Study On The Combination Mode Of Ramie-Meat Rabbit Breeding

Ramie（Boehmeria nivea L.Gaudich.）is a traditional specialty fiber crop in China,accounting for 90%of the world’s production and cultivation area.The conventional cultivation pattern of ramie is to harvest fiber in 3 seasons（first,second,and third）,in which the first hemp accounts for 50%of the annual production and has the best quality,while the second and third hemp often have lower quality and yield due to drought,etc.The core problems of ramie cultivation are inefficient utilization and high stripping cost.In the traditional cultivation model,fiber utilization accounts for only 10%of the total biomass,and the cost of stripping raw hemp accounts for 50%of the total cost.In order to reduce the cost of ramie cultivation,it is necessary to change the model of harvesting fiber for three seasons a year to a model of harvesting fiber for the first crop and feed for the second crop,where the young leaves are fed to herbivores and the animal manure is returned to the fields.It is of great significance to reduce the cost of ramie harvesting and improve the planting efficiency.In this study,120 30-day-old meat rabbits were added 0%,5%,10%,and 20%ramie feed to the conventional feed to observe the growth of meat rabbits and to investigate the effects of ramie as feed on the growth and development and nutritional value of meat rabbits.A randomized group experiment was conducted in the field to collect rabbit manure as organic fertilizer,and four treatments of no fertilizer（CK）,all organic fertilizer（T₁）,50%organic fertilizer+50%inorganic fertilizer（T₂）and all inorganic fertilizer（T₃）were set up in the ramie winter cultivation to investigate the effects of fertilization treatments on the yield and quality of ramie head hemp and post-crop fodder,and to analyze the economic benefits of the two harvest modes of fibre for head hemp and fodder for post-crop fodder under the fertilization mode.The main results are as follows:1.The diets supplemented with different levels of ramie feed mainly affected the growth performance,slaughter performance and intestinal villus height of rabbits.Compared with the control,the average daily body weight and relative body fat content of the 10%ramie replacement group increased significantly（19.31%and 57.00%,respectively）;the intestinal villus height of the rabbits was significantly lower at 5%and10%addition levels,which indicated that the 5%and 10%ramie diets were beneficial to the intestinal digestion and absorption of the rabbits.The addition of 10%ramie in the diet could increase the yield of rabbits while promoting digestion.2.The T₂treatment was the most effective in enhancing ramie fiber yield in the fiber-fed two-harvest model,with ramie biomass,fresh bark weight,fresh bark yield and fresh stem yield increasing by 186.20%,352.25%,42.85%and 14.97%,respectively,compared with CK.Compared with CK,the gum content of head hemp fiber in T₂treatment was significantly reduced（decrease of 16.70%）,the breaking strength of T2-treated head hemp fibers increased by 13.10%,and the elongation of T₂and T3-treated head hemp fibers increased significantly（by 101.31%and 46.50%,respectively）.3.The combination of organic and inorganic fertilizers could maintain soil fertility levels longer while improving the yield and quality of ramie postharvest fodder.In this study,ramie was harvested after the first hemp and the subsequent three crops were harvested as fodder.Compared with CK,the first ramie fodder crop under T₁,T₂and T₃treatments increased fresh grass yield by 87.84%,93.99%and 54.97%,hay yield by70.42%,72.03%and 44.70%,ash content by 13.35%,21.20%and 5.40%,crude protein yield by 87.12%,99.63%and 41.75%,respectively.There was no significant difference in crude protein content;the second crop of ramie forage increased by 17.70%,26.88%and 14.77%in fresh grass yield,21.66%,41.47%and 18.43%in hay yield,16.41%,12.75%and 4.65%in ash content and 27.01%,17.25%and 27.27%in crude protein content respectively,17.25%and 27.27%,crude protein yield increased by 53.77%,65.04%and 50.42%;third crop ramie fodder yield increased by 8.97%,17.18%and8.97%,respectively,with no significant difference in hay yield and ash content increased by 21.24%,24.75%and 6.61%.There was no significant difference in the RFV of the first and third crop of ramie forage,while the RFV of the second crop under T₁and T₃treatments were 116.99 and 116.80,respectively,which were significantly higher than the control（101.94）.4.The combined ramie breeding and feeding model can yield higher benefits.The net profit of ramie in this study was 1349.51 RMB/667 m²and the profit of meat rabbit was 75.92 RMB/each.Compared to the monoculture or farming model,it can reduce the cost of feed and fertilizer,and the cost of ramie harvesting is only 674.6 RMB/667 m².5.Organic fertilizer application improved the utilization of 6 types of carbon sources by soil microorganisms.Compared with the control,the AWCD（average color change rate）of carbon sources increased under T₁,T₂and T₃treatments,and the growth order was T₂>T₁>T₃>CK.Simpson index,Mc Intosh index,Shannon index and richness index（S）of ramie soil microorganisms under T₁,T₂and T₃fertilization treatments were significantly different from the control,with the best results under T₂treatment.The Simpson index,Mc Intosh index and richness index（S）were T₂>T₁>T₃>CK,and the overall trend of carbon utilization ability of T₃treatment was similar compared with the control.In conclusion,the 5%and 10%ramie content in the feed promoted the growth performance of rabbits with no adverse effect on meat quality.50%organic fertilizer+50%inorganic fertilizer treatment improved the yield and quality of ramie head fibre and improved the yield and quality of post-crop feed.Organic fertilizer increased soil microbial community diversity and improved the utilization of carbon sources,thus improving the nutrient status in the soil.The combined ramie-meat rabbit breeding and feeding model improved economic and environmental benefits.