Effects of milkers' attitudes and behavior on cows' avoidance distance and impacts on udder health in Swiss dairy herds

Summary

In a cross-sectional study we investigated effects of milkers' attitudes and behavior on cows' behavior as well as their impacts on udder health while also considering herd management factors. All 46 investigated Swiss dairy herds were kept in loose housing systems. All farms participated in an extension program for preventive mastitis control. Milkers' attitudes were assessed by a questionnaire. Milkers' acoustic and tactile behavior as well as cow behavior were observed during milking. The cows' avoidance distances in the barn towards an unknown person were recorded. Furthermore, herd management factors were assessed by questionnaire guided interviews and observations, respectively. Udder health was evaluated using the indicators prevalence of quarters with elevated somatic cell counts (>100,000 cells/ml) and prevalence of mastitis quarters (>100,000 cells/ml and culturally positive) calculated from quarter-milk-samples of all lactating cows at the time of assessment. After univariable pre­selection of associated factors, multivariable linear regression models with stepwise backwards elimination of factors with P20.05 were calculated on herd Ievel. Lower cows' avoidance distances were associated with (1) positive milkers' attitude concerning importance of contact with their animals, (2) all milkers knowing all cows individually, (3) breeding selection on manageability, (4) generous dimensions of cows' lying places and (5) Ionger contact of the stockpersans with the animals during routine work. Predictors for higher prevalences of quarters with elevated somatic cell count were a lower percentage of positive interactions of milkers out of all interactions with the cows during milking (P=0.030) and a higher amount of fearful cows in the herd (with an avoidance distance above 1m; P=0.014). Higher prevalences of mastitis quarters were associated with (1) again a lower percentage of positive interactions of milkers during milking (P=0.033), (2) breed, especially Holstein in comparison to Swiss Fleckvieh (P<0.001), (3) higher Iactation number (P=0.020) and (4) generaus dimensions of lying places (P<0.001). In conclusion, human-animal-relationship was found to be relevant for udder health and should get more attention as one possible action point in extension programs for preventive mastitis control.