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GUARDIAN FARMING
Is there enough fibre in green grass?
Jenny Paterson, B.Sc
Does Green, Growing Grass Supply Enough Fibre For Our Horses? Unfortunately not! This is because of its stage of growth. Mature grass, like roadside grass, or grass when it is about to be baled for hay, contains way more fibre than the short, green growing grass our New Zealand horses are averagely eating. Constant grazing keeps grass in this young non-fibrous stage of growth (a bit like your lawn!). Grass is made up of two types of carbohydrate: 1. Structural. This is the cell walls (cellulose), the fibre part. It is the bricks and mortar of the grass, in other words it is what makes the grass ‘stalky’. Young green, growing grass is not very ‘stalky’
Short green, growing grass, higher in non-structural carbs (sugar), protein and potassium.
2. Non-Structural. This is the soluble carbohydrate which is found inside the cell walls, the ‘juice’ if you like, or the ‘sugary’ part. Horses need to be supplied with a diet high in structural fibre because their whole digestive system is geared for it. Their exceptionally strong stomach acids start the break-down process of this coarse material which is eventually completed by the billions of resident micro-flora waiting in their huge hind-gut. These micro-organisms simply cannot digest the excess carbohydrate dumped on them when the diet is high in green grass and molassed grains. Instead, this excess sugar ferments, resulting in acidosis which kills off the ‘good flora’. There ensues a chain reaction of metabolic chaos within the horse. You might notice green, soft or sloppy manure, behavioural problems, maybe sore feet. Like us you probably have taken these issues lightly in the past. However, we have now become aware that these symptoms can represent early signs of more serious trouble brewing. Green, growing grass is comparatively high in nonstructural carbohydrates (or sugars) and low in fibre. Some grasses are much higher in sugars than others, like your rye/clovers which are selected to achieve rapid weight gain and milk production in livestock. Not what we are after for our horses! Here are some comparisons of the NSC content of various grasses and grains (from Dairy One, USA) Rye-Grass up to 39% Weeds 27% Cocksfoot 20% Red Clover 18% Brown Top 10%
Mature brown-top, high in structural carbs (fibre) and comparatively low in sugar. Grass Hay Oat Hay Straw Beet Pulp Corn Barley Oats Molasses
13% 23% 12% 12% 73% 63% 50% 58%
It is important to work out the total NSC (sugar) content of your horse’s diet. If he is eating predominantly green, growing grass, especially if it is a rye/clover mix AND you are feeding molassed grains, then he is probably suffering the carbohydrate overload mentioned, causing ‘Metabolic Syndrome’, insulin resistance, and in some cases, obesity and laminitis. Too much sugar, not enough fibre! This is in addition to the other problems you will likely be experiencing from the imbalances of excess potassium/ nitrates: inadequate sodium/calcium/magnesium, mycotoxins, and photodynamic pigments also associated with these kinds of grasses. Rye-grass represents even more trouble because when night-time temperatures become too cool for growth, it stores its sugars as fructans. Whereas horses can process starch, they do not have the ability to digest fructans. The streptococcus bacteria, normally present in small numbers in the hind-gut, has a population explosion when fructans arrive, causing upset to the beneficial intestinal flora and inflammation and damage to the lining of the gut and potentially triggering laminitis.
The key is to think in terms of supplementing fibre to feed the flora in the hind-gut which in turn feed the horse, keeping him calm and healthy. A person would do well to think of every possible way to add fibre to his horse’s daily diet. Horses require approximately 2% of their body weight in coarse fibrous material every day, not just when ‘you run out of grass’! This can come from as mature grass as possible, good quality hay, beet products, and hay chaffs. (Baleage is fine so long as it has been stored properly). Remember to avoid rye/clover mixes as mycotoxins are still present in hay made from these grasses. Brown top, cocksfoot, crested dog’s tail and Yorkshire fog or any mixtures thereof make fabulous high fibre, low sugar forages for recreational horses. Add any of the Bromes like Prairie grass and some Timothy for breeding or performance horses. Young, green, growing grass, grains and pellets race thru the horse’s system in 24-36 hours, whereas fibrous foods like hay take more like 50-60 hours. Because fibre takes more time to chew and pass through the horse, their whole system slows down and they become contented and healthy. They no longer have a pathological hunger for sweet grasses and cease gutsing and gorging! The difference in ‘temperament’ is amazing. Feedback from people who have made the effort to reduce or eliminate these harmful grasses, and increase the fibre content of their horse’s diet with more hay, beets and hay chaff, is truly inspiring. We are kind of programmed to prefer the ‘green’ look of our paddocks. Unfortunately the ‘green’ look means potential health and behaviour problems especially at certain times of the year and weather conditions. The ‘brown’ look is much more conducive to producing calm, healthy horses that you can enjoy.
120 High Street, Southbridge, Canterbury, New Zealand Ph: 03 324 2571 www.drilling.co.nz IRRIGATION & DOMESTIC WELLS, AQUIFER TESTING, ELECTRONIC WELL MONITORING, WATER QUALITY TESTING