Determination of digestibility of almond hull in sheep
A study was conducted to determine the chemical composition and digestibility of almond hull using in vitro, sacco and vivo methods. Chemical compositions of almond hull and alfalfa hay were determined. The crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) of almond hull were lower than those of alfalfa hay but the non fibrous carbohydrate (NFC) was more than that of alfalfa hay (3.5 times) (P < 0.01). The dry matter disappearance of almond hull for all incubation times using in sacco method was greater than that of alfalfa hay (P < 0.01). To measure in vivo digestibility, four mature Moghani sheep of live weight (39 ± 3 kg mean±SD) were used in a 2 × 2 change over design. Diets consisted of a basal diet (alfalfa hay) and a mixed diet (alfalfa hay 70% + almond hull 30%). Invitro and vivo dry matter digestibilities of almond hull were 585.8 and 645.0 gkg-1, respectively. There was no difference between in vivo dry and organic matter digestibility of alfalfa hay and mixed diet but were significantly affected in the case of CP and NDF (P < 0.01). In general, almond hull had low CP but greater NFC content as well as greater digestibility in sheep.
Key words: Almond hull, by-product, chemical composition, digestibility, in vivo.