The relationship between udder skin surface temperature and milk production and composition in dairy cattle (Bos taurus Linnaeus, 1758)

The aim of the present study was to determine correlations between udder skin surface temperatures and milk yield and estimated composition in dairy cows. The thermographic images of 34 Polish Holstein-Friesian black-and-white cows were taken in a milking parlor before and after milking. Partial correlation coefficients were calculated between the surface temperatures of the udder hind quarters and milk production traits controlling for age, parity, year, and milking time. Daily milk yield was weakly and nonsignificantly correlated with surface temperatures (r(p) ranging from -0.19 to 0.21), except for the mean and maximum temperatures of the left hind quarter after milking (r(p) = 0.40 and r(p) = 0.38, respectively). There were significant correlations of skin surface temperature with estimated fat content (r(p) = -0.55 to 0.48), protein content (r(p) = -0.39 to 0.42), fat yield (r(p) = -0.42 to 0.54), and protein yield (r(p) = 0.37 to 0.54). The estimated somatic cell count was significantly correlated with the minimum temperature (r(p) = -0.54 to -0.36). The estimated urea content was significantly correlated with the minimum temperature (r(p) = 0.52). A larger sample size is required in future research to confirm these preliminary results.