Applied Animal Ethology最新文献

Short-term increases in the milk yield of lactating dairy cows were found to be associated with increases in the occurrence of flinching, stepping and kicking which occurred curred during the milking process. Since the nature of the observed relationship between increased objectionable behaviours during milking and milk yield is unknown, culling dairy cows using behaviour during milking as the sole criterion may not be economically justifiable.

A technique is described for recording butting activity in individually penned sheep as an index of aggression. The method used wall-mounted reflective sprung panels which, when depressed in response to a butt, activated totalising electronic counters automatically printing-out every hour. Eight Dalesbred wethers were tested using this system over a 5-week period. During the first week, the animals received no treatment and the panels were used sporadically. However, during Weeks 2–5, sheep (N = 4) treated with testosterone propionate (20 mg/day) increased their butting activity, whereas those (N = 4) similarly treated with dihydrotestosterone propionate did not. The results suggest that non-aromatizable androgens may not support aggression in the ram.

Japanese quail (Coturnix coturnix japonica) exhibit cyclic baseline levels of dust-bathing when permitted ad libitum access to a particulate substrate; on a 10 h light:14 h dark photoperiod, the birds confine the bulk of their dust-bathing to 7 ± 2 h after light onset. This study tested the hypothesis that the cyclicity simply reflects stimulus (or response) satiation and recovery therefrom. Birds were induced to satiate to dust prior to the “normal” daily peak period, or were prevented from dust-bathing until near its end. Those that satiated prior to the normal period also exhibited amounts of dust-bathing later the same day comparable to normal baseline levels exhibited by control birds. Birds that were not permitted to dust-bathe until near the end of the normal period exhibited exceptionally high levels of dust-bathing when deprivation was terminated, so that their totals for the normal period were comparable to the totals of birds in the other groups. Thus, the effects of deprivation appear to be additive with respect to a normally cycling baseline level, which is not disturbed by manipulations of the expression of the behaviour.

The changes occurring in an experimental piggery during temproary power failure, which stopped controlled ventilation, were recorded in six experiments. The changes were influenced by: (1) the position of the emergency ventilation panel — whether it fell out or stayed in; (2) the activity of the pigs; (3) the temperature outside the building at the time of the power cut. The pigs were less disturbed by increases in temperature than by decreases. The temperature inside the building dropped when it was cold outside and when the ventilation panel fell out. Otherwise, the temperature and relative humidity increased during power failures. It is concluded that the effects of short-term power failure are more harmful in very hot or very cold weather than in moderate weather. The effects in cold conditions can be ameliorated by leaving the ventilation panel in, but this should be a short-term measure.

The literature on the feeding, eliminative and resting behaviour of horses has been reviewed to collate the information available on these subjects.

The grazing and eliminative behaviour patterns of domestic horses are unlike those of free-ranging Equidae. The reasons for this are not known, but it can cause wasted grazing of up to 90% of a field. Certain conditions, such as provision of supplementary hay and lack of available herbage, can cause these behaviour patterns to change, although it is not known how to manipulate the grazing behaviour of horses to prevent deterioration of the pasture.

Grazing behaviour is influenced by many variables and is more complex than the feeding behaviour of a stabled horse.

Horses sleep for approximately 12% of the day and show 4 different sleep/wakefulness states — alert wakefulness, drowsiness, slow-wave sleep and paradoxical sleep. Horses are able to maintain slow-wave sleep while standing, but they need to lie down for paradoxical sleep to occur, rarely spending more than 30 consecutive minutes in lateral recumbency.

Dalesbred, Jacob and Soay ewes were tested in a T maze to observe the behaviour of the ewes when given a choice between going near to their own lambs or to a group of ewes and lambs from the flock. The sheep were tested when the lambs were 2, 9, 21 and 42 days old. Most of the ewes ran to their lambs as a first choice. There was no breed difference in time to run or choice made with all the age groups, but the ewes moved away from the lambs more quickly as the lambs got older. The Dalesbred ewes stayed close to their lambs for longer than the other ewes when the lambs were 2 and 9 days old. The Soay ewes spent the shortest time with their lambs when the lambs were 40 days old, and they also showed a greater tendency to move to the flock than the Dalesbred and Jacobs. The Dalesbred ewes returned to their lambs more often than other breeds and the Jacobs tended to stay at the junction of the maze. It is suggested that maternal behaviour is strongest in Dalesbreds with young lambs and the flock tendency highest in Soays with older lambs.

Behavioural and pituitary-adrenal responses of food-deprived pigs, submitted to an intermittent food delivery schedule repeated over several weeks, were investigated.

All animals reliably displayed stereotyped activities, in the form of repeated chain pulling, during the interval between food deliveries. The temporal characteristics of this behaviour and its relation to deprivation level suggest its analogy with adjunctive activities.

Chain-pulling behaviour was accompanied by decreased pituitary-adrenal activity, as indicated by changes in plasma corticosteroid concentrations between the beginning and the end of the experimental session.

When the opportunity to engage in chain pulling was removed, corticosteroid levels did not fall below the pre-session levels. Comparisons of animals able to engage in stereotypies with animals unable to do so because the chain had been removed showed that presession levels of plasma corticosteroids were higher in the former group than in the latter, while post-session plasma corticosteroids did not differ. In addition, the opportunity to engage in adjunctive activities did not protect the animals from the activating effects of extinction on the pituitary-adrenal axis.

These data would suggest that stereotypies enable the animals to decrease excessive arousal rather than provide an extra source of stimulation.