Effect of harvest stages of maize hybrids on crude protein degradability
2003
Ulrichova, Z.,Research Institute of Animal Production, Nitra (Slovak Republic) | Ceresnakova, Z.
The aim of this study was to determine crude protein degradability using the in sacco method for the grain of chosen maize hybrids (Dirk, Diana, Fjord and Turini) at different maturing stages of grain. The grain was harvested in a foothills area (Liptovsky Mikulas, northern SR) from 18th September to 16th October 2001 at weekly intervals. In sacco experiments were carried out on three cannulated non-lactacing Black-White Pied cows with large rumen cannula (diameter 10 cm) of live weight 630 kg. Cows were fed twice daily. Feeding ration consisted of maize silage, alfalfa hay, barley, wheat grist and Vitamix S1. Sacks made from Uhelon T-130 containing 15 mg samples quantum were inserted into the rumen immediately before feeding. Non-degraded contents were weighed after washing and drying, then milled and used for chemical analyses. The crude protein degradability of individual incubation was calculated by Microsoft Excel and the effective degradability at a speed of 0.06 and 0.08% per h by the Neway program. The effective degradability of maize grain decreases with increasing maturity. It is best therefore to gather maize grain at the optimal maturing stage when the effective degradability of crude protein in rumen also shows a decreasing tendency.
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