness Index; D016019:Survival Analysis; D016689:Trypanosoma vivax / Q000302:isolation & purification*; D014353:Trypanosomiasis, African / Q000453:epidemiology / Q000473:pathology / Q000635:transmission / Q000662:veterinary*
chemical_list: D000981:Antiprotozoal Agents; C003915:diminazene aceturate; D004133:Diminazene