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Kulikova, E. E., Isaeva, A. S., Rotkina, A. S., Manykin, A. A., & Letarov, A. V. (2007). Diversity and dynamics of bacteriophages in horse feces. Microbiology, 76(2), 271–278.
Abstract: The complex cellulolytic microbial community of the horse intestines is a convenient model for studying the ecology of bacteriophages in natural habitats. Unlike the rumen of the ruminants, this community of the equine large intestine is not subjected to digestion. The inner conditions of the horse gut are much more stable in comparison to other mammals, due to the fact that the horse diet remains almost unchanged and the intervals between food consumption and defecation are much shorter than the whole digestive cycle. The results of preliminary analysis of the structure and dynamics of the viral community of horse feces, which combines direct and culture methods, are presented. In horse fecal samples, we detected more than 60 morphologically distinct phage types, the majority of which were present as a single phage particle. This indicates that the community includes no less than several hundreds of phage types. Some phage types dominated and constituted 5-11% of the total particle count each. The most numerous phage type had an unusual morphology: the tails of its members were extremely long (about 700 nm), flexible, and irretractable, while their heads were 100 nm in diameter. Several other phage types with similar but not identical properties were detected. The total coliphage plaque count of the samples taken from three animals revealed significant fluctuations in the phage titers. During the observation time, the maximum titer ranged within four orders of magnitude (10(3)-10(7) plaque forming units (PFU)/g); the minimum titer ranged within two orders of magnitude. The samples contained two to five morphologically distinct and potentially competitive coliphage types, specific to a single Escherichia coli strain.
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Clauss, M., Castell, J. C., Kienzle, E., Schramel, P., Dierenfeld, E. S., Flach, E. J., et al. (2007). Mineral absorption in the black rhinoceros (Diceros bicornis) as compared with the domestic horse. J Anim Physiol Anim Nutr (Berl), 91(5-6), 193–204.
Abstract: To test whether mineral recommendations for horses are likely to guarantee adequate mineral provision for black rhinoceroses (Diceros bicornis), we investigated the apparent absorption (aA) of macro- and microminerals in eight black rhinoceroses from three zoological institutions in a total of 32 feeding trials with total faecal collection, with additional data from three unpublished studies (18 feeding trials). Feeds and faeces were analysed for Ca, P, Mg, Na, K, Fe, Mn, Cu, Zn and Co. The resulting aA coefficients, and the linear relationships of apparently absorbable dietary mineral content to total dietary mineral content [per 100 g dry matter (DM)], were compared with data for domestic horses. Rhinoceroses had significantly higher aA coefficients for Ca and Mg (because of a higher calculated 'true' absorption), and lower ones for Na and K (because of calculated higher endogenous faecal losses). High absorption efficiency for divalent cations is hypothesized to be an adaptation to a natural diet of particularly high Ca:P ratio (approximately 14:1); an effective removal of Ca from the ingesta guarantees sufficient P availability at the fermentation site in the hindgut. Higher faecal losses of Na and K are hypothesized to be linked to a higher faecal bulk per DM intake in black rhinoceroses as compared with horses because of a generally lower digestive efficiency. There were no relevant differences in the absorption patterns of microminerals. In particular, there were no discernable differences in Fe absorption within the rhinoceroses for diets with and without tannin supplementation. Several of the zoo diets assessed in this study were deficient in Cu, Mn or Zn, and most contained excessive levels of Fe when compared with horse requirements. The findings of this study indicate that differences in mineral absorption between occur even between species of similar digestive anatomy; that in particular, Ca absorption might vary between hindgut fermenters with Ca:P ratio in their natural diet; that Na might be a particularly limiting factor in the ecology of free-ranging rhinoceroses; that moderate doses of tannins do not seem to markedly influence mineral absorption; and that diets for captive animals should contain adequate, but not excessive mineral levels.
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Pickering, C. M., & Hill, W. (2007). Impacts of recreation and tourism on plant biodiversity and vegetation in protected areas in Australia. J Environ Manage, .
Abstract: This paper reviews recent research into the impact of recreation and tourism in protected areas on plant biodiversity and vegetation communities in Australia. Despite the international significance of the Australian flora and increasing visitation to protected areas there has been limited research on recreational and tourism impacts in Australia. As overseas, there are obvious direct impacts of recreation and tourism such as clearing of vegetation for infrastructure or damage from trampling, horse riding, mountain biking and off road vehicles. As well, there are less obvious but potentially more severe indirect impacts. This includes self-propagating impacts associated with the spread of some weeds from trails and roads. It also includes the severe impact on native vegetation, including many rare and threatened plants, from spread of the root rot fungus Phytopthora cinnamomi. This review highlights the need for more recreational ecology research in Australia.
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Schmidt, R., Amrhein, V., Kunc, H. P., & Naguib, M. (2007). The day after: effects of vocal interactions on territory defence in nightingales. T. J. Anim. Ecol., 76(1), 168–173.
Abstract: 1. Models on territory acquisition and tenure predict that territorial animals benefit by adjusting territorial defence behaviour to previous challenges they had experienced within the socially complex environment of communication networks. 2. Here, we addressed such issues of social cognition by investigating persisting effects of vocal contests on territory defence behaviour in nightingales Luscinia megarhynchos (Brehm). 3. Using interactive playback during nocturnal song of subjects, a rival was simulated to countersing either aggressively (by song overlapping) or moderately (by song alternating) from outside the subjects' territory. Thereby, the time-specific singing strategy provided an experimentally controlled source of information on the motivation of an unfamiliar rival. 4. Expecting that nightingales integrate information with time, the same rival was simulated to return as a moderately singing intruder on the following morning. 5. The results show that the vigour with which male nightingales responded to the simulated intrusion of an opponent during the day depended on the nature of the nocturnal vocal interaction experienced several hours before. 6. Males that had received the song overlapping playback the preceding night approached the simulated intruder more quickly and closer and sang more songs near the loudspeaker than did males that had received a song alternating playback. 7. This adjustment of territory defence strategies depending on information from prior signalling experience suggests that integrating information with time plays an important part in territory defence by affecting a male's decision making in a communication network.
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Overli, O., Sorensen, C., Pulman, K. G. T., Pottinger, T. G., Korzan, W., Summers, C. H., et al. (2007). Evolutionary background for stress-coping styles: relationships between physiological, behavioral, and cognitive traits in non-mammalian vertebrates. Neurosci Biobehav Rev, 31(3), 396–412.
Abstract: Reactions to stress vary between individuals, and physiological and behavioral responses tend to be associated in distinct suites of correlated traits, often termed stress-coping styles. In mammals, individuals exhibiting divergent stress-coping styles also appear to exhibit intrinsic differences in cognitive processing. A connection between physiology, behavior, and cognition was also recently demonstrated in strains of rainbow trout (Oncorhynchus mykiss) selected for consistently high or low cortisol responses to stress. The low-responsive (LR) strain display longer retention of a conditioned response, and tend to show proactive behaviors such as enhanced aggression, social dominance, and rapid resumption of feed intake after stress. Differences in brain monoamine neurochemistry have also been reported in these lines. In comparative studies, experiments with the lizard Anolis carolinensis reveal connections between monoaminergic activity in limbic structures, proactive behavior in novel environments, and the establishment of social status via agonistic behavior. Together these observations suggest that within-species diversity of physiological, behavioral and cognitive correlates of stress responsiveness is maintained by natural selection throughout the vertebrate sub-phylum.
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Cohen, J. (2007). Animal behavior. The world through a chimp's eyes (Vol. 316). |
Morell, V. (2007). Nicola Clayton profile. Nicky and the jays (Vol. 315). |
Koski, S. E., Koops, K., & Sterck, E. H. M. (2007). Reconciliation, relationship quality, and postconflict anxiety: testing the integrated hypothesis in captive chimpanzees. Am. J. Primatol., 69(2), 158–172.
Abstract: Reconciliation is a conflict resolution mechanism that is common to many gregarious species with individualized societies. Reconciliation repairs the damaged relationship between the opponents and decreases postconflict (PC) anxiety. The “integrated hypothesis” links the quality of the opponents' relationship to PC anxiety, since it proposes that conflicts among partners with high relationship quality will yield high levels of PC anxiety, which in turn will lead to an increased likelihood of reconciliation. We tested the integrated hypothesis in captive chimpanzees (Pan troglodytes) in the Arnhem Zoo, The Netherlands. We applied the standard PC/matched control (MC) method. Our results mostly support the integrated hypothesis, in that more valuable and compatible partners (i.e., males and frequent groomers) reconciled more often than less valuable and weakly compatible partners (i.e., females and infrequent groomers). In addition, PC anxiety was higher after conflicts among males than among females. Emotional arousal thus appears to be a mediator facilitating reconciliation. However, in contrast to the predictions derived from the integrated hypothesis, PC anxiety appeared only in aggressees, and not in aggressors, of conflicts. This suggests that while relationship quality determines PC anxiety, it is dependent on the role of the participants in the conflict.
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Nogueira, S. S. da C., Nogueira-Filho, S. L. G., Bassford, M., Silvius, K., & Fragoso, J. M. V. (2007). Feral pigs in Hawai`i: Using behavior and ecology to refine control techniques. Appl. Anim. Behav. Sci., 108(1-2), 1–11.
Abstract: Early Polynesians settlers were the first to introduce pigs to the Hawaiian Islands. Later Captain Cook brought European pigs during his first voyage to Hawai`i. Many other importations have followed. Animals from these introductions became feral and dispersed throughout the islands. Free-ranging pigs are now considered pests with negative impacts on some native biota. Several methods to control the ecological damage attributed to pigs have been adopted, such as fencing, hunting, live trapping and poisoning. However, the absence of behavioral knowledge in current control programs has resulted in inefficient management of this species. Therefore, the feral pig problem continues, and what before was almost strictly an agricultural and conservation concern has now become an urban problem as well. The aim of this study is to describe the state of knowledge on feral pig behavior in the Hawaiian Islands, introducing potential management approaches derived from the principles of behavioral ecology. Considering behavioral aspects of feral pig ecology, such as cognition and communication could help improve capture techniques, keep feral pigs away from urban areas and begin to resolve human-wildlife conflicts.
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Watanabe, S. (2007). How animal psychology contributes to animal welfare. Appl. Anim. Behav. Sci., 106(4), 193–202.
Abstract: This article explores the contribution of animal psychology to animal welfare. Since animal welfare includes subjective welfare, it is crucial to know the subjective world of animals. Analysis of the concept of anthropomorphism is particularly important because it is a basic idea of animal ethics. The history of animal psychology, focusing on anthropomorphism and behaviourism, is briefly described, and then measurement of the subjective experience of animals in two ways, namely animal cognition and pleasure or reinforcing effects, is reported. Finally, it is suggested that animal welfare is not a permanently fixed idea, but a socially constructed one that can be changed. To gain widespread agreement about a socially constructed idea, it is important to know in which circumstances ordinary people employ metaphorical extension to an understanding of animal behaviour. In other words, a survey of “folk animal psychology” is important in order to establish a consensus about animal welfare.
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