Mastitis diagnostic tests to estimate mammary gland epithelial cell damage.

Quarter fore-milk samples, blood serum, and mammary gland tissue extracts were tested for N-acetyl-B-D-glucosaminidae, lactate dehydrogenase, glutamate--oxaloacetate transmaninase, arylesterase, bovine serum albumin, sodium, conductivity, and somatic cell count. Bovine serum albumin, arylesterase, and sodium were high in blood serum while the first three listed were high in mammary gland tissue. All of these components in milk increased as somatic cell count increased. Correlation coefficients between somatic cell count and each component in order were .84, .53, .55, .81, .74, and .75. Some of these procedures (e.g., serum albumin, dehydrogenase, and transaminae) for estimating the extent of udder epithelial cell damage were less valuable because of lengthy assay times, tedious sample preparation, and unsatisfactory assay procedures. The most suitable approach for measuring udder tissue epithelial damage was the glucosaminidase test which was simple and rapid with high sample throughput. It should be a useful diagnostic aid in mastitis monitoring programs.