Nutrition

• The lateral movement of the jaws are not pronounced during mastication in elephants. This along with the lesser volume of the buccal cavity leads to poor digestibility and hence continuous feeding in wild elephants.
• Elephants graze and browse on the most tender and palatable portions of different plants and trees.
• Elephants spend between 12-18 hours feeding each day. They spend lesser time in savannah woodland and deciduous forest, compared to rainforest, due to the abundance of perennial grasses.
• The elephant feeds on leaves, bark, stem, twigs, pith, root, fruits and flowers.
• The number of plant species consumed generally exceeds 50 species in dry habitats, more than 100 in deciduous forests and over 200 in rainforest.
• Family Graminae (grasses including bamboo), Cyperaceae (sedges), Palmae (palms), Leguminosae (legumes), Combertaceae (Combertum family), Euphorbiaceae (spurges), Moraceae (figs), Anacardiaceae (Cashew family), Rhamnaceae (buckthorns) and the order Malvales contribute to the bulk of the elephant’s diet.
• Grasses and legumes are more important in drier habitats, while palms, vines and a variety of fruits are commonly consumed in moist forests.

Water

Apart from pure metabolic requirements, elephants need water for their natural functions like spraying on the body as well as for wallowing, for body temperature regulation since the elephant hardly sweats. It is estimated that an average sized adult Asian elephant loses 40 litres of water through urine and 20 litres through the lungs and skin. On an average elephants require a minimum of 150-200 litres of water each day
 

Protein

Proteins are polypeptides of amino acids required for building of body tissues. Several amino acids are not synthesised by mammals on their own and have to be supplied in the diet as essential amino acids. Among herbivores, only ruminants can synthesise several amino acids with the help of symbiotic microbes in the rumen. However, elephant being a non-ruminant herbivore, both qualitative and quantitative presence of protein in the diet is important in its nutrition.

Studies on Asian elephants in the wild in southern India showed the browse intake during the wet season had a crude protein content of 13-20%. During the dry season the crude protein was 6-18%. Grasses showed correspondingly lower value values of crude protein both during the wet and dry seasons.
 

Fibre

Elephants digest crude fibre with the help of microbes present in the hind gut, as is the case in other non-ruminant herbivores like horses. The elephant’s digestive system and teeth are adapted to a diet high in fibre content. The elephant being a continuous feeder with its large digestive tract, takes feeds low in energy but high in bulk. Both browse and grass are rich in fibre.
 

Fat

The natural diet of elephants is low in fat, found to be 1.2-1.8 % of the dry matter intake.
 

Minerals

Not much is known about the requirements for various minerals and vitamins in elephants. The tendency of wild elephants to feed on the bark of certain trees suggested that this might be a source for some minerals. Estimate of Ca requirement for Asian elephants is put at 60 g per day (Sukumar 1989). Ca concentration is generally high in legumes and low in grasses, while both P and Na are low in both legumes and grasses. At least 8-9 g of calcium is required for the proper growth of the tusks (Mc Cullagh 1969).

The deficiency of certain minerals in the elephants leads to Reproductive problems, Poor growth, Emaciation and Listlessness, Affects growth, reproduction and lactation, leads to Abnormal growth, poor appetite, Zn abnormality, Anaemia, emaciation, pale mucus membrane and irregular pulse.
 

Vitamins

Vitamins are a group of organic compounds essential for normal maintenance, growth and reproductive functions apart from protein, fat, carbohydrates and minerals. Many herbivores synthesise most, if not all their requirement of B complex vitamins.