Intake and digestibility studies with captive African lions (Panthera leo), leopards (Panthera pardus) and cheetahs ( Acinonyx jubatus)

English: The long-term goal of this study of the quantitative nutrition of large African predators was to develop non-invasive techniques for the accurate determination of food intake and apparent nutrient digestibility by free-ranging predators. The specific objectives of this study were to: • develop non-invasive techniques to determine the apparent digestibility of fresh, nonprocessed food by three species of large African predators. • determine the apparent dry matter (DM) digestibility of typical carnivorous diets in terms of DM, crude protein (CP), minerals, fat and gross energy (GE). • obtain information on the digestive capabilities and the water retention in three species of large African predators. • lay the basis for developing a technique to determine the food intake on a nutrient basis by free-ranging large African predators. This study was conducted in the Bloemfontein Zoological Gardens (Bloemfontein Zoo) with paired captive male and female African lions (Panthera leo), leopards (Panthera pardus) and cheetahs (Acinonyx jubatus). Although the study was done with captive animals the techniques were developed in such a manner that its principles would be applicable in the uncontrolled environment of free-ranging predators. The study consisted complete intake and digestibility trials conducted and repeated three times respectively 'on a male and a female of each of the three predator species. The trial diets consisted of portions' of the limbs from either adult donkeys (Equus asinus) or a horse (Equus cabal/us). The trial carcass portions used consisted of two symmetrical and identical portions or cuts that were divided in different sections, e.g. the two front limbs or the two hind limbs originating from the same carcass. One carcass portion was fed to a specific predator as the trial diet and the mirror image carcass portion was retained for nutrient analysis in the laboratory. The trail diets were marked using maize seeds (Zea mays) as external marker to assist in the faecal identification and facilitate collection. After feeding a ration, total faecal and food refusal collections were made. The intake and apparent digestibility of the fresh food, DM and nutrients were determined using standard laboratory techniques. The results of the intake and digestibility trials with the African lion, the leopard and the cheetah have shown that these carnivores are well adapted for the ingestion and digestion of meat. Mean DM intakes ranged from 0.970 kg for a female leopard to 4.493 kg for a male lion. The mean apparent DM digestibility ranged from 0.854 to 0.957. Nutrients such as CP, lipid and GE had very high apparent digestibility coefficients by the predators ranging from 0.919 to 0.977 for CP, 0.983 to 0.995 for lipid and 0.918 to 0.967 for GE respectively. The apparent digestibility of minerals (ash) was lower ranging from 0.310 to 0.853. From this analysis the conclusion could be made that there is no statistical difference between the lions, leopards and cheetahs in this study in terms of the apparent digestibility of fresh food, dry matter (DM), crude protein (CP), lipids, minerals and gross energy (GE). This study also confirmed that large African predators obtain a considerable amount of water from their diets. The use of apparent digestibility coefficients for fresh food and DM can be a very useful method to estimate the actual food intake (on a fresh or DM basis) of carnivores. If the information is available and the techniques described are applied judiciously, it might be possible to estimate the food and nutrient intake of large African predators. Evaluation of the nutritional status of large African predators during the different physiological stages of their lives in a non-invasive manner will thus be possible. It will also provide scientific support to devise adequate, sustainable and holistic management practices to preserve both the large African carnivores and the environment that supports their existence.