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AQHA VET NEWS
2 . LOW STARCH , SUGAR AND NSC FEEDS : High starch / sugar feeds also increase the risk of stomach ulcers and gut acidosis – and hence colic , hoof problems and laminitis . Many pelleted and extruded feeds are based on grain by-products such as millrun , bran and pollard which are all high in starch and sugar . It is particularly important to avoid these feeds for pregnant mares and youngsters . Gastric ulcers occur in 60 % of crib-biting foals compared to 20 % of noncrib-biting foals and the incidence is reduced in youngsters on high fibre / oil enriched diets .
At around 28 weeks gestation , pregnant mares have a reduced ability to take up glucose from the blood - this ensures it is diverted to the growing foal , but also increases risk for laminitis in pregnant mares and developmental orthopaedic diseases ( DOD , OCD , bone cysts , bent legs ) in foals . DOD became a widespread problem after high starch / sugar creep
mares , foals and weanlings . Replacing such diets with high fibre / oil-enriched diets also affects temperament in weanlings and yearlings . Both before and for up to 10 months after weaning foals on a fibre-oil supplement show less stress .
Horses with recurrent exertional rhabdomyolysis and PSSM ( type 1 or 2 ) limiting starch / sugar intake underpins management and current recommendations are that less than 20 % of energy intake comes from sugar / starch and at least 20 % from oil . All grains and high starch / sugar feeds - including feeds containing grain by-products such as millrun , bran , pollard , hominy meal should be avoided and used with caution .
Micronised and extruded feeds : Although micronized and extruded feeds benefit horses needing high energy grains , their increased small intestinal starch digestion can cause problems for other horses . Heat processing can increase small intestinal enzyme activities by over 446 % profoundly increasing the damaging effects of starch and sugar-based feeds .
3 . PROTEIN QUALITY AND ESSENTIAL AMINO ACIDS : Are important for all horses regardless of discipline , work level or reproductive status , because they impact hoof strength and integrity , work capacity , body composition , power-to-weight ratio , endurance and reproduction . Muscle building is so specific that if the feed meets required levels of 9 essential amino acids , but has only half the tenth , body protein synthesis ( ie muscle , bone , red cells etc ) may be reduced by up to 50 %. A deficiency of any single essential amino acid places a limit on tissue building . Just as the shortest plank in a barrel limits the amount of water the barrel contains , an essential amino acid deficiency places a limit on new cell creation . feeds were introduced in the late 1960 ’ s . Ongoing studies into DOD have found genetics contributes approximately 25 % and environment 75 % - especially high starch / sugar feeds and rapid growth .
Most hock lesions are present at 1 month of age and there is evidence they can develop during gestation . Stifle lesions appear between 3 and 5 months of age and there is a positive correlation between OC and weight gain in the 3rd to 5th months . The risk continues through weanlings and until the yearling stage – making low starch / sugar diets important in
Once an essential amino acid runs out , the building of tissues that require that amino acid , stops and unusable amino acids are converted to fat . Lucerne , soy meal and whey protein are all ‘ good quality ’ because they are high in lysine , methionine , threonine , leucine-amino acids that build muscle , stamina , tendon strength , bone , red cells etc .
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