تأثیر مرحله رشد بر ترکیبات شیمیایی و اثرات عمل آوری سود و آهک بر ترکیب شیمیایی و مولفه های تجزیه پذیری گیاه مرتعی تاغ (Haloxylon sp.) در مرحله بذردهی

This experiment was done to determine the effectd of growth stage on chemical composition and processing by NaOH and CaOH2 on ruminally degradability of Haloxylon sp. pasture plant in seeding stage. The enough amount of Haloxylon in 3 vegetation stages was prepared from Amari SarChah in May and October and December of 2010. The chemical composition of Haloxylon sp. was determined in three stages of vegetative growth, flowering and seeding. The processing samples of maturity stage with NaOH and CaOH2was done in plastic bags and chemical composition and degradability characteristics was determined. The level of crude protein and ash reduced with the progress in growth stage and level of neutral detergent fiber increased. In the samples processed by NaOH and CaOH2 compared with the samples which were not processed, level of crude protein and ash increased and level of neutral detergent fiber reduced. Degradation coefficient a of crude protein in the samples processed by CaOH2 significantly increased compared with other treatments. Coefficient b of crude protein processed by NaOH significantly increased compared with other samples. Degradation coefficients a andbfractionof NDF showed significant difference between the samples. Therefore, the results demonstrated that, with the increase in growth stage, protein level of Haloxylon sp. plant decreased and its NDF and ADF levels increased. Moreover, processing Haloxylon sp. pasture plant by NaOH and CaOH2 caused degradation increase of dry matter, crude protein and NDF.