Traditional Teratogenic And Subchronic Toxicity Test Of Clostridium Protein Powder Used In Feed In Rats

Objective:The clostridium protein powder with more 80%crude protein was extracted from clostridium waster in biofuel production in Beijing biotechnology company.To develop the application of clostridium protein powder used in feed,the toxicological safety of the powder on rats was evaluated by acute toxicity test,teratogenicity test and subchronic toxicity test.Methods:? Wista rats with same sex were given orally 5000 mg/kg the clostridium protein powder in acute toxicoloty test,and the death rate and other acute toxicity were observed.?In the traditional teratogenic test,Wistar pregnant rats were divided into five groups randomly.The clostridium protein powder was administered to the pregnant rats from 7d to 15d by intragastric administration at dose of 5.0 g/kg b.w.,2.5 g/kg b.w.and 1.25 g/kg b.w.respectively and 1%sodium carboxymethyl cellulose aqueous solution used as normal control,200 mg/kg b.w.aspirin by lavage as positive control.At 20th day of pregnancy,the pregnant mice were sacrificed by cervical dislocation.The parameters such as number of corpus luteum,implantation number,live births rate,litter size,fetal average weight,body length,placental weight and fetal absorption rate etc.were detected.? In the subchronic toxicity on rats,the test subjects were divided into three groups of high,medium and low doses(1%,5%and 10%,respectively)added to the feed and fed continuously for 90 days.The normal control group was fed a conventional diet of rats.Twenty rats with half male and female were in each group.The general behavior and diet of the rats were observed during the test,and the body weight and feed consumption were weighed weekly.At the 45th and 90th day of feeding,10 rats in each group(5 males and 5 females)were autopsied,and anticoagulation blood for blood cytology examine,and serum samples for blood biochemical parameters test like alanine aminotransferase(ALT)and aspartate aminotransferase(AST)etc.The weight of heart,liver,spleen,lung,kidney,ovary and testis were taken to calculate the organ coefficient.The histopathological examination on main organs such as liver,kidney,spleen,lung,stomach,duodenum,testis,ovary were mead by HE staining.Results:The oral LDso value of the powder was more than 5000 mg/kg,and it was belong to the grade of actual non-toxic material based on the grading standard of WHO about toxicity.The results of teratogenic test indicated that the average weight of ovary,number of corpus luteum,implantation number,live births rate,litter size,fetal average weight,body length,placental weight,sex and fetal absorption rate of each group of the protein tested appeared no significant difference with the normal control group(P>0.05).And the result of the parameters of death rate,birth misshapen rate of live rats,deformity of new born rats and the monster rate of mother of each group of the tested powder appeared no significant difference with the normal control group(P>0.05).The live births rate,fetal average weight,placental weight,fetal absorption rate and deformity of new born rats etc.in positive group were all significantly higher than that in negative control(P<0.01).The clostridium protein powder has no observed teratogenic effects on Wistar rats.The 90 days subchronic test showed that the growth and development of the animals were good during the 90-day feeding time.The weight gain,food utilization rate and organ coefficient were not different from that in normal control(P>0.05).The values of TP,ALB,CRE,ALT and AST in 5.Omg/kg b.w.group were higher than the control(P<0.05),but these value were all in normal range of blood routine and biochemical parameters in rat.Other routine blood parameters and blood biochemical parameters in test groups were no difference compared to control(P>0.05).The gross anatomy and histopathological examination revealed no significant abnormal changes caused by clostridium protein powder compared to control.Conclusion:The oral LD50 value of clostridium protein powder was more than 5000 mg/kg,and it was belong to the grade of actual non-toxic material.No obvious teratogenicity and subchronic toxicity of the powder were found,indicating that it may be utilized as a new feed materinal or feed additive in future.