C.W. Arave

Relationship of Three Measures of Behavior to Milk Production

Abstract Nine commerical herds were observed on three separate occasion for flight distance, i.e., how close a human can come before a stationary cow moves away, and approach distance, i.e., how close a cow will come to a stationary human. Herdsmen from each herd scored their cows on parlor behavior using a scoring system that ranged from 1 (the most docile) to 5 (the most aggressive). These three behavior factors were compared with milk production. Both mean flight distance and mean approach distance were 1.6 m. Mean parlor score was 2.2 and mean production was 9153 kg. These were significant inter-herd correlations between flight distance and approach distance (r=0.30), flight distance and parlor score (r=0.20), and parlor score and milk production (r=0.08); however, only flight distance and approach distance (r=0.18), and flight distance and parlor score (r=0.12) were significantly correlated within herds. There was no significant intraherd correlation between milk production and any of the behavioral factors considered. These findings indicate that while parlor score is associated with milk production across herds, flight distance and approach distance are not useful indicators of milk production.

Behavior and maze learning ability of dairy calves as influenced by housing, sex and sire

Abstract Two-hundred-and-seventy-five calves were allowed to enter a maze to determine how genetic and environmental effects influenced their time, direction first turned upon entry (laterality), and activity in a maze. Calves were put into the maze five times on Days 1, 2 and 3 post-weaning. Diet did not affect time, distance traveled, or activity score in the maze of 53 calves. On Day 2, males were slower to find the food source than females. On Day 3, calves reared in polyvinyl domes initially turned right more often than explained by chance. Activity differed between calves from different sires, sexes, during certain trials, and when the location of the food source was changed. There was nearly a threefold difference between sire groups in time required to pass through the maze. Maze time was slowest on Day 1, fastest on Day 2, and intermediate on Day 3 (when the location of the food source was changed). Sire groups differed in activity scores on all 3 days. There were significant correlations between maze time and activity scores, between activity score and laterality and between time and laterality on some days.

Isolation vs. group rearing in monozygous twin heifer calves

Abstract Seven pairs of monozygous (MZ) twin heifer calves were assigned at birth to either isolation or group rearing. The isolation effects on feed intake, social development, survival activity, and learning ability were studied. There were no differences found in the average daily gain between the isolates and the group reared calves. Large variations in feed intake were randomly distributed across the treatments. There were no correlations between dominance rank at 15–17 months of age and body weight or age. An intraclass correlation of 0.93 between twin pairs indicated a strong genetic base for dominance. The group calves spent significantly longer eating than isolates. It was found that time recumbent did not differ, nor did laterality, between rearing regimes. The isolates achieved their goal in T-maze tests in significantly less time than group calves in the first 2 days of a 3-day trial. In comparing isolation rearing with weaning, there appeared to be no measurable detrimental effect on the calves and it may have enhanced their human-animal bond.

Discriminability and preference among milking machine functions by dairy cows

Abstract An attempt was made to assess discomfort to the cow associated with milking machine function. Seven cows were presented with conditional discrimination tasks between alternative stimuli, using operant conditioning procedures. No discrimination between stimuli was evident. When allowed to choose between wide and narrow pulsation ratios, the 7 cows failed to do more than respond randomly. Four of the cows who were given a choice between potentially more or less aversive stimuli, pulsation vs. zero pulsation, showed no clear preference. The data suggest either that cows cannot discriminate within the experimental range of machine functions, i.e. that no measurable preference existed, or, under the experimental methods used, that cows could not learn the conditional discrimination required.