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Walther, F. R. (1991). On herding behavior. Appl. Anim. Behav. Sci., 29(1-4), 5–13.
Abstract: Herding behavior in ungulates is executed mainly by males. There are several forms of herding: guarding a single estrous female; rounding up a bunch of females during the rutting season; territorial herding by which a male keeps females inside his territory; herding of a moving, permanent, harem group; social herding in which group members of both sexes are herded by one dominant male. When put into this sequence, a phenotypical trend is illustrated, leading from an intimate connection of herding with mating behavior toward an increasing independence from sexual behavior and culminating in a complete socialization of herding. Aspects and problems of herding behavior are the recognition of, and the animal's respect for, partners in gregarious species; the animal “taking offense” at activities of others which deviate from its own activity; the active coordination and synchronization of group activities; the use of, and the effects of, threat, dominance and courtship displays in herding; the possibility of substitution among expressive displays in relation to partners of different sex; the communicative function of the animal's orientation relative to the partner; social hierarchy and leadership in a group; the possibility of interspecific herding, particularly in man-animal relationships, which is closely linked to the process of domestication.
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Beauchamp, G., & Kacelnik, A. (1991). Effects of the knowledge of partners on learning rates in zebra finches Taeniopygia guttata. Anim. Behav., 41(2), 247–253.
Abstract: Many interpretations of the adaptive value of group living involve tranfer of knowledge. However, according to learning theory, being in a pair with a knowledgeable partner can have paradoxical consequences. Obtaining food by following a skilled companion may reduce the ability of naive individuals to learn about clues that signal the occurrence of food. This study examined the relation between learning and following in paris of zebra finches. Knowledgeable partners were trained to obtain food from a computer-controlled dispenser by using the information provided by a signal. For non-knowledgeable partners, the signal was irrelevant and could not be used to predict foraging opportunities. The rate of learning about the signal by naive birds that shared the experience of either knowledgeable or nonknowledgeable tutors was then examined. Naive birds learned more slowly as a result of being in a pair with a knowledgeable than a non-knowledgeable partner. Well-informed mates acted as a reliable cue to predict foraging opportunities, and thus overshadowed the independent signal. The knowledge of a partner influences learning rates in naive individuals, but in the opposite direction to that predicted by earlier accounts of learning in social contexts.
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Garott, R. A. (1991). Sex Ratios and Differential Survival of Feral Hors. J Anim Ecol, 60(3), 929–936.
Abstract: (1) Sex and age data were collected on 60 111 feral horses (Equus caballus L.) removed from eighty-nine areas in Nevada, Wyoming, and Oregon between 1976 and 1987. (2) Sex ratios of young seldom differed from parity; however, sex ratios of adults were commonly skewed toward females. No evidence of differential capture probability between adult males and females could be detected; therefore, skewed adult sex ratios were attributed to differential survival. (3) Age-specific trends in sex ratios indicated that the proportion of males steadily decreased from near parity in foals, to lows of 0.61-0.77 in the 4-5-year age-classes. The trend then reversed with males becoming predominant (1.08-1.36) in the > 10 years age-class. (4) Population simulations suggest that survival diffentials of 0.05-0.07, favouring females to 4 years of age, and 0.02-0.04 favouring males in older age-classes were required to mimic observed age-specific sex ratio changes. To obtain the high proportion of males in the > 10-years age-class, onset of senescence also had to be earlier for females. (5) Causes for differential survival in the immature age-classes are uncertain, but may relate to behavioural or metabolic differences between the sexes. Differential survival between adult males and females is attributed to differences in the energetic costs of reproduction and disparity in their reproductive life spans.
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Duncan, I. J., & Petherick, J. C. (1991). The implications of cognitive processes for animal welfare. J. Anim Sci., 69(12), 5017–5022.
Abstract: In general, codes that have been designed to safeguard the welfare of animals emphasize the importance of providing an environment that will ensure good health and a normal physiological and physical state, that is, they emphasize the animals' physical needs. If mental needs are mentioned, they are always relegated to secondary importance. The argument is put forward here that animal welfare is dependent solely on the cognitive needs of the animals concerned. In general, if these cognitive needs are met, they will protect the animals' physical needs. It is contended that in the few cases in which they do not safeguard the physical needs, it does not matter from a welfare point of view. The human example is given of being ill. It is argued that welfare is only adversely affected when a person feels ill, knows that he or she is ill, or even thinks that he or she is ill, all of which processes are cognitive ones. The implications for welfare of animals possessing certain cognitive abilities are discussed. For example, the extent to which animals are aware of their internal state while performing behavior known to be indicative of so-called states of suffering, such as fear, frustration, and pain, will determine how much they are actually suffering. With careful experimentation it may be possible to determine how negative they feel these states to be. Similarly, the extent to which animals think about items or events absent from their immediate environment will determine how frustrated they are in the absence of the real item or event but in the presence of the cognitive representation.
Keywords: *Animal Welfare; Animals; Animals, Domestic/*psychology; *Cognition
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Curtis, S. E., & Stricklin, W. R. (1991). The importance of animal cognition in agricultural animal production systems: an overview. J. Anim Sci., 69(12), 5001–5007.
Abstract: To describe and then fulfill agricultural animals' needs, we must learn more about their fundamental psychological and behavioral processes. How does this animal feel? Is that animal suffering? Will we ever be able to know these things? Scientists specializing in animal cognition say that there are numerous problems but that they can be overcome. Recognition by scientists of the notion of animal awareness has been increasing in recent years, because of the work of Griffin and others. Feeling, thinking, remembering, and imagining are cognitive processes that are factors in the economic and humane production of agricultural animals. It has been observed that the animal welfare debate depends on two controversial questions: Do animals have subjective feelings? If they do, can we find indicators that reveal them? Here, indirect behavioral analysis approaches must be taken. Moreover, the linear additivity of several stressor effects on a variety of animal traits suggests that some single phenomenon is acting as a “clearinghouse” for many or all of the stresses acting on an animal at any given time, and this phenomenon might be psychological stress. Specific situations animals may encounter in agricultural production settings are discussed with respect to the animals' subjective feelings.
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Chapais, B., Girard, M., & Primi, G. (1991). Non-kin alliances, and the stability of matrilineal dominance relations in Japanese macaques. Anim. Behav., 41(3), 481–491.
Abstract: Alliances among kin play a major role in a female's acquisition of her mother's dominance rank in many species of cercopithecines. It is noteworthy, however, that kin rarely form coalitions to challenge females from higher-ranking matrilines, and that matrilineal hierarchies are remarkably stable. One possible reason for the rarity of destabilizing coalitions is that members of high-ranking matrilines form alliances against lower ranking ones. In this paper the patterning of aggressive support among non-kin, and its effect on the stability of rank relations are analysed in a captive group of Japanese macaques, Macaca fuscata, composed of three unrelated matrilines. Analysis of the distribution of non-kin interventions in conflicts between matrilines over a 52-month period revealed a clear pattern of preferential support between the two dominant matrilines against the third-ranking one. This pattern was confirmed experimentally. Any member of the two dominant matrilines was unable, individually, to maintain its rank above the third-ranking matriline, but was able to do so in the presence of the other dominant matriline. Non-kin alliances appear to prevent subordinate females from challenging higher ranking females through revolutionary coalitions (formed among subordinates) or through bridging coalitions (formed among individuals ranking above and below the target). Non-kin support is interpreted in terms of cooperation versus reciprocal altruism.
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Kendrick, K. M. (1991). How the sheep's brain controls the visual recognition of animals and humans. J. Anim Sci., 69(12), 5008–5016. |
Marinier, S. L., & Alexander, A. J. (1991). Selective grazing behaviour in horses: development of methodology and preliminary use of tests to measure individual grazing ability. Appl. Anim. Behav. Sci., 30(3-4), 203–221.
Abstract: Methods are described to assess horses' selective grazing ability that includes choosing, sorting and the adaptive value of this behaviour. Choosing ability was tested by the experimenter presenting pairs of cut plant species that were then alternated at each presentation until the test horse had taken three bites of one of the plant pair. The results were analysed in relation to five measures of choosing behaviour: (1) the strength of the choice; (2) correspondence between first bite and the final choice; (3) constancy of the choice over a number of trials; (4) the comparison of the horses' ranking of the species over a number of trials; (5) the constancy of the linear arrangement of the plants over a number of trials. Sorting ability was tested using two methods. A mixture of two plant species was presented either in a clamp or loose in a trough. Results were based on number and weight of plant residues. The adaptive value of the behaviour related to the bitterness of toxic plants. This bitterness was represented in testing by quinine sulphate and a poisonous Senecio species. An extremely bitter substance “Bitrex” was also used in this context but was totally accepted by the horses. The horses' reactions to these substances were monitored using a behavioural score chart. The results from 12 horses revealed that the horses differed individually in their grazing ability. On this basis, the horses were classified as efficient, semi-efficient, or inefficient grazers. This finding has practical implications in deciding which horses may safely graze on pastures infested with toxic plants.
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Boesch, C. (1991). Teaching among wild chimpanzees. Anim. Behav., 41(3), 530–532. |
Mal, M. E., Friend, T. H., Lay, D. C., Vogelsang, S. G., & Jenkins, O. C. (1991). Behavioral responses of mares to short-term confinement and social isolation. Appl. Anim. Behav. Sci., 31(1-2), 13–24.
Abstract: Thirty-six mares, blocked by age and temperament score, were assigned to one of three treatment groups: pasture (P); confinement stalls (C), allowing social contact; isolation stalls (ISS), allowing no contact with conspecifics. After 48 h on treatment, the mares were observed in situ for 1 h. Medium temperament and highly reactive ISS mares spent more time eating grain (P<0.01) and exhibited more grain-eating bouts (P<0.03) than P and C mares. Calm P mares had longer forage-eating bouts than C and ISS mares (P<0.02). During a 15 min open-field test in a 23 m x 23 m pen after 72 h on treatment, ISS mares traveled farther (P<0.005) than C and P mares, spent more total time trotting (P<0.01) than C and P mares, and exhibited a greater number of trotting bouts (P<0.01) than both C and P mares. Isolated mares spent less total time standing during the open-field test than C (P<0.05) and P (P<0.01) mares, but exhibited a greater number of standing bouts than C (P<0.05) and P (P<0.01) mares. Isolated mares also exhibited a greater number of total activity bouts (P<0.01) during the open-field test than both C and P mares; P mares also exhibited fewer activity bouts than C mares (P<0.1). Results indicate that mares kept in confined and isolated environments showed greater motivation for movement and performance of a greater number of activities than those maintained on pasture with conspecifics.
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