Variability of laboratory parameters of the metabolic profile in ketosis in cows: Is only comparison with reference values sufficient

Abstract

Ketosis is a significant metabolic disorder in cows that occurs as a result of a negative energy balance, when the concentration of ketone bodies in the blood, milk and urine increases. Cow ketosis is a metabolic disease characterized by a disturbance in carbohydrate and fat metabolism with increased production of ketone bodies in the body. Basic metabolic adaptations in cows in ketosis are: increased concentration of BHB, increased concentration of NEFA, lower concentration of glucose, increased value of liver enzymes and bilirubin, disorder of macro and micro elements, increased values of inflammatory markers, oxidative stress, insulin resistance, and are accompanied by various associated diseases and behavioral disorders. Given that ketosis often occurs in different forms, and that the obtained values of the metabolic profile for most parameters remain within the reference values, it is necessary to examine the variability of blood parameters in order to recommend a new way of interpreting the metabolic profile in the assessment of ketosis in cows. We expect to determine which parameters show the greatest degree of variability, which will allow us to make a practical contribution to the diagnosis of ketosis, because we will determine the parameters that are most sensitive to ketosis, and whose variability in combination with specific changes in the BHB value allow not only the diagnosis of ketosis, but also the graduation its weight in each cow separately. The everyday practical way of assessing the health of animals is reflected in the comparison of the obtained values with the reference values, therefore it was necessary to determine in what percentage there is a large deviation of the parameter values (Z score above or below 2), which in a practical sense means that there has been a change obtained values outside the reference ones. When BHB is excluded, whose high deviation is the basis of the definition of ketosis, and the values of other metabolic parameters are observed, we conclude that in 360 measurements there are 105 deviations from the reference values, which is 29.17%, while in 70.83% of the measurements, the values of metabolic parameters are were within the reference values. The above results indicate that in practice a new way of reading and interpreting the results must be approached, which must take into account the position of the metabolic parameter value within the reference value, and not just the fact whether the metabolic parameter is outside the reference values.