تعیین ارزش غذایی پنج گونه از گیاهان شورپسند منطقه سیستان با استفاده از تکنیک تولید گاز (in vitro) و کیسه نایلونی (in situ)

This study carried out to determine of chemical compositions and nutritive value of five species of range plants in Sistan including Oshnan (Seidlitzia rosmarinus), Rendouk (Salsola yazdiana Assadi), Siyah Shor (Suaeda fruticosa), Shoran (Salsola vermiculata) and Anabasis (Anabasis setifera) by in vitro and in situ techniques. Samples were collected by systematic and random sampling procedure in autumn according to standard methods. The samples were dried in shade and after milling, chemical compositions including dry matter (DM), organic matter (OM), ash (ASH), crude protein (CP), crude fat (EE), cell wall (NDF) and cell wall- hemicellulose free (ADF ), dry matter degradability (in situ), cumulative gas production at 2, 4, 6, 12, 24, 48, 72 and 96 h, the organic matter digestibility (OMD) and metabolisable energy (ME) were determined. The results of this experiment showed that, there were significant differece in terms of chemical compositions of these samples (p<0.05).  Crude  protein, ADF and NDF contents were between 6.05 and 11.95%, 28.02 and 36.54%  and 41.14 and 48.94% respectively. There was significant difference (p<0.01) between dry matter degradability, degradability parameters and effective degradability in different incubation times. The maximum potential degradability and effective degradability (k= 0.02) was in Oshnan species. Also, the maximum cumulative gas volume at 96 hours was related to Rendouk. But, the gas production parameters (b, OMD, ME) in Oshnan species was higher than other species. The results showed that in these plants, Oshnan species has the highest nutritive value and also, there was a high positive correlation between in situ and in vitro experiments in these species and can use the gas production technique for assessing of nutritive value of these species.