Effect Of Nutrients On Gut Microbiota Of Black Soldier Fly And Influences Of Dry Larvae On Growth Performance Of Weaned Piglets

Black soldier fly,Hermetia illucens L.,rich in nutrients,especially proteins,can be used as protein feedstock in poultry and aquaculture.However,it is still difficult for black soldier fly larvae to carry out large-scale industrial production.The main reason is that large-scale rearing and application parameters are lagging behind.It has great practical significance to study the breeding of black bream and its production and application.In this study,We take a four-day-old larvae of black soldier fly as the research object,an orthogonal test was designed to calculate the protein,carbohydrate,fat,fiber,and energy contained in each group according to the nutrient components of the raw materials,and analyze the effect of different gradients of individual nutrients on the larvae.influences.Based on the larval growth and feed characteristics,16 S rRNA technology was used to detect and analyze the effects of different ratios of feed on the gut microbiota of the black soldier fly larvae.Isolation of black soldier fly intestinal microorganisms were used to ferment soybean dregs.Four-day-old black soldier fly larvae were reared.The survival rate,pre-tiller weight gain,feed-to-weight ratio,and conversion rate were calculated,and the economically valuable strains were identified to exploring the effect of Intestinal Microorganisms on the growth and development of black soldier fly.Plasma protein powder,fish meal and black soldier fly powder were used to feed 40 days old Du × long × large weaned piglets.Materialization analysis the three components and based on the ingredients to feed the pigs.Among them,plasma protein powder and fish meal were blank control group,and black water powder was the experimental group.The growth performance of weaned piglets was compared by comparing the growth performance of piglets.The result is as follows:(1)Statistical analysis of the results of feeding 25 formulas: The optimal formula for breeding black larvae is 20% lean meat+25% lettuce + 0% peanut oil(with 55% rice).The highest conversion of the feed for breeding of black soldier fly larvae is that carbohydrate content is 7.82-13.75%,protein is 1.69-9.52%,fat is 0.30-12.62%,cellulose is 0.15-0.47%,and energy is 67.20-101.68 kcal/kg.(2)Foods fed different nutrient components caused differences in the relative abundance and population structure about the intestinal microorganisms of the black-water larvae.The composition of the intestinal flora in the four experimental groups was not significantly different at the levels of gates,classes,orders,and families,but there was a obvious difference at the genus level.(3)Three types of bacteria were isolated from the intestinal microorganisms of black sea bream(L1,L2,and L3).The blank group and three groups of strains fermented bean dregs feed four-day-old black water larvae.Compared with the other three groups,L3 had the best performance in pre-grass weight gain,survival rate,feed-weight ratio and conversion rate.Identification of L3 strains is the Bacillus and Paenalcaligenes.(4)After raising piglets for 25 days,The ratio of the number of E.coli and lactic acid bacteria the in the piglets fed with plasma protein powder,fish meal,and black water powder were 0.156,0.75,and 1.15,respectively.The results showed that the best plasma protein powder was fish meal,followed by fish meal,and black soldier fly powder was the lastest for regulating the microbial ecological balance of piglets' intestinal tract and ensuring intestinal health.(5)When piglets were fed with plasma protein powder,fish meal and black water powder,the black water powder is the best in the average daily weight gain and the ratio of feed to weight.In the diarrhea rate,the plasma protein powder group was the smallest.5.60%,followed by black water powder group,reached 6.28%.However,the above indicators were not significantly different among groups(P>0.05).According to the weighted average daily weight gain(50%),feed weight ratio(30%),and diarrhea rate(20%),weighted total scores for plasma protein powder,fish meal,and black water aphid powder were 4 points,7.25 points and 5.5 points,that is,the effect of raising piglets,fish meal> black water powder> plasma.Therefore,the use of black water powder instead ofplasma protein powder and fish meal can be considered for feeding piglets.