Research Regarding Crude Chemical Composition and Heavy Metal Content of Some Ecological Forages Utilised in Dairy Cows Nourishment

Abstract

Kowing the importance of utilised food for milk obtaining, in the current paper we determine the chemical composition of a natural meadow and green mass alfalfa cultivated in ecological and conventional systems, utilised for dairy cows feeding. Were analysed the content in: dry matter DM (%), crude ash C.Ash (%), organic substance OS (%), crude protein CP (%), crude cellulose CC (%), non-nitrogenous extractive substances NES (%), neutral detergent fibre NDF (%), acid detergent fibre ADF (%), Ca (%), P (%), heavy metals (Pb, Cd, Zn, Cu - ppm), nitrates, nitrites and pesticides. Analysis were realised in two consecutive production years, for each indicator being made 5 determinations. Samples gathering and analysis were effectuated in according with standards and enshrined working methods. Differences between crude chemical composition of forages obtained in ecological system and the ones obtained by conventional agriculture had statistical significance (from significant - p ≤ 0.05 - to very significant - p ≤ 0.001) for the majority of indicators. Differences between those two production systems were insignificant only for crude fat (both forages), crude cellulose (alfalfa), non-nitrogenous extractive substances (both forages) and for acid detergent fibre (alfalfa). Both forages were safety regarding pollutants (heavy metals, nitrites, nitrates and pesticides), existing however statistically differences between those two production systems, in the favour of ecological