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Smith-Funk, E. D., & Crowell-Davis, S. L. (1992). Maternal behavior of draft mares (Equus caballus) with mule foals (Equus asinus x Equus caballus). Appl. Anim. Behav. Sci., 33(2-3), 93–119.
Abstract: Draft mares and their mule foals were observed from the day of birth to Week 17 of each foal's life. The rate of nursing was recorded and the duration of nursing activity to the nearest second. The rate at which foals engaged in nursing activity varied at each age. The duration of nursing bouts varied slightly as the foals matured. Aggression was recorded during both nursing and non-nursing activity for both the mares and foals. Maternal aggression was highest during nursing activity, especially during the pre-nurse nuzzling period. Maternal aggression increased as the foals matured. Mother-directed foal aggression was primarily in response to maternal aggression. Spatial relationships between each focal dyad were recorded when the foals were upright, not nursing and when they were recumbent. Spatial relationships differed based on the foal's state. The activity in which the mare engaged while her foal was recumbent was recorded. The movements of the mares were also recorded during foal recumbency. Mares approached or maintained their distance from their recumbent foal more than they left their recumbent foal in all weeks of the study, except Week 2.
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Smith, S. F., Appleby, M. C., & Hughes, B. O. (1990). Problem solving by domestic hens: opening doors to reach nest sites. Appl. Anim. Behav. Sci., 28(3), 287–292.
Abstract: In a trial of cage designs for laying hens, eggs were discovered in dust baths where access was restricted by a closed door during the normal laying period (08:00-13:00 h). Observations showed that the hens in these dust bath treatments had developed methods of opening the doors in order to lay in the baths. Three different methods of opening were observed. An average time of 34.4 min was spent attempting to open the doors before access was finally achieved. This implies a strong nesting motivation in these hens. The proportion of eggs laid in the dust baths increased (with occasional fluctuations) over a 24-week period. Door opening is likely to have initially developed in one individual in each cage through a trial and error basis, and then have been learned by cage mates through imitation. The speed and efficiency of door opening was not found to increase with experience or time.
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Smith, S., & Goldman, L. (1999). Color discrimination in horses. Appl. Anim. Behav. Sci., 62(1), 13–25.
Abstract: Four Arabian horses and one Thoroughbred were presented with a series of two-choice color vs. gray discrimination problems. Testing was done in a stall containing a wall with two translucent panels that were illuminated from behind by light projected through color or gray filters to provide the discriminative stimuli. Horses first learned to push one of the panels in order to receive the food reward behind the positive stimulus in an achromatic light-dark discrimination task, and were then tested on their ability to discriminate between gray and four individual colors: red (617 nm), yellow (581 nm), green (538 nm), and blue (470 nm). The criterion for learning was set at 85% correct responses, and final testing for all color vs. gray discriminations involved grays of varying intensities, making brightness an irrelevant cue. Three subjects were tested with all four colors. Two of those subjects successfully reached the criterion for learning on all four color vs. gray discriminations, while the third reached criterion with red and blue, but performed at chance levels for yellow and green. A fourth horse was only tested with green and yellow, and a fifth only with blue, and both of those horses successfully reached criterion on the discriminations they attempted. With the exception of the one subject's poor performance with yellow and green, there was no significant difference between horses on any of the discrimination tasks, and no significant difference in their performance with different colors. The results suggest that horses have color vision that is at least dichromatic, although partial color-blindness may occur in some individuals.
Keywords: Horses; Vision; Color; Discrimination; Behavior
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Smith, L. A., Wells, K. L., Marion, G., Swain, D. L., & Hutchings, M. R. (). Effects of group composition on the grazing behaviour of herbivores. Anim. Behav., In Press, Corrected Proof.
Abstract: Animal behaviour is often a function of the animal's physiological state. Groups of animals will often contain individuals with a range of physiological states and the grazing behaviour of herbivores is affected by their physiological state. This study compared the grazing decisions of animals in groups of single and mixed physiological states. Using a grazing model that simulated individual herbivore behaviour in relation to environmental distributions of forage resource (grass) and parasites (faeces), we tested the hypothesis that an animal's level of parasite exposure via the faecal-oral route is affected by the composition of physiological states in the group. Four physiological states were considered: parasite-naïve, parasitized, lactating and parasite-immune animals. Baseline parasite exposure levels for each state were generated by simulating single-state groups and were compared to simulations of each of the six two-state combinations. In single-state groups parasitized animals had the least and lactating animals had the greatest levels of parasite exposure. When co-grazing with lactating animals, parasitized, immune and naïve animals increased their parasite exposure, relative to single-state groups. When co-grazing with parasitized animals, lactating, immune and naïve animals reduced their parasite exposure, relative to single-state groups. There was no difference in parasite exposure of the immune or naïve animals co-grazing together when compared to the single-state groups. These results highlight the need to recognize the impact of the individual when studying group-living animals.
Keywords: grazing; group composition; herbivore; individual behaviour; physiological state
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Smith, J. M., & Parker, G. A. (1976). The logic of asymmetric contests. Anim. Behav., 24(1), 159–175.
Abstract: A theoretical analysis is made of the evolution of behavioural strategies in contest situations. It is assumed that behaviour will evolve so as to maximize individual fitness. If so, a population will evolve an [`]evolutionarily stable strategy', or ESS, which can be defined as a strategy such that, if all members of a population adopt it, no [`]mutant' strategy can do better. A number of simple models of contest situations are analysed from this point of view. It is concluded that in [`]symmetric' contests the ESS is likely to be a [`]mixed' strategy; that is, either the population will be genetically polymorphic or individuals will be behaviourally variable. Most real contests are probably asymmetric, either in pay-off to the contestants, or in size or weapons, or in some [`]uncorrelated' fashion; i.e. in a fashion which does not substantially bias either the pay-offs or the likely outcome of an escalated contest. An example of an uncorrelated asymmetry is that between the [`]discoverer' of a resource and a [`]late-comer'. It is shown that the ESS in asymmetric contests will usually be to permit the asymmetric cue to settle the contest without escalation. Escalated contests will, however, occur if information to the contestants about the asymmetry is imperfect.
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Smith, J. E., Kolowski, J. M., Graham, K. E., Dawes, S. E., & Holekamp, K. E. (2008). Social and ecological determinants of fission-fusion dynamics in the spotted hyaena. Anim. Behav., 76(3), 619–636.
Abstract: Theory predicts that individuals living in fission-fusion societies, in which group members frequently change subgroups, should modify grouping patterns in response to varying social and environmental conditions. Spotted hyaenas, Crocuta crocuta, are long-lived carnivores that reside in permanent social groups called clans. Clans are complex, fission-fusion societies in which individual members travel, rest and forage in subgroups that frequently change composition. We studied two clans in Kenya to provide the first detailed description of fission-fusion dynamics in this species. Because social and ecological circumstances can influence the cohesiveness of animal societies, we evaluated the extent to which specific circumstances promote the formation of subgroups of various sizes. We found that cooperative defence of shared resources during interclan competition and protection from lions were cohesive forces that promoted formation of large subgroups. We also tested hypotheses suggesting factors limiting subgroup size. Mothers with small cubs avoided conspecifics, thereby reducing infanticide risk. Victims of aggression either reconciled fights or separated from former opponents to reduce the immediate costs of escalated aggression in the absence of food. As predicted by the ecological constraints hypothesis, hyaenas adjusted their grouping patterns over both short and long time scales in response to feeding competition. Crocuta were most gregarious during periods of abundant prey, joined clanmates at ephemeral kills in numbers that correlated with the energetic value of the prey and gained the most energy when foraging alone because cooperative hunting attracted numerous competitors. Overall, our findings indicate that resource limitation constrains grouping in this species.
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Slater, C., & Dymond, S. (2011). Using differential reinforcement to improve equine welfare: Shaping appropriate truck loading and feet handling. Behav. Process., 86(3), 329–339.
Abstract: Inappropriate behavior during common handling procedures with horses is often subject to aversive treatment. The present study replicated and extended previous findings using differential reinforcement to shape appropriate equine handling behavior. In Study 1, a multiple baseline across subjects design was used with four horses to determine first the effects of shaping target-touch responses and then successive approximations of full truck loading under continuous and intermittent schedules of reinforcement. Full loading responses were shaped and maintained in all four horses and occurrences of inappropriate behaviors reduced to zero. Generalization of the loading response was also observed to both a novel trainer and trailer. In Study 2, a changing criterion design was used to increase the duration of feet handling with one horse. The horse's responding reached the terminal duration criterion of 1 min and showed consistent generalization and one-week maintenance. Overall, the results of both studies support the use of applied equine training systems based on positive reinforcement for increasing appropriate behavior during common handling procedures.
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Slagsvold, T., & Viljugrein, H. (1999). Mate choice copying versus preference for actively displaying males by female pied flycatchers. Anim. Behav., 57(3), 679–686.
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Slabbert, J. M., & Rasa, O. A. E. (1997). Observational learning of an acquired maternal behaviour pattern by working dog pups: an alternative training method? Appl. Anim. Behav. Sci., 53(4), 309–316.
Abstract: German shepherd pups from untrained bitches and bitches trained in the location of narcotics were either separated from their mothers at 6 weeks (standard raised) or at 3 months of age (extended maternal care). Pups with extended maternal care which were allowed to observe their trained mothers locating and retrieving a sachet of odour-producing narcotic between the ages of 6 and 12 weeks performed the same task significantly better than non-exposed pups when tested at the age of 6 months, without further reinforcement during the interim period. This difference in performance was independent of the duration of maternal care or maternal origin of the pups and was attributed to differences in early experience acquired through observational learning.
Keywords: Dog; Learning; Parental behaviour; Narcotics
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Siniscalchi, M., Sasso, R., Pepe, A. M., Vallortigara, G., & Quaranta, A. (2010). Dogs turn left to emotional stimuli. Behav. Brain. Res., 208(2), 516–521.
Abstract: During feeding behaviour, dogs were suddenly presented with 2D stimuli depicting the silhouette of a dog, a cat or a snake simultaneously into the left and right visual hemifields. A bias to turn the head towards the left rather than the right side was observed with the cat and snake stimulus but not with the dog stimulus. Latencies to react following stimulus presentation were lower for left than for right head turning, whereas times needed to resume feeding behaviour were higher after left rather than after right head turning. When stimuli were presented only to the left or right visual hemifields, dogs proved to be more responsive to left side presentation, irrespective of the type of stimulus. However, cat and snake stimuli produced shorter latencies to react and longer times to resume feeding following left rather than right monocular visual hemifield presentation. Results demonstrate striking lateralization in dogs, with the right side of the brain more responsive to threatening and alarming stimuli. Possible implications for animal welfare are discussed.
Keywords: Dog; Laterality; Vision; Behaviour; Physiology; Cognition; Emotion; Animal welfare
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