Feeding Broodmares: Getting nutrition right without spending more than you need

Feeding Broodmares: Getting nutrition right without spending more than you need

Dr Nerida Richards

Excellent broodmare nutrition is a vital piece of the puzzle when it comes to producing sound, well grown weanlings and yearlings. Underfeed your broodmares and mare fertility and immunity plus the health and soundness of your foals will suffer. Overfeed your mares and you risk obesity related health problems, not to mention the fact that you are probably spending a lot more than you need to on feed. In the thoroughbred industry today where buyers are spending less and only buying the best, feeding economically and producing sound foals with clean radiographs is becoming more of a priority than ever. Can it be done? Yes, with some good management. Here are some tips that will help.

Condition score your mares

Body condition scoring tells you how much fat your mares are carrying and knowing how much fat your mares are carrying tells you whether you need to feed more or if you could get away with feeding less. To body condition score mares you have to feel parts of the body where only fat accumulates. I find the most useful areas to condition score mares are the top of the neck midway between the poll and the wither and over the ribs.

Pregnant mares in their last trimester should be maintained as close to a condition score of 6 (on the Henneke scale of 1 – 9) as possible. Any lighter than this and you may have issues with fertility, colostrum quality and milk production. Heavier than this and your mares will be experiencing increased wear and tear on their joints and where mares are obese you may see a higher incidence of angular limb deformities, reduced milk production and issues with fertility. Overweight mares are also an indication that you are overfeeding and spending more on feed than you need to.

Knowing your mares’ score

A mare in condition score 5 will look lighter in condition, there will be little to no fat on her neck, so when you pinch up the skin where the mane grows the skin will roll around easily in your fingers and over the top of the neck. You won’t feel spongy fat. You shouldn’t be able to see the ribs of mares in this condition when they are standing still, but if you run your hand over their ribs you will be able to feel the ribs very easily with just a light pressure. Mares in this body condition need extra feed coming into the time they will be foaling.

A mare in condition score 6 will have some fat filling in her neck, so when you pinch up the skin on the top of the neck there will be some soft fat between your fingers. The ribs should also have a soft covering of fat but with moderate pressure you should be able to still feel them quite easily. Mares in this condition should be fed to maintain their condition coming into foaling.

A mare in condition score 7 will look heavy in condition. She will be well rounded and may be starting to display a bit of a cresty appearance over the neck. When you pinch the skin on the top of her neck it will feel firm as there will be quite a lot of fat accumulated there. If you run your hand over the ribs they will be difficult to feel even with firm pressure. Mares in this condition need to have their feed closely managed to ensure they don’t get any heavier in condition prior to foaling.

It is really important to condition score mares with your hands. Mares, especially in the last trimester of pregnancy look deceptively fat, but on closer assessment you may find they are in good or even light condition. Important point here is don’t just use your eyes to assess your pregnant mares’ body condition; it really is a hands on job.

When adjusting calories, be mindful of minerals

When increasing or decreasing feed intake to control body condition you always need to be careful that you don’t over or underfeed minerals that are important for hoof quality, fertility and immune function in the mare and immune function, bone and joint development in the foal. All complete feeds will have a recommended feeding rate for pregnant mares ( generally around 3 kg/day) which is based on the amount of feed needed to meet a horse’s mineral and vitamin requirements.

If you find the recommended feeding rate for the feed you use is too high for your mares and would cause them to become overweight you will need to reduce the amount you feed. However, doing this may mean you will no longer be meeting mineral requirements. If you do reduce the amount of a feed below its recommended daily feeding amount you will need to add extra minerals to the diet to fill in the gaps. As an example, a 550 kg mare in her last trimester of pregnancy requires 190 mg of copper per day. If you feed 3 kg/day of a broodmare feed containing 54 mg/kg of copper and she gets 35 mg of copper from pasture or hay, her daily requirement will be met with a total of 197 mg of copper in the total diet. If however this mare was getting fat and you reduce the amount of broodmare feed to just 1.5 kg/day she would only be getting 123 mg of copper per day (81 mg from the feed and 42 mg from the pasture – the contribution from pasture is slightly higher as pasture intake would increase when hard feed amounts are reduced). This leaves a gap of 67 mg to be filled.

The easiest way to add additional minerals to the diet is to use a mineral balancer pellet. Mineral balancer pellets are highly concentrated so they contain a lot of minerals in a very small amount of feed, allowing you to meet mineral requirements without feeding unwanted calories. If your mares have access to very high quality pasture you may find that a mineral balancer pellet is all your mares need.

Utilise your pasture

Pasture is a valuable resource when it comes to feeding broodmares and can supply a large portion of a mare’s daily requirement for energy, protein, vitamins and some minerals. Making best use of it means your feeding program for your mares will be as economical as possible. They key to making sure mares utilise any pasture that is available is not feeding them too much. Mares that are too well fed will tend to laze around and use pasture as something to sleep on rather than something to eat.

If you have decent quality pasture that is in abundant supply, be mindful not to overfeed your mares. You should notice them out grazing for a significant amount of time. If you notice your mares don’t seem to graze much try reducing the amount of hard feed they are getting (being careful as discussed above to always balance your minerals). When you reduce the amount you are hand feeding them they should naturally be hungrier and head out to graze more. Reduce the amount of feed you are feeding until you find the point where if you go any lower your mares would lose weight. Feeding like this means you won’t feed more than you have to and you will be making best use of your most economical feed available – pasture!

If your mares do rely heavily on pasture I highly recommend having your pastures tested so that you can identify and correct any mineral imbalances that are all too often present in improved pastures.

Balancing act

Feeding mares represents a significant expense to a breeding operation. Mare nutrition also plays a major role in determining the quality and soundness of your foal crop. Feeding programs for mares need to be closely managed to ensure you aren’t overfeeding and spending more than you have to while still meeting all of a pregnant mare’s requirements. This can be done by condition scoring mares, adjusting feed rates accordingly and making best use of your pastures.

While cost of feed is an important consideration, don’t compromise the nutrition of your mares for the sake of saving some cash. You only need to have one or two foals with nutrition induced OCD and that will cost you more in surgery, recovery and lost sales revenue than it would have to feed your mares correctly in the first place.

To make feeding the late pregnant mare simple, Pryde’s EasiFeed have developed the ‘sliding scale’ feeding system that allows you to feed your mares to meet mineral and vitamin requirements without causing them to become overweight. The ‘sliding scale’ feeding system uses the Pryde’s 150 Pellet (a concentrated mineral balancer pellet) and BioMare Cubes together at varying rates depending on pasture quality and the mares need to gain or simply maintain body condition. The sliding scale for late pregnant mares is below:

Pryde's 150 Pellet (g/day)
Prydes BioMare Cubes (kg/day)
Pasture and/or hay
Pasture quality high
Diet 1
Free Access
Maintain body condition
Diet 2
Free Access
Diet 3
Free Access
Pasture quality low
Diet 4
Free Access
Increase or maintain condition
Diet 5
Free Access

For an assessment of your late pregnant mare diets, a mineral analysis of your mare pastures or to discuss your needs, contact Pryde’s EasiFeed on 1300 732 267 or email info@prydes.com.au.