This research investigated the feeding value of Kangar (Gandelia tournefortii) hay and the effect of diets containing this hay on growth performance of Baluchi lambs. Kangar hay was collected from the Khorasan natural rangeland at the stage of late maturity and evaluated in terms of chemical composition, in sacco degradability and a growth study with lambs. Twenty-four male and 24 female lambs were allocated to 4 dietary treatments in a feedlot condition. All groups received a concentrate mixture of 60 and 40% roughage including alfalfa hay (25%), dry wheat straw (15%), soaked what straw (15%), dry Kangar hay (15%) and soaked Kangar hay (15%) as treatments 1-4, respectively. Chemical composition mainly CP of Kangar hay was much higher than wheat straw and even comparable to alfalfa hay. The average DM degradability of Kangar hay was 67.2% after 120 h incubation, but >76% of the incubated DM degraded during the 1st 24 h. These values for CP and NDF were 73.5 and 54.5%, respectively. These parameters ranked Kangar hay as medium-quality forage. Male lambs fed by TMR containing the soaked Kangar hay gained better than other groups. Average daily gains of male and female lambs on dietary treatments of 1-4 were 218, 237, 241, 276 and 197, 215, 229 and 259 g, respectively. The best feed conversion ratio was also recorded for the male lambs on diet containing 15% soaked Kangar hay (6.5 kg feed consumed kg-1 of weight gain). The mean dressing percentage for the lambs allocated to treatments 1-4 were 54.7, 54, 9, 53.4 and 53.5 for males and 53.1, 52.7, 54.0 and 55.7 for females, respectively. It was concluded that inclusion of Kangar hay can be beneficial mainly for smallholder farmers during periods of low rainfall and forage scarcity.

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