Caracterização epidemiológica e fatores de risco associados às lentiviroses, brucelose e leptospirose de caprinos e ovinos comercializados em feira de animais na Região do Semiárido Nordestino.

Abstract

The northeasten semiarid region concentrates the majority of the goat and wooless sheep herds of Brazil, with 8,5 millions of goats and 9,9 millions of sheep, and live animal fairs commonly take place in the referred region, and it is where the farmers generally commercialize their production. Agglomeration of animals is an important link in the transmission of infectious diseases, resulting in the importance of the knowledge about the epidemiology of diseases of the small ruminants. Therefore, the objective of this study was to determine the frequency of the anti-Small Ruminants Lentivirus (SRLV), anti- Leptospira sp. and anti-Brucella ovis antibodies in goats and sheep commercialized in the animal fair of the municipality of Tabira - PE, in the Brazilian semiarid, as well as the identification of the possible risk factors for diseases. Serum samples were collected from 233 crossbred goats and 119 crossbred sheep, belonging to twelve farmers, in the animal fair of the municipality between November 2014 and June 2015. An epidemiological questionnaire was applied for the analysis of the risk factors. The variables obtained were submitted to univariate and multivariate analysis. The diagnosis of infection by SRLV was performed by the techniques of agar gel immuno-diffusion (AGID) and Western Blotting (WB). One seropositive goat was detected by the AGID positivity was not detected for sheep. By the WB, 15/233 (6.44% CI95% = 3.94 – 10.35%) goats and 8/119 (6.72% IC95% = 3.45 – 12.71%) sheep were seropositive, totalizing 23/352 (6.53% CI95% = 4.39 – 9.61%) reagent animals. The twelve studied herds presented seropositive animals. To annually vermifuge the animals (odds ratio = 5.9; p = 0.04) was considered to be a risk factor for disease in goats. Risk factors for the infection in sheep were not identified. The WB technique presented greater sensitivity than the AGID, in demonstrating the occurrence of the SRLV in goats and sheep in the animal fair. The diagnosis of Leptospira spp. was performed by microscopic agglutination test (MAT). 16/233 (6.87% CI95% = 4.27 – 10.83%) seropositive goats and 16/119 (13.45% CI95% = 8.67 – 21.24%) seropositive sheep. The most frequent serotype was the Icterohaemorrhagiae. The sampled herds of goats and sheep presented seropositivity in 44.5% (4/9) and 62.5% (5/8), respectively. The intensive livestock farming system (odds ratio = 15.8; p < 0.001) and the rearing in conjunction with equines (odds ratio = 7.3; p = 0.005), were considered to be risk factors for the disease in goats. Risk factors for the disease in sheep were not identified. The infection by Leptospira spp. is present in the studied small ruminants. The seropositivity for B. ovis was tested in sheep by the AGID technique. The frequency of seropositive was of 7/119 (5.88% CI95% = 2.88 – 11.65%), occurring in females belonging to three farmers. The intensive livestock farming system was considered to be a risk factor for infection (odds ratio = 11.5; p = 0.005). Measures aimed at the control of the transit and agglomerations, which enable the increase of the diagnosis of the disease in small ruminants which take part in these events, as well as improvements in the hygiene and sanitary conditions of the properties, are recommended, aiming to reduce the risk of transmission of the infection to those vulnerable.