Relationships between human-animal interactions and productivity of commercial dairy cows.

This study examined the relationships between a number of stockperson and cow variables at 66 commercial dairy farms. Variables such as the attitudes and behavior of stockpeople toward their cows and the behavioral response to humans and productivity of cows were studied over one lactation. There were consistent and significant correlations between some of these stockperson and cow variables. For example, a positive attitude by stockpeople toward the behavior of dairy cows was negatively correlated with the number of forceful, negative, tactile interactions used by stockpeople in handling cows (r = -0.27, df = 127, P < 0.01). Furthermore, based on farm averages, the number of forceful, negative, tactile interactions used by stockpeople was negatively correlated with the percentage of cows approaching within 1 m of an experimenter in a standard test (r = -0.27, df= 64, P< 0.05). Although not confirming a fear-productivity relationship, a moderate but nonsignificant correlation was found between flight distance of cows to an experimenter in a standard test and milk yield (r = -0.27, df = 33, P > 0.05). Support for the existence of a negative fear-productivity relationship was the finding that the use of negative interactions by stockpeople was significantly and negatively correlated with milk yield, protein, and fat at the farm (r = -0.36, -0.35 and -0.33, respectively, df = 64, P < 0.01) and was significantly and positively correlated with milk cortisol concentrations at the farm (r = 0.34, df= 64, P < 0.01). Furthermore, the percentage of cows approaching within 3 m of an experimenter in a standard test was positively correlated with conception rate to the first insemination (r = 0.38, df = 46, P < 0.01). The significant correlations found in the present study between stockperson attitudes and behavior and cow behavior and productivity, although not evidence of causal relationships, indicate the possibility of targeting these human characteristics to reduce fear responses of dairy cows to humans and improve the cows' productivity.