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Gaunitz, C., Fages, A., Hanghøj, K., Albrechtsen, A., Khan, N., Schubert, M., et al. (2018). Ancient genomes revisit the ancestry of domestic and Przewalski's horses. Science, 360(6384), 111–114.
Abstract: The Eneolithic Botai culture of the Central Asian steppes provides the earliest archaeological evidence for horse husbandry, ~5,500 ya, but the exact nature of early horse domestication remains controversial. We generated 42 ancient horse genomes, including 20 from Botai. Compared to 46 published ancient and modern horse genomes, our data indicate that Przewalski's horses are the feral descendants of horses herded at Botai and not truly wild horses. All domestic horses dated from ~4,000 ya to present only show ~2.7% of Botai-related ancestry. This indicates that a massive genomic turnover underpins the expansion of the horse stock that gave rise to modern domesticates, which coincides with large-scale human population expansions during the Early Bronze Age.
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Gehlen, H., Große, V., & Doher, M. (2012). Möglichkeiten und Grenzen des Herdenschutzes für Pferde in Zusammenhang mit der wachsenden Wolfspopulation in Deutschland Literaturrecherche und Befragung von Pferdehaltern zur Gefährdungsbeurteilung [Options and limitations of protecting horse husbandries in times of growing wolf populations in Germany Review of the literature and horse owner questionnaire on risk assessment]. Tierarztl Prax Ausg G, 49(05), 301–309.
Abstract: Zusammenfassung
Gegenstand und Ziel Seit 2000 siedelt sich der Wolf in Deutschland wieder an. Mit steigenden Wolfszahlen nehmen die durch Wölfe verursachten Nutztierschäden zu, wobei auch Pferde betroffen sind. Ziel der Studie war es, einen Überblick zu dieser Problematik sowie Lösungsansätze zu geben. Material und Methoden Anhand einer Literaturrecherche wurden Daten zur Wolfspopulation in Deutschland, wolfsbedingten Schäden sowie Möglichkeiten und Grenzen des Herdenschutzes beim Pferd eruiert. Eine Online-Befragung von Pferdehaltern/-besitzern diente dazu, die tatsächliche und/oder gefühlte Bedrohung durch Wölfe und die daraus resultierenden Auswirkungen auf die Pferdehaltung zu ermitteln. Ergebnisse Die Literaturrecherche zeigte ein kontinuierliches Anwachsen der Wolfspopulation in den letzten Jahren und insbesondere seit 2016 einen deutlichen Anstieg wolfsverursachter Nutztierschäden, wobei Pferde selten betroffen waren. Bei der Online-Befragung stammte die Hälfte der 574 ausgewerteten Fragebögen aus Brandenburg und Niedersachsen. Den größten Einfluss auf die Gefährdungsbeurteilung eigener Pferde durch die wachsende Wolfspopulation hatte das Wissen der Pferdehalter über Wolfsangriffe im eigenen Landkreis, wobei insbesondere die Aspekte einer Haltung von Jungpferden und Weidegang für die Pferde eine Rolle spielten. 64 % der Befragten gaben an, ihre Pferdehaltung trotz der zunehmenden Wolfspopulation nicht geändert zu haben. Nur 8 von 576 Pferdehaltern gaben amtlich bestätigte Wolfsübergriffe an und 30 hatten einen vermuteten Wolfsschaden amtlichen Stellen nicht gemeldet. Mehr als die Hälfte der Befragten, die Kontakt zu einem Wolfsberater hatten, bezeichneten die Zusammenarbeit als nicht bis wenig zielführend. Schlussfolgerung und klinische Relevanz Die Zahl amtlich bestätigter Wolfsangriffe auf Pferde ist gering. Durch einen grundsätzlich durchgeführten Gentest bei entsprechendem Verdacht ließen sich diese Zahlen objektivieren. Trotz des Bewusstseins einer zunehmenden Gefährdung von Pferden durch Wölfe unternehmen Pferdehalter überwiegend keine prophylaktischen Schutzmaßnahmen. Die Kommunikation zwischen den für das Wolfsmonitoring zuständigen Behörden und den Pferdehaltern erscheint verbesserungswürdig. Abstract Objective Since 2000 the wolf population is reestablishing itself in Germany. In consequence to increasing numbers, livestock damage caused by wolves is on the rise, with horses likewise being affected. The aim of the study was to provide an overview of this challenge and its possible solutions. Material and methods Based on a literature research, data on the wolf population in Germany, wolf-related damage as well as possibilities and limitations of herd protection for horses were evaluated. An online survey addressed to horse owners/keepers served to determine the actual and/or perceived threat posed by wolves and the resulting effects on horse husbandry. Results The literature search showed a continuous increase of the wolf population in recent years as well as a significant increase of wolf-caused livestock damage in general especially since 2016; although horses were rarely affected. Half of the 574 evaluated questionnaires were from Brandenburg and Lower Saxony. The greatest influence on the individual risk assessment concerning their own horses by the growing wolf population was the horse owners� knowledge of wolf attacks in their own county. Especially the aspects of keeping young horses as well as pasture keeping played a significant role. 64 % of respondents indicated that they had not changed their horse management practices despite the increasing wolf population. Only 8 of 576 horse owners had reported officially confirmed wolf attacks and 30 respondents had not reported a suspected wolf damage to official agencies. More than half of the respondents who had contact with a wolf advisor described the cooperation as either not or only slightly purposeful. Conclusion and clinical relevance The number of officially confirmed wolf attacks on horses is low. These numbers could be objectified by a routinely performed genetic test in case of corresponding suspicion. Despite the awareness of an increasing danger of horses by wolves, horse owners mostly do not undertake prophylactic protection measures. The communication between responsible authorities for wolf monitoring and horse owners seems to be in need of improvement. |
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Gentner, T. Q., Fenn, K. M., Margoliash, D., & Nusbaum, H. C. (2006). Recursive syntactic pattern learning by songbirds. Nature, 440(7088), 1204–1207.
Abstract: Humans regularly produce new utterances that are understood by other members of the same language community. Linguistic theories account for this ability through the use of syntactic rules (or generative grammars) that describe the acceptable structure of utterances. The recursive, hierarchical embedding of language units (for example, words or phrases within shorter sentences) that is part of the ability to construct new utterances minimally requires a 'context-free' grammar that is more complex than the 'finite-state' grammars thought sufficient to specify the structure of all non-human communication signals. Recent hypotheses make the central claim that the capacity for syntactic recursion forms the computational core of a uniquely human language faculty. Here we show that European starlings (Sturnus vulgaris) accurately recognize acoustic patterns defined by a recursive, self-embedding, context-free grammar. They are also able to classify new patterns defined by the grammar and reliably exclude agrammatical patterns. Thus, the capacity to classify sequences from recursive, centre-embedded grammars is not uniquely human. This finding opens a new range of complex syntactic processing mechanisms to physiological investigation.
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George, I., Cousillas, H., Richard, J. - P., & Hausberger, M. (2002). Song perception in the European starling: hemispheric specialisation and individual variations. Compt. Rend. Biol., 325(3), 197–204.
Abstract: Hemispheric specialisation for speech in humans has been well documented. The lateralisation for song production observed in songbirds is reminiscent of this hemispheric dominance. In order to investigate whether song perception is also lateralised, we made multiunit recordings of the neuronal activity in the field L of starlings during the presentation of species-specific and artificial non-specific sounds. We observed a systematic stronger activation in one hemisphere than in the other one during the playback of species-specific sounds, with inter-subject variability in the predominant hemisphere for song perception. Such an asymmetry was not observed for artificial non-specific sounds. Thus, our results suggest that, at least at the individual level, the two hemispheres of the starlings' brain perceive and process conspecific signals differently.
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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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Geutjens, C. A., Clayton, H. M., & Kaiser, L. J. (2008). Forces and pressures beneath the saddle during mounting from the ground and from a raised mounting platform. The Veterinary Journal, 175(3), 332–337.
Abstract: The objective was to use an electronic pressure mat to measure and compare forces and pressures of the saddle on a horse's back when riders mounted from the ground and with the aid of a mounting platform. Ten riders mounted a horse three times each from the ground and from a 35 cm high mounting platform in random order. Total force (summation of forces over all 256 sensors) was measured and compared at specific points on the force-time curve. Total force was usually highest as the rider's right leg was swinging upwards and was correlated with rider mass. When normalized to rider mass, total force and peak pressure were significantly higher when mounting from the ground than from a raised platform (P < 0.05). The area of highest pressure was on the right side of the withers in 97% of mounting efforts, confirming the importance of the withers in stabilizing the saddle during mounting.
Keywords: Electronic saddle mat; Total force; Peak pressure; Equestrian; Kinetics
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Gibson, K. T., Burbidge, H. M., & Anderson, B. H. (1997). Tendonitis of the branches of insertion of the superficial digital flexor tendon in horses. Aust Vet J, 75(4), 253–256.
Abstract: OBJECTIVE: To describe clinical findings, ultrasonographic features and outcome of injury to the branches of insertion of the superficial digital flexor (SDF) tendon in horses. DESIGN: Retrospective study of 14 cases. PROCEDURE: Fourteen Thoroughbred horses with tendonitis affecting the branches of insertion of the SDF tendon were examined for lameness, location and amount of swelling, and the presence of other musculoskeletal abnormalities. The flexor tendons were assessed by ultrasonographic examination, and recommendations were made for management of the cases. Outcome was assessed by re-examination of some horses, direct communication with the owner or trainer, and examination of race records. RESULTS: The lateral SDF branch was affected in 10 horses; the medial branch in three, and both branches in one horse. Two horses had concurrent injuries to the SDF tendon in the metacarpal region of the contralateral limb. Ultrasonographic findings included swelling of the affected SDF branch, peritendinous fluid accumulation, disruption of normal fibre alignment on sagittal scan, and variable loss of echogenicity. As healing occurred, there was return of normal echogenicity, but normal fibre alignment did not return completely and apparent adhesions formed between the affected SDF branch and adjacent structures. Seven of 10 horses which returned to their previous use were able to compete without further tendon injury. Recurrence of injury occurred in one case, and another two horses developed tendonitis in the metacarpal region. One horse was retired from racing but was able to compete at dressage without recurrence of injury. Two horses were retired for breeding without returning to training, and one horse was sold and lost to follow up but did not race. CONCLUSION: The prognosis is fair for return to previous use following injury to the branches of insertion of the SDF tendon in athletic horses.
Keywords: Animals; Carpus, Animal/pathology/physiopathology/ultrasonography; Horse Diseases/*diagnosis/pathology/ultrasonography; Horses; Prognosis; Retrospective Studies; Tendinopathy/diagnosis/pathology/*veterinary; Tendon Injuries/diagnosis/pathology/veterinary; Tendons/pathology/physiopathology/ultrasonography; Ultrasonography/methods/veterinary
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Giebel, H. D. (1958). Visuelles lernvermögen bei Einhufern. Zool. Jahrb. 67, , 229–231.
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Gilmanshin, R., Callender, R. H., & Dyer, R. B. (1998). The core of apomyoglobin E-form folds at the diffusion limit. Nat Struct Biol, 5(5), 363–365.
Abstract: The E-form of apomyoglobin has been characterized using infrared and fluorescence spectroscopies, revealing a compact core with native like contacts, most probably consisting of 15-20 residues of the A, G and H helices of apomyoglobin. Fast temperature-jump, time-resolved infrared measurements reveal that the core is formed within 96 micros at 46 degrees C, close to the diffusion limit for loop formation. Remarkably, the folding pathway of the E-form is such that the formation of a limited number of native-like contacts is not rate limiting, or that the contacts form on the same time scale expected for diffusion controlled loop formation.
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Golden, J. W., Kerley, M. S., & Kolath, W. H. (2007). The relationship of feeding behavior to feed efficiency in crossbred Angus steers fed traditional and no roughage diets. J. Anim Sci., , jas.2005–569-.
Abstract: Two studies were conducted to determine the relationship of feeding behavior to the phenotypic expression of feed efficiency. In Exp. 1, a feedlot diet containing roughage was fed (traditional). In Exp. 2, a no-roughage diet was fed. Residual feed intake (RFI), a measure of feed efficiency, was calculated for both studies. In Exp. 1, 6 feed efficient (low RFI) steers and 6 feed inefficient steers (high RFI) were selected from a contemporary group of 80 steers, and feeding behaviors were analyzed. In Exp. 2, 9 feed efficient and 8 feed inefficient steers were selected from a contemporary group of 40 steers. There were no differences (P > 0.13) in initial or final BW or ADG between efficient and inefficient groups in either Exp. 1 or 2. In Exp. 1 DMI and average eating bouts daily differed (P < 0.001) with efficient steers consuming less feed and eating fewer times per day. In Exp. 2, efficient steers consumed less (P < 0.001) feed, and average eating bouts daily tended (P = 0.07) to be fewer in efficient animals. Limited differences were noted in feeding behavior between groups, with inefficient steers from both studies having a more variable eating pattern throughout the day. The average daily eating rate did not differ (P > 0.20) between groups in either experiment. The average number of days comprising a feeding pattern for both feed efficiency groups in Exp. 1 and 2 was found to be 2 to 3 d and multiples of 2 to 3 d. In Exp. 1 the feed intake pattern of efficient and inefficient steers changed once they reached a BW of approximately 391 kg and 381 kg, respectively. This occurred near d 47 for the efficient steers and near d 32 for inefficient steers. In Exp. 2 the feed intake pattern of both efficient and inefficient steers changed once they reached a BW of approximately 399 kg, which occurred on d 31 for the efficient steers and on d 33 for the inefficient steers. From the measured variables there were no differences in growth and limited differences noted in feeding behavior between feed efficient and feed inefficient groups. The results of the trials suggest increased variability of feed intake throughout the day for feed inefficient animals.
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