Applied Animal Ethology最新文献

A study of drinking behaviour of individual broiler breeder chicks from hatching to 5 weeks of age was conducted. The action patterns involved in obtaining a drink as well as water consumption were described quantitatively and qualitatively. Over the experimental period, the action patterns of drinking were modified gradually. Marked changes in immersion angle, swallowing angle and distance from the waterer were evident. All birds made progressively fewer trips to the waterer to take a larger number of higher volume drinks. This information is essential for future design of improved watering equipment to better complement the natural drinking behaviour of broiler chickens.

The characteristics of sites used by feral goats for parturition and by neonates during lying-out were examined. Parturition and lying-out sites were concentrated in areas of high use by the female herd, and were closer to a traditional night-camp than expected by chance. Parturition sites were more likely to have overhead cover, be adjacent to a vertical object and have lower wind velocity than controls. Lying-out sites differed from controls in: slope; substrate; proximity to a vertical object; cover; and by having lower wind velocity and lower light intensity. The characteristics selected for parturition and lying-out sites seem to offer protection to females and their neonates from the environment and from potential predators.

We observed a group of captive wild pigs to determine how agonistic encounters vary as a function of preceding activities and with the availability and distribution of resources. Data are presented supporting previous competition hypotheses. The frequency and intensity of encounters was highest during competition for resources that were limited and defendable. Activities associated with limited but undefendable resources were followed by fewer encounters which were of lower intensity. When unlimited and undefendable resources were involved, agonistic encounters were infrequent. Comparisons with earlier work show that patterns of agonistic behavior in groups of Sus scrofa, regardless of the environmental setting, are not simply related to the preceding activity per se, but are related systematically to the availability and distribution of resources associated with that activity. A short-term decrease in the tendency of one male to displace its rank neighbor, not encompassed by familiar notions of rank-neighbor relations, was discovered. A previously undescribed visual display used to prevent or inhibit aggression was observed.

The breeding behavior of free-ranging dogs (Canis familiaris) was studied in Newark New Jersey, in the summer of 1978 and the winter of 1978–1979. The presence of an estrous female in an area led to increased aggression and hierarchy formation among males as they congregated around the female and attempted to mate. Data on estrous group dynamics, as well as evidence for female mate-selection, were gathered.

Males were categorized as either familiar or unfamiliar to the female, based on the proximity of their home-range core areas. Familiarity appeared to be a critical factor in mating success, as unfamiliar males were never observed mating; they generally remained in the estrous group for shorter periods of time and suffered a disproportionate number of attacks in comparison to familiar males.

While the consequences of such mate-selection are not clear, it is suggested that the observed behavior may be a vestige from a monogamous ancestor in which long-term pair bonds and paternal care predispose the female to choose males about whom she has more information. A shift to promiscuity in domestic dogs should not imply indiscriminate mating.

The ability of ewes and their lambs to keep together during the first day or two of life, when the mother—offspring bond is consolidating, was examined in fine-wool Merino, Dorset Horn and Crossbred (Border Leicester × Merino ewes mated to a Suffolk ram) sheep, lambing on a sparse pasture in the Armidale district of N.S.W., and in a Romney flock, lambing on good pasture in the Mangakino district of New Zealand. Ewes in the N.Z. flock had been selected for their ability to rear more than one lamb.

46% of the twin-bearing Merinos became permanently separated from a lamb, mostly on the day after giving birth, and in at least 54% of these cases these was no obvious precipitating factor such as birth difficulties or interference by other sheep. In addition, a further 34% of twin-bearing Merinos experienced temporary separation from one lamb. By contrast, in the other flocks, permanent separations were 17, 0 and 8%, respectively, and some precipitating factor could always be identified. Few separations were associated with human interference.

The sheep at Armidale moved from the birth-site much more rapidly than the Romneys (means of 2 h versus 6.5 h), possibly due to sparse pasture conditions. In the Merinos, the proportion of separations decreased as the time that ewes remained near the birth-site increased. The observations indicate that fine-wool Merino ewes are slow to recognize the size of their litters and inherently poor at maintaining contact with more than one lamb in the neonatal period.

Free-ranging domestic dogs (Canis familiaris) in Newark, New Jersey (U.S.A.), were studied during summer (1978) and winter (1978–1979) months. Population densities of approximately 400 dogs per square mile and a sex ratio of 3 males: 1 female were found for each of three study areas. Free-ranging dogs were typically large, owned individuals; strays were a monority. Of four different group types identified in this study (familiar, unfamiliar, people-mediated and estrous), the first three are described. The social organization during non-breeding periods was characterized by a majority of solitary individuals. The relatively few groups observed rarely contained more than two individuals. Familiarity between dogs was the primary basis of sociality, although the distance a dog was from its home-site, its body size, age and ownership status also influenced social behavior. There was no seasonal variation in these patterns. Aggression was rare and mutual avoidance was the primary spacing mechanism. However, of those agonistic interactions that did occur, unfamiliar dogs were involved 5–15 times more frequently than familiar dogs.

Home-range movements of individuals were largely restricted to areas around the home-site. Home-range size was correlated to a dog's ownership status much more than body size. There was no evidence of territoriality.

Resources such as food and shelter influenced the social organization by concentrating individuals in areas where these were available. Major, predictable changes in available food had no effect on social behavior. Likewise, environmental parameters such as human presence and weather conditions generally influenced dog behavior indirectly.

Two experiments were conducted on captive dingoes (Canis familiaris dingo) and New Guinea wild dogs (Canis familiaris hallstromi) to evaluate: (1) whether these dogs will acquire conditioned food aversions; and (2) to investigate the use of thiabendazole for establishing illness-based food aversions. Of 14 dogs fed thiabendazole-treated lamb, only one continued to consume untreated lamb meat. All 5 dogs which were fed lamb on the same schedules as the treatment animals continued to consume all of the lamb presented. Clearly, thiabendazole produces conditioned taste aversions, and further research for application to canine damage control problems seems justified.

An electronic monitoring instrument was developed to record the amount of time during which cow cubicles are occupied daily by recumbent cows. The instrument also recorded the number of times the cubicle was occupied for periods of greater than 5 min. The equipment was used to assess the occupancy of lipless concrete floored cubicles having different floor gradients. Cubicles of standard length 2.25 m, but with falls of 50, 100 or 150 mm, were occupied for 520, 499 and 399 ± 22.5 min/day, respectively. The 150-mm cubicles were occupied for significantly shorter periods per day than either the 100-mm (P < 0.01) or 50-mm (P < 0.001) cubicles. There was a tendency for the average duration of an occupation incident to decrease as the floor gradient increased.