Utilization of oxidizable substrates by the sheep hind limb: Effects of starvation and exercise

Effects of Exercise and Plane of Nutrition on Nutrient Utilization by the Hind Limb of the Sheep

“…It is convenient to do this in terms of total energy expenditure because, although whole-animal heat production was not measured in any of these experiments, the metabolic response to a given level of exercise can readily be calculated from the equations established by Clapperton (1964), based on the speed and gradient of walking. Calculations show that the level of exercise to which sheep were subjected in the present study was very similar to the less strenuous of the two levels used by both Jarrett et al (1976) and Brockman (1979), and tothe single level used by Judson et al (1976). Levels of feeding were also roughly comparable in all these experiments, except that the sheep of Jarrett et al (1976) had not been fed for 20 h at the time of experiment, so that resting levels of heat production were probably also similar.…”

“…Effects of exercise on nutrient utilization in sheep have previously been studied by Jarrett et al (1976), Judson et al (1976) and Brockman (1979). Before comparing our results with theirs, the different levels of exercise employed in this and other studies must be considered.…”

“…These results were not entirely supported by other observations from the same laboratory (Judson et al 1976), which showed little change during exercise in either the irreversible loss or oxidation of acetate in the whole animal. However, the sheep used by Jarrett et al (1976), although described as 'fed', had not been fed for 20 h at the time of experiment, when ruminal production of acetate must have been reduced, whereas those used by Judson et al (1976) were fed semicontinuously throughout the experimental period.…”

Post-Heparin Triacylglycerol Lipases in Ovine Plasma

“…of seven sheep) prior to heparin treatment was similar to those values previously reported (Annison 1963;Aulie et al 1971;Jarrett et al 1976) and accounts for about 60/0 of the total plasma lipids (Nelson 1973). Ruminants have significantly higher plasma FFA concentrations than have humans, and it has been suggested that this might reflect a different intestinal absorption pathway favouring FFA rather than TAG (Simmonds 1972).…”

“…1). Restricted feeding of sheep resulted in a much higher basal level of plasma FFA (::::.1·7 t-tmol ml-I ), which is comparable to that observed in fasted sheep by others (Jarrett et al 1976). Treatment of the diet-restricted sheep with heparin also produced a sharp increase in plasma FFA, of magnitude similar to that of sheep fed ad libitum, but the FFA concentration fell rapidly to near pre-injection level within 20 min.…”