The influence of metritis and mastitis on dairy herd fertility: some case examples

UK Vet Vol 15 No 6 October 2010 38 INTRODUCTION The decline in dairy herd reproductive performance over the last 20-25 years or so has seen a fall in heat detection rates accompanied by a fall in conception rates (Lucy, 2001; Royal et al., 2000). This has led to the development of a variety of systems of heat detection, aimed at increasing the number of cows detected in heat thus increasing submission rates, in the simple belief that, providing egg and sperm are brought together in the right place at the right time, conception success is assured. However, if heat detection were the sole problem relating to the decline in performance then surely conception rates would have remained static? The question then arises that if the methods of heat detection that have been employed over the last 20-25 years are accurate, and the quality of purchased semen has been maintained, there must be other factors on the female side which have contributed to the decline.