Theme 22: Grazing Management
Description
The objective of this study was to evaluate the effects of grazing intensification on birth weight (BW), weaning weight (WW, standartized to 205 days), average daily gain from birth to weaning (ADG), and gestation length (GL) of calves, cow weight at calving (CWC) and at weaning (CWW), cow condition score at calving (CCC) and at weaning (CCW), and BW/CWC (BWR), WW/CWC (WWRC) and WW/CWW (WWRW) ratios. One hundred and sixty eight Nellore calves born in 1998 and 1999, out of dams maintained in two grazing management systems were evaluated: an extensive 1.0 animal unity (AU). ha-1 system on unfertilized Brachiaria decumbens pasture (SR); and an intensive rotational 5.0 AU. ha-1 system on fertilized Brachiaria brizantha cv. Marandu and cow-calf feed supplementation during dry season (SI). Analyses of variance showed a significant (P< .01) system effect on CWW and CCW, independently of year of birth of calf, a significant (P< .05 and P< .01) year of birth x system interaction effect on WW, ADG, BWR, WWRC and WWRW, and no effect at all on BW, CWC, CCC and GL. Results suggest that benefits of intensification were through improving production per hectare and not per animal.
Included in
Performance of Nellore Cattle under Two Grazing Management Systems
The objective of this study was to evaluate the effects of grazing intensification on birth weight (BW), weaning weight (WW, standartized to 205 days), average daily gain from birth to weaning (ADG), and gestation length (GL) of calves, cow weight at calving (CWC) and at weaning (CWW), cow condition score at calving (CCC) and at weaning (CCW), and BW/CWC (BWR), WW/CWC (WWRC) and WW/CWW (WWRW) ratios. One hundred and sixty eight Nellore calves born in 1998 and 1999, out of dams maintained in two grazing management systems were evaluated: an extensive 1.0 animal unity (AU). ha-1 system on unfertilized Brachiaria decumbens pasture (SR); and an intensive rotational 5.0 AU. ha-1 system on fertilized Brachiaria brizantha cv. Marandu and cow-calf feed supplementation during dry season (SI). Analyses of variance showed a significant (P< .01) system effect on CWW and CCW, independently of year of birth of calf, a significant (P< .05 and P< .01) year of birth x system interaction effect on WW, ADG, BWR, WWRC and WWRW, and no effect at all on BW, CWC, CCC and GL. Results suggest that benefits of intensification were through improving production per hectare and not per animal.
