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Shultz, S. (2012). Are equid brains social? Exploring the evolution of equid social structure and social intelligence. In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: The living equids display a variety of different forms of social organisation; plains (Equus quagga) and mountain zebra (Equus zebra) associate in small, closed harems, whereas the asses and Grevy’s zebra (Equus grevyi) are found in looser, more ephemeral associations. Feral domestic horses appear to be somewhat intermediate: although stallions generally maintain harems, there is some movement of individuals between groups. This talk will use several statistical approached to explore evolutionary explanations for these differences. Firstly, we will explore the relationship between brain architecture and social organisation both among the equids and across all Perissodactyls. Equids have larger relative neocortices than other Perissodactyls; within the equids, species typically found in more stable groups have larger neocortices than equids in more unstable ephemeral groups. The strong relationship between group stability and brain size and architecture mirrors that found in other mammals, including primates. Thus, living in stable social groups consistently appears to impose cognitive demands across species. In order to understand the historical trajectory resulting in the relatively large, social brains found in some species, we then reconstruct the evolutionary pathway of social living in the equids. Finally, we discuss how we can use network theory to measure social structure and how these differences may impose different cognitive demands on individuals.
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Hori, Y., Takimoto, A., & Fujita, K. (2012). Are there breed difference in referential behavior in horses (Equus caballus)? In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: Domesticated animals are characterized by variability of breeds. There is a great diversity in body size and/or coat color between different breeds. However, there are few scientific researches about difference in cognition and behavior between breeds. Comparison of behavior between breeds may be useful for the study of genetics behind the diversity of cognition and behavior. In the present study, we investigated behavioral differences between horse breeds. We tested two different breeds which have different histories, thoroughbreds and creoles. Thoroughbreds are racing horses which have been exposed to strict selection toward racing performance for about 300 years. Creoles are descendents of horses which were brought to South America by Spanish people in 15th century and used by native cowboys for riding. We compared the behavior in a difficult situation by using an “unsolvable task”. The experimenter put a food reward into a transparent box and closed it firmly so that horses could not take the reward. We compared the referential behavior (gazing behavior toward the experimenter) between thoroughbreds and creoles. We analyzed referential behavior by using generalized linear models (GLM) and model selection by Akaike’s information criterion (AIC). There were no effect of breed in the frequency and the duration of the referential behavior. But the latency before looking at the experimenter tended to be shorter in thoroughbreds than in creoles. This result suggests that there may be breed differences in horses’ social cognition and behavior. However, the effect of sex was also seen. Furthermore, we could not exclude the environmental effect (e. g. feeding environments, trainings) in this study. So we cannot explain the variation in referential behavior by breed effect only. We need to replicate the result by controlling environmental effects.
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Lojek, J., Lojek, A., & Zielinska, A. (2012). Certain factors influencing the condition of free-ranging Konik Polski horses (Equus caballus) in the Bierza National Park. In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: The objective of the study was to analyze certain factors influencing the condition of free-ranging Konik Polski horses in a fenced area measuring 200 ha located in the Biebrza National Park (Biebrza NP). The Body Condition Scoring system (BCS) was used not only as means of assessment of health and fitness of the horses but also for evaluation of the quality and productivity of the grazing area selected for horses, as well as stocking rate. Body Condition Scoring was determine with a 9-point scale by averaging the scores that were assigned to each of the six body areas that are most responsive to changes of body fat (Hennecke, 1983). The condition of horses was assessed 7 times from February 2009 to December 2011 on a total of 59 horses (3 stallions (n= 12 observations), 21 females 3–8 year olds (n=81) and 35 youngsters (up to 2 year olds) (n=88). The number (from 1 to 3) and composition of family bands varied throughout the period of investigation. The horse population in the Biebrza NP consist of horses from 3 different breeding centers. The analysis of variance (GLM) was used to investigate the effects of the fixed factors – weather conditions, family band, breeder of the horses, age and sex, on the mean of BCS points of horses (SPSS, version 19.0). The most important factor influencing the condition of free-ranging Konik Polski horses in the Biebrza NP were weather conditions, what is shown by the data concerning temperature from 3-month period preceding condition scoring (P < 0.01). This factor influenced not only animals, but also vegetation characteristics. The highest BCS means of horses (5.09) were achieved when average temperature during the 3-month period preceding condition scoring amounted between +1 to +8°C, and was better than obtained when average temperature amounted +18°C (4.80). The last temperature seems too high for horses and can be connected also with other factors, like high incidence of insects which could deteriorate grazing activity of animals. The lowest BCS means (4.56) were obtained when mean temperature was below 0°C. Other factors had no significant effect on the BCS means. As concern to breeder, the highest BCS means achieved mares from Popielno (5.08) – the oldest Polish free-ranging population of Konik Polski horses, which confirms that horses from this breeding center are justly considered to be the toughest and well adapting to difficult environmental conditions. The horses from the Biebrza NP achieved also high BCS means (4.79) which prove that they were well suited to the specific conditions of this habitat, which is overgrown mostly with forest – 73,7%, and willow and birch shrubs – 13,3% of area. The grazing area measures about 40 hectares and consists of wetlands dominated by sedges (Carex sp.). The horses moved from the Seven Island Reservation to Biebrza NP achieved the poorest results as far as adaptation to the conditions of the new habitat, and reached the lowest BCS means (4.57). The youngest horses (up to 2 year olds), 3-5 year olds, and 6-8 year olds had similar BCS means (respectively 4.94, 4.83, 4.68) which indicates good acclimatization of horses from different age categories to the grazing resources in the Biebrza NP. The highest means achieved by youngest horses indicate important trait of Konik Polski horses – mare`s careful care of offspring. The BCS means of horses from different family groups show the highest value of horses from family group of the most experienced stallion – Mrok (4.97). In every BCS scoring, stallions achieved the highest means, which was the reason to exclude their results from analysis. The results of this study suggest that the Body Condition Scoring of horses in the Biebrza National Park depends primarily on the acclimatization of horses to harsh environmental conditions and less importantly to belonging to a specific breeder, family band, age or sex.
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Ben-Shlomo, G., Plummer, C., Barrie, K., & Brooks, D. (2012). Characterization of the normal dark adaptation curve of the horse. Veterinary Ophthalmology, 15(1), 42–45.
Abstract: Objective The goal of this work is to study the dark adaptation curve of the normal horse electroretinogram (ERG). Procedures The electroretinographic responses were recorded from six healthy female ponies using a contact lens electrode and a mini-Ganzfeld electroretinographic unit. The horses were sedated intravenously with detomidine, an auriculopalpebral nerve block was then performed, and the pupil was fully dilated. The ERG was recorded in response to a low intensity light stimulus (30 mcd.s/m2) that was given at times (T) T = 5, 10, 15, 20, 25, 30, 40, 50, and 60 min of dark adaptation. Off-line analysis of the ERG was then performed. Results Mean b-wave amplitude of the full-field ERG increased continuously from 5 to 25 min of dark adaptation. The b-wave amplitude peaked at T = 25, however, there was no statistical significance between T = 20 and T = 25. The b-wave amplitude then remained elevated with no significant changes until the end of the study at T = 60 (P > 0.49). The b-wave implicit time increased continuously between T = 5 and T = 20, then gradually decreased until T = 60. No distinct a-wave was observed during the testing time. Conclusions Evaluation of horse rod function or combined rod/cone function by means of full-field ERG should be performed after a minimum 20 min of dark adaptation.
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Zeitler-Feicht, M. H., & Streit, S. (2012). Checkpunkte für eine tiergerechte Fütterung von Pferden an Abrufautomaten. In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: In der Offenstallhaltung von Pferden wird für die individuelle Fütterung der Fressstand, der eine art-typische synchrone Nahrungsaufnahme erlaubt, empfohlen (BMELV 2009). Seit einigen Jahren kommen jedoch vermehrt Abrufstationen für Kraft- und Raufutter zum Einsatz. Diese ermöglichen nur ein asynchrones Fressen, was das Risiko für Auseinandersetzungen im Fressbereich erhöht.
In einer repräsentativen Studie an insgesamt 567 individuell unterschiedenen Pferden in 32 Offen-laufställen mit Abrufstationen und 10 Betrieben mit Fressständen wurden die Aufenthaltsdauer und Besuchshäufigkeit sowie das Droh- und Meideverhalten der Pferde im Fütterungsbereich und die Häu-figkeit von Blockaden erfasst, des Weiteren Herzfrequenz und Integumentverletzungen. Fazit war, dass es an den Abrufstationen doppelt so oft zu Auseinandersetzungen kam als an den Fressständen. Als Ursache hierfür konnte die starke Frequentierung der Automaten eruiert werden. Umso wichtiger ist somit die tiergerechte Ausführung der Abrufautomaten. In der Studie konnte nachgewiesen werden, dass Durchlaufstationen pferdegerechter sind als Rücklaufstationen. Als nicht tiergerecht wurden Stationen mit Strom führender Austreibehilfe.eingestuft. Die für das fressende Pferd als verhaltens-gerecht empfohlene Variante (Fressstand mit Eingangssperre und ohne Austreibehilfe) führte zu einer Erhöhung der Besuchshäufigkeit und Aufenthaltsdauer und somit auch zu einer erhöhten Anzahl an Drohgesten je Tier und Tag. Die Herzfrequenz lag im Wartebereich bei den meisten Pferden im physio-logischen Bereich (45,1 ± 12,42 Schläge/min), erhöhte sich jedoch in der Abrufstation um ca. 20 Schlä-ge/min. Einige Tiere zeigten möglicherweise stressbedingt auffallend hohe Herzfrequenzwerte ( 100 Schläge/min). Integumentverletzungen im Zusammenhang mit dem Fütterungssystem traten nicht auf. Das Flächengebot und die Konzeption der Offenstallanlage sowie das Management erwiesen sich als maßgebliche Einflussfaktoren auf alle überprüften Kriterien zur Tiergerechtheit.
Um die Anzahl an Auseinandersetzungen im Fütterungsbereich von Abrufstationen zu mindern wird eine Reduzierung der Fütterungshäufigkeit von üblicherweise bis zu 24 Mahlzeiten auf nur 10 Mahlzeiten empfohlen, gemäß dem natürlichen Fressrhythmus von Pferden. Unabhängig vom Fütterungssystem traten die wenigsten Auseinandersetzungen auf, wenn die Pferde täglich etwa 1,5 kg Heu pro 100 kg Körpermasse erhielten bei zusätzlicher ad Libitum Fütterung von Stroh.
Nach bisherigen Erkenntnissen ergeben sich nachfolgende Checkpoints für Abrufautomaten:
Checkpunkte für Abrufstationen
 Schutz des Pferdes durch Trennwände über die gesamte Körperlänge
 Trennwände mit Sichtkontakt zu den anderen Pferden
 Durchlaufstationen mit separatem Ein- und Ausgang
 Eingangssperre für eine stressfreie Futteraufnahme
 Ausgang mit Pendeltüre und Rücklaufsperre
 Ausgang in einen anderen Funktionsbereich
 Ausreichend Ausweichmöglichkeiten für rangniedere Tiere
 Räumliche Trennung von Kraftfutter- und Heuautomaten
 Maximal je 10 Kraft- und Grobfutterrationen je Tier und Tag
 ≥ 1,5 kg Heu bzw. Heulage pro 100 kg Körpermasse je Pferd und Tag
 Stroh zur freien Verfügung (Möglichkeit zum synchronen Fressen)
 Individuelles Anlernen der Pferde am Automaten erforderlich
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Chittka, L., & Dyer, A. (2012). Cognition: Your face looks familiar. Nature, 481(7380), 154–155.
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Gabor, V., & Gerken, M. (2012). Cognitive testing in Shetland ponies (Equus caballus) using a computer based learning device. In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: Complex housing environments such as group housing with automatic feeding or the close contact to humans in sports make high demands on the learning ability of the horse. These learning processes include not only habituation, sensitization and simpler forms of operant conditioning, but also stimulus generalization and possibly some type of concept learning. Studies concerning cognitive abilities in the horse increased in the last decades, but for optimizing housing conditions and horse training, deeper insight into the learning behaviour of this species is necessary. In the present study we used the advantages of a computer based learning device to train 7 Shetland ponies to solve a matching to sample task. With this more complex type of a discrimination task, animals are trained to recognize two out of three presented stimuli as identical. In a first step animals learned to operate the learning device and in further learning steps to recognize and assign geometric symbols (dot, cross, square, and triangle) presented on a LCD screen that were ‘equal’. Four of the 7 ponies could solve the given task by performing over 80% correct responses in two consecutive sessions (p < 0.001). In the subsequent transfer test with new symbols, we found that the ponies were able to transfer the learned rule. In further experiments it should be clarified whether the good learning performance of the ponies in the present study is indeed based on their capability to form an abstract concept of sameness. The present results indicate that ponies possibly posses higher cognitive abilities than so far known.
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Ahmadinejad, M., Tavakoli, S. (2012). Common injuries in athletic horses in Tehran‘s riding clubs. In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press).
Abstract: Various forms of intensive sport activities places stresses on the musculoskeletal system of the horse while involve in any forms of the activity (race &/or training). The musculoskeletal system of the horse has an inherent ability to adapt to the demands of high speed exercise, though if a threshold in adaptive capacity is exceeded, then some forms of damages to the structures of the musculoskeletal system may result. In case, if the insult (race &/or training) continued, it may worsen the repair and adaptation process and put the horse at risk of more serious musculoskeletal injury.
The result of this research describe the finding of the study performed in different breeds of horses involved in various types of activity in Tehran’s riding clubs, concentrating on the types of injuries observed in those horses. The study was then focused on the types of injuries observed in various activities (events) horses involved in.
Totally 400 horses took part in various activities during race season (March – September) in Tehran’s riding clubs, out of which 26 horses injured, in most of which musculoskeletal system of the fore limbs were involved.
From the sexual aspect of the study the percentages of the stallions were more (54%) when compared to the mares (46%). In this study the relation between the sex, breed, age and the weight of the horses with anatomical site of the injury, outcome of the injury, climate and the type of the event (jumping, polo etc.) were studied and compare with each other.
Bibliography:
Hill AE, Stover SM, Gardner IA, Kane AJ, Whitcomb MB, Emerson AG, 2001. Risk factors for and outcomes non catastrophic suspensory apparatus injury in Thoroughbred race horse. J.A.V.M.A. 218, 1136-44
Johnson BJ 1993. A look at race horse breakdowns. J.Eq.Vet.Scie. 13, 129-32
Morse SJ. 1999. A longitudinal study of racing thoroughbreds; performance during the first year of racing. Aust.Vet.J. 77, 105-12
Peloso JG, Mundy GD, Cohen ND. 1994. Prevalence of, and factors associated with, musculoskeletal racing injuries of thoroughbreds. J.A.V.M.A. 204, 620-6
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Smaers, J. B., Dechmann, D. K. N., Goswami, A., Soligo, C., & Safi, K. (2012). Comparative analyses of evolutionary rates reveal different pathways to encephalization in bats, carnivorans, and primates. Proc Natl Acad Sci U S A, 109.
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Belock, B., Kaiser, L. J., Lavagnino, M., & Clayton, H. M. (2012). Comparison of pressure distribution under a conventional saddle and a treeless saddle at sitting trot. The Veterinary Journal, 193(1), 87–91.
Abstract: It can be a challenge to find a conventional saddle that is a good fit for both horse and rider. An increasing number of riders are purchasing treeless saddles because they are thought to fit a wider range of equine back shapes, but there is only limited research to support this theory. The objective of this study was to compare the total force and pressure distribution patterns on the horse’s back with conventional and treeless saddles. The experimental hypotheses were that the conventional saddle would distribute the force over a larger area with lower mean and maximal pressures than the treeless saddle. Eight horses were ridden by a single rider at sitting trot with conventional and treeless saddles. An electronic pressure mat measured total force, area of saddle contact, maximal pressure and area with mean pressure >11 kPa for 10 strides with each saddle. Univariate ANOVA (P < 0.05) was used to detect differences between saddles. Compared with the treeless saddle, the conventional saddle distributed the rider’s bodyweight over a larger area, had lower mean and maximal pressures and fewer sensors recording mean pressure >11 kPa. These findings suggested that the saddle tree was effective in distributing the weight of the saddle and rider over a larger area and in avoiding localized areas of force concentration.
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