Energetic requirements and physiological adaptation of draught horses to ploughing work

Abstract

Five Chilean crossbred draught horses were used to study variation in work performance and biochemical and physiological parameters whilst working with a mould board plough (36 kg) for 6 h/day. The draught force, distance travelled, work done and the estimated extra energy for work were determined for each horse. The results showed that the horses used only 68-0 (s.e. 1-9)% of the total available working time ploughing a mean area of 3283 (s.e. 168) m 2 with a mean depth and width of furrow of 12-6 and 22-3 cm, respectively. Estimated daily energy expenditure by the horses during work was 2-24 (s.e. 0-02) times maintenance requirements. The small changes observed in the physiological variables: heart rate, respiratory rate, packed cell volume, haemoglobin concentration and enzyme activity of creatine kinase, lactate dehydrogenase and aspartate amino transferase, showed that the horses were exercised under submaximal conditions. However, the significant increase in blood cortisol concentrations showed that horses experienced some degree of stress during ploughing work. The significant increase in blood triglycerides concentration observed after each period of work seems to demonstrate that fat mobilization is an important metabolic pathway as an energy supply for the working muscles during prolonged and low speed draught work.

Antioxidants status and physiological responses to early and late heat stress in two rabbit breeds

“…Blood triglycerides (TG) were higher in the rabbit groups that were subjected to early heat stress at 5 weeks of age ( p < 0.05) compared with the control groups. This could be due to the increased mobilisation of lipid reserves as a result of the high heat dissipation (Pérez et al, 1996). A similar drop in blood TG was seen when comparing those exposed to late heat stress to those exposed to early heat stress.…”

Walk and trot in the horse at driving: kinematic adaptation of its natural gaits

“…Much has been written during the last two decades on basic stride characteristics, such as temporal, linear and angular variables, in different gaits and sport situations by Galisteo et al [14,15], Clayton [9,10] and Miró et al [23], and on coordination of joints within the equine fore and hind limbs by Back et al [5,6]. Concerning draught horses, studies on physiological adaptation to ploughing work by Perez et al [24] and driving competitions by Snow [26] have been carried out. However, few data are available regarding the basic stride characteristics of driving horses.…”