Download Native Ponies – Nutrition by Nick Canning, East Coast Viners Native

Native Ponies – Nutrition by Nick Canning, East Coast Viners
Native ponies have undergone the process of evolution to allow them to adapt so as to be
able to utilize poor grazing and harsh environments. The basis of any ponies’ diet should be
fibre. Native ponies can spend up to 70% of their days foraging.
The digestive tract starts with the mouth. This has two main functions- To masticate food
and wet food with saliva. The jaw will sweep on average 60,000 times/day when grazing.
The feeding of concentrates uses a shorter jaw sweep than forages which can then lead to
the uneven wearing of teeth. The animal will select the pieces of forage using the lips to pick
up grains. The incisors, located at the front of the mouth rip the forage and the food is then
ground up by the premolars and molars before swallowing can occur. The stomach can hold
between 9-15 litres and is a very important part of the trickle feeding system. It is quite small
for the animals’ size and works best when it is about half full. This means that once the
stomach begins 2/3rds full it will start to empty even if the food is not digested/processed.
Small feeds or regular foraging is the most efficient way of feeding the horse. The small
intestine makes up 30% of the digestive tract and contains approximately 40-50 litres. Starch
digestion occurs within the stomach and small intestine. The small intestine is the site of
amino acid and fat digestion/absorption. Vitamins and minerals are also absorbed here. The
large intestine starts with the Caecum. This is a pouch within the system that takes the
cellulose plant fibre and then ferments it for a further 6-8 hours. The microbes in here are
responsible for producing vitamin K, B-complex vitamins, proteins and fatty acids. This
fermented product then passes to the large colon. This can be where twisted gut occurs due
to the series of pouches become twisted and fill with gas. The next step is into the small
colon. The Job of the small colon is to recapture any excess water. Faecal balls are then
produced, passed to the rectum and expelled. By mimicking the natural feeding habits of the
pony will minimise the risk of digestive upsets.
The hindgut generates enough heat by digesting fibre to keep most unclipped native ponies
warm during the winter months. The heat produced by a pony eating 1kg of hay is twice the
amount produced by eating 1kg of barley.
Water makes up between 60-70% of a ponies body weight. A severely dehydrated pony may
have only lost 8-10% of their natural body water however this is dangerous. Forages and
feed are mixed with saliva in the mouth to produce a moist bolus which is easily swallowed.
This amounts to approximately 35 litres of saliva production per day.
Starch is an important and valuable part of the diet. It is needed for efficient energy use,
helps produce healthy foals and is also required for milk production. The starch that isn’t
digested in the small intestine is delivered onto the hindgut for bacterial fermentation. Too
much starch may cause a big change to the hindgut flora, may increase volatile fatty acid
and lactic acid concentrations. Starch is made up of non-structural carbohydrates which are
broken down by the horse in the small intestine to provide energy. This is generally fast
release energy which provides a sudden burst of energy and is essential for horses working
hard however this can also cause excitable behaviour. Starch is a slow release form can
prevent fizzy/heating up behaviour.
Protein is needed for muscle + Bone Growth, Milk production, foetal growth and normal
metabolism.
The digestible energy (DE) is the energy level of the feed after digestion and therefore the
energy available to the horse for maintenance and exercise.
The nutritional quality of fibre can vary massively. Late cut hays and haylages tend to be
lower in sugar which can be useful for watching the weight on ponies. The soaking of hay for
a few hours will remove any soluble sugars but it will still provide a good supply of fibre for
the digestive system. Due to the nature of the trickle feed system it is very important that the
pony doesn’t go longer than 8 hours without food so therefore daily forage allowance should
be divided up over the day to keep the system working. The quality of grass can also vary
enormously, the grass in spring tends to be higher in sugars and therefore intakes for good
doers must be monitored closely. Depending on the quality and quantity of grass the pony
can quite easily survive on grass alone however it is highly likely the diets are lacking in
vitamins and minerals. Within the wild the horses would be constantly changing pastures
and eating a variance of feeds. This, in the wild would give a variant supply of minerals and
vitamins. Within a fixed pasture feeding system deficiencies can occur easily which should
be balanced up by a mineral supplement/grazing balancer. Oat straw can be used to mix in
with feeds as this will lower the energy density of the ration but also supply the bulk required
to keep the digestive system working.
Regular condition scoring, weighing and weigh taping will help to monitor changes in the
horses’ weight. It is the weight change in the pony which will indicate if the diet fed is
higher/lower in energy than the pony’s requirements.
As well as balancing the minerals it is also very important to balance up the sodium and
chloride levels. This is done easiest by feeding free-access salt.
Feeding hay or haylage? The main principle for conserving forage (grass) for future
feeding is to reduce moisture content and/or oxygen to stop natural decay that normally
begins once the grass is mown in the field. When making hay the water content of the crop
must be reduced from 60%-80% to 20% or less in 3-5 days. This can either be done by the
sun drying the crop in the field or by air/heat drying in a barn. Hay is the most traditional
method of conserving grass. It can however vary greatly in nutritional content. Hay is mainly
divided into meadow hay and seed hay. Meadow hay contains a large variety of different
grass and herb species. The different species mean that they will be at different stages of
maturation when the forage is cut. This results in more leaf and seed heads and is normally
less stalky and softer to touch. Seed hay is now thought to be single species grass hay such
as ryegrass or timothy. This is usually stalkier and less leafy so feels rougher in the hand.
On average seed hay is lower in protein than meadow hay. Dust in hay can come from
various sources such as: moulds and fungi can grow on the hay once cut prior to bailing in
damp weather conditions. If the forage is baled wet then this can lead to an increase in
temperature within the bales. This then produces a more suitable environment for moulds
and fungi spores to multiply. If the hay is very dry then the leaves can become very brittle
meaning the leaves can shatter during bailing producing a dust within the bail. Within difficult
years such as this the forage can become soil contaminated. This can be due to heavy rain
causing soil to splash on the forage. If the ground is damp and not firm then as the tedder
comes along the ground gathering forage it can actually sink. The hooked arms which
usually gather the forage into a line sit a little lower meaning they can hook the soil as well
as the forage thus collecting soil in the bout.
Haylage is wilted to a water content of 45-50% before being wrapped. This then allows
pickling of the crop in an oxygen free environment. As we learn more about feeding then
haylages cut later in the season are more suitable for feeding ponies. The trade-off with
forage is that at the start of the season the quality is at its highest with lower bulk however as
the season progresses the nutritional quality diminishes however the bulk increases. Once
the forage has been bailed a fermentation process then takes place and acidity increases.
This then drops the pH to approximately 5.0. This is a suitable pH to prevent moulds and
fungus growing. The forage is then stable providing no oxygen is introduced into the forage.
The whole ensiling process can take between 6-8 weeks. If the grass is ensiled when it is
too dry then it doesn’t contain enough soluble sugars. The sugars are needed by the acidproducing bacteria to adjust the pH. Insufficient sugar levels mean incomplete fermentation
so the pH doesn’t drop as far as it should and therefore moulds and fungus are able to grow.
Incomplete/secondary fermentation can definitely be a hazard to horses and can result in the
production of ammonia within the forage which can upset the horse’s airways.
Forage can be analysed supplying the dry matter, protein and ME. These figures can then
be substituted into the formulas in the presentation to calculate forage quantity requirements.