The objectives of this study were to examine the botanical composition and determine the nutritive value of pastures in 9 different locations in Kars district with respect to stages of maturity. Samples were collected bi-weekly from 21 May to 30 July 1999. The Gramineae, Leguminoseae and other plant families constituted 64.2, 22.8 and 13.0% of the plant population, respectively. There was a variation in the nutrient composition of samples collected from different locations (P < 0.05). Average dry matter (DM) content was 28.8% and concentrations of organic matter (OM), crude protein (CP), crude fiber (CF), neutral detergent fiber (NDF), nitrogen-free extract (NFE), ether extract (EE) and ash on a DM basis were 90.8, 15.3, 30.0, 57.6, 43.4, 2.0 and 9.2%, respectively. Stage of maturity altered nutrient composition (P < 0.5). Concentrations of OM, NFE and ash did not change, CP linearly decreased, and CF and NDF quadratically increased with advancing maturity. In conclusion, the Gramineae were the predominant flora of pastures in northeastern Turkey. Moreover, mathematical models developed to characterize changes in the nutrient composition of pastures with advancing maturity may help to improve current feeding strategies.

The objectives of this study were to examine the botanical composition and determine the nutritive value of pastures in 9 different locations in Kars district with respect to stages of maturity. Samples were collected bi-weekly from 21 May to 30 July 1999. The Gramineae, Leguminoseae and other plant families constituted 64.2, 22.8 and 13.0% of the plant population, respectively. There was a variation in the nutrient composition of samples collected from different locations (P < 0.05). Average dry matter (DM) content was 28.8% and concentrations of organic matter (OM), crude protein (CP), crude fiber (CF), neutral detergent fiber (NDF), nitrogen-free extract (NFE), ether extract (EE) and ash on a DM basis were 90.8, 15.3, 30.0, 57.6, 43.4, 2.0 and 9.2%, respectively. Stage of maturity altered nutrient composition (P < 0.5). Concentrations of OM, NFE and ash did not change, CP linearly decreased, and CF and NDF quadratically increased with advancing maturity. In conclusion, the Gramineae were the predominant flora of pastures in northeastern Turkey. Moreover, mathematical models developed to characterize changes in the nutrient composition of pastures with advancing maturity may help to improve current feeding strategies.