On-line version ISSN 1678-4596
PEIXOTO, Luiz Antero de Oliveira et al. Protein metabolic profile and conception rate of beef cows kept on nature pasture or supplemented with wheat meal, with or without urea. Cienc. Rural [online]. 2006, vol.36, n.6, pp.1873-1877. ISSN 1678-4596. http://dx.doi.org/10.1590/S0103-84782006000600032.
This study evaluated the protein metabolic profile of beef cows supplemented or not, from calving to weaning; comparing urea nitrogen values, from milk and blood serum, with conception rate. 115 beef cows from Charolais, Nellore and its crosses were used. Cow's age ranged between 3 and 13 years old, and separate into three age classes: young, adult and old, being evaluate since calving until weaning, at day 63 postpartum. There was an interaction (P<0.05) between treatment and genetic group for serum urea nitrogen (SUN) level, being supplemented cows with urea at wheat meal presented SUN level higher than cows not supplemented and supplemented only with wheat meal (18.19 vs 14.54 e 12.48mg.dL-1, respectively). Serum albumin and milk urea nitrogen (MUN) levels didn't differ (P>0.05) between treatment and period. SUN and MUN levels and supplementation didn't influence conception rate.
Keywords : serum albumin; Charolais; Nellore; serum urea nitrogen; milk urea nitrogen; metabolic profile.