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Lorenz, K. (1943). Die angeborenen Formen möglicher Erfahrung. Zeitschrift für Tierpsychologie, 5(2), 235–409.
Abstract: Zusammenfassung Die vorliegende Abhandlung entspringt dem Aufgabenkreis einer jungen Arbeitsgemeinschaft zwischen Geisteswissenschaft und vergleichender Psychologie, die das wichtigste Programm des neugegründeten Philosophischen Institutes der Albertus-Universität in Königsberg darstellt. Sie ist aus der einen Abteilung dieser Anstalt, dem Institut für vergleichende Psychologie hervorgegangen. Obwohl sie eine ganze Reihe unveröffentlichter neuer Beobachtungen und Versuche enthält, stehen diese nicht genug im Mittelpunkte der Untersuchung, um eine Zusammenfassung von Ergebnissen in jener Form möglich zu machen, wie sie sonst in der induktiven Naturforschung üblich ist. Immerhin aber herrscht die induktive Denkweise in der vorliegenden Arbeit so stark vor, daß eine kurze Zusammenfassung angebracht erscbeint, wenn sie auch notgedrungen die Form einer kurzen Inhaltsangabe annehmea muß.
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Klingel H,. (1977). Observations on Social Organization and Behaviour of African and Asiatic Wild Asses (Equus africanus and E. hemionus). Z. Tierpsychol., 44, 323–331.
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Hölker, S. (2016). Typologie der deutschen Pferdehaltung – Eine empirische Studie mittels Two-Step-Clusteranalyse. Z. Agrarpolit. Landwirtsch., 94(3).
Abstract: In der deutschen Pferdebranche besteht u. a. hinsichtlich der Ausrichtung, Lage, Größe und ökonomischen Zielsetzung von Pferdehaltern eine große Heterogenität, gleichzeitig sind die Strukturen in diesem Sektor bislang kaum wissenschaftlich erfasst. Aus diesem Grund wird im vorliegenden Beitrag die Vielzahl unterschiedlicher Erscheinungsformen in der Pferdehaltung mittels einer empirisch gestützten Typologie systematisch beschrieben. Mittels einer standardisierten Onlinebefragung wurden 1.110 private, landwirtschaftliche und gewerbliche Pferdehalter sowie pferdehaltende Vereine befragt. Abgefragt wurden neben der Organisationsform, Bestandsgröße und der Ausrichtung auch Aspekte wie u. a. die Ausstattung der Anlage, die angewandten Haltungssysteme für die Pferde sowie Angaben zur zukünftige Entwicklung und den wahrgenommenen aktuellen sowie zukünftigen Herausforderungen in der Pferdehaltung. Mittels einer Clusteranalyse konnten sechs Typen herausgearbeitet werden: ländliche Hobbypferdehaltung, stadtorientierte Hobbypferdehaltung, Hobby-Zuchtpferdehaltung, Zuchtpferdehaltung, Pensionspferdehaltung und diversifizierte Pferdehaltung. Dabei sind die drei erstgenannten Typen der Liebhaberei zuzuordnen und die drei letztgenannten Typen werden mit Gewinnerzielungsabsicht betrieben. Die ermittelten Typen unterscheiden sich teilweise signifikant u. a. hinsichtlich ihrer Größe, den angewandten Haltungssystemen, der Anzahl an Betriebszweigen oder auch ihren zukünftig geplanten Entwicklungen. Die vorliegende Studie zeigt somit, dass beispielsweise bei der Entwicklung politischer Maßnahmen im Bereich der Pferdehaltung die Auswirkungen für einzelne Pferdehalter sehr unterschiedlich ausfallen können und es daher notwendig ist, die unterschiedlichen, real existierenden Betriebstypen zu berücksichtigen.
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Gehring, T. M., VerCauteren, K. C., Provost, M. L., & Cellar, A. C. (2010). Utility of livestock-protection dogs for deterring wildlife from cattle farms. Wildl. Res., 37(8), 715–721.
Abstract: Context. Livestock producers worldwide are negatively affected by livestock losses because of predators and wildlife-transmitted diseases. In the western Great Lakes Region of the United States, this conflict has increased as grey wolf (Canis lupus) populations have recovered and white-tailed deer (Odocoileus virginianus) have served as a wildlife reservoir for bovine tuberculosis (Myobacterium bovis).Aims. We conducted field experiments on cattle farms to evaluate the effectiveness of livestock-protection dogs (LPDs) for excluding wolves, coyotes (C. latrans), white-tailed deer and mesopredators from livestock pastures.Methods. We integrated LPDs on six cattle farms (treatment) and monitored wildlife use with tracking swaths on these farms, concurrent with three control cattle farms during 2005-2008. The amount of time deer spent in livestock pastures was recorded using direct observation.Key results. Livestock pastures protected by LPDs had reduced use by these wildlife compared with control pastures not protected by LPDs. White-tailed deer spent less time in livestock pastures protected by LPDs compared with control pastures not protected by LPDs.Conclusions. Our research supports the theory that LPDs can be an effective management tool for reducing predation and disease transmission. We also demonstrate that LPDs are not limited to being used only with sheep and goats; they can also be used to protect cattle.Implications. On the basis of our findings, we support the use of LPDs as a proactive management tool that producers can implement to minimise the threat of livestock depredations and transmission of disease from wildlife to livestock. LPDs should be investigated further as a more general conservation tool for protecting valuable wildlife, such as ground-nesting birds, that use livestock pastures and are affected by predators that use these pastures.
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Palme, R., Touma, C., Arias, N., Dominchin, M.N., & Lepschy, M. (2013). Steroid extraction: Get the best out of faecal samples. Wien Tierärztl Monat – Vet Med Austria, 100, 238–246.
Abstract: Faecal steroid hormone metabolites are becoming increasingly popular as parameters for reproductive functions and stress. The extraction of the steroids from the faecal matrix represents the initial step before quantification can be performed. The steroid metabolites present in the faecal matrix are of varying polarity and composition, so selection of a proper extraction procedure is essential. There have been some studies to address this complex but often neglected point. Radiolabelled steroids (e.g. cortisol or progesterone) have frequently been added to faecal samples to estimate the efficiency of the extraction procedures used. However, native, unmetabolized steroids are normally not present in the faeces and therefore the results are artifi- cial and do not accurately reflect the actual recoveries of the substances of interest. In this respect, recovery experiments based on faecal samples from radiometabolism studies are more informative. In these samples, the metabolite content accurately reflects the mixture of metabolites present in the given species. As a result, it is possible to evaluate different extraction methods for use with faecal samples. We present studies on sheep, horses, pigs, hares and dogs that utilized samples containing naturally metabolized, 14C-labelled steroids. We recommend extracting faecal steroids by simply suspending the faeces in a high percentage of a primary alcohol (for glucocorticoid metabolites 80% aqueous methanol proved best suited for virtually all mammalian species tested so far). Not only does the procedure significantly increase the total amount of recovered radioactivity, it also increases the percentage of unconjugated metabolites, which are more likely to be recognized by the antibodies used in various immunoassays. The advantages of this extraction procedure are clear: it is very easy to use (no evaporation step is needed), it yields high recoveries and variation based on the extraction procedure is reduced to a minimum.
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Palme, R., Touma, C., Arias, N., Dominchin, M. F., & Lepschy, M. (2012). Steroid extraction: Get the best out of faecal samples. Vet. Med. Austria, 100, 238–246.
Abstract: Faecal steroid hormone metabolites are becoming increasingly popular as parameters for reproductive functions and stress. Theextraction of the steroids from the faecal matrix represents the initial step before quantification can be performed. The steroid metabolites present in the faecal matrix are of varying polarity and composition, so selection of a proper extraction procedure is essential. There have been some studies to address this complex but often neglected point. Radiolabelled
steroids (e.g. cortisol or progesterone) have frequently been added to faecal samples to estimate the efficiency of the extraction procedures used. However, native, unmetabolized steroids are normally not present in the faeces and therefore the results are artificial and do not accurately reflect the actual recoveries of the substances of interest. In this respect, recovery experiments based on faecal samples from radiometabolism studies are more informative. In these samples, the metabolite content accurately reflects the mixture of metabolites present in the given species. As a result, it is possible to evaluate different extraction methods for use with faecal samples. We present studies on sheep, horses, pigs, hares and dogs that utilized samples containing naturally metabolized, 14C-labelled steroids. |
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Palm, A. - K. E., Wattle, O., Lundström, T., & Wattrang, E. (2016). Secretory immunoglobulin A and immunoglobulin G in horse saliva. Vet. Immunol. Immunolpathol., 180, 59–65.
Abstract: This study aimed to increase the knowledge on salivary antibodies in the horse since these constitute an important part of the immune defence of the oral cavity. For that purpose assays to detect horse immunoglobulin A (IgA) including secretory IgA (SIgA) were set up and the molecular weights of different components of the horse IgA system were estimated. Moreover, samples from 51 clinically healthy horses were tested for total SIgA and IgG amounts in saliva and relative IgG3/5 (IgG(T)) and IgG4/7 (IgGb) content were tested in serum and saliva. Results showed a mean concentration of 74μg SIgA/ml horse saliva and that there was a large inter-individual variation in salivary SIgA concentration. For total IgG the mean concentration was approx. 5 times lower than that of SIgA, i.e. 20μg IgG/ml saliva and the inter-individual variation was lower than that observed for SIgA. The saliva-serum ratio for IgG isotypes IgG3/5 and IgG4/7 was also assessed in the sampled horses and this analysis showed that the saliva-serum ratio of IgG4/7 was in general approximately 4 times higher than that of IgG3/5. The large inter-individual variation in salivary SIgA levels observed for the normal healthy horses in the present study emphasises the need for a large number of observations when studying this parameter especially in a clinical setting. Moreover, our results also indicated that some of the salivary IgG does not originate from serum but may be produced locally. Thus, these results provide novel insight, and a base for further research, into salivary antibody responses of horses.
Keywords: Equine; Secretory IgA; IgG; Saliva; Mucosal immunity
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Amodio, P., Boeckle, M., Schnell, A. K., Ostojic, L., Fiorito, G., & Clayton, N. S. (2018). Grow Smart and Die Young: Why Did Cephalopods Evolve Intelligence? Trends. Ecol. Evol., .
Abstract: Intelligence in large-brained vertebrates might have evolved through independent, yet similar processes based on comparable socioecological pressures and slow life histories. This convergent evolutionary route, however, cannot explain why cephalopods developed large brains and flexible behavioural repertoires: cephalopods have fast life histories and live in simple social environments. Here, we suggest that the loss of the external shell in cephalopods (i) caused a dramatic increase in predatory pressure, which in turn prevented the emergence of slow life histories, and (ii) allowed the exploitation of novel challenging niches, thus favouring the emergence of intelligence. By highlighting convergent and divergent aspects between cephalopods and large-brained vertebrates we illustrate how the evolution of intelligence might not be constrained to a single evolutionary route.
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Rosati, A. G. (2017). Foraging Cognition: Reviving the Ecological Intelligence Hypothesis. Trends in Cognitive Sciences, 21(9), 691–702.
Abstract: What are the origins of intelligent behavior? The demands associated with living in complex social groups have been the favored explanation for the evolution of primate cognition in general and human cognition in particular. However, recent comparative research indicates that ecological variation can also shape cognitive abilities. I synthesize the emerging evidence that ?foraging cognition? ? skills used to exploit food resources, including spatial memory, decision-making, and inhibitory control ? varies adaptively across primates. These findings provide a new framework for the evolution of human cognition, given our species? dependence on costly, high-value food resources. Understanding the origins of the human mind will require an integrative theory accounting for how humans are unique in both our sociality and our ecology.
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Taberlet, P., Waits, L. P., & Luikart, G. (1999). Noninvasive genetic sampling: look before you leap. Trends Ecol. Evol, 14(8), 323–327.
Abstract: Noninvasive sampling allows genetic studies of free-ranging animals without the need to capture or even observe them, and thus allows questions to be addressed that cannot be answered using conventional methods. Initially, this sampling strategy promised to exploit fully the existing DNA-based technology for studies in ethology, conservation biology and population genetics. However, recent work now indicates the need for a more cautious approach, which includes quantifying the genotyping error rate. Despite this, many of the difficulties of noninvasive sampling will probably be overcome with improved methodology.
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