Determination of the relationship between milk urea nitrogen (MUN) and nutritional levels in dai̇ry cows

Urea consists of carbon, nitrogen, oxygen and hydrogen and is a small organic molecule found in blood and body fluids. Urea is also a normal component of milk and the amount of urea in the milk is called milk urea nitrogen (MUN). In recent years, the term " milk urea nitrogen ", which is used as a biological indicator of the nutrition status of dairy cows, has started to attract attention. This study was carried out to determine the relationship between the amount of milk urea nitrogen and nutrition level in dairy cows. The research material is milk samples collected from 100 different dairy farm. Four milk samples were taken from each of the farm and a total of 400 milk samples were collected. Milk samples were placed in 50 ml sterile tubes and added protection tablet to each sample to prevent their deterioration. MUN, betahydroxybutyric acid (BHBA) and acetone levels were measured in all samples. According to the analyzes, those with MUN values between 12-16 mg / dl in milk samples were considered to be normal (group A), those below this value were low (group B) and those above were considered to be high (group C). In addition, acetone and BHBA moreover, total solid matter, fat, fat-free dry matter, crude protein, lactose, saturated fatty acids, total unsaturated fatty acids, PUFA, MUFA and aflatoksin M1 values measured in milk were compared with low, normal and high urea nitrogen values. Acetone and BHBA values are the most important predictors of early lactation dairy cows diseases such as ketosis and liver fatigue. Therefore, the presence of some nutritional diseases in these farms that cannot be diagnosed and diagnosed subclinically is evaluated by measuring these parameters. One-way analysis of variance (ANOVA) was used to compare the differences between the groups. Tukey-Kramer test was used as a post-hoc test in order to determine which group was the difference between the difference groups. The significance level was taken as P <0.05. In the study, the MUN values of the groups were 14.46, 10.05 and 20.15 mg / dl, respectively. At the end of the research, acetone values of the milk obtained from the groups were 0.282, 0.276 and 0.256 mmol / L, respectively. Although this result is statistically significant (P <0.05), the values of all three groups are among the normal acetone values determined for dairy cows. Similarly, there were differences in milk BHBA values (P <0.01). These values are 0.120, 0.086 and 0.080 mmol / L, respectively. As a result, detailed studies are needed to obtain a deeper understanding of MUN levels in milk cows between acetone and BHBA values and metabolic diseases.