Elephants Elephants - Wildpro - Twycross Zoo

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Elephants MUST be provided with appropriate browse.
Fibre
The feeding of a diet with adequate fibre is essential for elephants to maintain
normal digestive function and to avoid colic. The elephant’s digestive tract
and teeth are adapted to a fibrous diet. Hay is the main source of fibre in
elephant diets, however the fibre content varies enormously depending on the
species, growing conditions and time of harvest of the grass. No analysis of
hay fed to elephants was provided from any of the zoos. In the absence of this
data, published values for sun dried British meadow hay (MAFF 1986), were
used.
Fibre is not a nutrient, hence there are no recommended levels published; all it
can do is provide energy, so digestibility needs to be taken into account and
all other nutrient concentrations designed relative to energy content. Fibre
has been expressed as crude fibre, acid detergent fibre (ADF), neutral
detergent fibre (NDF) and lignin. ADF represents the cellulose and lignin in
the feed – these are both indigestible compounds. ADF is used by nutritionists
to predict the energy value of the feed, forage maturity and the ability of a diet
to maintain normal rumen function. NDF includes cellulose, lignin and
hemicellulose and effectively represents the total fibre components of the diet.
The ADF and NDF values provide information for estimating digestibility and
maximum animal intake of fibre in the diet.
There are some values available for the fibre content of natural elephant
forage ranging from between 13-62% crude fibre, and the results of our
analysis fall within this range. It has been suggested that hays with an ADF of
over 30% should be fed to elephants to prevent colic, however this can only
possibly be determined if zoos analyse the hay they are feeding (Ullrey et al
1997).
Protein
The recommendation for protein content in elephant diets is 8-10% dry matter
(Dierenfeld 1994). Adequate protein is important in elephant diets, with
deficiency reported to cause illness and death in young elephants fed a diet
containing 5.5% protein (dry matter) (Ange et al 2001) (Ullrey et al 1985).
All the diets analysed contained protein levels higher than this
recommendation, the mean protein content being 13.6%, thus protein content
would therefore seem to be adequate. However, interpretation of these data
has to take into account that the hays fed to all the zoo elephants had not been
specifically analysed rather values were taken from standard feed tables. As
standard tables generally refer to high quality hay and the nutrient value of
hay varies according to the species and the stage of maturity at cut (amongst
other factors), protein requirements may not be fully met by feeding hay alone
without supplementation using a concentrated feed. Pregnant, lactating and
growing animals require a higher proportion of protein in their diet. Ullrey et
al (1997) suggest 10% for pregnant cows and 14% for late pregnancy and first
year of lactation, lowering to 12% for the second year of lactation.
Fat
The natural diet of elephants is low in fat (1.2-1.8%), (Dierenfeld 1994) (Spencer
1990) and captive elephant diets should be developed to replicate this to