'Universidade de Sao Paulo, Agencia USP de Gestao da Informacao Academica (AGUIA)'
Doi
Abstract
Thirty Brangus bulls were used in a 90-d study to assess the effect of artificial shading on the performance and
reproductive characteristics of semi-confined cattle. Animals were kept in four one-ha paddocks in two groups of
eight for shade treatment (5 m²/animal of 80% solar block shade cloth) and two groups of seven animals in no-shade
treatment. Each treatment had two homogeneous groups, each divided into heavy-bulls (351-450 kg) and light-bulls
(300-350 kg). Time spent under shade, time standing, average daily gain, testicular development and sperm quality
were investigated. Animals spent 24% of the daylight under the shade and no-shaded bulls spent more time standing
(P 0.05) and testicular development between shaded and
no-shaded animals. However, scrotal perimeter was higher for shaded light animals compared to no-shaded light
bulls (P < 0.10). Sperm motility increase during the experimental period for shaded animals (P < 0.05) and sperm
abnormalities were higher for the shaded ones (P < 0.05). Although the results did not indicate pronounced benefits on
cattle performance, this resource was an important alternative because it appears to provide an improvement in some
reproductive parameters and ensure a better thermal comfort to the animals
