| dc.description.abstract | In conclusion, there is a lower reproductive efficiency in the tethered herds, with higher calving interval, CFI, CLI, number of AI and non return rates, compared to the free kept herds in the given areas of Norway. The effects of herd size to the reproductive efficiency are not conclusive, and there is need of larger analytic material and better analytical method to give a clear evaluation of how the size effects the reproduction in Norway. There is a higher treatment rate of ketosis in tethered herds than in free keeping herds, but the other postpartum diseases show no difference between size of the group and keeping method. The treatments to the reproductive tract from 2005 show higher treatment rates in tied herds with the exception of metritis. The milk production a year cow has increased steadily the last decade and it does not seams to yet have had any great influence on the reproductive efficiency of the NRF, which still have good fertility parameters with a slight decline in calving interval from 2005, but the postpartum disease showed better or similar tendencies. | en |
