The browsing dromedary camel: I. Behaviour, plant preference and quality of forage selected

Abstract

A study was conducted in the Erer valley, Eastern Ethiopia to determine the behaviour, dietary preference and forage quality of free ranging dromedary camels. Each day for 24 days each in the dry and wet seasons, one camel was randomly selected from one of four age and sex categories (adult males (AM), young males (YM), young females (YF) and adult females (AF)), to measure time spent on various activities. The observation period was between the time of turning out for browsing and coming back to corrals at dusk. Browsing/grazing was the dominant daytime activity occupying between 0.63 and 0.68 of the time in both seasons, followed by walking, resting other activities and ruminating. Young camels spent more ( P < 0.01) time browsing than adults. The adult camels spent more ( P < 0.05) time resting and on other activities, as compared to the young camels in the wet season. Variation between seasons was also high and more ( P < 0.001) time was devoted to browsing in the dry season. In contrast, walking, ruminating and other activities were higher ( P < 0.001) in the wet season. Browsing preference, observations were made on 240 camels to measure time spent feeding on different plants. Each camel was followed for a maximum of 3 min in both the dry and the wet season. The camels selected a total of 21 species of plants in the dry and 30 in the wet season. On average, 0.79 and 0.83 of the camels’ diet was comprised of perennial woody plants in the dry and wet season, respectively and the 10 most preferred plant species occupied 0.87 and 0.80 of the total feeding time in the dry and the wet season, respectively. The highest ranked plant was Opuntia (0.18) in the dry season and Acacia brevispica (0.22) in the wet season. The range in composition of the ten most preferred species (g/kg dry matter (DM)) were for crude protein (CP) 88–228, P 1.3–3.3, Ca 12–48, soluble tannins 29–216 and condensed tannins 9.4–129 abs. unit/g. In vitro dry matter digestibility (IVDMD) varied between 0.41 and 0.65.