Estimating pasture intake and nutrient digestibility of growing pigs fed a concentrate-forage diet by n-alkane and acid-insoluble ash markers

A study was carried out to determine voluntary forage intake and nutrient digestibility in growing pigs fed a mixed forage and concentrate diet. Twenty-five 8-week-old Large White?×?Landrace crossbred male pigs (27?±?3.8?kg) were blocked by weight into five groups, and each was randomly allocated to four indoor treatments (A, B, C, and D), which received 100, 90, 80, and 70?% of ad lib concentrated intake and an outdoor treatment (E) that received 80?% of ad lib concentrate. Indoor treatments were either fed the concentrate only (A) or also received freshly cut Kikuyu grass (Pennissetum clandestinum) ad libitum (B, C, and D), while pigs on treatment E were reared outdoors in Kikuyu grass paddocks. There was a significant correlation between the amount of concentrate offered and its intake (P??0.05). Mean acid-insoluble ash digestibility estimates of organic and dry matter were superior to C(32) estimates (P?