Seasonal Composition of the Diet of the Free-Roaming Equines in Northern Coahuila, México

Abstract

Donkeys and horses are large non-ruminant herbivores found worldwide. They are part of the cultural heritage of many countries and also make use of natural resources when grazing freely. In Mexico, the potential or current impacts these animals may have on natural habitats shared with wildlife and other domestic animals have been scarcely documented. The objective of this study was to evaluate ecological variables of their diet, identify preferred plants, and generate information to support management decisions. The study was conducted in northern Coahuila, where diet content was analyzed through fecal microhistology during spring and summer. A total of 43 plant species were identified in the diet, with biodiversity values ranging from 2.12 to 2.34. Botanical composition varied between seasons, showing less than 60% similarity. The most frequently occurring species included Opuntia macrocentra, grasses such as Cynodon dactylon, Erioneuron pulchellum, Bouteloua gracilis, and B. curtipendula, as well as Aloysia wrightii among non-grass herbaceous plants. Grasses made up the majority of the diet in spring, while herbaceous plants were dominant in summer. This information provides a reference point for rangeland management in northern Coahuila, where cattle ranching is increasingly challenging. Diversifying land use and balancing it with the habitat needs of wildlife should be taken into account.