RESEARCH ON CHEMICAL COMPOSITION OF CORN SILO OBTAINED IN DIFFERENT PRODUCTION SYSTEMS (CONVENTIONAL AND ORGANIC)

Nadia Mirela Aioanei, I.M. Pop

Abstract
The aim of this work was a comparative analysis of the chemical composition determined for 10 samples of corn silage, derived from two farms in the North-East part of Romania, with different production systems (conventional and organic). The research focused on determining the gross chemical composition (content of dry matter, crude ash, crude protein, crude fat, crude fiber, ADF, NDF and SEN) using Weende scheme and mineral content (Ca and P) by spectrophotometric method. In order to determine the chemical composition, the guidelines were standards like: ISO 6496:2001, ISO 6498:2001, EN ISO 6869:2001, ISO 6492:2001, EN ISO 6865:2002, EN ISO 6497 : 2005. Statistical analysis revealed significant differences between average values for corn silage samples, derived from the conventional system compared with the ecological one for crude ash content (5.11 ± 0.11% Ash vs. 4.11 ± 0.07% Ash) and calcium (0.315 ± 0.005% Ca vs. 0.219 ± 0.001% Ca); distinct significant for crude protein content (7.39 ± 0.10% CP vs. 6.12 ± 0.30% CP), acid detergent fiber (28.00 ± 0.46% ADF vs. 25.94 ± 0.34% ADF) and phosphorus (0.224 ± 0.009% P vs. 0.185 ± 0.003% P); significant for nitrogen free extract substances content (59.66 ± 0.65% SEN vs. 57.00 ± 0.84% SEN). For dry matter, organic matter, crude fat, crude fiber and NDF content, the differences were insignificant.

Key words: organic feed, corn silage, chemical composition, calcium, phosphorus