The Study On Growth And Reproduction Of Earthworm Affected By Adding Amendment To Its Feed Of Livestock And Poultry Waste

The rapid development of animal husbandry in China has made the great contribution to improve the living standards of our people, but it brings great challenges to the environmental protection at the same time. Earthworm composting is a biological fermentation widely used in livestock manure decomposition.Livestock and poultry manure can not only effectively release the environmental pressure, but turn waste into resource maximally. For the time being, studies of earthworm focus mainly on treatment efficiencies of livestock and poultry manure, while few ones focus on the use of conditioning agents to improve the growth and reproduction of earthworm. Therefore, this study investigate the effect of agents on the growth and reproduction of earthworms by adding conditioning agents in animal excrement to improve the nutrition of materials to provide technical reserves for earthworm efficient farming and the processing of organic waste.In this paper, we regarded Eisenia fetida belonging to adolescent earthworms and adult breeding earthworms as the object of study, and use sodium citrate, potassium hydrogen phosphate and urea as conditioning agents to explore the effect of the conditioning agents on earthworms growth and on the amount of cocoon production of the adult breeding earthworms, and then find the most suitable level of conditioning agents added for the growth and reproduction of earthworms. According to the results of preliminary experiment, sodium citrate and urea respectively set up 8 concentration gradients, and potassium hydrogen phosphate sets up 9 concentration gradients, each concentration has three repeating groups. In the test, via single-factor controlling variable method, we add separately the sodium citrate and potassium hydrogen phosphate into the livestock and poultry sludge, the potassium hydrogen phosphate and urea into cow dung, and then set different concentration levels, which are used to feed adolescent earthworms and adult breeding earthworms. In the beginning of the test, there are 15 earthworms in each experimental group, the weight of each adolescent earthworm is 175±15mg(the total of 15 earthworms is 2625±25mg), we weighed the total earthworms in each experimental group weekly and recorded, the test lasted for 7 weeks with the livestock and poultry sludge as base material, and the test with the cow dung as base material lased for 6 weeks; The weight of each adult breeding earthworm is 550±25mg(the total of 15 earthworms is 8250±50mg), we weighed the total earthworms in each experimental group and counted the amount of Cocoon production weekly, then recorded the data accurately, lasting for 4 weeks; Meanwhile, we detected the total carbon, total nitrogen, carbon and nitrogen ratio, pH and total phosphorus of the base material. Research indicates:1. The reasonable level of sodium citrate, potassium hydrogen phosphate and ureahas a role in promoting growth and reproduction of the earthworms, excess level will reduce the effect; the effect of conditioning agents is time-sensitive, therefore the conditioning agents need to constantly replenish.2. The most reasonable levels of conditioning agents on promoting the weight gain of adolescent earthwormindividual, promoting theweight gain of adult breeding earthworm individual, or promoting the amount of Cocoon production of adult breeding earthworm individualare different:The most reasonable level of sodium citrate added into the livestock and poultry sludge for feeding the adolescent earthworms is 1000mg/kg, the average weight of a single earthworm is 0.6249g after 4 weeks; The most reasonable level of sodium citrate added for promoting the weight gain of the adult breeding earthworm individual is 3500mg/kg, the average weight of a single earthworm is 0.8019g after 4 weeks; The most reasonable level of sodium citrate added for increasing the cocoon production of adult breeding earthworms is 7000mg/kg, The averagecocoons yielded per earthworm is 3.44 after 2 weeks.The most reasonable level of potassium hydrogen phosphate added into the livestock and poultry sludge for feeding the adolescent earthworms is 3000mg/kg, the average weight of a single earthworm is 0.6583g after 4 weeks; The most reasonable level of potassium hydrogen phosphate added for promoting the weight gain of the adult breeding earthworm individual is 1000mg/kg, the average weight of a single earthworm is 0.8922g after 3 weeks; The most reasonable level of potassium hydrogen phosphate added for increasing the cocoon production of adult breeding earthworms is 3000mg/kg, The averagecocoons yielded per earthworm is 3.91 after 2 weeks.The most reasonable level of potassium hydrogen phosphate added into cow dung for feeding the adolescent earthworms is 3000mg/kg, the average weight of a single earthworm is 0.7601g after 3 weeks; The most reasonable level of potassium hydrogen phosphate added for promoting the weight gain of the adult breeding earthworm individual is 2000mg/kg, the average weight of a single earthworm is 0.9079g after 2 weeks; The most reasonable level of potassium hydrogen phosphate added for increasing the cocoon production of adult breeding earthworms is 3000mg/kg, The averagecocoons yielded per earthworm is7.09 after 2 weeks.The most reasonable level of urea added into cow dung for feeding the adolescent earthworms is 5000mg/kg, the average weight of a single earthworm is 0.6592g after 3 weeks; The most reasonable level of urea added for promoting the weight gain of the adult breeding earthworm individual is 5000mg/kg, the average weight of a single earthworm is 0.9260g after 3 weeks; The most reasonable level of urea added for increasing the cocoon production of adult breeding earthworms is 4000mg/kg, The averagecocoons yielded per earthworm is5.27 after 2 weeks.3. After the Eisenia fetidabeing grown up,the phenomenon of weight of earthworm individuals approaching a weight limit would happen sooner or later; and the final body weight can’t be significantly affected by the growth rate and feeding conditions.4. The change of total carbon in base materials will be affected by the type and additional level of conditioning agents, the growth stage and growth rate of earthworms and the type of base materials.5. The C/N in cow dung has no significant effect on the growth of adolescent earthworms (P>0.05), but has significant effect on the growth and reproduction of adult breeding earthworm (P<0.05).