Effect of propylene glycol in the diet of close up cow on subclinical ketosis

الملخص EN

The objective of this study was to determine if use of propylene glycol in high producing dairy cows diet during the transition period, consisting of the 3 wk before and 3 wake after calving, and continued for 6 to 8 weeks post partum,could reduce the risk of SCK after calving, and to investigate the difference form use of propylene glycol on the concentrations of the different metabolities in milk and blood and to evaluate the effect of metabolities concentrations in the detection of subclinical ketosis in two groups of Holstien cows.

First group have propylene glycole as feed additives in its diet second group have no feed additives in its diet.Cows were defined subclinically ketotic when their concentration of blood β- hydroxybutyrate was over 1200μmol/L.

Determination ofβ- hydroxybutyrate in the milk via an enzymatic analysis or via the Ketolac strip test provided valuable results, with threshold concentrations of 70 and 100μmol/L, respectively.

The simplicity of use of the Ketolac strip test makes it a valuable way to investigate subclinical ketosis