Indexes of pasturable ecology of Equus ferus przewalskii (Equidae) in steppes of the Western Manych Valley (south-east of the Rostov Region, Russia)

Abstract

In 2015–2016, we studied the species composition, above-ground phytomass and feeding habits of semi-free Przewalski's horses (Equus ferus przewalskii) in a natural pasture of the steppe valley of the Western Manych. The above-ground mass of plants on the pasture varied within 146.0–168.9 g/m2. We determined the composition of plants consumed by Przewalski's horses and their proportion in diets using a method of microscopically analysis of faeces. Cereals (Poaceae) and sedges (Cyperaceae) (80 to 100%) were the basis of the diet of the Przewalski's horse in the snow-free period. The value of the herb use varied between 0.8% and 20.5%. The main fodder plants for Przewalski horses on this pasture were the following: Festuca valesiaca, Stipa spp., Bromopsis inermis, Agropyron spp., Carex stenophylla, Kochia prostrata, while Elytrigia repens, Poa bulbosa, Chenopodium spp. were eaten in a small amount. We estimated the nutritive value of forage vegetation and nutrition indicators (daily consumption, the feed digestibility). The feed digestibility was determined by the ratio of inert (indigestible) component (silicon) in the diet and faeces. We calculated the amount of consumed feed from the mass of selected faeces and feed digestibility. A semi-free Przewalski's horse consumed 4.7 kg to 10.7–11.8 kg (dry weight) per day. The maximum intake (11.8 kg/animal per day) was observed in autumn. Feed digestibility of forages by Przewalski's horses in the snow-free period varied between 53% and 62% (average was 56%).

Keywords

• above-ground phytomass
• daily feed intake
• diet composition
• feed digestibility
• feeding ecology
• food selectivity
• semi-free Przewalski's horse