Study of association between the electrical conductivity of milk and subclinical mastitis in dairy cows

Abstract

Mastitis has been a major problem facing the dairy industry from the very outset of farming, both in terms of an economic view point and the welfare of the cows. The stress that a mastitis infection can have on farmers cannot be neglected either. Farmers, veterinarians and industry experts have been working tirelessly to make the detection of mastitis more efficient. Numerous methods of detection are available to the dairy industry, visual inspection of the milk together with cow side tests such as the California Mastitis Test and handheld SCC detectors whilst samples can be sent to labs for bacterial culture. The aim of detecting mastitis at an early stage therefore enables the implementation of an early treatment program before any major economic impact can occur. In recent years the development of using electrical conductivity as a mastitis detection method has proved to be useful in terms of detecting clinical mastitis. With a higher degree of infection, the physical changes associated with CM are detected more reliably. Our aim was to prove if EC could be used as a valid detection method for sub-clinical mastitis. We examined results taken from a large-scale dairy farm who has automatic detection and recording facilities within the milking parlour. We examined three variable factors for each sample the milk yield, EC and milk flow. We were able to examine these factors when observed at different SCC thresholds.