Investigations on automatically measured feed intake amount in dairy cows during the oestrus period

The aim of this study was to determine whether feed intake amount and feed intake behaviour could be related to oestrus in dairy cows. Furthermore, we investigated whether oestrus had an effect on daily milk yield. A total of 138 oestrus cycles, leading to conception of 100 cows, were analysed. The parameters "daily fresh matter intake amount (kg)", "daily number of visits to the feeding trough" and "time spent feeding per day (min)" were electronically measured and recorded. For a sub-quantity of all animals, daily milk yield (kg) was recorded continuously and stored in the herd management software. Special attention was given to the day of oestrus, which was defined as the day of successful insemination. All remaining days of the oestrus cycle were considered as the reference period. Among all animals and cycles, fresh matter intake amount per day, number of visits per day, and time spent feeding per day were reduced by 10.3, 9.1 and 20.8 %, respectively, on the day of oestrus. Fresh matter intake was significantly lower in primiparous cows than in multiparous cows. However, number of visits to the trough and time spent feeding per day were significantly higher in primiparous cows compared to multiparous cows. Day of oestrus did not have a significant effect on daily milk yield, as this parameter was characterized by high variation among all days of the oestrus cycle. In conclusion, if an RIC system is used, monitoring of feeding behaviour appears to be a potential auxiliary aid in oestrus detection