The effect of the concentration of β-hydroxybutyrate and glucose in the blood on the reproductive function and milk productivity of cows

The  intensity  of  metabolic  processes  in highly  productive  cows  is  associated  with metabolic disorders and the development of dystrophic  changes  in  the body.  The  paper evaluates the effect of the concentration of β-hydroxybutyrate and glucose in the blood of new-bodied cows on the indicators of reproductive ability and milk productivity. To do this, venous blood was obtained from cows of different ages after childbirth, where the concentration  of  glucose  and  β-hydroxybutyrate was determined. Depending on  the  level of glucose  and  ketone  bodies, animals  were  retrospectively  differentiated into groups and the severity of economically useful  signs  was  determined.  It  was  found that  cows  with  a  glucose  level  above  3.3 mmol/l  required  0.6  more  inseminations (P≤0.01), compared  with  animals  whose indicators  were  in  the  range  of  2.2...3.3 mmol/l. At the same time, the greatest difference in the multiplicity of insemination was present in animals 3...7 lactation (1.2 inseminations per fertilization; P≤0.001). The period from calving to fertilization in cows with a high glucose content was longer by 39.4 days (P < 0.05), while the maximum deviation was found among animals older than the 2nd  lactation  (by  43.4%;  P<  0.05).  An  increase in the level of β-hydroxybutyrate over 0.7 mmol/l was also accompanied by a deterioration in reproductive function. Thus, the lengthening  of  the  infertility  period  for  all lactation was 21.2 days (P≤0.05). The most pronounced negative effect on reproductive function in ketonemia was observed in first-heifers and cows of the second lactation. So, after  the  first  birth,  the  lengthening  of  the period from calving to fertilization was 42.0 days (P < 0.05), and after the second lactation - 29.2 days (P < 0.05). Thus, an increase in  the  level  of  glucose  and  β-hydroxybutyrate in the blood negatively affects, first of all, the reproductive function of cows, and to a lesser extent, the indicators of milk productivity.