Effect of Afterstimulation on Milk Yield and Fat Composition in Beef Cattle: A Form of Honest Begging?

Abstract

Nine suckling calves were allowed to afterstimulate their dams at three levels, ad libitum , for 3 min or none, at each suckling meal twice daily in a repeated 3 2 3 Latin square experimental design. Each experimental unit consisted of one cow-calf pair for 6 days. Milk yield was recorded and samples were taken at the morning meal on day 7 by hand-milking one quarter while the calf suckled the other three. Samples were analysed for fat content and 19 fatty acids (FA), summarized in five groups: locally synthesized FA, FA deriving mainly from blood serum (BSFA), saturated FA (SFA), unsaturated FA (USFA) and essential FA (ESFA). Variables were expressed as g g -1 fat, kJ g -1 fat, g kg -1 milk delivered at the recorded suckling meal and kJ kg -1 delivered milk. The only factors affected were milk yield, and BSFA, SFA, USFA and ESFA when related to the delivered milk. The relationship between levels of AS and milk yield was a second-degree polynomial.