Broussonetia Papyrifera Feed Fermentation And Nutritional Value Of The Feed

Broussonetia papyrifera, a kind of deciduous tree, grown in most parts of China, and the crude protein content of the Broussonetia papyrifera leaf come to 18-24%, has great development potential as unconventional resources. The present study was used to?screen suitable microbial strains and fermentation conditions to improve the feeding value of Broussonetia papyrifera, and provide a scientific basis for the further development of Broussonetia papyrifera feed resources.(1)With selection media, two bacteria strains GZ₃ and HS₃ were isolated and screened from the rhizosphere soil of theBroussonetia papyrifera and sugarcane, both of GZ₃ and HS₃ were Gram-negative bacteria and facultative anaerobes,and the optimum growth pH 5.0- 8.0, the optimum growth temperature is 30-35℃. The crude protein content of GZ₃ and HS₃ ferment Broussonetia papyrifera leaf increased by 8.32% and 5.33% respetively, and the crude fiber content decreased by 14.96% and11.68% respectively.(2) With L16 (3×43) orthogonal design, without considering the interaction between factors, the ferment parameters, pH value, temperature, inoculation quantity, and fermentation time were optimized. of fermentation conditions. The result indicated that, for GZ₃ stain, the rational ferment parameter was: ferment temperature 35℃, medium pH 7.0, inoculation quantity 2%, ferment time was 6 days; for HS₃ strain, the rational ferment parameter was: ferment temperature 45℃, medium pH 6.0, inoculation quantity 1%, ferment time was 6 days. The mixture of Broussonetia papyrifera leaves were subsequently fermented under the optimized conditions above, the GZ₃?strain had the best effect on the crude fiber degradation, while the HS₃ strain had the best effect on protein hydrolysis.(3) The 16SrRNA gene fragments of the GZ₃ and HS₃ strain were amplified and cloned by PCR. The ncleotide sequence analysis showed that both of GZ₃ and HS₃ belong to Bacillus genera.(4) The mixture of Broussonetia papyrifera leaves were fermented by strain GZ₃ and HS₃ respectively and nutritional components of the mixture were analyzed before and after fermentation. Then, fermented leaves were added to the diets of AA broilers and the effects of the leaves on metabolism and growth performance were observed. Feeding experiment had four groups, each with 5 repetitions, 8 chickens each rerepetition: basal diet group (control group), unfermented Broussonetia papyrifera Leaves group (group 1), GZ₃ fermented group (group 2), HS₃ fermented group (group 3). The results showed that: 1) After fermentation, the crude fiber in the leaves decreased and the crude protein significantly increased. Specifically, compared with unfermented group, the crude fiber content in Group 2 decreased by 11.58%, and was significantly lower than that that of other groups (p <0.05); the crude protein content increased by 9%. 2) No negative effects on the growth of broilers were observed for Broussonetia papyrifera leaves supplementation in the diets. The feed conversion ratio of the control group during 1-42 days of age was 1.88±0.04, slightly lower than that of group 2 and group 3, the differences were not significant, but significantly higher than that of Group 1 (p <0.05). 3) AA broiler had a good digestion with basal diet; followed by Group 2, Group 3 and Group 1.(5) 2 42-day-old AA chickens were randomly selected from each repetition to determine their slaughter performance and meat quality index. The effects of fermented Broussonetia papyrifera leaves on the slaughter performance and meat quality of AA broiler were discussed. The results showed that: 1) The dressing percentage, breast muscle percentage, leg muscle percentage and abdominal fat percentage of four groups were no significantly different (p>0.05). Abdominal fat percentage, subcutaneous fat thickness and width of intermuscular fat of the animals in group 2 were slightly lower than than that of other groups; the subcutaneous fat thickness and width of intermuscular fat of the birds in group 2, group 3, and group 4 fed with Broussonetia papyrifera leaves were significantly lower than that of control group (p>0.05). Moreover, in Group 2, subcutaneous fat thickness than the control group was significantly decreased 8.75%, width of intermuscular fat than the diet group was significantly decreased 10.02%. 2) Basal diet supplemented with fermented Broussonetia papyrifera leaves can increase muscle pH, reduce muscle drip loss and cooking loss, increase muscle water holding capacity, improve the quality of AA broiler meat. 3) The inosinic acid and IMP + HxR contents of the breast muscle in Group 3 were the highest, compared with control group increased 42.16%. The inosinic acid and IMP + HxR contents of the leg muscle in Group 1 were the highest, significantly higher than other groups (p<0.05), compared with control group increased 39.31%.