Monitoring of physical activity for management of cow reproduction

The objective of this paper was to assess by means of pedometers the period of anoestrus in a herd where the calving interval was 400 days and to detect the influence of some factors (breed, year, season, parity) on the length of anoestrus and the intensity of increased physical activity during oestrus. It was also monitored whether the intensity of increased physical activity would influence the conception rate. The observations were performed in a herd of 243 cows, 80 of them Czech Pied cows (C) and 163 of themHolstein cows (H) during 4 years. The cows were housed together in a free cubicle housing system. The cows of H breed produced 3 790 kg and those of C breed 3 087 kg of milk on average during the first 100 days of lactation. The mean calving interval was 400 days, and the mean number of services per pregnancy was 2.1. The cows were fed a total mixed ration. This ration has a low energy content (NEL) and excessive content of crude protein according to the official evaluation used in theCzechRepublic. The intake of NEL ensured the production of 30.9 l of milk and the intake of crude protein in 45 l of milk in these cows. The cows of both breeds significantly differed in the length of postpartal anoestrus, which is probably related to the negative energetic balance of H cows. The effect of parity, year of calving, and season of calving on the length of postpartum anoestrus was not demonstrated as statistically significant. A comparison of the walking activity over the oestrus period in the individual breeds demonstrated that the cows of the Czech Pied breed exhibited significantly higher activity. The highest walking activity was observed in first-calvers of both breeds, and the lowest walking activity during oestrus was recorded in winter. The cows with higher walking activity had a higher conception rate than those with lower walking activity.