Effects Of Silvopastoral System On Quality Broiler Production

In oder to develop a profitable Forest-Herbage-Broiler ecological feeding model, the quality broilers were grazing under cinnamomum camphora plantation planting with herbage, the playground been set up in the closed forest where near the hencoop for the feeding and resting of chicken .According to the densityes of grazing and canopy closure, the experiment was allotted into three test groupⅠ,ⅡandⅢfollowed different densityes from low to high, the control group (CK) was the floor-rearing in greenhouse. The changes of ecological benefits of different grazing model and the blood's biochemical slaughter traits and meat quality of the quality broilers indices been compared. The research shows:There had a significant effect of canopy closure on microclimate of Silvopastoral system, comparing with the open forest, the closed forest can decrease the temperature of hayashiuchi at the noon of summer which also reduce solar radiation, increase the humidity and improve the microclimate of forest. The growth rate of trees in test groupⅠwas significantly lower than that ofⅡ(P﹤0.01) andⅢ(P﹤0.05). The available concentrations of phosphonium and kalium in the 0~10cm soil layer in test groupⅠwere significantly lower than that ofⅡandⅢ(P﹤0.01). The degradation of grassland in test groupⅠwas significantly lower than that ofⅡas well as the increasing of quality broilers'herbage intakes in test groupⅠ.Furthermore, the average daily gain of quality broilers in test groupⅠwas higher thanⅡ(P﹤0.05) andⅢ(P﹤0.01) during their lifespan, feed conversion ratio ofⅠwas lower than that ofⅡ(P﹤0.05) andⅢ(P﹤0.01);the death and culling ratio ofⅠwas lower thanⅡandⅢ(P﹤0.05).There was no significant difference in the blood biochemical indices between different feeding models. Comparison between test groups shows, accompany with the increasement of the density of grazing and canopy closure, serum urea nitrogen rised, serum total protein and albumin declined. Comparing with control group, the dressing percentage, semi-eviscerated percentage and eviscerated percentage in the test groups of cocks were significantly increased (P<0.05), abdomen fat percentage was significantly decreased (P<0.05); the semi-eviscerated percentage and eviscerated percentage ofⅠa ndⅡwere higher thanⅢ( P﹤0.05). The cocks'spleen indices, glandular stomach indices, testisi indices in the test groups were higher than the control group(P<0.05); the hens'heart indices and the cocks'gizzard indices in test groupⅠandⅡrespectively, were higher thanⅢ(P<0.05); the spleen indices of cocks in the test groupⅠwas higher thanⅢ(P<0.01), and the gizzard indices of hens in the test groupⅠwas higher thanⅢ(P<0.05). The results from the tests of meat quality showed that the chest muscle of the lightness in the groupⅠandⅡwere significantly higher than CK(P<0.05), redness in test groups was significantly lower than CK(P<0.05), yellowness in test groupⅠwas significantly higher thanⅢand CK (P<0.05); the shear force of chest muscle of hens in test groupⅠw as significantly lower than CK(P<0.01) andⅢ(P<0.05); the lipid contents of chest muscle in test groupⅠwas significantly lower thanⅢ(P<0.05); the inosinic acid of hens'leg muscle in test groupⅠw as significantly higher than CK , test groupⅡ(P<0.05) andⅢ( P<0.01).The experiment shows: Forest-Herbage-broiler ecological feeding model under the combination of closed open forest provided the quality broilers with suitable climate, vast wandering space and plentiful supply of food. The low density of grazing helped to protect ecological environment,increase the herbage intake, promote broilers'growth and development, and improve the meat quality.