Shade availability on pasture does not affect semen characteristics of Brahman bulls (Bos taurus indicus)


environment, heat stress, thermotolerance, breeding soundness evaluation, zebu. chave: ambiente, estresse por calor, termotolerância, avaliação reprodutiva, zebu.

How to Cite

Neto, P. F., Geraldo , A. C. A. P. de M., dos Santos, T. M. da C. L., Vilela, R. A., Tribucci, A. M. de O., de Andrade, A. F. C., Arruda, R. P., & Titto, E. A. L. (2021). Shade availability on pasture does not affect semen characteristics of Brahman bulls (Bos taurus indicus). Brazilian Journal of Veterinary Medicine, 43(1), e003721.


Testicular degeneration by heat is the leading cause of infertility in bulls. Beef cattle are generally farmed under hot and humid conditions, and consequently, the thermotolerance of each breed must be considered in their natural environment. This study aimed to evaluate the reproductive characteristics of Brahman bulls maintained in the grazing system, with or without shadow availability. Ten Brahman bulls aging between 24 and 30 months were allocated in two different paddocks, with or without shadow availability. The heat tolerance test was performed on three non-consecutive typical summer days. The semen samples were collected at four times points in a 14 days interval. The climate conditions were monitored throughout the experiment; and clinical evaluation, testicular consistence and scrotal circumference were measured before every semen collection. In addition, semen was evaluated regarding volume, aspect, turbulence, motility, straight movement, sperm concentration, and morphological exam. The studied Brahman bulls showed a high thermolysis capacity, high heat tolerance, and no differences in semen quality were observed between groups.


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Copyright (c) 2021 Paulo Fantinato Neto, Ana Carina Alves Pereira de Mira Geraldo , Thais Mayra da Cunha Leme dos Santos, Reíssa Alves Vilela, Adriana Moraes de Oliveira Tribucci, André Furugen Cesar de Andrade, Rubens Paes Arruda, Evado Antonio Lencioni Titto