In vitro Gas Production and Fermentation Parameters of Some Plants Species Collected from Algerian Arid Rangelands

The objective of the study was to evaluate the nutritional value of some native plants, collected from Algerian arid zones by in vitro gas production method. The volatile fatty acids (VFA) of samples were also determined in the culture medium. This work was carried out in 2011 and was conducted in comparison to a control substrate (oat vetch) considered as a reference plant in literature. The selected plants were collected in the arid areas of the Algerian desert. Nine forages including six dicotyledon plants (Atriplex halimus L., Artemisia campestris L., Artemisia herba-alba subsp. valentina, Astragalus gombiformis Pomel, Spartidium saharae (Coss. & Dur.) and Retama raetam Forssk., and three monocotyledon plants (Stipagrostis pungens (Desf.), Lygeum spartum L.and Stipa tenacissima L.) were selected. A. campestris, A. gombiformis and A. herba-alba recorded the highest values of gas production. The total VFA production of the different substrates is significantly different between them (p<0.0001). A. gombiformis had the highest total VFA (34.7 mmol/L) followed by A. campestris (32.8 mmol/L), while the lowest total production of VFA was observed in S. tenacissima (17.3 mmol/L). Generally, the plant studied can be classified in two groups, one group with poor-quality grasses (L. spartum. and S. tenacissima) and other with higher digestibility (A. gombiformis and Artemisia spp.). In conclusion, dicot species are therefore recommended for feeding ruminants.