Effect of indoor silage feeding on pasture time in a batch-milked automatic milking rotary system

摘要

The effect of indoor silage feeding on pasture time was studied in an automatic milking rotary system with batch milking two times daily. The objective was to study how pasture time is influenced by offering only pasture (PP) or both grass silage and pasture (SP) in the barn during grazing hours, in a night-time grazing system, where cows could move freely between barn and pasture during pasturing hours. From 9 June until 18 August, treatments SP and PP were repeated three and two times, respectively intwo-week periods using the second week for measurements. During each measurement week, ten animals were fitted with HOBO* loggers that estimated grazing time from head position. Results were analysed in a mixed repeated measurement model using only cows(83) present during all periods. Results showed that animals on treatment PP spent approximately 8.5 hours on pasture with no difference between primi- and multiparous cows. In contrast, cows on treatment SP spent less time on pasture (/)<0.00l) and furthermore, time on pasture differed significantly between ages (7)<0.001) in this group, with 4.7 h and 5.9 h for primiparous and multiparous cows, respectively. Analysis of data on the grazing hours, obtained from the HOBO loggers, showed a significant (P<0.001) difference between treatments with 3.8 and 2.2 hours of grazing on treatment PP and SP, respectively.