Abstract
ABSTRACT. Galvão A., Peixoto T.C., Almeida J., & Sanavria A. [Evaluation of reproductive performance in Nelore bulls experimentally infested with Dermatobia hominis (Linnaeus Jr., 1781) larvae in the scrotum]. Avaliação da eficiência reprodutiva de touros da raça Nelore, experimentalmente infestados por larvas de Dermatobia hominis (Linnaeus Jr.) na bolsa escrotal. Revista Brasileira de Medicina Veterinária, 32(3):172- 177, 2010. Curso de Pós-Graduação em Medicina Veterinária, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, BR 465, Km 7, Seropédica, 23890-000, RJ, Brasil. E-mail: tandyvet@gmail.com Dermatobia hominis affects bovines causing serious economic and productivity damages for beef cattle due to low milk and beef production, delay in animals growth and death of calves. Besides, it has related that natural occurrence of dermatobiosis in bull´s scrotum results in less reproductive efficiency. That happens because of local inflammation what increases the scrotum temperature. The occurrence of dermatobiosis and alteration in bulls fertility has been studied with intention to evaluate its influence on the parameters of spermatic quality, such as, testicular perimeter and physical characteristics as motility, turbidity, intensity and spermatic concentration, morphology of the semen. 18 bulls of the commercial Nelore breed had been used, with age of 36 months, variation of corporal score of 6.0 to 6.5, after pre selection, following the standard of the Manual of the CBRA. The bulls had been placed in two groups: G1 (nine infested with D. hominis larvae on the scrotal skin) and G2 (nine bulls as controls). They were submitted to andrologic examinations in days D24, D48, D63 and D74, and testicular, and seminal characteristics were evaluated. Data obtained had been analyzed by the variance test. Results indicate that they did not have significant difference (P<0.005). So it is concluded that experimental infestation of D. hominis in the scrotal skin did not influence the spermatic quality of bulls of the Nelore breed.