34 research outputs found
Feeding Ecology of Asiatic Wild Ass \u3ci\u3eEquus hemionus\u3c/i\u3e
The Mongolian wild ass or khulan (Equus hemionus) is a potential competitor for forage to reintroduced Przewalski’s horses. To evaluate the major foraging plants of khulan we chose the alkane method that was first described by Mayes in 1984. Different plant species contain varying amounts and proportions of n-alkanes. This fact allows the determination of diet composition by comparing the plant alkane to the fecal alkane pattern. The major advantage is that the method is non-invasive and has been shown to be a reliable method in captive trials. Fecal and plant samples were collected simultaneously and preserved by drying. The alkane content was determined gas chromatographically after chemical extraction. The diet composition was calculated according to Dove and Moore (1995). The results showed that in autumn 2003 beside some grass like species herbs like Allium mongolicum and Zygophyllum pterocarpum were the major foraging pants in Gobi B Strictly Protected Area in southwestern Mongolia
Feeding Ecology of Asiatic Wild Ass \u3ci\u3eEquus hemionus\u3c/i\u3e
The Mongolian wild ass or khulan (Equus hemionus) is a potential competitor for forage to reintroduced Przewalski’s horses. To evaluate the major foraging plants of khulan we chose the alkane method that was first described by Mayes in 1984. Different plant species contain varying amounts and proportions of n-alkanes. This fact allows the determination of diet composition by comparing the plant alkane to the fecal alkane pattern. The major advantage is that the method is non-invasive and has been shown to be a reliable method in captive trials. Fecal and plant samples were collected simultaneously and preserved by drying. The alkane content was determined gas chromatographically after chemical extraction. The diet composition was calculated according to Dove and Moore (1995). The results showed that in autumn 2003 beside some grass like species herbs like Allium mongolicum and Zygophyllum pterocarpum were the major foraging pants in Gobi B Strictly Protected Area in southwestern Mongolia
Running Speed in Mammals Increases with Muscle n-6 Polyunsaturated Fatty Acid Content
Polyunsaturated fatty acids (PUFAs) are important dietary components that mammals cannot synthesize de novo. Beneficial effects of PUFAs, in particular of the n-3 class, for certain aspects of animal and human health (e.g., cardiovascular function) are well known. Several observations suggest, however, that PUFAs may also affect the performance of skeletal muscles in vertebrates. For instance, it has been shown that experimentally n-6 PUFA-enriched diets increase the maximum swimming speed in salmon. Also, we recently found that the proportion of PUFAs in the muscle phospholipids of an extremely fast runner, the brown hare (Lepus europaeus), are very high compared to other mammals. Therefore, we predicted that locomotor performance, namely running speed, should be associated with differences in muscle fatty acid profiles. To test this hypothesis, we determined phospholipid fatty acid profiles in skeletal muscles of 36 mammalian species ranging from shrews to elephants. We found that there is indeed a general positive, surprisingly strong relation between the n-6 PUFAs content in muscle phospholipids and maximum running speed of mammals. This finding suggests that muscle fatty acid composition directly affects a highly fitness-relevant trait, which may be decisive for the ability of animals to escape from predators or catch prey