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Author |
Kirkpatrick, J.F.; Turner, A. |
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Title |
Reversibility of action and safety during pregnancy of immunization against porcine zona pellucida in wild mares (Equus caballus) |
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Journal Article |
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Year |
2002 |
Publication |
Reproduction (Cambridge, England) Supplement |
Abbreviated Journal |
Reprod Suppl |
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Volume |
60 |
Issue |
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Pages |
197-202 |
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Keywords  |
Animals; *Animals, Wild; Antigens/administration & dosage; Contraception, Immunologic/methods/*veterinary; Egg Proteins/administration & dosage; Female; Fertility; *Horses; Immunization, Secondary/veterinary; Membrane Glycoproteins/administration & dosage; Population Control; Pregnancy; *Receptors, Cell Surface; Safety; Swine; Time Factors; Vaccines, Contraceptive/*administration & dosage |
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Abstract |
Contraceptive management of publicly valued wildlife species requires safeguards to ensure that these populations are preserved in a healthy state. In addition, reversibility of contraceptive effects and safety in pregnant animals are major concerns. A population of wild horses has been immunized against porcine zona pellucida (PZP) over a 12 year period on Assateague Island National Seashore, MD (ASIS). Mares initially received one or two 65 microg inoculations and once a year 65 microg booster inoculations, all delivered by dart. All young mares aged > 2 years were treated with PZP for 3 consecutive years regardless of whether they have bred successfully and they were then removed from treatment until they had foaled. All mares vaccinated for 1 or 2 consecutive years became fertile again and 69% of mares treated for 3 consecutive years returned to fertility. All five mares treated for 4 or 5 consecutive years have also returned to fertility, but over longer periods of time. Mares treated for 7 consecutive years have not returned to fertility, but several, while still infertile, have started ovulating again. There was no difference in survival rates between foals born to treated and untreated mares, and PZP treatment of pregnant mares did not affect subsequent fertility of their female offspring. |
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Science and Conservation Center, ZooMontana, Billings 59106, USA. zoolab@wtp.net |
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1477-0415 |
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PMID:12220160 |
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refbase @ user @ |
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141 |
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Author |
Huebener, E. |
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Title |
The Rider's Impacts and Their Timers – Example: Rider's Aids for Transitions Between Different Gaits. |
Type |
Journal Article |
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Year |
2006 |
Publication |
Tierärztliche Umschau |
Abbreviated Journal |
Tierärztl. Umschau |
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Volume |
10 |
Issue |
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Pages |
515-532 |
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Keywords |
Animal-friendly rider-horse communication – signals for changing the footfall – knee-jerk impacts in the single “fitting” moment – singular timer for those – immediate “obedience” |
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Abstract |
The scientific investigation of the basics of the inherited riding teachings assists in conserving its values. Riding instructors should be able to teach not only “how” but also “why”.
The classic European riding teachings that have developed across the centuries are based on perceptions that have their roots in natural phenomena. They are being mirrored, for instance, in the aids to stimulate the change from one gait to the next.
The movements of the horse's trunk and back provide timers for horse-friendly, sensitive aids that create attentive, diligent and happily cooperating horses. |
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German |
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yes |
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refbase @ user @ |
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434 |
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Author |
McGreevy, P.D.; Cripps, P.J.; French, N.P.; Green, L.E.; Nicol, C.J. |
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Title |
Management factors associated with stereotypic and redirected behaviour in the thoroughbred horse |
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Journal Article |
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Year |
1995 |
Publication |
Equine veterinary journal |
Abbreviated Journal |
Equine Vet J |
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Volume |
27 |
Issue |
2 |
Pages |
86-91 |
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Keywords |
Animal Husbandry/*methods; Animals; Horse Diseases/psychology/*therapy; Horses; Risk Factors; *Stereotyped Behavior; Time Factors |
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Abstract |
A greater knowledge of the effect of management factors is required to investigate the ontogeny of abnormal behaviour in the stabled horse. A postal survey of racehorse (flat) trainers yielded information about 22 yard and management factors. The relationship of the factors to the prevalence of abnormal behaviour was analysed by logistic regression. Management factors related to the time spent in the stable showed the strongest associations with stereotypic behaviour. The risk of horses performing abnormal behaviour increased: 1) as the amount of forage fell below 6.8 kg/day, 2) when bedding types other than straw were used, 3) when the total number of horses on the yard was fewer than 75, 4) in association with box designs that minimised contact between neighbouring horses, 5) when hay, rather than other types of forage, was used. |
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Department of Animal Health and Husbandry, School of Veterinary Science, University of Bristol, Langford, UK |
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0425-1644 |
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Notes |
PMID:7607155 |
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no |
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Call Number |
refbase @ user @ |
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91 |
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Author |
Clayton, H.M. |
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Title |
Classification of collected trot, passage and piaffe based on temporal variables |
Type |
Journal Article |
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Year |
1997 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
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Volume |
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Issue |
23 |
Pages |
54-57 |
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Keywords |
Analysis of Variance; Animals; Discriminant Analysis; Gait/*physiology; Hindlimb/physiology; Horses/*physiology; Locomotion/*physiology; Male; Running/physiology; Time Factors; Videotape Recording; Walking/physiology |
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The objective was to determine whether collected trot, passage and piaffe could be distinguished as separate gaits on the basis of temporal variables. Sagittal plane, 60 Hz videotapes of 10 finalists in the dressage competitions at the 1992 Olympic Games were analysed to measure the temporal variables in absolute terms and as percentages of stride duration. Classification was based on analysis of variance, a graphical method and discriminant analysis. Stride duration was sufficient to distinguish collected trot from passage and piaffe in all horses. The analysis of variance showed that the mean values of most variables differed significantly between passage and piaffe. When hindlimb stance percentage was plotted against diagonal advanced placement percentage, some overlap was found between all 3 movements indicating that individual horses could not be classified reliably in this manner. Using hindlimb stance percentage and diagonal advanced placement percentage as input in a discriminant analysis, 80% of the cases were classified correctly, but at least one horse was misclassified in each movement. When the absolute, rather than percentage, values of the 2 variables were used as input in the discriminant analysis, 90% of the cases were correctly classified and the only misclassifications were between passage and piaffe. However, the 2 horses in which piaffe was misclassified as passage were the gold and silver medallists. In general, higher placed horses tended toward longer diagonal advanced placements, especially in collected trot and passage, and shorter hindlimb stance percentages in passage and piaffe. |
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Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada |
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Notes |
PMID:9354290 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
3738 |
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Author |
Murray, J.K.; Senior, J.M.; Singer, E.R. |
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Title |
A comparison of cross-country recovery rates at CCI 2* with and without steeplechase competitions |
Type |
Journal Article |
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Year |
2006 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
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Volume |
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Issue |
36 |
Pages |
133-138 |
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Keywords |
Analysis of Variance; Animals; Area Under Curve; Blood Chemical Analysis/veterinary; Blood Gas Analysis/veterinary; Calcium/blood; Heart Rate/physiology; Hematocrit/veterinary; Horses/*blood/*physiology; Lactates/blood; Physical Conditioning, Animal/*methods/*physiology; Time Factors |
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Abstract |
REASONS FOR PERFORMING STUDY: Short format 3-day events were introduced in 2004. Anecdotal reports suggested that horses were more tired on completion of the cross-country phase of short format events when compared with horses completing the cross-country phase of long format competitions, despite the absence of Phases A, B and C. OBJECTIVES: To compare the physiological parameters and haematological parameters of horses that had completed the cross-country phase of a short format (SF) and a long format (LF) CCI 2* competition. METHODS: During a CCI 2* competition 69 competitors took part in the short format and 74 in the long format competition. Long format competitors completed Phases A, B, C and D and short format competitors completed Phase D only. Phase D (the cross-country course) was identical for both competitions. Two-way ANOVA for repeated measures and post hoc tests were used to compare temperature, pulse and respiration rates of horses competing in both types of competition. T tests were used to compare mean lactate and electrolyte concentrations, while U-Mann Whitney tests were used to compare CK and AST levels measured in horses competing in the short and long formats of the event. RESULTS: Training schedules, age and previous competition experience were not significantly different between horses competing in the SF and LF competitions. On completion of Phase D, SF horses had significantly higher PCV and significantly lower ionised calcium concentrations when compared with LF horses. LF horses had significantly higher heart rates than SF horses 10 min prior to starting Phase D and immediately after completing Phase D; however, no other significant differences were found between the 2 groups of horses. CONCLUSIONS: Only weak evidence was found to support the hypothesis that the workload for the horse in a SF CCI 2* competition is significantly different when compared to the LF CCI 2* competition. POTENTIAL RELEVANCE: There is no beneficial or detrimental effect on horses that complete short format CCI 2* competitions as compared to those that complete long format CCI 2* competitions but further research is required into the physiological response of horses at CCI 3* and CCI 4* short format competitions. |
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Department of Veterinary Clinical Science, University of Bristol, Langford House, Langford, Bristol, UK |
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Notes |
PMID:17402408 |
Approved |
no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
4011 |
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Author |
Lewis, K.P.; Jaffe, S.; Brannon, E.M. |
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Title |
Analog number representations in mongoose lemurs (Eulemur mongoz): evidence from a search task |
Type |
Journal Article |
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Year |
2005 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
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Volume |
8 |
Issue |
4 |
Pages |
247-252 |
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Keywords |
Analysis of Variance; Animals; *Behavior, Animal; *Feeding Behavior; Female; Lemuridae/*psychology; Male; Mathematics; Odors; Smell/physiology; Time Factors |
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Abstract |
A wealth of data demonstrating that monkeys and apes represent number have been interpreted as suggesting that sensitivity to number emerged early in primate evolution, if not before. Here we examine the numerical capacities of the mongoose lemur (Eulemur mongoz), a member of the prosimian suborder of primates that split from the common ancestor of monkeys, apes and humans approximately 47-54 million years ago. Subjects observed as an experimenter sequentially placed grapes into an opaque bucket. On half of the trials the experimenter placed a subset of the grapes into a false bottom such that they were inaccessible to the lemur. The critical question was whether lemurs would spend more time searching the bucket when food should have remained in the bucket, compared to when they had retrieved all of the food. We found that the amount of time lemurs spent searching was indicative of whether grapes should have remained in the bucket, and furthermore that lemur search time reliably differentiated numerosities that differed by a 1:2 ratio, but not those that differed by a 2:3 or 3:4 ratio. Finally, two control conditions determined that lemurs represented the number of food items, and neither the odor of the grapes, nor the amount of grape (e.g., area) in the bucket. These results suggest that mongoose lemurs have numerical representations that are modulated by Weber's Law. |
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Department of Anthropology, Washington University, St. Louis, MO 63130-4899, USA |
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1435-9448 |
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Notes |
PMID:15660208 |
Approved |
no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2497 |
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Author |
Kristiansen, K.K.; Kold, S.E. |
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Title |
Multivariable analysis of factors influencing outcome of 2 treatment protocols in 128 cases of horses responding positively to intra-articular analgesia of the distal interphalangeal joint |
Type |
Journal Article |
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Year |
2007 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
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Volume |
39 |
Issue |
2 |
Pages |
150-156 |
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Keywords |
Analgesia/methods/*veterinary; Anesthesia, Local/methods/veterinary; Animals; Anti-Inflammatory Agents/therapeutic use; Female; Foot Diseases/drug therapy/prevention & control/*veterinary; Glycosaminoglycans/therapeutic use; Horse Diseases/*drug therapy/prevention & control; Horses; Injections, Intra-Articular/*veterinary; Joint Diseases/drug therapy/prevention & control/veterinary; Lameness, Animal/drug therapy/prevention & control; Male; Methylprednisolone/analogs & derivatives/therapeutic use; Multivariate Analysis; Pain/prevention & control/veterinary; Retrospective Studies; Time Factors; *Toe Joint/drug effects/pathology; Treatment Outcome |
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Abstract |
REASONS FOR PERFORMING STUDY: There is limited knowledge available of factors influencing response to treatments of the DIP-joint in horses with lameness responding to diagnostic analgesia of the DIP-joint. For this reason a multivariable statistical analysis was performed. HYPOTHESIS: Horses with lameness reduced by > or = 75% 10 min after intra-articular analgesia of the DIP-joint, can be treated successfully by intra-articular medication of the joint. Multiple factors influence the response to treatment. METHODS: The study was performed retrospectively based on clinical records of horses treated with either polysulphated glycosaminoglycan (PSGAG) or methylprednisolone acetate (MPA) in the DIP-joint between January 1996 and January 2003. Information was collected from clinical records and from the owners of the horses via a detailed questionnaire, in which they described their perception of the outcome a minimum of one year after treatment. Allocation of the horses to the 2 treatment groups was done mainly because of a change in treatment policy. In Regime A all horses received 3 intra-articular injections of PSGAG approximately 8 days apart, whereas in Regime B all horses received a single intra-articular injection of MPA as a first treatment. If the horse did not improve sufficiently to return to work by 4 weeks, a series of 3 intra-articular PSGAG injections was administered. RESULTS: Of the horses receiving Regime A, 67% had a successful outcome, compared with 46% of the group receiving Regime B. A significantly better result was obtained in dressage horses than in jumping horses (eventing and showjumping). Other variables such as age, duration of lameness, distribution of lameness, degree of lameness, response to DIP-joint analgesia and radiographic observations were also associated with success of treatment. CONCLUSIONS AND POTENTIAL RELEVANCE: There is a rationale for using either PSGAG or MPA intra-articularly in the treatment of lameness, reduced > or = 75% within 10 min of analgesia of the DIP-joint. |
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Willesley Equine Clinic Ltd., Tetbury, Gloucestershire, GL8 8QU UK |
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0425-1644 |
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Notes |
PMID:17378444 |
Approved |
no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
3707 |
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Author |
Blokland, A. |
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Title |
Reaction time responding in rats |
Type |
Journal Article |
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Year |
1998 |
Publication |
Neuroscience and Biobehavioral Reviews |
Abbreviated Journal |
Neurosci Biobehav Rev |
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Volume |
22 |
Issue |
6 |
Pages |
847-864 |
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Keywords |
Amphetamine/pharmacology; Animals; Behavior, Animal/drug effects/*physiology; Conditioning, Operant/drug effects/*physiology; Dopamine Uptake Inhibitors/pharmacology; Dose-Response Relationship, Drug; Male; Rats; Rats, Inbred Lew; Reaction Time/drug effects/*physiology |
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Abstract |
The use of reaction time has a great tradition in the field of human information processing research. In animal research the use of reaction time test paradigms is mainly limited to two research fields: the role of the striatum in movement initiation; and aging. It was discussed that reaction time responding can be regarded as “single behavior”, this term was used to indicate that only one behavioral category is measured, allowing a better analysis of brain-behavior relationships. Reaction time studies investigating the role of the striatum in motor functions revealed that the initiation of a behavioral response is dependent on the interaction of different neurotransmitters (viz. dopamine, glutamate, GABA). Studies in which lesions were made in different brain structures suggested that motor initiation is dependent on defined brain structures (e.g. medialldorsal striatum, prefrontal cortex). It was concluded that the use of reaction time measures can indeed be a powerful tool in studying brain-behavior relationships. However, there are some methodological constraints with respect to the assessment of reaction time in rats, as was tried to exemplify by the experiments described in the present paper. On the one hand one should try to control for behavioral characteristics of rats that may affect the validity of the parameter reaction time. On the other hand, the mean value of reaction time should be in the range of what has been reported in man. Although these criteria were not always met in several studies, it was concluded that reaction time can be validly assessed in rats. Finally, it was discussed that the use of reaction time may go beyond studies that investigate the role of the basal ganglia in motor output. Since response latency is a direct measure of information processing this parameter may provide insight into basic elements of cognition. Based on the significance of reaction times in human studies the use of this dependent variable in rats may provide a fruitful approach in studying brain-behavior relationships in cognitive functions. |
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Department of Psychology, University of Maastricht, The Netherlands |
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0149-7634 |
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Notes |
PMID:9809315 |
Approved |
no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2807 |
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Author |
Czerlinski, G.H.; Wagner, M.; Erickson, J.O.; Theorell, H. |
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Title |
Chemical relaxation studies on the system liver alcohol dehydrogenase, NADH and imidazole |
Type |
Journal Article |
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Year |
1975 |
Publication |
Acta Chemica Scandinavica. Series B: Organic Chemistry and Biochemistry |
Abbreviated Journal |
Acta Chem Scand B |
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Volume |
29 |
Issue |
8 |
Pages |
797-810 |
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Keywords |
Alcohol Oxidoreductases/*metabolism; Animals; Computers; Hydrogen-Ion Concentration; Imidazoles/*metabolism; Kinetics; Liver/enzymology/*metabolism; Mathematics; Models, Chemical; NAD/*metabolism; Time Factors |
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Abstract |
Several years ago, Theorell and Czerlinski conducted experiments on the system of horse liver alcohol dehydrogenase, reduced nicotinamide adenine dinucleotide and imidazole, using the first version of the temperature jump apparatus with detection of changes in fluorescence. These early experiments were repeated with improved instrumentation and confirmed the early experiments in general terms. However, the improved detection system allowed to measure a slight concentration dependence of the relaxation time of around 3 ms. Furthermore, the chemical relaxation time was smaller than the one determined earlier (by factor 2). The data were evaluated much more rigorously than before, allowing an appropriate interpretation of the results. The observed relaxation time is largely due to rate constants in an interconversion of ternary complexes, which are faster than three (of the four) dissociation rate constants, determined previously by Theorell and McKinley-McKee.1,2 This fact contributed to earlier difficulties of finding any concentration dependence. However, the binding of imidazole to the binary enzyme-coenzyme complex can be made to couple kinetically into the interconversion rate of the two ternary complexes. The observed signal derives largely from the ternary complex(es). A substantial fluorescence signal change is associated with the observed relaxation process, suggesting a relocation of the imidazole in reference to the nicotinamide moiety of the bound coenzyme. Nine models are considered with two types of coupling of pre-equilibria (none-all). Quantitative evaluations favor the model with two ternary complexes connected by an interconversion outside the four-step (bimolecular) cycle. The ternary complex outside the cycle has much higher fluorescence yield than the one inside. The interconversion equilibrium is near unity for imidazole. If it would be shifted very much to the side of the “dead-end” complex (as in isobutyramide?!), stimulating action could not take place. |
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0302-4369 |
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Notes |
PMID:882 |
Approved |
no |
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Call Number |
refbase @ user @ |
Serial |
3887 |
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Author |
Czerlinski, G.H.; Erickson, J.O.; Theorell, H. |
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Title |
Chemical relaxation studies on the horse liver alcohol dehydrogenase system |
Type |
Journal Article |
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Year |
1979 |
Publication |
Physiological Chemistry and Physics |
Abbreviated Journal |
Physiol Chem Phys |
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Volume |
11 |
Issue |
6 |
Pages |
537-569 |
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Keywords |
Alcohol Oxidoreductases/*metabolism; Animals; Buffers; Electron Transport; Ethanol/metabolism; Horses; Hydrogen-Ion Concentration; Liver/*enzymology; Mathematics; NAD/metabolism; Oscillometry; Osmolar Concentration; Temperature; Time Factors |
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Abstract |
Chemical relaxation studies on the system horse liver alcohol dehydrogenase, nicotinamide adenine dinucleotide, and ethanol were conducted observing fluorescence changes between 400 and 500 nm. Temperature-jump experiments were performed at pH 6.5, 7.0, 8.0, and 9.0; concentration-jump experiments at pH 9.0. The reciprocal of the slowest relaxation time was found to be linearly dependent upon the enzyme concentration for relatively low enzyme concentrations, as predicted earlier. Use of the wide pH-range necessitated expression of the four apparent dissociation constants of the catalytic reaction cycle in terms of pH-independent constants. The system was described in terms of only one (or two) catalysis-linked protons not associated with the electron transfer. Protonic steps in a buffered system are in rapid equilibrium, too fast to be measured with the equipment available. Assuming only two of the four bimolecular reaction steps in the four-step cycle are fast compared to the remaining two, six cases may be considered with six expressions for the reciprocal of the slowest relaxation time. Comparison with the experimental data revealed that the bimolecular reaction steps governing the slowest relaxation time change with pH. Above the effective time resolution of the temperature-lump instrument with fluorescence detection (0.1 msec) only one other relaxation time was detectable and only at pH 9. This relaxation time, found to be independent of the concentration of all reactants within experimental error (r = 10 +/- 5 msec), is most likely due to an interconversion among ternary complexes. |
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English |
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0031-9325 |
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PMID:44918 |
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Equine Behaviour @ team @ |
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3813 |
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