Aspectos epidemiológicos da epididimite em pequenos ruminantes: isolamento, caracterização molecular e diagnóstico diferencial.

Abstract

This thesis is composed by three Chapters. In Chapters I, the study was conducted experimental infection in two goats (animals 1 and 2) and two sheep (animals 3 and 4) with an Actinobacillus seminis strain isolated from goat in Brazil. Samples of semen, puncture and fragments of epididymis, deferent duct, testicles and seminal vesicles were used, and histopathological, microbiological culture and molecular diagnoses were performed. At clinical evaluation it were found unilateral swelling of firm consistency after 30 days in epididymis and testicle from animal 4 that continued until the day of euthanasia, as well as animal 1 shown discrete unilateral swelling of testicles. Gross and microscopic lesions in animals 3 and 4 were compatibles with that caused by A. seminis infection. A. seminis was isolated from material of puncture, testicle fragment and semen of one sheep (animal 4). In Chapter II, the objective of experimentally evaluate the pathogenicity of an isolate named SAAS01 in 15 goats. The animals were clinically analyzed over a 12-week period, during which time semen collections were performed by electroejaculation, and the scrotal diameter was measured every 20 days. These animals were challenged with 2 mL of a suspension containing 1.2 x 10⁹ CFU/mL of A. seminis (SAAS01 isolate)16 by the following routes: intrapreputial, cauda epididymis, and conjunctival. In the clinical evaluation, a unilateral increase in firm consistency can be observed in the epididymides and testes of animals 18, 51, and 57 after 30 days; this firmness continued until the day of euthanasia. Animals 51 and 57 presented histopathological findings with macroscopically and microscopically significant changes. The isolation of small (1 to 2 mm), smooth, shiny, and pigment-free colonies was possible from the semen material collected from animals 18, 51, and 57 in the third and fourth collections. DNA of A. seminis was amplified from the semen of animals 00, 12, 18, 22, 51 and 57, and from testicular fragments from animals 12 and 57. In Chapter III, the objective of this work was to select samples from seropositive sheep in the AGIDA test, both sexes, and from several states of the Northeast (PI, CE, SE, PB, RN), of which 130 were from Embrapa Goat and Sheep serum bank (N = 2465 sheep) and 41 from the sera bank of the Laboratory of Communicable Diseases of the CSTR / UFCG (n = 1134 sheep), totaling 171 positive sheep, and compared with the Complement Fixation test (FC) and competition ELISA. In the FC test, no positive serology was observed, while in the ELISA-i four animals (2.33%) were seropositive and 20 animals (11.69%) suspected.