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Kihara, H., Nakatani, H., Hiromi, K., & Hon-Nami, K. (1977). Kinetic studies on redox reactions of hemoproteins. I. Reduction of thermoresistant cytochrome c-552 and horse heart cytochrome c by ferrocyanide. Biochim Biophys Acta, 460(3), 480–489.
Abstract: The oxidation-reduction reaction of horse heart cytochrome c and cytochrome c (552, Thermus thermophilus), which is highly thermoresistant, was studied by temperature-jump method. Ferrohexacyanide was used as reductant. (Formula: see text.) Thermodynamic and activation parameters of the reaction obtained for both cytochromes were compared with each other. The results of this showed that (1) the redox potential of cytochrome c-552, + 0.19 V, is markedly less than that of horse heart cytochrome c. (2) deltaHox of cytochrome c-552 is considerably lower than that of horse heart cytochrome c. (3) deltaSox and deltaSred of cytochrome c-552 are more negative than those of horse heart cytochrome c. (4) kred of cytochrome c-552 is much lower than that of horse heart cytochrome c at room temperature.
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Fazio, E., Medica, P., Cravana, C., Giacoppo, E., & Ferlazzo, A. (2008). Effect of Short-Distance Road Transport on Thyroid Function, Rectal Temperature, Body Weight and Heart Rate of Stallions. In IESM 2008.
Abstract: Aim of study was to investigate the effects of transport stress on thyroid response, body weight, rectal temperature and heart rate changes in one hundred twenty-six healthy stallions in basal conditions, before and after short road transport. One hundred twenty-six Thoroughbreds and crossbreds stallions with previous travelling experience, aged 4 to 15 yr, were transported by road in a commercial trailer for a period of 3 h (distance <300 km). Blood samples and physiological parameters were collected at 0800 (basal I) and at 1100 (basal II), in each horse“s box, one week before the loading and transport in basal conditions, and one week later, at 0800 immediately before loading (pre-transport), and after 3 h period of transport and unloading, on their arrival at the breeding stations (post-transport), in each new horse”s box, within 30 min. Increases in circulating T3, T4 and fT4 levels (P < 0.01), but not for fT3 levels, were observed after transport, as compared to before loading values, irrespective of different breed. Lower T4 and fT4 levels were observed in basal II (P < 0.01) than basal I and before loading values (pre-transport). After transport Thoroughbreds showed higher fT3 (P < 0.05) and fT4 (P < 0.01) levels than crossbred stallions. No significant differences for T3 and T4 changes were observed. A significant increase in rectal temperature (P < 0.01) and heart rate (P < 0.05) was observed after transport, as compared to before loading values (pre-transport). No differences between basal I, basal II and before loading values (pre-transport) for physiological parameters were observed.
The highest T3, T4 and fT4 levels recorded after short transport seem to suggest a preferential release from the thyroid gland. The results indicate that short road transport stress contributes significantly to thyroid hormone changes, according to different breed, and to the increase in rectal temperature and heart rate. No differences related to different age were observed.
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Brinkmann, L., Gerken, M., & Riek, A. (2015). Energetic adaptations of Shetland pony mares. In Proceedings of the 3. International Equine Science Meeting.
Abstract: Recent results suggest that wild Northern herbivores exhibit signs of a hypometabolism during times of low ambient temperature and food shortage in order to reduce their energetic needs. However, there are speculations that domestic animals lost the ability to reduce energy expenditure. To examine energetic and behavioural responses 10 Shetland pony mares were exposed to different environmental conditions (summer and winter). During winter ponies were allocated into two groups receiving two different food quantities (60% and 100% of maintenance energy requirement). We measured the field metabolic rate, water turn over, body temperature, locomotor activity, lying time, resting heart rate, body mass and body condition score.
In summer, the field metabolic rate of all ponies (FMR; 63.4±15.0 MJ/day) was considerably higher compared with food restricted and control animals in winter (24.6±7.8 and 15.0±1.1 MJ/day, respectively). Furthermore, during summer, locomotor activity, resting heart rate and total water turnover were significantly elevated (P<0.001) compared with winter. Animals receiving a reduced amount of food (N=5) reduced their FMR by 26% compared with control animals (N=5) to compensate for the decreased energy supply. Furthermore, resting heart rate, body mass and body condition score were lower(29.2±2.7 beats/min, 140±22 kg and 3.0±1.0 points, respectively) than in control animals (36.8±41 beats/min, 165±31 kg, 4.4±0.7 points; P<0.05). While no difference could be found in the observed behaviour, nocturnal hypothermia was elevated in restrictively fed animals. Our results indicate that ponies adapt to different climatic conditions by changing their metabolic rate, behaviour and some physiological parameters. When exposed to energy shortage, ponies, like wild herbivores, exhibited hypometabolism and nocturnal hypothermia.
Keywords:
Body temperature, Energy expenditure, Food restriction, Hypometabolism, Locomotor activity, Shetland pony
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Oliveira-Santos, L. G. R., Machado-Filho, L. C. P., Tortato, M. A., & Brusius, L. (2010). Influence of extrinsic variables on activity and habitat selection of lowland tapirs (Tapirus terrestris) in the coastal sand plain shrub, southern Brazil. Mammalian Biology – Zeitschrift für Säugetierkunde, 75(3), 219–226.
Abstract: The objectives of this research were to: 1. evaluate the circadian activity patterns of lowland tapirs (Tapirus terrestris) throughout the seasons and 2. study the influence of moonlight, temperature and rainfall on the activity patterns and habitat selection of this species, in the coastal sand shrub in southern Brazil. From June 2005 to June 2006, eight tapirs were monitored in a large enclosure containing open and vegetation-covered areas, using four camera traps. Differences in activity patterns within seasons were found. Tapir predominately presented nocturnal-crepuscular activity; however, they differed in the winter, with cathemeral activity patterns. Covered areas were mostly used during periods of extreme temperatures, with less diurnal and more nocturnal activities within these areas, on hotter days. Activity in open areas mainly occurred during periods of intermediate temperatures, both during the day and in the night. Moonlight intensity did not influence nocturnal activities. On days of precipitation of 34 mm or more, there was no record of open-area activities, despite constant activity in covered-area.
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Yarnell, K., Hall, C., & Billett, E. (2013). An assessment of the aversive nature of an animal management procedure (clipping) using behavioral and physiological measures. Physiol. Behav., 118, 32–39.
Abstract: Animal management often involves procedures that, while unlikely to cause physical pain, still cause aversive responses. The domestic horse (Equus caballus) regularly has excessive hair clipped off to facilitate its use as a riding/driving animal and this procedure causes adverse behavioral responses in some animals. The aim of this study was to compare behavioral and physiological measures to assess the aversive effect of this procedure. Ten horses were selected on the basis of being either compliant (C: n=5) or non-compliant (NC: n=5) during this procedure. The horses were subjected to a sham clipping procedure (SC: where the blades had been removed from the clippers) for a period of ten minutes. Measures were taken pre, during and post SC (-10min to +30min) and mean values calculated for ALL horses and for C and NC separately. Behavioral activity was scored (scale 1-5) by twenty students from video footage in (phase/group-blind scoring). Heart rate (HR), salivary cortisol and eye temperature were monitored throughout the procedure. The NC horses were found to be significantly more behaviorally active/less relaxed throughout the trial than C horses (p<0.05) with the greatest difference occurring during the SC procedure (p<0.01). NC horses were more active/less relaxed during, compared with pre or post SC (p<0.05), but showed no behavioral difference pre and post SC. HR of the NC horses was higher than that of the C horses throughout the trial but only significantly so after 10min of SC (p<0.01). ALL horses showed a significant increase in HR between +5 and +10min into the procedure (p<0.05). There was a significant increase in salivary cortisol concentration in ALL horses post procedure (p<0.01) with levels peaking at 20minute post SC. No significant differences in salivary cortisol concentration between C and NC were found at any stage of the trial. Eye temperature increased significantly in ALL horses during SC, peaking at +10min into the procedure (p<0.05) and then decreased substantially when SC had ceased (p<0.01). Although no significant differences were found between C and NC per se, there was a significant interaction between group and phase of trial (p<0.05) with the NC group showing a greater decrease in eye temperature post SC. There was a significant positive correlation between changes in salivary cortisol concentration and eye temperature (p<0.01) but no correlation between any of the other measures. Although the behavioral response of C and NC to this procedure was significantly different the physiological responses indicated that ALL horses found the procedure aversive. Eye temperature could be used as an objective and immediate measure of how an animal is responding to a specific situation in order to evaluate management procedures and adapt them where appropriate to reduce the negative impact on animal health and welfare.
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Morgan, K., Funkquist, P., & Nyman, G. (2002). The effect of coat clipping on thermoregulation during intense exercise in trotters. Equine Veterinary Journal, 34(S34), 564–567.
Abstract: Summary The aim of this study was to study the physiological, especially thermoregulatory, responses during intense exercise in the clipped horse compared to the horse with winter coat. Six Standardbred trotters were studied before and after clipping. They performed an inclined incremental high intensity treadmill exercise test and were monitored during recovery. The clipped horse differed significantly (ANOVA) during exercise as compare to coated: less increase in central venous blood temperature, higher skin surface temperature, greater difference skin to ambient temperature and higher rate of nonevaporative heat loss. The clipped horse had significantly lower total cutaneous evaporative heat loss from walk to end of peak exercise and a shorter time for recovery for the respiratory rate using a paired t test. The clipped horse showed a tendency (P = 0.059) to decreased oxygen uptake during the stepwise increase in workload. We concluded that the clipped horse experienced less strain on the thermoregulatory system due to an enhanced heat loss. Some clipped horses in the study showed a more efficient power output; future studies with emphasis on respiration and oxygen demand are needed to explain this.
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