Time budgets of maintenance activities and dietary characteristics of camels (camelus dromedarius) and goats (capra hircus) in the semi-arid southeastern Kenya

Abstract

The grazing behaviour and dietary characteristics of camels and goats grazing together were studied on a 50 ha plot at Kibwezi Dryland Field station in southeastern Kenya.Tree and shrub densities of woody plants on the site were determined using the Point Centred Quarter Method (PCQ). The production of the herbaceous plants was quantified in dry and wet seasons by clipping all material within 0.25m2 quardrats, drying and weighing it. Grazing behaviour was determined using focal observation methods. Microhistological technique was used to determine the dietary botanical composition of camel and goat diets. Time spent feeding, walking, ruminating, resting and other activities was influenced by both advancing plant maturity which spanned three consecutive 16-day study periods and animal species. Camels spent less time feeding than goats. For both species, feeding took place mainly in the morning and late afternoon. At mid-day, the majority of animals rested or ruminated. Time spent walking was affected by advance in plant maturity in the case of camels alone. This increased from period one to three. The two animal species, however, spent the same time walking in the study. The distribution of walking over the observation day was similar to that of feeding. Ruminating time was not affected by advance in plant maturity for the two species. Camels ,however spent less time ruminating than goats. Animals spent more time resting while standing than when lying. Resting time decreased with advance in plant maturity for both species. Camels, however, spent more time resting than goats. Likewise time spent in other activities decreased with period. Camel and goat diets were composed primarily of browse in the dry and v wet seasons.Its contribution to camel diets was 90.16 % and 93.99 % in the dry and wet seasons, respectively. Its proportion in the goat diets was 77.30 % and 61.31 % in the dry and wet sesaons. Goats were more adept at switching from one forage class to another than camels. The order in which the camels and goats selected plants and their dietary overlap were influenced by season. Generally dry season plant samples were lower in crude protein (CP) than the wet season samples. The fibre and lignin content of dry season samples was higher than in the wet season samples. Consequently diets selected by camels and goats in the dry season were lower in quality than their wet season diets. Browse was of higher nutritional value than grass in both seasons as most browse species contained higher crude protein (CP), cell solubles (CS) and were more digestible than grass species. Overall, camels and goats met their nutritional requirements in both dry and wet seasons. However, they did not associate preference with nutritional variables of plants such as crude protein (CP), acid detergent fibre (ADF), and dry matter digestibility (DMD), especially in the dry season. These findings form a guideline for range managers in assessing the usefulness of the vegetation resource to camels and goats and how the two species exploit the resource.