Behavioral and physiological responses of crossbred Holstein-Zebu cows and their interaction with the milker in two milking systems

Abstract

The aim of this study was to evaluate the behavioral and physiological responses of dairy cows and their interaction with the milker in two types of milking systems. The experiment was conducted in two farms, in the Coração de Jesus city, Brazil, where the surface temperature (TS, °C), rectal temperature (TR, °C), respiratory rate (RR, breaths.min -1 ) and heart rate (HR, beats.min -1 ) of 44 crossbred cows during the morning shift on twelve days of data collection at each farm. It was monitored the meteorological variables: the black globe temperature (TGN, °C), air temperature (TAR, °C), relative humidity (RH, %) and wind speed (V, m.s -1 ). Observations about human behavior, negative patterns (tapping, yelling, and pushing) and positive patterns (talking, groping, and naming) were made without people being aware of their nature. The behavioral data observed in the animals were: vocalization (VOC), defecation (DEF), micturition (MIC) and movement (MOV) and milking time (TOR) was also recorded. The physiological variables were significant among farms, except heart rate. The talking, naming, pushing and shouting actions were not significant, only groping and hitting. The behavior occurrences VOC, MIC, and MOV of cows were low. The TO presented a positive correlation (P <0.01) with TS, TR, and HR and negative correlation (P <0.01) with RR. Under the conditions of this experiment, the type of milking system influenced the physiological responses. The milking system of type "bucket at the bottom" provided greater contact between the milker and the cow, leading to a greater negative interaction reflected by the defecation behavior.