Feed trials bring weight shortfalls
YOUNG STOCK fed straw, maize gluten and minerals can fail to gain the liveweight predicted, according to a Rumenco trial.
Heifers that fall below their target weights are unlikely to compensate later and will calve at lighter weights, says Rumencos Simon Marsh.
Feeding 4kg of maize gluten at 20% crude protein provided a diet at 12.5% protein. This appears sufficient on many rationing systems for 0.75kg a day liveweight gain but only 0.42kg a day was achieved in the trial, costing £1.19 for each kg of gain.
This was compared with a 28% crude protein mix of 2kg Livet dark grains, 2kg Lactomix, a blend of syrups from the milk, sugar cane and cereal processing industries, and 0.5kg Supercharge – a digestible undegradeable protein supplement containing soya and fishmealThe mix resulted in 0.76kg a day liveweight gain costing only 89p/kg of gain.
The target 15-16% protein diet supplied by the concentrate mix is needed for optimum weight gain and good frame growth, says Mr Marsh. Similar results emerged at Reaseheath College, Cheshire.