Abstract: There is a paucity of research relating to the anatomy and physiology of gustation and olfaction in the horse. Moreover, whilst an age-related decline in gustation and olfaction has been recorded in humans, no such study has been conducted in the horse. The horse is reliant on gustation and olfaction to make appropriate decisions relating to both short and long term diet selection and thus, any compromise in function, has implications for food intake and potentially welfare. The principal aim of this study was to establish if, and to what extent, taste andgustatory responses are affected by age in the horse. Horses were allocated to the age groups Young (2-5 years), Middle (8-14 years) and Old (16 plus years) for the study of taste (n=18) and to Young (4-6 years), Middle (10-14 years) and Old (16 plus years) for the study of gustation (n=18). Individual taste responses and gustatory responses (taste in the absence of additional olfactory cues) were identified using two-choice preference testing and monadic testing. Statistical analysis was conducted using Minitab 14.0 and behaviour data was analysed using The Observer 5.0 (Noldus, Netherlands). No effect of age on taste response or gustatory response was recorded.

Abstract: This study was designed to test the hypothesis that there is no significant difference in selected temporal and linear stride variables of the extended canter in horses bred and trained for dressage or racing. Nine advanced-level dressage horses and 7 Thoroughbred racehorses were filmed at a frame rate of 200 Hz at an extended canter on a sand track. Two strides were recorded per trial, and each horse performed 6 or 7 trials. Temporal and linear data were determined from the films, and descriptive statistics (mean, SD) were calculated. Strides were selected for analysis on the basis of having a velocity in the range of 6.0-7.0 m/s, and multivariate analysis of variance was used to detect significant differences in the stride kinematics of horses trained for the two sports (p < or = 0.01). The average velocity of the dressage horses was 6.37 m/s, compared with 6.40 m/s for the racehorses. There were no significant differences between the two groups in velocity, stride duration, stride length or the distances between limb placements. The stance durations of all four limbs and the overlaps between them were longer, whereas the duration of the suspension phase was shorter in the dressage horses than in the racehorses (p < or = 0.01). The time between impacts of the diagonal limb pair was close to zero in both groups, with individual horses showing some variability in the order of placement of the diagonal limb pair. However, the sequence of footfalls was not significantly different between the two groups (p < or = 0.01).

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.

Abstract: Während einer fünftägigen Gotthardüberquerung im Sommer 2016 haben drei Maultiere als Tragtiere mit einer Gepäcklast von je 80 kg rund 94,46 Kilometer und 3&#65533;364 Höhenmeter bewältigt. Die Leistungsanforderung wurde anhand der Erholungswerte der Vitalparameter Herzfrequenz, Atemfrequenz und Körpertemperatur, sowie durch kontinuierliche Herzfrequenzmessung während der Belastung evaluiert. Die Bestimmung der Glucokortikoid- Metabolit Konzentration im Kot diente zur Einschätzung des Stresslevels der drei Maultiere. Die Erholungswerte der Herzfrequenzen der drei Maultiere lagen während allen Trekkingetappen in einem Bereich, der nicht auf eine Leistungsüberforderung schliessen liess. Anhand der kontinuierlichen Herzfrequenzaufzeichnung bei einem der Maultiere konnte gezeigt werden, dass die physische Leistungsanforderung im Ausdauerbereich lag. Wie als normale physiologische Reaktion des Körpers nach einer fünftägigen körperlichen Belastung erwartet, stieg Stresslevel gemessen an den Glucokortikoid- Metaboliten im Kot gegen Ende des Trecks bei allen Maultieren an. In der vorliegenden Studie konnte gezeigt werden, dass die Maultiere während des Gotthardtrecks ausdauernd belastbar waren, ohne durch die Anstrengung beeinträchtigt zu sein, die schon historisch von Maultieren abverlangt wurde.[
Durant une traversée du Gothard de cinq jours pendant l&#65533;été 2016, trois mulets ont été employés comme animaux de bât pour porter une charge de 80 kg sur 94,46 km, avec un dénivelé de 3364 m. Les exigences de performance ont été évaluées à partir des valeurs de récupération des paramètres vitaux (fréquence cardiaque, fréquence respiratoire et température corporelle) et de la fréquence cardiaque durant l&#65533;effort. La concentration en métabolites glucocorticoïdes dans le crottin a permis d&#65533;estimer le niveau de stress des trois animaux. Durant toute la durée du trek, les valeurs de récupération de la fréquence cardiaque des trois mulets étaient comprises dans un intervalle n&#65533;indiquant aucun effort excessif. La mesure constante des pulsations cardiaques a montré que l&#65533;intensité des performances physiques de ces animaux ne sortait pas de leur zone d&#65533;endurance. Comme on pouvait s&#65533;y attendre, le niveau de stress mesuré par le biais des métabolites glucocorticoïdes a augmenté chez tous les mulets à la fin du trek, réaction physiologique normale du corps après un effort de cinq jours. La présente étude a montré que durant un trek sur le Gothard, les mulets ont fait preuve d&#65533;endurance et de résistance, sans altération due à l&#65533;effort que l&#65533;on exige traditionnellement de leur part.][Nell&#65533;estate del 2016 tre muli impiegati come animali da soma hanno attraversato il Gottardo portando un carico di 80 kg ciascuno e percorrendo in cinque giorni un percorso di circa 94,46 chilometri con un dislivello di 3364 metri. La prestazione è stata valutata sulla base dei valori di recupero dei parametri vitali (frequenza cardiaca, frequenza respiratoria, temperatura corporea) e misurando costantemente la frequenza cardiaca sotto sforzo. Il livello di stress dei tre muli è stato valutato in funzione della concentrazione di metaboliti glicocorticoidi riscontrata nelle feci. In tutte le tappe del trekking i valori di recupero della frequenza cardiaca registrati nei muli rientravano in un intervallo che non lasciava supporre un sovraccarico. Sulla base della registrazione costante della frequenza cardiaca di uno dei tre muli è stato possibile dimostrare che l&#65533;intensità dello sforzo fisico non superava il loro intervallo di resistenza. Come previsto, verso la fine del trekking la concentrazione di metaboliti glicocorticoidi nelle feci di tutti e tre i muli indicava un aumento del livello di stress; si tratta di una reazione fisiologica normale dopo uno sforzo fisico di cinque giorni. Questo studio ha dimostrato che lo sforzo sopportato dai muli per portare un carico attraverso il Gottardo, un compito da secoli richiesto a questi animali, rientrava nel loro intervallo di resistenza e non ha avuto ripercussioni negative sul loro fisico.][In the summer of 2016, three pack mules, each carrying a load weighing 80kg, accompanied a 94.46km trek across the Gotthard Pass with a total altitude difference of 3,364m. The mules&#65533; performances were evaluated by measuring vital recovery parameters such as heart- and respiratory rates and body temperature, and by continuous heartrate monitoring during the trek. The stress levels of the animals were estimated by determining glucocorticoid metabolite levels in their faeces. Throughout the trekking days, recovery heartrates lay within a range which indicated that the animals were not being overworked. The continuous heartrate monitoring of one of the mules showed that its physical performance lay within the endurance zone. As expected, glucocorticoid metabolite levels were elevated in the faeces of all the mules &#65533; a normal physiological response after five consecutive days of exercise. The study shows the mules as being capable of performing at an endurance level during the Gotthard trek with no adverse affects on their health &#65533; a performance which was historically expected of the animals.]