title: The association of sub-clinical paratuberculosis with the fertility of Greek dairy ewes and goats varies with parity.
abstract: 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 2002) before testing (in April-May 2002), in four dairy-sheep and/or goat flocks in Greece (369 animals >or=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. Sub-clinically 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.
authors.affiliation: Laboratory of Epidemiology, Biostatistics and Animal Health Economics, School of Veterinary Medicine, University of Thessaly, 224 Trikalon st., 43100 Karditsa, Greece. pkost@vet.uth.gr
authors.forename: P
authors.initials: P
authors.lastname: Kostoulas
authors.forename: L
authors.initials: L
authors.lastname: Leontides
authors.forename: C
authors.initials: C
authors.lastname: Billinis
authors.forename: G S
authors.initials: GS
authors.lastname: Amiridis
authors.forename: M
authors.initials: M
authors.lastname: Florou
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005243:Feces / Q000382:microbiology; D005260:Female; D015511:Goat Diseases / Q000453:epidemiology / Q000209:etiology*; D006041:Goats; D006115:Greece / Q000453:epidemiology; D007247:Infertility, Female / Q000453:epidemiology / Q000209:etiology / Q000662:veterinary*; D008297:Male; D016927:Mycobacterium avium subsp. paratuberculosis / Q000276:immunology / Q000302:isolation & purification; D010283:Paratuberculosis / Q000150:complications* / Q000453:epidemiology; D010298:Parity; D011247:Pregnancy; D015995:Prevalence; D018401:Sample Size; D012756:Sheep; D012757:Sheep Diseases / Q000453:epidemiology / Q000209:etiology*
chemical_list: D000907:Antibodies, Bacterial