بررسی ارزش غذایی سطوح مختلف علوفه سیب زمینی ترشی(Helianthus tuberosus)و یونجه با روش های برون تنی و درون تنی (گوسفند)

This research was conducted to study the nutritive value of Jerusalem artichoke (JA) as animal feed. The aerial part of the JA plant was harvested, at full bloom stage, and then chopped and dried. The chopped JA hay included 0.0, 10, 20, 30 and 40 % of alfalfa hay, used as experimental diets, and tested for in vitro digestibility. In a changeover experiment with Latin square based design the in vivo digestibility was studied by sheep. The samples of dried JA forage as well as the experimental diets were collected and analyzed chemically. The nutrient contents of JA were relatively similar to alfalfa hay except for the crude protein that was lower in JA. The in vitro dry mater and organic mater digestibility were not affected by the levels of JA in the diets, but the digestible value reduced (p<0.05) when the JA ratio was increased to the 40% of the diet. The in vivo digestibility of dry mater, organic mater and fiber fractions was decreased in the diet containing 40 percent JA however, total digestible nutrients and metabolisable energy were not significantly different among the treatments. It may be concluded that nutritive value of JA is similar to alfalfa hay, when it is used up to 30% instead of the alfalfa hay based diet