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HORSE HEALTH: FEEDING FOR BREEDING
with poor winter pastures – and pregnant mares need more nutrients.
The primary need is protein and minerals – not energy. Energy requirements increase with lactation, not so much during pregnancy. All care must be taken to ensure the feed is low in starch and sugar and mares don’ t become overweight. It’ s important to keep in mind that pregnant mares in lean or normal body condition can become insulin resistant on feeds high in starch.
Studies in quarter horses have shown that even in normal, non-pregnant, healthy horses, starch and sugar are associated with insulin resistance, obesity and laminitis.
Because mismanagement of pregnant mare nutrition has profound health effects for the mare and the foal, it’ s important to avoid mistakes. Reading labels carefully( Table 2.) and feeding a diet based on roughage with added oil( 250 – 500ml / day) and a balancer more closely mimics the natural grazing state of pasture and allows for adaptation of glucose and insulin levels to pregnancy and lactation.
Low starch / sugar feeds combined with high roughage, oil-enriched diets have little effect on insulin and have been shown to protect against the development of laminitis in mares and DOD in foals.
TABLE 2. FEED LABELS: READING BETWEEN THE LINES- WORDS CAN BE MISLEADING READING BETWEEN THE LINES
' Cool feed ' implies the feed has been formulated to avoid spikes of rapid energy- unless blood glucose levels have been measured after feeding, this term is misleading- contact the manufacturer for research carried out on the‘ cool’ feed.
' Grain-free ' generally means no whole grains but these feeds are commonly based on, or contain grain by-products which are called‘ cereal co-products’, bran, pollard, millrun, mill mix, hominy meal – all of which are high in starch and sugar
' Whole grain-free ' the feed may contain cracked, rolled, crushed or processed grains- all of which are high in starch and sugar
If the label doesn’ t list % starch and % sugar or % NSC, it may be unsafe. ' Low starch ' both starch and sugar increase blood insulin, so even if a feed is labelled low starch, it may be high in sugar
' Low sugar ' both sugar and starch increase blood insulin, so even if a feed is labelled low sugar, it may be high in starch
" Low glycaemic index ' Glycaemic index( GI) is determined by measuring insulin, glucose and ACTH before and again every 30 minutes for up to 8 hours after feeding. This research requires a licence and animal ethics approval. Check if the manufacturer has done this for the feed.
AUSTRALIAN QUARTER HORSE ASSOCIATION- www. aqha. com. au