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Zaine, L., Ferreira, C., de O. S. Gomes, M., Monti, M., Tortola, L., Vasconcellos, R. S., et al. (2011). Faecal IgA concentration is influenced by age in dogs. British Journal of Nutrition, 106(Supplement S1), S183–S186.
Abstract: Data comparing age-related alterations in faecal IgA concentrations of dogs are not available in the literature. The present study aimed to
compare the faecal concentrations of IgA in puppies, mature and senior dogs. A total of twenty-four beagle dogs were used, including eight puppies (5 months old, four females and four males), eight mature (4·6 years old, eight males) and eight senior dogs (10·6 years old, three males and five females). Fresh faecal samples were collected from each dog for three consecutive days and pooled by animal. After saline extraction, IgA content was measured by ELISA. Data were analysed by one-way ANOVA, and means were compared with Tukey’s test (P,0·05). Results showed that puppies have lower faecal IgA concentrations than mature dogs (P,0·05); senior animals presented intermediary results. The reduced faecal IgA concentration in puppies is consistent with the reduced serum and salivary IgA concentrations reported previously, suggesting a reduced mucosal immunity in this age group. Although some studies have found an increased serum IgA concentration in older dogs, this may differ from the intestinal secretion of IgA, which appears to be lower in some senior animals (four of the eight dogs studied). |
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Young, H. P. (2011). The dynamics of social innovation. Proc. Natl. Acad. Sci. U.S.A., 108(Supplement 4), 21285–21291.
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Gorodnichenko, Y., & Roland, G. (2011). Individualism, innovation, and long-run growth. Proc. Natl. Acad. Sci. U.S.A., 108(Supplement 4), 21316–21319.
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Zeitler-Feicht, M. H., Streit, S., & Dempfle, L. (2011). Automatic feeding systems for horses in group housing systems with regard to animal welfare. Part 2: Comparison of different automatic feeding systems. Tierärztl Prax, 39(G), 33–40.
Abstract: Ziel: Überprüfung der Tiergerechtheit von in der Bauweise unterschiedlichen
Futterabrufstationen für Pferde in Gruppenhaltung anhand ethologischer und physiologischer Parameter. Material und Methoden: In 32 Offenlaufställen (452 Pferde) mit computergesteuerten Abrufstationen für Kraftfutter und Heu erfolgten kontinuierliche Direktbeobachtungen für je einen 24-Stunden-Tag (Tortenstückverfahren). Erfasst wurden: Aufenthaltsdauer, Besuchshäufigkeit, Droh- und Meideverhalten im Fütterungsbereich, Blockaden sowie Herzfrequenz und Integumentverletzungen. Ergebnisse: Eine Durchlaufstation reduzierte die Zahl der Auseinandersetzungen im Fütterungsbereich signifikant. Ansonsten erhöhten die für das fressende Pferd tiergerechten Varianten (Fressstand mit Eingangssperre, ohne Austreibehilfe) Besuchshäufigkeit und Aufenthaltsdauer und steigerten somit auch die Anzahl an Drohgesten je Tier und Tag. Insgesamt betrachtet kann jedoch die Anzahl an sozionegativen Interaktionen im Fütterungsbereich der Abrufstationen als relativ gering eingestuft werden. Die Herzfrequenz lag im Warteareal bei den meisten Pferden im physiologischen Bereich (45,1 ± 12,42 Schläge/min), erhöhte sich jedoch in der Abrufstation um ca. 20 Schläge/min. Einige Tiere zeigten möglicherweise stressbedingt kurzfristig auffallend hohe Werte (≥ 100 Schläge/ min). Integumentverletzungen im Zusammenhang mit dem Fütterungssystem traten nicht auf. Der wichtigste Einflussfaktor auf die Untersuchungskriterien war der Betrieb (Fläche, Konzeption, Management). Schlussfolgerung: Durchlaufstationen sind pferdegerechter als Rücklaufstationen. Nicht tiergerecht sind Stationen mit stromführender Austreibehilfe. Weitere bauliche Unterschiede der derzeitigen Futterabrufstationen dürften eher von untergeordneter Bedeutung sein, vor allem da Flächengebot und Konzeption der Offenstallanlage sowie das Management die überprüften Kriterien zur Tiergerechtheit maßgeblich beeinflussen. Untersuchungen zur Abklärung der Ursache für die vereinzelt aufgetretenen sehr hohen Herzfrequenzwerte sollten durchgeführt werden. Objective: Comparison with regard to animal welfare of different automatic feeding systems for hay and concentrate in group housing systems for horses using parameters of ethology and physiology. Material and methods: Parameters of research comprised: duration of stay, frequency of visit, threatening behaviour with and without risk of injury, and avoiding behaviour as well as heart rate and injuries of the integument. 452 horses were observed at the feeding area of 32 run-out-sheds. Every group of horses was continuously observed following the pie chart system for 24 hours. Results: The “walk-through” station significantly reduced the number of conflicts in the feeding area, whereas those systems which are appropriate for the feeding horses (feeding station with access barrier and without stimulation device by electric shock) led to a higher frequency of visits and a longer duration of stay resulting in more threatening gestures. However, the number of negative interactions in the feeding area of the feeding systems can all together be classified as relatively insignificant. The heart rate was within the physiological range (45.1 ± 12.42 beats/min) in the waiting area, but increased by approximately 20 beats/min on average within the feeding station. Some horses showed a very high heart rate (≥ 100 beats/min) while entering the feeding station, possibly stress-related. There were no injuries of the integument associated with the feeding systems. The most important factor of the observation criteria was the individual group housing system with its different dimensions, conception and management. Conclusion: “Walk-through” stations are better than ”walk-back” stations with regard to animal welfare. Likewise, automatic feeding stations with a current-carrying stimulation device are not supportive of good welfare. The other differences between the constructions of feeding stations of present systems are probably of less importance, particularly as it was shown that the stable (management, stable area, conception) had a significant influence on the surveyed parameters. Investigations to obtain information on the cause for the sporadic occurrence of very high heart rate values should be undertaken.] |
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Cain, K. E., Rich, M. S., Ainsworth, K., & Ketterson, E. D. (2011). Two Sides of the Same Coin? Consistency in Aggression to Conspecifics and Predators in a Female Songbird. Ethology, 117(9), 786–795.
Abstract: Different forms of aggression have traditionally been treated separately according to function or context (e.g., aggression towards a conspecific vs. a predator). However, recent work on individual consistency in behavior predicts that different forms of aggression may be correlated across contexts, suggesting a lack of independence. For nesting birds, aggression towards both conspecifics and nest predators can affect reproductive success, yet the relationship between these behaviors, especially in females, is not known. Here, we examine free-living female dark-eyed juncos (Junco hyemalis) and compare their aggressive responses towards three types of simulated intruders near the nest: a same-sex conspecific, an opposite-sex conspecific, and a nest predator. We also examine differences in the strength of response that might relate to the immediacy of the perceived threat the intruder poses for the female or her offspring. We found greater aggression directed towards a predator than a same-sex intruder and towards a same-sex than an opposite-sex intruder, consistent with a predator being a more immediate threat than a same-sex intruder, followed by an opposite-sex intruder. We also found positive relationships across individuals between responses to a same-sex intruder and a simulated predator, and between responses to a same-sex and an opposite-sex intruder, indicating that individual females are consistent in their relative level of aggression across contexts. If correlated behaviors are mediated by related mechanisms, then different forms of aggression may be expressions of the same behavioral tendency and constrained from evolving independently.
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Mersmann, D., Tomasello, M., Call, J., Kaminski, J., & Taborsky, M. (2011). Simple Mechanisms Can Explain Social Learning in Domestic Dogs (Canis familiaris). Ethology, 117(8), 675–690.
Abstract: Abstract Recent studies have suggested that domestic dogs (Canis familiaris) engage in highly complex forms of social learning. Here, we critically assess the potential mechanisms underlying social learning in dogs using two problem-solving tasks. In a classical detour task, the test dogs benefited from observing a demonstrator walking around a fence to obtain a reward. However, even inexperienced dogs did not show a preference for passing the fence at the same end as the demonstrator. Furthermore, dogs did not need to observe a complete demonstration by a human demonstrator to pass the task. Instead, they were just as successful in solving the problem after seeing a partial demonstration by an object passing by at the end of the fence. In contrast to earlier findings, our results suggest that stimulus enhancement (or affordance learning) might be a powerful social learning mechanism used by dogs to solve such detour problems. In the second task, we examined whether naïve dogs copy actions to solve an instrumental problem. After controlling for stimulus enhancement and other forms of social influence (e.g. social facilitation and observational conditioning), we found that dogs’ problem solving was not influenced by witnessing a skilful demonstrator (either an unknown human, a conspecific or the dog’s owner). Together, these results add to evidence suggesting that social learning may often be explained by relatively simple (but powerful) mechanisms.
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Bartoš, L., Bartošová, J., Pluhácek, J., & Šindelárová, J. (2011). Promiscuous behaviour disrupts pregnancy block in domestic horse mares. Behavioral Ecology and Sociobiology, 65(8), 1567–1572.
Abstract: Based on questionnaires from horse breeders, we found that bringing a pregnant mare which had been mated away from home into a vicinity of a familiar male who was not the father of her foetus increased probability of pregnancy disruption. These mares aborted in 31% of cases, while none of those mated within the home stable aborted. Repeated sexual activity either by a stallion or dominant gelding from the normal home group was observed shortly after the mare came from away-mating. Pregnant mares isolated from home males by a fence were even seen soliciting them over the fence. We speculate that, once returned to the home “herd”, and introduced to familiar males, mares were more likely to terminate their pregnancy to save energy and avoid likely future infanticidal loss of their progeny by dominant male(s) of the home social group. This is a newly discovered phenomenon where a mare manipulates the male’s paternity assessment by promiscuous mating. It may explain a common increased incidence of foetal loss in domestic horses occurring in nearly 40% of pregnancies. We conclude that the common practice of transporting the mare for mating and then bringing her back to an environment with males, stallions or geldings, which did not sire the foetus, is the main cause of high percentages of pregnancy disruption in domestic horses.
Keywords: Foetal loss; Domestic horse; Bruce effect; Sexual behaviour
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Weissing, F. J. (2011). Animal behaviour: Born leaders. Nature, 474(7351), 288–289.
Abstract: Social animals face a dilemma. To reap the benefits of group living, they have to stay together. However, individuals differ in their preferences as to where to go and what to do next. If all individuals follow their own preferences, group coherence is undermined, resulting in an outcome that is unfavourable for everyone. Neglecting one's own preferences and following a leader is one way to resolve this coordination problem. But what attributes make an individual a 'leader'? A modelling study by Johnstone and Manica1 illuminates this question.
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Bartal, I. B. - A., Decety, J., & Mason, P. (2011). Empathy and Pro-Social Behavior in Rats. Science, 334(6061), 1427–1430.
Abstract: Whereas human pro-social behavior is often driven by empathic concern for another, it is unclear whether nonprimate mammals experience a similar motivational state. To test for empathically motivated pro-social behavior in rodents, we placed a free rat in an arena with a cagemate trapped in a restrainer. After several sessions, the free rat learned to intentionally and quickly open the restrainer and free the cagemate. Rats did not open empty or object-containing restrainers. They freed cagemates even when social contact was prevented. When liberating a cagemate was pitted against chocolate contained within a second restrainer, rats opened both restrainers and typically shared the chocolate. Thus, rats behave pro-socially in response to a conspecific�s distress, providing strong evidence for biological roots of empathically motivated helping behavior.
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Gesquiere, L. R., Learn, N. H., Simao, M. C. M., Onyango, P. O., Alberts, S. C., & Altmann, J. (2011). Life at the Top: Rank and Stress in Wild Male Baboons. Science, 333(6040), 357–360.
Abstract: In social hierarchies, dominant individuals experience reproductive and health benefits, but the costs of social dominance remain a topic of debate. Prevailing hypotheses predict that higher-ranking males experience higher testosterone and glucocorticoid (stress hormone) levels than lower-ranking males when hierarchies are unstable but not otherwise. In this long-term study of rank-related stress in a natural population of savannah baboons (Papio cynocephalus), high-ranking males had higher testosterone and lower glucocorticoid levels than other males, regardless of hierarchy stability. The singular exception was for the highest-ranking (alpha) males, who exhibited both high testosterone and high glucocorticoid levels. In particular, alpha males exhibited much higher stress hormone levels than second-ranking (beta) males, suggesting that being at the very top may be more costly than previously thought.
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