Maternal behavior before and after parturition of red Angus beef cows and the investigation of wolf predation on livestock populations in the Northern Rocky Mountains.

摘要

The objective of this dissertation was twofold: 1) define maternal behaviors such as protectiveness and defense towards the offspring after parturition, and 2) examine depredation losses in cattle in areas with high predation pressure. All experiments incorporated the temperament of the animal, measured by the facial hair whorl pattern (HW) on the forehead of the animal.;To define maternal behaviors, we conducted three experiments. In experiment one, each cow-calf pair was approached with an unfamiliar utility vehicle that circled the pair and gradually decreased the distance to cow and calf (N = 341). Four distance measurements were taken with a digital range finder to evaluate maternal protectiveness. Calf defense behavior patterns were recorded as yes/no-classifications and were: protection: the cow positioned herself between the vehicle and her calf; aggression: the cow lowered her head; and vocalization. This study showed that 99% of the cows moved between the vehicle and their calf to protect it, 13.2% lowered their heads as a sign of aggression and 78% vocalized.;Experiment two investigated the separation distance from the herd for parturition and the relationship between age and temperament on the separation. By measuring the distance (m) between the birth place of each individual cow and the main herd with a GPS device we could determine the separation distance at parturition (N = 333). Our study shows that more dominant and older cows calve closer to the herd and younger, more inexperienced cows calve further away at random places.;Experiment three analyzed a possible connection between the temperament, measured by the facial HW, age and body conditions of the cow on physiological traits of the calf. Physiological measurements of the calf were: calf birth weight, gender, ADG, weaning weight and days until weaning. Complete records of 507 cows and calves were analyzed. Calf birth weight and weaning weight were influenced by the gender of the calf (P < 0.001; steers were heavier than heifers) and by the cow weight (P < 0.001; heavier cows give birth to and wean heavier calves). There was a tendency of HW to affect the birth weight (P = 0.093; cows with middle HW gave birth to the heaviest calves) and an effect on weaning weight (P = 0.043, cows with abnormal non-spiral HW weaned heavier calves compared with normal round spiral HWs). The age of cows had no effect on calf birth weight (P = 0.593) but affected the weaning weight (P < 0.001). Older cows wean heavier calves. Further, the body conditions of calves depend on the physiological constitution of the cow. Selection towards cows with abnormal HW should however be prevented because earlier findings reported sperm abnormalities in bulls with abnormal HW.;The second emphasis of this dissertation was to examine depredation losses of cattle in areas with high predation pressure. A herd of 588 Black Angus x Charolais crossbreds (age range: 5-17 years old) was used for observations. We identified a connection between the HW, the age of a cow and the depredation loss (P < 0.001). The HW of a cow significantly influenced the probability of losing the calf to predation (P < 0.001). Cows without the facial HW faced the highest number of losses (probability of 19.6% of losing the calf) compared to other HWs (probability between 0 - 6.1%). We also found an age effect on the probability of losing the calf (P = 0.023). Cows over the age of 10 years have an increased probability of losing their calf to predation. Our findings suggest that behavioral differences between cows with different HWs exist. Differences in protectiveness or vigilance towards the surroundings in cows without a facial HW may lead to an increased probability of losing the calf to predation. (Abstract shortened by UMI.).