The association of sub-clinical paratuberculosis with the fertility of Greek dairy ewes and goats varies with parity
Our cross-sectional study investigated the association of sub-clinical Mycobacterium avium subsp. paratuberculosis (MAP) infection with failing to produce a live offspring the season of lambing/kidding (November 2001 to January 20102) before testing (in April-May 2002), in four dairy-sheep and/or goat flocks in Greece (369 animals >= 1.5-year-old). From each selected animal 10 ml of blood and 10 g of feces from the rectum were obtained. The harvested sera were tested for antibodies to MAP with a commercial ELISA test kit; the feces were cultured on Herrold's egg-yolk medium supplemented with mycobactin J and antibiotics. An animal was considered sub-clinically infected when found either seropositive or culture positive. The true prevalence of sub-clinically infected animals, adjusted for the sensitivity and specificity of the parallel testing, was 14% (0.1-28%) and 35.9% (9.2-62.7%) in sheep and goats, respectively. The association of fertility of sheep and goats with sub-clinical paratuberculosis was investigated in random-effects logistic models. Subclinically infected animals (compared to uninfected) had OR for live offspring the previous year of 5.4 for parity < 4, OR = 0.05 for parity > 6, and a non-significant OR for the middle parity category. (c) 2005 Elsevier B.V. All rights reserved.
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Bayesian estimation of sensitivity and specificity of serum ELISA and faecal culture for diagnosis of paratuberculosis in Greek dairy sheep and goats Kostoulas, P.; Leontides, L.; Enoe, C.; Billinis, C.; Florou, M.; Sofia, M. (2006)Latent class models were used to estimate the sensitivity (Se) and the specificity (Sp) of a serum ELISA and a faecal culture (FC) method for the diagnosis of paratuberculosis separately, in sheep and goats. The estimates ...
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