Ghrelin and orotic acid increased in subclinical mastitis.

Hormone ghrelin and orotic acid accelerate wound healing as well as controlling inflammation and immunity. We have, therefore, investigated the serum and milk levels of ghrelin and orotic acid in dairy cows with (n = 21) or without (n = 21) subclinical mastitis. Acylated and des-acylated ghrelin as well as orotic acid concentration were detected by using high performance liquid chromatography (HPLC). The results revealed that ghrelin level in milk and serum was significantly higher in dairy cows with subclinical mastitis than that of dairy cows without subclinical mastitis. This was also the case when the orotic acid concentrations in dairy cows with subclinical mastitis were compared with those dairy cows without subclinical mastitis. In conclusion, ghrelin and orotic acid occur in particularly high concentrations in subclinical mastitis, and might, therefore, be required in greater amounts for tissue repair and may be also used as a indicator for subclinical mastitis.

Lack of correlation between the electrical conductivity of milk and the blood progesterone levels in cows.

A study was conducted to investigate the possibility of measuring the electrical conductivity (EC) of cow's milk as a practical and cost-effective means of determining oestrus in cows. Prostaglandin injections were used to synchronise the oestrous cycle of 15 cows. From the onset of oestrus, milk and blood samples were collected from each cow every 2nd day over a period of 22 days. A portable, commercially available instrument was used to measure the EC of the milk. The blood progesterone levels were determined by means of an enzyme immuno-assay method. No correlation was found between the EC of milk and the blood progesterone levels of the cows tested. Electrical conductivity measurements of milk are of no value in determining the onset of oestrus in cows.

An investigation on plasma progesterone levels during pregnancy and at parturition in the Ivesi sheep.

In this study, plasma progesterone concentrations in a total of 45 Ivesi sheep were investigated during pregnancy and at parturition. Blood samples were collected from all the sheep studied every 20 days commencing on the 30th day of pregnancy. Plasma progesterone levels were determined by radioimmunoassay. During the second half of the pregnancy, progesterone concentrations in the sheep giving birth to one, two and three lambs were 2.02 +/- 0.08 ng/ml, 3.24 +/- 1.18 ng/ml and 4.90 +/- 0.85 ng/ml, respectively. There was no significant variation in progesterone levels between sheep with male and female offspring. At parturition, plasma progesterone concentrations did not differ significantly between the animals. The present results indicate that plasma progesterone levels could be used not only to determine the pregnancy status of the animal but also to predict the number of fetuses after the second half of the pregnancy.