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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.
Keywords: adaptation; curve; dark; electroretinography; equine; scotopic
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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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Van Schaik, C. P., Isler, K., & Burkart, J. M. (2012). Explaining brain size variation: from social to cultural brain. Trends Ecol Evol, 16.
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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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Munsters, C. C. B. M., Visser, K. E. K., van den Broek, J., & Sloet van Oldruitenborgh-Oosterbaan, M. M. (2012). The influence of challenging objects and horse-rider matching on heart rate, heart rate variability and behavioural score in riding horses. The Veterinary Journal, 192(1), 75–80.
Abstract: A good horse-rider ‘match’ is important in the context of equine welfare. To quantify the influence of repetition and horse-rider matching on the stress of horses encountering challenging objects, 16 Warmblood horses were ridden in a test-setting on three occasions. On each occasion the horse was ridden by a different rider and was challenged by three objects (A–C). Heart rate (HR), heart rate variability (HRV) of horse and rider, and behaviour score (BS) of the horse were obtained for each object and as a total for each test. The horse-rider interaction was evaluated with each combination and assessed as ‘matching’ or ‘mismatching’, and the horses were categorised as ‘compliant’, ‘partly-compliant’ or ‘non-compliant’. Horses exhibited a decreased HR (P = 0.015) and a decreased BS (P = 0.004) within and across different tests. ‘Matching’ horse-rider combinations exhibited less stress as indicated by reduced HR (‘match’ 69 ± 10 vs. ‘mismatch’ 72 ± 9, P = 0.001) and BS (‘match’ 1.9 ± 1.1 vs. ‘mismatch’ 3.8 ± 1.4, P = 0.017) of the horse. ‘Compliant’ (68 ± 8, P < 0.001) and ‘partly-compliant’ (71 ± 9, P = 0.002) horses had significantly lower HR than ‘non-compliant’ (75 ± 9) animals. The findings of the study indicate that HR and BS measurements support a subjective ‘match’ diagnosis and HR measurement may be a valuable tool in assessing horse compliance.
Keywords: Horse-rider interaction; Horse compliance; Welfare; Heart rate; Behaviour score
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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.
Keywords: Horse; Rider; Equitation; Tack; Electronic pressure mat
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Casella, S., Fazio, F., Giannetto, C., Giudice, E., & Piccione, G. (2012). Influence of transportation on serum concentrations of acute phase proteins in horse. Research in Veterinary Science, 93(2), 914–917.
Abstract: The modifications of Haptoglobin (Hp), Serum Amyloid A (SAA), Fibrinogen (Fbg) and White Blood Cells (WBCs) were evaluated in 15 Saddle Italian horses. Ten horses were transported covering a distance of about 320 km within 4 h with an average speed of 80 km/h (experimental group) and five horses were not subject to transportation (control group). Blood was collected via jugular venipuncture before the transportation (T0), immediately after the transportation (T1), 12 (T12), 24 (T24) and 48 (T48) hours after the transportation in experimental group and at the same time point in control group. For each parameter statistical analysis of different groups and sampling time was performed using a two-way analysis of covariance, with the data before the transportation (T0) as the covariate, by the GLM procedure of SAS. For all parameters the interaction (Group × Time) was tested and it was resulted no significant. The application of statistical analysis showed significant differences between the control group and horses subjected to transportation (P < 0.01), and the influence of sampling time (P < 0.05) on Hp, SAA and WBCs. These modifications appeared to be innovative showing that equine Hp, generally considered as moderate acute phase protein, increases more rapidly than the SAA after transportation-induced stress.
Keywords: Acute phase proteins; Horse; Transportation stress; Welfare; White Blood Cells
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Ayala, I., Martos, N. F., Silvan, G., Gutierrez-Panizo, C., Clavel, J. G., & Illera, J. C. (2012). Cortisol, adrenocorticotropic hormone, serotonin, adrenaline and noradrenaline serum concentrations in relation to disease and stress in the horse. Research in Veterinary Science, 93(1), 103–107.
Abstract: No detailed comparative data are available on the hormonal parameters of horses suffering from a number of diseases. The aim of our study was to measure concentrations of cortisol, adrenocorticotropic hormone (ACTH), serotonin, adrenaline and noradrenaline in horses with various diseases and following surgery, to assess the response of the HPA axis and adrenal medulla. Blood samples were obtained from six groups of horses comprising a total of 119 animals as follows: laminitis, acute abdominal syndrome (AAS), castration surgery, acute diseases, chronic diseases and healthy controls. Serum hormonal concentrations were determined for each group for comparison. Statistically significant differences between all groups and controls were found for cortisol, ACTH (except for castration), serotonin and adrenaline concentrations but only in horses with laminitis and AAS for noradrenaline. No statistically significant differences were found between males and females. The largest changes in the pituitary–adrenal axis activity occurred mainly in acute diseases, laminitis and in the AAS group.
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Proops, L., & McComb, K. (2012). Cross-modal individual recognition in domestic horses (Equus caballus) extends to familiar humans. Proceedings of the Royal Society B: Biological Sciences, 279(1741), 3131–3138.
Abstract: It has recently been shown that some non-human animals can cross-modally recognize members of their own taxon. What is unclear is just how plastic this recognition system can be. In this study, we investigate whether an animal, the domestic horse, is capable of spontaneous cross-modal recognition of individuals from a morphologically very different species. We also provide the first insights into how cross-modal identity information is processed by examining whether there are hemispheric biases in this important social skill. In our preferential looking paradigm, subjects were presented with two people and playbacks of their voices to determine whether they were able to match the voice with the person. When presented with familiar handlers subjects could match the specific familiar person with the correct familiar voice. Horses were significantly better at performing the matching task when the congruent person was standing on their right, indicating marked hemispheric specialization (left hemisphere bias) in this ability. These results are the first to demonstrate that cross-modal recognition in animals can extend to individuals from phylogenetically very distant species. They also indicate that processes governed by the left hemisphere are central to the cross-modal matching of visual and auditory information from familiar individuals in a naturalistic setting.
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Schneider, A. - C., Melis, A. P., & Tomasello, M. (2012). How chimpanzees solve collective action problems. Proceedings of the Royal Society B: Biological Sciences, .
Abstract: We presented small groups of chimpanzees with two collective action situations, in which action was necessary for reward but there was a disincentive for individuals to act owing to the possibility of free-riding on the efforts of others. We found that in simpler scenarios (experiment 1) in which group size was small, there was a positive relationship between rank and action with more dominant individuals volunteering to act more often, particularly when the reward was less dispersed. Social tolerance also seemed to mediate action whereby higher tolerance levels within a group resulted in individuals of lower ranks sometimes acting and appropriating more of the reward. In more complex scenarios, when group size was larger and cooperation was necessary (experiment 2), overcoming the problem was more challenging. There was highly significant variability in the action rates of different individuals as well as between dyads, suggesting success was more greatly influenced by the individual personalities and personal relationships present in the group.
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