Biomarkers from automatic milking system for cows reproduction success

Abstract

This Research Communication addresses the hypothesis that some biomarkers from automatic milking system can be indicators of cows reproduction success. The pregnancies were tested with ultrasound after 30–35 d post-insemination. Those cows which were pregnant were assigned to the PG+ group (n = 36) and those which were not pregnant, were assigned to the PG- group (n = 32). On oestrus day the pH, temperature of the contents of cow reticulorumens and cow activity were measured using specific smaX-tec boluses manufactured for animal care. Rumination time, body weight, milk yield, milk fat – protein ratio, milk lactose, milk somatic cell count, milk electric conductivity of all quarters of udder (front right, front left, rear left, rear right), and consumption of concentrates were registered with the help of Lely Astronaut® A3 milking robots.We estimated that the reticulorumen pH (P < 0.001) and reticulorumen temperature (P < 0.01) were higher in PG+ cows compared to PG− cows, which were found to have higher (P < 0.001) productivity (MY). Between the reticulorumen pH and the MY in PG− cows a positive relationship was calculated (P<0.001). In PG+ group was estimated a higher milk fat ant protein ratio (F/P = 1.19 ± 0.013) compared to PG− group (P < 0.001) and a higher content of milk lactose (4.59 ± 0.003%; P < 0.001). Cows of PG + group were more active compared to the PG− group (1.94%; P < 0.001) and consumed less concentrates (17.50%, P < 0.001). We can conclude that higher reticulorumen pH and temperature, milk lactose and lower consumption of concentrates and higher activity of cows were associated with the reproduction success. Correlation coefficients between values of automatic measurements of reticulorumen pH and temperature in PG+ and PG− cows were fluctuating and differed at different times of day. Analysis multivariable logistic regression have shown that the key reliable indicators of cow reproduction success are changes in productivity and activity.