Sheep are grazers and goats are intermediate feeders. By employing O2 consumption and heart rate measurements, resting metabolic rate (RMR) and field metabolic rate (FMR) were determined in four male fat-tailed Awassi sheep (44.0 ± 3.94) and four male Baladi goats (35.5 ± 5.42 kg) that were co-grazing natural pasture in the Negev Desert. There were 67.7 ± 3.75 g DM/m2 of herbaceous vegetation biomass, which was rapidly becoming senescent and more fibrous. We hypothesized that FMR of these desert-adapted ruminants would be relatively low when compared to other sheep and goat breeds, as animals in arid areas tend to have low metabolic rates. Both sheep (n = 6) and goats (n = 6) foraged 71% of the allotted 11 h free-pasture period; however, sheep grazed more than goats (P < 0.001); whereas goats browsed more than sheep (P < 0.001). RMR was higher (P = 0.007) in sheep than in goats (529 ± 23.5 v. 474 ± 25.4 kJ/kg0.75 BW/d), but FMR did not differ between species (618 ± 55.7 v. 613 ± 115.2 kJ/kg0.75 BW/d). In addition, the cost of activities, as a proportion of FMR, did not differ between sheep and goats; FMR increased by 89 kJ/kg0.75 BW/d or 17% in sheep and by 138 kJ/kg0.75 BW/d or 29% in goats. In comparing FMRs of sheep and goats in this study with these species in other studies, differences were inconsistent and, therefore, our hypothesis was not supported.

中文翻译：

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内盖夫贝都因人饲养的阿瓦西绵羊和巴拉迪山羊的静息和田间代谢率

绵羊是食草动物，山羊是中间饲养者。通过采用 O2在四只雄性肥尾 Awassi 羊 (44.0 ± 3.94) 和四只雄性中测定消耗和心率测量、静息代谢率 (RMR) 和野外代谢率 (FMR)巴拉迪在内盖夫沙漠共同放牧天然牧场的山羊 (35.5 ± 5.42 公斤)。有 67.7 ± 3.75 g DM/m2草本植物生物量迅速衰老和纤维化。我们假设与其他绵羊和山羊品种相比，这些适应沙漠的反刍动物的 FMR 相对较低，因为干旱地区的动物往往具有较低的代谢率。两只羊（n= 6) 和山羊 (n= 6) 在分配的 11 小时自由放牧期间的 71% 中觅食；然而，绵羊比山羊吃草更多（磷< 0.001); 而山羊比绵羊浏览更多（磷< 0.001)。RMR 更高（磷= 0.007) 绵羊比山羊 (529 ± 23.5)五。474 ± 25.4 千焦/公斤0.75BW/d），但 FMR 在物种之间没有差异（618 ± 55.7五。613±115.2千焦/公斤0.75体重/天）。此外，作为 FMR 比例的活动成本在绵羊和山羊之间没有差异；FMR 增加 89 kJ/kg0.75BW/d 或 17% 绵羊和 138 kJ/kg0.75BW/d 或山羊的 29%。在将本研究中绵羊和山羊的 FMR 与其他研究中的这些物种进行比较时，差异不一致，因此，我们的假设不被支持。