The nutritive value of Lathyrus sativus forage cut at four stages of growth in Gorgan

In order to determination of nutritive value of Lathyrus sativus at four stages of growth، an experiment carried out in Chalaki research station located in the west of Gorgan. This experiment was a completely randomized design by five replications. Stages of growth consisted of: vegetative growth، mid-flowering (50%)، milky seed and milky-dough seed. Dry matter (DM)، crude protein (CP)، ether extract، ash، gross energy (GE) and acid detergent fiber (ADF) were measured in the laboratory. So، digestibility dry matter (DDM) and total digestible nutrient (TDN) were calculated with accounting formula. Result of the analysis showed that DM and ADF concentration increased when plant age increased and reached to doughy stage (P<0. 05). In contrast، DDM and TDN decreased as age increased (P<0. 05). Gross energy and organic matter content were not significant different at four stages. The highest percentage CP and EE were observed in mid-flowering stage (P<0. 05). The results shown that lathyrus sativus had suitable nutritive value and the best stage for forage harvesting is mid-flowering.