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May, A. (2007). Evaluierung von Stressparametern beim Pferd im Zusammenhang mit dem Klinikaufenthalt [Evaluation of stress parameters in the hospitalized horse]. Ph.D. thesis, LMU München, München.
Abstract: Ein Klinikaufenthalt stellt für Pferde eine Stresssituation dar und viele Pferde erkranken
während eines Klinikaufenthalts an Stress-assoziierten Erkrankungen. Eine der häufigsten ist die so genannte Colitis X, eine oft tödlich verlaufende Durchfallerkrankung. Da es im Verlauf dieser Erkrankungen zu einem Verlust der Tiere kommen kann, hat ihre Vermeidung oberste Priorität. Ziel der vorliegenden Untersuchung war es, herauszufinden, inwieweit bei den Pferden der klinisch erkennbare Stress mit Veränderungen messbarer Blutparameter (Hämatokrit, Gesamteiweiß, Leukozyten, Glukose, Laktat, Kortisol) einhergeht und dabei einen Parameter zu finden, mit dem Stress beim Klinikpatienten Pferd verlässlich und möglichst einfach evaluiert werden kann. Zudem wurden in dieser Studie Freie Sauerstoffradikale („oxidativer Stress“) und IgA im Kot bestimmt, um diese Parameter auf ihre klinische Verwendbarkeit zu prüfen und zu untersuchen, inwieweit Stress mit dem lokalen Immunglobulingehalt interferiert. Einigen ausgewählten Pferden wurde zudem der Paramunitätsinducer Zylexis® der Firma Pfizer appliziert, um dessen Wirkung auf die untersuchten Parameter festzustellen. Es wurden 110 Patienten der Klinik für Pferde untersucht, die in dem Zeitraum der Studie zufällig hospitalisiert wurden. Die Pferde wurden in zwei Gruppen eingeteilt. Eine Gruppe wurde in der Klinik operiert, die zweite nur stationär behandelt. Des Weiteren wurde eine Kontrollgruppe in ihrem Heimatstall zum Vergleich miteinbezogen, die in den letzten sechs Wochen vor der Studie nicht transportiert oder anderweitig belastet worden war. Den Pferden wurde in definierten Abständen Blut und Kot entnommen, um den Einfluss von Transport, Operation und Klinikstress möglichst gut zu erfassen. Die Zeitpunkte waren direkt nach der Einlieferung, am Morgen vor der Narkose, nach der Aufstehphase und sowohl einen als auch vier Tage nach der Narkose. Pferden, die nicht operiert wurden und der Kontrollgruppe wurden insgesamt dreimal Blut und Kot (Tag 1, 3, Tag vor der Entlassung) entnommen. Für die Zylexis®-Studie wurden Vitrektomie-Patienten ausgewählt, da diese ein gutes Beispiel für eine kurze, wenig traumatische Operation darstellen. Diese Pferde wurden mit den anderen Pferden, die leichten Operationen unterzogen wurden, verglichen. Bereits nach dem unterschiedlich langen Transport zeigten die Pferde signifikante Anstiege von Gesamtleukozytenzahl, dem Verhältnis neutrophiler Granulozyten zu Lymphozyten (N:L-Verhältnis), Glukose und den klinischen Parametern (Herzfrequenz, Atemfrequenz, Körpertemperatur). Die IgA-Konzentration im Kot sank bei den eingelieferten Pferden nach Einlieferung erst ab, um sich dann vermutlich durch den Kontakt mit den fremden Antigenen in der Klinik reflektorisch zu erhöhen. Auffällig war, dass die Kortisolkonzentration nach dem Transport bei den als „nervös, sensibel“ eingestuften Pferden signifikant höher lag als bei den „ruhigen, ausgeglichenen“ Pferden. Weitere deutliche Veränderungen zeigten sich nach den Operationen. Glukose, Kortisol und das N:L-Verhältnis wiesen nach den unterschiedlich langen Eingriffen höhere Konzentrationen auf. Die Laktatkonzentration stieg signifikant bereits nach der Operation und anschließend noch weiter nach der Aufstehphase. Dies ist primär auf die Muskelbelastung zurückzuführen, da Laktat vor allem muskulären Ursprungs ist. Hämatokrit und Gesamteiweiß sanken nach der Narkose aufgrund der intraoperativ verabreichten Infusionen ab. Einem starken hoch signifikanten Konzentrationsabfall unterlag auch der IgA-Gehalt im Kot. Dabei war kein Unterschied zwischen den verschiedenen Operationstraumata festzustellen. Ansonsten unterlagen die Pferde, die mit hochgradig gestörtem Allgemeinbefinden zu einer Notoperation eingeliefert wurden, viel deutlicheren Veränderungen als die anderen Pferde. Die Freien Radikale zeigten überhaupt keinen charakteristischen Verlauf. Sie schienen allerdings bei den chronisch erkrankten Pferden erhöht zu sein. Des Weiteren zeigten sie Erhöhungen bei bestimmten Erkrankungen („Equine Motor Neuron Disease“, Hufrehe). Bei den Pferden, die Zylexis® verabreicht bekamen, konnte eine Tendenz zur Verbesserung des Immunstatus nachgewiesen werden. Es fiel ein deutlich höherer Gesamteiweißgehalt auf, der wahrscheinlich auf eine vermehrte Produktion von Immunglobulinen zurückzuführen ist. Außerdem war die Kortisolkonzentration nach der Operation signifikant niedriger. Der IgAGehalt zeigte einen weniger deutlichen Konzentrationsabfall, was aber statistisch nicht belegt werden konnte. Die Untersuchungen zeigten, dass das N:L-Verhältnis und Glukose geeignete Parameter darstellen um zuverlässig den Stress, dem ein Pferd ausgesetzt ist, zu evaluieren. Kortisol ist vorsichtig zu interpretieren, da es großen individuellen Schwankungen ausgesetzt ist. Die Bestimmung von IgA im Kot gibt Aufschluss über den lokalen Immunstatus des Intestinaltrakts. Da es bei allen Pferden postoperativ zu signifikanten Konzentrationsabfällen kam, sind Pferde nach jeder Operation offensichtlich prädisponiert, eine Darmerkrankung, wie beispielsweise Colitis X, zu entwickeln. Kortisol scheint auch Einfluss auf das lokale Immunsystem zu nehmen, da hohe Kortisolwerte mit einem niedrigen IgA-Gehalt im Kot korrelierten. Um die Zusammenhänge der Blutparameter und der Colitis X näher zu erforschen und insbesondere um die „kritischen“ IgA-Konzentrationen zu ermitteln, wären noch weiterführende Untersuchungen aufschlußreich. [Many horses in clinics display symptoms of stress-associated diseases. One of the most feared is the so-called Colitis X, an often fatal ending diarrhea. As death occurs quite often in the course of those diseases, their avoidance has first priority. The aim of the following study was to find out whether signs of stress which are displayed by the horses correlate with measurable blood parameters. Furthermore we tried to find a parameter which was suitable to evaluate stress in hospitalized horses. Apart from the commonly measured parameters (hematocrit, total protein, leucocytes, glucose, lactate, corticosterone) we tried to include free oxygen radicals in this study. Immunoglobulin A in faeces was investigated to find out how stress interfered with the local immune system. A Paramunityinducer often used in Germany (Zylexis®) was administered to 10 selected horses to research its effect on the different parameters. 110 patients hospitalized in the horse clinic were examined. First the horses were organized into two groups. One group underwent surgery and the other one received stationary treatment. Furthermore a control group was taken into account which had not been transported or subjected to stress in six weeks prior to the study. The horses were drawn blood and collected faeces in defined intervals to register the influence of transport, operation and clinic stress. Blood samples were taken directly after the transport, prior to the operation, right after surgery and one day and four days after the operation. Horses which did not undergo surgery including the control group were drawn blood and faeces three times (day 1, 3, and the day prior to discharge from the clinic). For the paramunity investigation patients for vitrectomy were chosen as they display a good example for short little traumatic operations. Those were compared with other horses brought into the clinic for short operations. After the transport to the clinic horses showed significant increases in leukocyte concentration, N:L-ratio, glucose and the clinical parameters (heart rate, breathing rate, body temperature). The immunoglobulin concentration decreased after the transport to rapidly rise after contact with antigens from the clinic environment. Horses categorized as “nervous, sensitive” displayed significantly higher corticosterone concentrations after the transport than horses categorized as “cool, calm”. Other distinct variations showed after the operations. The lactate concentrations increased significantly after anaesthesia and went up even further after the horse got up afterwards. This is due to muscular fatigue as lactate is mainly produced in the muscles. Glucose, corticosterone and the N:L-ratio also displayed higher concentrations after the operation. Hematocrit and total protein concentrations decreased after anaesthesia ascribed to infusions during operation. After anaesthesia a highly significant reduction of immunoglobulin concentrations in the faeces was determined. No influence of the different operation traumas could be recognized. That was surprising as in all other cases horses in very bad general condition displayed distinct changes. The free oxygen radicals did not show any characteristic pattern. There appeared to be a higher concentration in horses with chronic illnesses. Furthermore some diseases, like Equine Motor Neuron Disease and laminitis, seemed to have an increasing impact on the oxygen radicals. Zylexis® showed a tendency to improve the immune status of the horses in this study. The paramunized horses had more total serum protein than the others. This could be due to an increased production of Immunoglobulins. Additionally the corticosterone concentration after the operation stayed on a significantly lower level. The local immunoglobulin A concentrations did not appear to decrease as much as in the non-paramunized horses but it was not possible to statistically prove this statement. The results of this study show that the N:L-ratio and glucose might be suitable parameters to reliably evaluate the stress that has an effect on the hospitalized horse. Corticosterone values have to be interpreted carefully as they are very prone to individual variations. Measuring immunoglobulins in faeces provides information about the local intestinal immune status. Since all horses showed significant lower immunoglobulin concentrations after the anesthesia/operation they obviously lack immune protection and are therefore predisposed for developing enteritis, as Colitis X. In this study corticosterone seemed to influence the local immune system as high concentrations of corticosterone correlated with low immunoglobulin levels. To understand the circumstances more thoroughly and to find out which factors have to be present additionally in order for the horses to fall ill with Colitis X, further investigations have to be made.] |
McBride, S. D., & Wolf, B. (2007). Using multivariate statistical analysis to measure ovine temperament; stability of factor construction over time and between groups of animals. Appl. Anim. Behav. Sci., 103(1-2), 45–58.
Abstract: The ovine arena test in conjunction with multivariate statistical analysis (factor analysis) may be a means of measuring ovine temperament for practical purposes. Stability of factor construction over time and between groups of animals is considered to demonstrate trait consistency and is, therefore, one of the first steps in validating a temperament/personality test from this perspective. The aim of this study, therefore, was to assess the stability of factor construction, as a measure of trait consistency, using arena test data from three groups of animals with one group (Group 1) tested repeatedly over three rounds (twice at 8 months and once at 22 months of age). Group 1 consisted of 193 mule (Bluefaced Leicester Sire x Scottish Blackface/Welsh Speckled Face dam), ewe lambs (8 months old). Groups 2 and 3 consisted of 189 and 185 mules, respectively (14 months old). All animals were tested for 6 min in a 13 m x 3 m arena. Factor analysis (varimax rotation) was performed twice on the behavioural data (latency to bleat, total number of vocalisations, distance travelled, time spent in different areas of the arena and number of times crossing in and out of pertinent areas), initially using all data recorded on a per minute basis (`Per Minute') for all 6 min of the test (10 factors extracted) and then using total values (`Total'), the summation of the 6 min for each behaviour measured (4 factors extracted). Stability of factor loadings between rounds and between groups was tested using Kendall's coefficient of concordance. For the `Per Minute' data, 5 out of the 10 factors showed significant (p < 0.05) concordance between rounds whilst 9 out of 10 factors showed significant (p < 0.05) concordance between groups. All four factors generated from the `Total' data demonstrated significant (p < 0.05) concordance between rounds and between groups. The four factors generated from the `Total' data were considered to be of potential merit for future studies. These factors were named--`conspecific motivation-fear', `conspecific motivation-distress', `activity' and `low conspecific motivation'.
Keywords: Arena test; Factor analysis; Temperament; Sheep
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McCall, C. A. (2007). Making equine learning research applicable to training procedures. Behav. Process., 76(1), 27–28. |
McElreath, R., Luttbeg, B., Fogarty, S. P., Brodin, T., & Sih, A. (2007). Evolution of animal personalities. Nature, 450(7167), E5. |
McGreevy, P. D., & McLean, A. N. (2007). Roles of learning theory and ethology in equitation. Journal of Veterinary Behavior: Clinical Applications and Research, 2(4), 108–118.
Abstract: By definition, ethology is primarily the scientific study of animal behavior, especially as it occurs in a natural environment; applied ethology being the study of animal behavior in the human domain. The terms equine ethology and ethological training are becoming commonplace in the equestrian domain, yet they seem to be used with a conspicuous lack of clarity and with no mention of learning theory. Most of what we do to train horses runs counter to their innate preferences. This article summarizes the ethological challenges encountered by working horses and considers the merits and limitations of ethological solutions. It also questions the use of terms such as “alpha” and “leader” and examines aspects of learning theory, equine cognition, and ethology as applied to horse training and clinical behavior modification. We propose 7 training principles that optimally account for the horse's ethological and learning abilities and maintain maximal responsivity in the trained horse. These principles can be summarized as: (1) use learning theory appropriately; (2) train easy-to-discriminate signals; (3) train and subsequently elicit responses singularly; (4) train only one response per signal; (5) train all responses to be initiated and subsequently completed within a consistent structure; (6) train persistence of current operantly conditioned responses; and (7) avoid and disassociate flight responses. Adherence to these principles and incorporating them into all horse training methodologies should accelerate training success, reduce behavioral wastage of horses, and improve safety for both humans and horses.
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Meehan, C. L., & Mench, J. A. (2007). The challenge of challenge: Can problem solving opportunities enhance animal welfare? Appl. Anim. Behav. Sci., 102(3-4), 246–261.
Abstract: Cognitive mechanisms are an important part of the organization of the behavior systems of animals. In the wild, animals regularly face problems that they must overcome in order to survive and thrive. Solving such problems often requires animals to process, store, retrieve, and act upon information from the environment--in other words, to use their cognitive skills. For example, animals may have to use navigational, tool-making or cooperative social skills in order to procure their food. However, many enrichment programs for captive animals do not include the integration of these types of cognitive challenges. Thus, foraging enrichments typically are designed to facilitate the physical expression of feeding behaviors such as food-searching and food consumption, but not to facilitate complex problem solving behaviors related to food acquisition. Challenging animals by presenting them with problems is almost certainly a source of frustration and stress. However, we suggest here that this is an important, and even necessary, feature of an enrichment program, as long as animals also possess the skills and resources to effectively solve the problems with which they are presented. We discuss this with reference to theories about the emotional consequences of coping with challenge, the association between lack of challenge and the development of abnormal behavior, and the benefits of stress (arousal) in facilitating learning and memory of relevant skills. Much remains to be done to provide empirical support for these theories. However, they do point the way to a practical approach to improving animal welfare--to design enrichments to facilitate the cognitive mechanisms which underlie the performance of complex behaviors that cannot be performed due to the restrictions inherent to the captive environment.
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Mennecke, B. E., Townsend, A. M., Hayes, D. J., & Lonergan, S. M. (2007). A study of the factors that influence consumer attitudes toward beef products using the conjoint market analysis tool. J. Anim Sci., , jas.2006–495-.
Abstract: This study utilizes an analysis technique commonly used in marketing, the conjoint method, to examine the relative utilities of a set of beef steak characteristics considered by a national sample of 1,432 US consumers, as well as additional localized samples representing undergraduate students at a business college and in an animal science department. The analyses indicate that among all respondents, region of origin is by far the most important characteristic; this is followed by animal breed, traceability, animal feed, and beef quality. Alternatively, the cost of cut, farm ownership, the use (or non-use) of growth promoters, and whether the product is guaranteed tender were the least important factors. Results for animal science undergraduates are similar to the aggregate results except that these students emphasized beef quality at the expense of traceability and the non-use of growth promoters. Business students also emphasized region of origin but then emphasized traceability and cost. The ideal steak for the national sample is from a locally produced choice Angus, fed a mixture of grain and grass that is traceable to the farm or origin. If the product was not produced locally respondents indicated that their preferred production states are, in order from most to least preferred, Iowa, Texas, Nebraska and Kansas.
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Meral, Y., Cakiroglu, D., Sancak, A. A., Cyftcy, G., & Karabacak, A. (2007). Relationships between serum serotonin and serum lipid levels, and aggression in horses. Dtsch Tierarztl Wochenschr, 114(1), 30–32.
Abstract: Levels of serum serotonin and serum lipids--triglyceride, total cholesterol, low-density lipoprotein, high-density lipoprotein and very low-density lipoprotein, were determined in normal horses and horses diagnosed with aggression on the basis of a questionnaire survey. Blood serotonin levels in aggressive horses were found to be significantly lower than in non-aggressive horses (P < 0.01), but no association was found with respect to blood lipids.
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Meschan, E. M., Peham, C., Schobesberger, H., & Licka, T. F. (2007). The influence of the width of the saddle tree on the forces and the pressure distribution under the saddle. The Veterinary Journal, 173(3), 578–584.
Abstract: As there is no statistical evidence that saddle fit influences the load exerted on a horse's back this study was performed to assess the hypothesis that the width of the tree significantly alters the pressure distribution on the back beneath the saddle. Nineteen sound horses were ridden at walk and trot on a treadmill with three saddles differing only in tree width. Kinetic data were recorded by a sensor mat. A minimum of 14 motion cycles were used in each trial. The saddles were classified into four groups depending on fit. For each horse, the saddle with the lowest overall force (LOF) was determined. Saddles were classified as “too-narrow” if they were one size (2 cm) narrower than the LOF saddle, and “too-wide” if they were one size (2 cm) wider than the LOF saddle. Saddles two sizes wider than LOF saddles were classified as “very-wide”. In the group of narrow saddles, the pressure in the caudal third (walk 0.63 N/cm2 +/- 0.10; trot 1.08 N/cm2 +/- 0.26) was significantly higher compared to the LOF saddles (walk 0.50 N/cm2 +/- 0.09; trot 0.86 N/cm2 +/- 0.28). In the middle transversal third, the pressure of the wide saddles (walk 0.73 N/cm2 +/- 0.06; trot 1.52 N/cm2 +/- 0.19) and very-wide saddles (walk 0.77 N/cm2 +/- 0.06; trot 1.57 N/cm2 +/- 0.19) was significantly higher compared to LOF saddles (walk 0.65 N/cm2 +/- 0.10/ 0.63 N/cm2 +/- 0.11; trot 1.33 N/cm2 +/- 0.22/1.27 N/cm2 +/- 0.20). This study demonstrates that the load under poorly fitting saddles is distributed over a smaller area than under properly fitting saddles, leading to potentially harmful pressures peaks.
Keywords: Saddle fit; Kinematics; Kinetics; Pressure; Saddletree
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Miller-Butterworth, C. M., Kaplan, J. R., Barmada, M. M., Manuck, S. B., & Ferrell, R. E. (2007). The Serotonin Transporter: Sequence Variation in Macaca fascicularis and its Relationship to Dominance. Behav Genet, .
Abstract: Specific genotypes of the rhesus monkey and human serotonin transporter gene (SERT) promoter region are associated with personality traits and serotonergic activity. However, the most commonly studied promoter polymorphism (5-HTTLPR) is monomorphic in many other monkey species. To date, no systematic search for alternative potentially functional polymorphisms across the remaining coding parts of the gene has been undertaken in other primate species, despite the crucial role SERT plays in modulating serotonergic tone. We investigated whether sequence variation in this gene is associated with social rank and serotonin metabolite (5-HIAA) differences in 524 cynomolgus macaques. Sequence variation and extent of linkage disequilibrium (LD) across the regulatory and coding regions were initially characterized in 92 macaques. The exons and promoter contained 28 polymorphisms, more than double that recorded for human SERT. In further contrast to humans, the macaque SERT showed no significant LD. Potentially functional polymorphisms were genotyped in all animals. No individual variants or haplotypes were significantly associated with social rank or 5-HIAA concentrations; however, certain serotonin transporter diplotypes may modulate acquisition of dominance status.
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