| Home | << 1 2 3 4 5 6 >> |
|
Zlatanova, D., Ahmed, A., Valasseva, A., & Genov, P. (2014). Adaptive Diet Strategy of the Wolf (Canis lupus L.) in Europe: a Review. Acta zool. bulg., 66(4), 439–452.
Abstract: The diet strategy of the wolf in Europe is reviewed on the basis of 74 basic and 14 additional literature
sources. The comparative analysis reveals clear dependence on the latitude (and, therefore, on the changing environmental conditions) correlated with the wild ungulate abundance and diversity. Following a geographic pattern, the wolf is specialised on different species of ungulates: moose and reindeer in Scandinavia, red deer in Central and Eastern Europe and wild boar in Southern Europe. Where this large prey is taken, the roe deer is hunted with almost the same frequency in every region. The wolf diet in Europe shows two ecological adaptations formed by a complex of variables: 1. Wolves living in natural habitats with abundance of wild ungulates feed mainly on wild prey. 2. In highly anthropogenic habitats, with low abundance of wild prey, wolves feed on livestock (where husbandry of domestic animals is available) and take also a lot of plant food, smaller prey (hares and rodents) and garbage food. The frequency of occurrence of wild ungulates in the diet of wolves in North Europe varies from 54.0% in Belarus to 132.7% in Poland, while that of livestock is in the range from 0.4% in Norway to 74.9% in Belarus. In South Europe, the frequency of occurrence of wild prey varies from 0% in Italy and Spain to 136.0% in Italy, while of domestic ungulates ranges between 0% and 100% in Spain. The low density or lack of wild prey triggers the switch of the wolf diet to livestock, plant food (32.2-85% in Italy) or even garbage (up to 41.5% in Italy). |
|
Benz, B., Münzing, C., Krueger, K., & Winter, D. (2014). Ethologische Untersuchung von Heuraufen in der Pferdehaltung [Ethological investigation of hayracks in equine husbandry]. Landtechnik, 69(5), 239–244.
Abstract: Eine tiergerechte, physiologisch und anatomisch auf die Bedürfnisse der Pferde ausgerichtete
Raufutterversorgung sollte die Kaubedürfnisse und die Beschäftigungszeiten von Pferden ausreichend berücksichtigen. Daher – und auch aufgrund des bestehenden Kostendrucks bei Raufutter – steigt das Interesse an Raufutterraufen, durch die möglicherweise die Futteraufnahmezeiten verlängert sowie Futterverluste minimiert werden können. Die vorliegende Untersuchung vergleicht das Fressverhalten und die Körperhaltung von acht Pferden beim Einsatz von drei unterschiedlichen Futterraufen mit der Bodenfütterung in Einzelboxenhaltung. Die Ergebnisse dieser Studie lassen den Schluss zu, dass der Einsatz von Raufutterraufen die Futteraufnahmezeiten verlängert und somit längere Beschäftigungszeiten für die Futteraufnahme gewährleistet werden. Außerdem konnte festgestellt werden, dass die Pferde das Raufutter bei einer der drei untersuchten Raufen überwiegend mit natürlicher Kopf- Hals-Haltung aufnahmen. [Regarding the species horse, an appropriate supply of roughage should take into account the need to chew as well as the need for occupation. In this context, and due to the current cost pressure for hay, the interest in roughage racks increases. It is assumed that roughage racks could help to extend the feeding time and reduce food losses. The present study places the emphasis on the observation of the feeding behaviour of eight horses in single horse boxes. Three different roughage racks are compared to traditional feeding on the floor. On the basis of the results it may be concluded that the use of roughage racks extends the feeding time and thus ensures longer occupation. In one of the three roughage racks investigated the horses mainly eat in a natural posture of their head and neck.] |
|
Graf, P., König von Borstel, U., & Gauly, M. (2014). Practical considerations regarding the implementation of a temperament test into horse performance tests: Results of a large-scale test run. Journal of Veterinary Behavior: Clinical Applications and Research, 9(6), 329–340.
Abstract: Abstract Considering the ever-growing demand of various breeding organizations for an objective, inexpensive, reliable, and easily conducted assessment of the behavior of horses, the aim of our study was to implement a novel-object test and a startling test into any kind of breeding performance testing to assess horses' temperament. Additionally, the influence of testing areas (familiar or unfamiliar), riders, and horse factors such as levels of training, breed, and age were of interest. Furthermore, recommendations for the practical implementation concerning the parameters should be given. Therefore, 1,028 horses over a period of 3 years participated in a temperament test consisting of 5 different stimuli. The horses were either ridden (61.8 %) or led by hand (38.2 %) by an unfamiliar professional rider (N = 43) or a familiar rider (N = 20). Live behavioral observations were taken by a trained observer. Overall, horses' scores for reactivity in the present temperament test were distributed over the whole scale, with lower means and higher standard deviations (6.7 ± 2.2-7.6 ± 2.1) than corresponding scores from the conventional personality evaluation in performance tests (7.7 ± 0.8-8.2 ± 0.5; P < 0.01). High correlations (r = 0.3-0.9; P < 0.001) between the scores for reactivity and the other behavioral parameters (emotional expression, activity, time to calm down, rider's aids) show a large influence of these parameters in assessing the horses' temperament. Factors like breed type, sex, and age had significant influences (P < 0.001) on different scores of the temperament test. In most cases, the rider or handler had no influence on the different scores assessed during the temperament test. The training level and the testing modus never had a significant influence on different scores. Only the testing station or location had a small influence on the scores for the stimulus “bridge” in some horses. Based on the results, it could be concluded that an implementation of a temperament tests into performance testing is possible during various types of testing procedure. Especially the assessment of reactivity, emotional expression, interest in the stimulus and rider's aids during and after passing the stimulus, as well as the time to calm down are important parameters for analyzing the horses' personality.
Keywords: novel object test; temperament; personality; horse; performance traits; performance tests
|
|
Méary, D., Li, Z., Li, W., Guo, K., & Pascalis, O. (2014). Seeing two faces together: preference formation in humans and rhesus macaques. Animal Cognition, , 1–13.
Abstract: Humans, great apes and old world monkeys show selective attention to faces depending on conspecificity, familiarity, and social status supporting the view that primates share similar face processing mechanisms. Although many studies have been done on face scanning strategy in monkeys and humans, the mechanisms influencing viewing preference have received little attention. To determine how face categories influence viewing preference in humans and rhesus macaques (Macaca mulatta), we performed two eye-tracking experiments using a visual preference task whereby pairs of faces from different species were presented simultaneously. The results indicated that viewing time was significantly influenced by the pairing of the face categories. Humans showed a strong bias towards an own-race face in an Asian–Caucasian condition. Rhesus macaques directed more attention towards non-human primate faces when they were paired with human faces, regardless of the species. When rhesus faces were paired with faces from Barbary macaques (Macaca sylvanus) or chimpanzees (Pan troglodytes), the novel species’ faces attracted more attention. These results indicate that monkeys’ viewing preferences, as assessed by a visual preference task, are modulated by several factors, species and dominance being the most influential.
Keywords: Humans; Rhesus macaques; Preferences; Faces; Eye-tracking
|
|
Krueger, K., Farmer, K., & Heinze, J. (2014). The effects of age, rank and neophobia on social learning in horses. Anim. Cogn., 17(3), 645–655.
Abstract: Social learning is said to meet the demands of complex environments in which individuals compete over resources and co-operate to share resources. Horses (Equus caballus) were thought to lack social learning skills because they feed on homogenously distributed resources with few reasons for conflict. However, the horse’s social environment is complex, which raises the possibility that its capacity for social transfer of feeding behaviour has been underestimated. We conducted a social learning experiment using 30 socially kept horses of different ages. Five horses, one from each group, were chosen as demonstrators, and the remaining 25 horses were designated observers. Observers from each group were allowed to watch their group demonstrator opening a feeding apparatus. We found that young, low ranking, and more exploratory horses learned by observing older members of their own group, and the older the horse, the more slowly it appeared to learn. Social learning may be an adaptive specialisation to the social environment. Older animals may avoid the potential costs of acquiring complex and potentially disadvantageous feeding behaviours from younger group members. We argue that horses show social learning in the context of their social ecology, and that research procedures must take such contexts into account. Misconceptions about the horse’s sociality may have hampered earlier studies.
Keywords: Horse; Social learning; Sociality; Ecology; Social relationships
|
|
Krueger, K., Flauger, B., Farmer, K., & Hemelrijk, C. (2014). Movement initiation in groups of feral horses. Behav. Process., 103, 91–101.
Abstract: Abstract Herds of ungulates, flocks of birds, swarms of insects and schools of fish move in coordinated groups. Computer models show that only one or very few animals are needed to initiate and direct movement. To investigate initiation mechanisms further, we studied two ways in which movement can be initiated in feral horses: herding, and departure from the group. We examined traits affecting the likelihood of a horse initiating movement i.e. social rank, affiliative relationships, spatial position, and social network. We also investigated whether group members join a movement in dominance rank order. Our results show that whereas herding is exclusive to alpha males, any group member may initiate movement by departure. Social bonds, the number of animals interacted with, and the spatial position were not significantly associated with movement initiation. We did not find movement initiation by departure to be exclusive to any type of individual. Instead we find evidence for a limited form of distributed leadership, with higher ranking animals being followed more often.
Keywords: Horse; Equus ferus caballus; Distributed leadership; Herding; Departure; Rank
|
|
Kristjansson, T., Bjornsdottir, S., Sigurdsson, A., Andersson, L. S., Lindgren, G., Helyar, S. J., et al. (2014). The effect of the ‘Gait keeper’ mutation in the DMRT3 gene on gaiting ability in Icelandic horses. J. Anim. Breed. Genet., , n/a-n/a.
Abstract: A nonsense mutation in DMRT3 (‘Gait keeper’ mutation) has a predominant effect on gaiting ability in horses, being permissive for the ability to perform lateral gaits and having a favourable effect on speed capacity in trot. The DMRT3 mutant allele (A) has been found in high frequency in gaited breeds and breeds bred for harness racing, while other horse breeds were homozygous for the wild-type allele (C). The aim of this study was to evaluate further the effect of the DMRT3 nonsense mutation on the gait quality and speed capacity in the multigaited Icelandic horse and demonstrate how the frequencies of the A- and C- alleles have changed in the Icelandic horse population in recent decades. It was confirmed that homozygosity for the DMRT3 nonsense mutation relates to the ability to pace. It further had a favourable effect on scores in breeding field tests for the lateral gait tölt, demonstrated by better beat quality, speed capacity and suppleness. Horses with the CA genotype had on the other hand significantly higher scores for walk, trot, canter and gallop, and they performed better beat and suspension in trot and gallop. These results indicate that the AA genotype reinforces the coordination of ipsilateral legs, with the subsequent negative effect on the synchronized movement of diagonal legs compared with the CA genotype. The frequency of the A-allele has increased in recent decades with a corresponding decrease in the frequency of the C-allele. The estimated frequency of the A-allele in the Icelandic horse population in 2012 was 0.94. Selective breeding for lateral gaits in the Icelandic horse population has apparently altered the frequency of DMRT3 genotypes with a predicted loss of the C-allele in relatively few years. The results have practical implications for breeding and training of Icelandic horses and other gaited horse breeds.
Keywords: Gaiting ability; genotype effect; genotype probability
|
|
Nuñez, C. M. V., Adelman, J. S., Smith, J., Gesquiere, L. R., & Rubenstein, D. I. (2014). Linking social environment and stress physiology in feral mares (Equus caballus): Group transfers elevate fecal cortisol levels. General and Comparative Endocrinology, 196, 26–33.
Abstract: Abstract Feral horses (Equus caballus) have a complex social structure, the stability of which is important to their overall health. Behavioral and demographic research has shown that decreases in group (or band) stability reduce female fitness, but the potential effects on the physiological stress response have not been demonstrated. To fully understand how band stability affects group-member fitness, we need to understand not only behavioral and demographic, but also physiological consequences of decreases to that stability. We studied group changes in feral mares (an activity that induces instability, including both male and female aggression) on Shackleford Banks, NC. We found that mares in the midst of changing groups exhibit increased fecal cortisol levels. In addition, mares making more group transfers show higher levels of cortisol two weeks post-behavior. These results offer insights into how social instability is integrated into an animal’s physiological phenotype. In addition, our results have important implications for feral horse management. On Shackleford Banks, mares contracepted with porcine zona pellucida (PZP) make approximately 10 times as many group changes as do untreated mares. Such animals may therefore be at higher risk of chronic stress. These results support the growing consensus that links between behavior and physiological stress must be taken into account when managing for healthy, functional populations.
Keywords: Equus caballus; Fecal cortisol; Feral mare; Group transfer; Stress; Social instability
|
|
Benz, B., Köhnke, J., & Kappelmann, K. (2014). Bewertung einer Faltschieberanlage in einem Reitstall mit Paddockboxen[Assessment of a v-form scraper in a horse barn with paddock boxes]. Landtechnik, Agricultural Engineering,, 68(4), 242–247.
Abstract: In der vorliegenden Untersuchung werden in einem Praxisbetrieb die Verfahrenskosten eines
Faltschiebers erhoben. Aufgrund des reduzierten Arbeitszeitaufwandes ergibt sich durch den Einsatz des Faltschiebers eine jährliche Kostenersparnis in Höhe von 78 € je Pferd. Durch die Mechanisierung der Entmistung kann fast 30 % der Arbeitszeit in der Pensionspferdehaltung eingespart werden. Beim Einsatz einer Entmistungstechnik spielt jedoch nicht nur die Ökonomie, sondern darüber hinaus auch das Pferdeverhalten eine Rolle. Im selben Praxisbetrieb wird nach Installation der Faltschieberanlage das Pferdeverhalten beim Erstkontakt mit dem Schieber beobachtet. Dabei zeigt sich, dass die Pferde den direkten Kontakt mit der Entmistungstechnik und somit kritische Situationen vermeiden. [In the survey at hand, the procedural costs for a v-form scraper are gathered. In the process, it is found that due to the reduced working time requirement the use of a v-form scraper saves € 78/horse/year. The mechanization of manure removal can reduce working time in horse keeping by almost 30 percent. However, using manure removal systems, the profitability is not the only crucial criteria. The behaviour of the horses plays an essential role, too. Moreover the horses’ behaviour when first encountering the manure scraper is observed. The study reveals that the horses avoid contact with the scraper and thereby also shirk critical situations.] |
|
Kruska, D. C. T. (2014). Comparative quantitative investigations on brains of wild cavies (Cavia aperea) and guinea pigs (Cavia aperea f. porcellus). A contribution to size changes of CNS structures due to domestication. Mamm Biol, 79(4), 230–239.
Abstract: Intraspecific allometric calculations of the brain to body size relation revealed distinct differences between 127 (67; 60) ancestral wild cavies and 82 (37; 45) guinea pigs, their domesticated relatives. The dependency of both measures from one another remained the same in both animal groups but the brains of guinea pigs were by 14.22% smaller at any net body weight. Consistent with results in other species the domestication of Cavia aperea is also characterized by a decrease of brain size. Fresh tissue sizes of the five brain parts medulla oblongata, cerebellum, mesencephalon, diencephalon and telencephalon were determined for 6 cavies and 6 guinea pigs by the serial section method. Additionally the sizes of 16 endbrain structures and those of the optic tract, the lateral geniculate body and the cochlear nucleus were measured. Different decrease values resulted for all these structures concomitant with domestication as was calculated from the amount of total brain size decrease and average relative structure values in the wild as well as the domesticated brain. The size decrease of the entire telencephalon (-13.7%) was within the range of the mean overall reduction as similarly was the case for the total neocortex (-10.7%) whereas the total allocortex (-20.9%) clearly was more strongly affected. The size decrease of the olfactory bulb (-41.9%) was extreme and clearly higher than found for the secondary olfactory structures (around -11%). The primary nuclei of other sensory systems (vision, audition) were decreased to less extent (lateral geniculate: -18.1%; cochlear nucleus: -12.6%). Mass decreases of pure white matter parts were nearly twice as high in contrast to associated grey matter parts (neocortex white versus grey matter; tractus opticus versus lateral geniculate body). The relatively great decrease values found for the limbic structures hippocampus (-26.9%) and schizocortex (-25.9%) are especially notable since they are in good conformity with domestication effects in other mammalian species. The findings of this study are discussed with regard to results of similar investigations on wild and domesticated gerbils (Meriones unguiculatus), the encephalization of the wild form, the special and species-specific mode and duration of domestication and in connection with certain behavioral changes as resulted from comparative investigations in ethology, socio-biology, endocrinology and general physiology.
|