Against the background of decreasing reproduction efficiency, estrus detection is gaining increased importance. The objective of this study was to evaluate changes of feeding characteristics and rumination time in dairy cows in the days around estrus. Feeding characteristics were recorded by weighing troughs, and rumination time by acoustic sensors. Analysis included data from 25 primiparous and 37 multiparous cows, which were successfully inseminated (day of insemination=d 0). Feeding time and rumination time were decreased on d -1 and 0, feed intake, and feeding rate on d 0. Primiparous and multiparous cows differed in their reference values, but their feeding and rumination times on the day of insemination were reduced to similar extents. Rumination time was reduced in a time frame of 30 h around estrus whereby the main drop was found during the time period between 0600 h on d -1 and 1200 h on d 0. The change of almost all evaluated feeding characteristics and rumination time around estrus indicated their potential for useful addition in early detection of estrus.

Monitoring rumination behavior serves multiple purposes in feeding and herd management of dairy cows. The process of calving is a major event for cows, and a detailed understanding of alterations in behavioral patterns of animals in the time around calving is important in calving detection. The objective of this study was to describe the short-term changes in rumination patterns in dairy cows immediately before and after parturition. In total, 17 cows were fitted with rumination sensors that were able to monitor rumination time, number of rumination boli, and number of rumination jaw movements. Rumination time was decreased in the last 4h antepartum and in the first 8h postpartum. Cows stopped ruminating 123 ± 58 min (mean ± standard deviation) before calving and resumed ruminating 355 ± 194 min after calving. The number of rumination jaw movements and boli per day were decreased in the 24-h period postpartum. Rumination rate, the number of rumination jaw movements per rumination minute, and the number of boli per rumination minute changed little around calving. The calving event primarily influenced the duration and frequency of various rumination characteristics but not rumination intensity. Among detected characteristics, rumination time showed the greatest potential for monitoring of calving events.

Results of recent in vitro experiments suggest that essential oils (EO) may not only influence ruminal fermentation but also modulate the absorption of cations like Na+, Ca2+ and NH4 + across ruminal epithelia of cattle and sheep through direct interaction with epithelial transport proteins, such as those of the transient receptor potential family. The aim of the current study was to examine this hypothesis by testing the effect of a blend of essential oils (BEO) on cation status and feed efficiency in lactating dairy cows. In the experiment, 72 dairy cows in mid-to-end lactation were divided into two groups of 36 animals each and fed the same mixed ration with or without addition of BEO in a 2×2 cross-over design. Feed intake, milk yield and composition, plasma and urine samples were monitored. Feeding BEO elevated milk yield, milk fat and protein yield as well as feed efficiency, whereas urea levels in plasma and milk decreased. In addition, plasma calcium levels increased significantly upon BEO supplementation, supporting the hypothesis that enhanced cation absorption might contribute to the beneficial effects of these EO.

Monitoring of feeding and rumination behaviour can provide useful information for dairy herd management. The feeding behaviour of dairy cows can be recorded by different techniques, such as video cameras, weighing troughs or chewing sensors. Among feeding characteristics, individual feed intake of cows is of utmost interest, but as weighing troughs have high space and cost requirements they are used primarily in research studies. The objective of the present study was to evaluate whether records on feeding time or chewing activity or a combination of both contain enough information to estimate feed intake with sufficient accuracy. Feed intake and feeding time per cow were recorded by means of weighing troughs. Concurrently, chewing activity of seven cows was recorded by MSR-ART pressure sensors during five to eight measuring days per cow. Feeding and chewing behaviour were evaluated in time slots (1 min) and additionally assigned to feeding bouts for further analysis. The 1 min time slots were classified into feeding/no feeding or chewing/no chewing by the two systems, and agreement was found in 92.2% of the records. On average, cows spent 270 ± 39 min/day at the feeding troughs and chewed 262 ± 48 min/day. The average fresh matter intake (FMI) was 49.6 ± 5.1 kg/day. Feed intake was divided into 9.7 bouts/day during which cows fed in average 27.8 ± 21.7 min/ bout and chewed 27.0 ± 23.1 min/bout. The correlation between FMI and feeding time was r = 0.891 and between FMI and chewing time r = 0.780 overall cows. Hence, both systems delivered suitable information for estimating feed intake.