Study methods and procedures for ungulate food habits
有蹄类食性研究方法及研究进展

The diet composition of Ungulates can be examined in a variety of ways: direct observation of the animals, utilization method, analysis of the rumen content, fecal analysis or fecal DNA analysis. All methods are likely to yield some valuable information, but they also each have their theoretical and practical benefits and drawbacks. Direct observation of the animals is a simple and inexpensive method to determine which plants are important in the diet composition, but it is difficult with shy animals or in unsurveyable terrain, without the use of special equipment. The utilization method provides little disturbance for the animals, but it is difficult to distinguish between related species. Furthermore, feeding traces can not be recognized for all plants and they quickly disappear during the growing season. Before the 1970 s, analysis of rumen contents was the most common method for studying food habits. However, this method requires a good knowledge of plant morphology and anatomy in order to recognize different plant species in the rumen content. Because the same population of herbivores can be continuously sampled without direct interference and no animals need to be killed, the fecal analysis method is regarded as the only way that the food habits of protected animals can be examined. Basically, this method is used to quantify the proportions of different epidermal fragments in faeces, count the number of fragments, and estimate or measure the surface areas of fragments. Fecal DNA analysis is a new technique in presently which animal DNA is extracted from the feces. The technique is presently used to determine food habits.