摘要：This study was set up to evaluate the effect of different dietary levels of guar meal (GM) on productive performance of laying hens. One hundred and eighty 25-weeks-old Hisex laying hens were randomly distributed among 5 treatments with 6 replicates of 6 hens each. Hens were fed layer diets supplemented with either 0.0, 2.5, 5.0, 10.0 or 20.0% GM for 8 weeks trail period (25 to 33 weeks). Body weight, mortality rate, body weight gain, egg production, feed consumption, feed conversion ratio, egg weight, egg mass, egg specific gravity, Haugh unit and egg yolk color were recorded. The results obtained in the present study showed that final body weight and body weight gain were significantly the lowest in hens fed 10.0 and 20.0% GM when compared with the other treatments, but no significant differences were noticed among hens fed either 0.0, 2.5, 5.0, or 10.0% GM. Mortality rate was significantly higher in hens fed 0.0% GM than those fed 5.0 or 20.0% GM, but no differences were observed between hens fed either 2.5 or 10.0% GM and the other treatments. Hens fed 20.0% GM showed significantly the lowest egg number and percentage produced, feed consumption, egg weight, and egg mass per hen when compared with the remaining treatments. However, hens fed 20.0% GM exhibited the highest feed conversion ratio and egg specific gravity when compared with the other treatments. Hens fed 5.0 and 10.0% GM produced eggs with more yellowness values than those fed 0.0% GM, but there were no differences between hens fed either 2.5 or 20.0% GM and the other treatments. We conclude that GM can be added into diet up to 10.0% without adverse effects on productive performance of laying hen.
