Resumo

VALLE, A; FUENTES, A  e  PUERTA, M. Environmental influence on seminal traits in Holstein Friesian and Brown Swiss bulls born at tropical region. Rev. Fac. Agron. [online]. 2005, vol.22, n.1, pp.54-64. ISSN 0378-7818.

Two groups of five pure breed Holstein Friesian and Brown Swiss bulls were used to study their seminal traits in two season (dry and wet) at the Institute of Animal Industry Research Experimental Station, located on Maracay (Venezuela). At the same time, the environmental temperature, solar radiation, rectal temperature and respiratory rate on the seminal traits were studied. The 240 data, adjusted for de bull age, were analyzed for variance, regression, single and multiple correlation. The season showed high significance between all the spermatic characteristics, and the simple correlation indicated many influence in motility because of the increase the respiratory rate. The multiple correlation showed that the environmental effects on the seminal characteristics can be expressed by prediction equations to indicate the environmental effects on the physiological measure and their interrelation on the spermatic traits. All bulls showed abnormal values in seminal characteristic in the dry season.

Palavras-chave : Bull; Sperm; Tropic; Environmental; Adaptation; Bioclimatology.