Proteic supplements with and without sulfur sources on intake behavior of steers fed with low quality hay

Abstract

This experiment was conduct to study the effects of proteic supplementation and different sulfur sources added to supplements on the intake behavior, for cattle. Seven Holstein steers, weighing 442 kg ± 59 kg of live weight. The statistical design was a Latin square 7 x 7, and treatments consisted of the supplements use or no with addition or no of different sulfur sources: hay + supplement without sulfur (SWS), hay + sulfur 70S (S70), hay + sulfur 98S (S98), hay + calcium sulfate hemi-hydrated (CSH), hay + calcium sulfate di-hydrated (CSD), hay + ammonium sulfate (SFA) and hay without supplement (FSS). The Supplements affected in a positive way the feeding, chewing and resting activities. Steers without supplement (HWS) showed shorter total time of feeding, lower total time of chewing, and resting than steers with supplements. They had shorter meals and spent more time for rumination chewing per ruminal bolus, had lower efficiency of feeding (g DM/hour) and lower rumination efficiency (g of DM/hour and g of NDF/hour) as well as of the lower intake. SWS showed higher total time of rumination then supplements with different sulfur sources. The animals that had consumed supplements with sulfur, had presented lower number of rumination chews per day and per bolus, but they had not different to feeding efficiency and rumination.