Goat nutrition

Energy requirements of small ruminants

Energy is the main limiting factor to animal performance and survival. Metabolisable Energy (ME) requirements of your animals is dependent on the animal's level of production. The amount of energy available from a feed depends on its digestibility. 

Metabolisable energy is assessed as megajoules of metabolisable energy per kilogram of dry matter (MJME/kgDM). Dry Matter (DM) is the non-water component of a plant.

Digestibility will be given as a percentage. The higher the digestibility the more energy the goat will get from the feed as less is passed through as waste products. 

It can be difficult to accurately determine the intake and quality of the diet when goats are grazing native pastures. Read more about pasture quality. 

Digestibility is heavily influence by fibre content and balance of nutrients in the diet. For example, if a goat is on a high fibre diet, they can only consume approximately 1.5% of their body weight (BWT) but if they were on a low fibre, high concentrate diet they can consume 5% BWT.

Feeding goats grain or pellets

Fibre is recommended at 15% of the diet to maintain a healthy gut and prevent grain poisoning.

Introduction of grains or pellets into the diet to increase the energy or protein levels should be introduced slowly over 2 weeks to prevent upsetting the healthy gut bacteria. 

Watch for clinical signs of grain poisoning (acidosis). 

If goats are on a grain diet, it is recommended to have a limestone: salt (1:1) lick available or to mix 1% limestone and 0.5% salt into the grain mix. 

To prevent bladder stones (uroliths) when goats are on a grain or high concentrate diet, add 1% ammonium chloride to the diet. 

A buffer pellet is often used to prevent grain poisoning, but they need to ensure that it is palatable.

Tips when changing diet

• A Clostridial vaccination should be given when there is any change is diet, to prevent enterotoxaemia (commonly called ‘Pulpy Kidney’).
• Supplementary feed should not be fed off the ground, not only will it increase wastage but also increase chance of disease (bacterial infections)
• If you are mixing your own diets, check feed in the bin daily to see if they are sorting out feed with their mouths and leaving parts of the diet behind.
• Change in weather can alter the feed intake and when they bounce back can induce acidosis
• When supplementary feeding, ensure there is enough room for all goats to eat and are not being bullied. If so, they should be removed and fed separately.
• Clean water daily. When on a grain/concentrate diet, the feed will get a lot of grain dust/debris and the water will taste off. Decreased water consumption will decrease feed intake.

Over-feeding goats

Excessive ingestion of high energy feed results in rapid fermentation of carbohydrate in the feed and formation of large quantities of lactic acid.

The lactic acid decreases the pH of the rumen creating a ruminal acidosis. 

If the concentration overload has created a ruminal acidosis, then clinical signs include:

• reduced appetite
• lethargy
• abdominal pain
• colic symptoms
• subnormal temperature
• absent ruminal movement
• diarrhoea (loose faeces to a frank diarrhoea with undigested grains)
• death. 

In cases of mild-moderate overfeeding of concentrates, the goat may become mildly affected and sometimes spontaneously recover. Severe ruminal acidosis from over-feeding requires veterinary assistance.

Undigested feed passing into the small intestine can also lead to an overgrowth of Clostridium perfringens type D and consequently enterotoxaemia.

Goats that have been on a high concentrate diet for a long period will develop a chronic laminitis, where the feet have a relatively normal shape, but they are extremely hard to trim and have a thick platform sole. 

Ensuring a healthy diet

Pet goats can often be in a state of subacute-subclinical ruminal acidosis due to:

• low fibre intake
• overfeeding concentrate feeds
• feeding inappropriate feeds such as supermarket waste
• excessive amounts of supplements
• lack of exercise. 

It is important that all goats have long fibre in their ration. Long fibre stimulates eructation (burping), cud chewing and production of saliva. Saliva assists with buffering the rumen and maintain an ideal pH.

When increasing the concentrate feed in the diet of small ruminants it is important to increase in small increments over 2 weeks. This enables the rumen bacteria to adapt to the change in diet. 

Monitor carefully for any early signs of acidosis, such as decrease in appetite, reduced rumen movement and floppy faeces. If any of these signs are noticed, then immediately remove the concentrate diet.