Effects Of Flammulina Velutipes Stem-base On Performance And Lipid Metabolism Of Layers During The Whole Period Based On Meta-analysis

China is the world’s largest producer and consumer of edible mushrooms,with an annual output accounting for more than 70% of the global total.Apart from their nutritional value,the reuse of edible mushroom waste is also of great significance.With the continuous development of mushroom production,a large amount of waste is generated,including mycelium,spores,and cultivation substrates,which not only occupy a lot of land and resources but also cause environmental pollution.Research has found that edible mushroom waste mainly contains various proteins,polysaccharides,amino acids,trace elements,etc.,which have high nutritional value and biological activity,and can improve animal immunity,promote growth and development,and improve meat quality.The use of edible mushroom waste in feed research has broad development prospects.It can not only reduce feed costs,improve breeding efficiency but also reduce resource waste and environmental pollution,which is in line with the concept of sustainable development.In the production of shiitake mushrooms,the waste stems(Flammulina velutipes stem-base,FVS)are the stem base part of the mushrooms,and multiple studies have shown that they can be safely used in poultry feed.However,previous studies mainly focused on broiler feed,and there is currently no consensus on the optimal dosage and its effect on production performance.This study first drew on the application of meta-analysis techniques in the medical field to investigate the overall effectiveness of using edible mushroom materials in poultry feed by collecting relevant literature in the past 20 years.After screening,29 relevant studies were included in the metaanalysis.The analysis results showed that edible mushrooms can be safely used in poultry feed and have a growth-promoting effect(p<0.05).Subgroup analysis results showed that the growthpromoting effect of mixed waste utilization was better(p<0.05),while the growth-promoting effect of edible mushroom polysaccharides was not significant(p>0.05).Therefore,edible mushroom waste has high utilization value as feed,and its growth-promoting effect is the combined effect of multiple active substances.The results of the meta-analysis indicate the effectiveness of edible mushrooms in promoting poultry growth.However,as laying hens need to be fed for a long time,and their breeding cycle is long,the effects of mushroom materials on the growth,development,and egg production of laying hens at different stages have not been reported.Therefore,this study designed a long-term feeding trial to verify the effect of mushroom materials on laying hens at different developmental stages.The study selected 540 Isa Brown laying hens for long-term feeding trials and investigated the effects of FVS on various stages of the hens’ growth,development,and egg production.The experiment was divided into five treatment groups: blank control group,antibiotic group,and three FVS groups with different dosages(2%,4%,and 6%).The effects of FVS on the growth and development,production performance,and lipid metabolism of laying hens were studied.The results showed that the addition of 2% FVS significantly reduced the average daily weight gain of laying hens during the chickrearing period,affecting their growth and development.Blood lipid tests also found a significant decrease in total triglycerides(TG)in the serum of the 2% added group.Therefore,adding 2% FVS will cause metabolic energy deficiency and slow growth and development of laying hens during the chick-rearing period.However,in long-term feeding,the addition of FVS at different dosages did not significantly affect the growth and development or egg production performance of laying hens.The body weight and FCR of the laying hens in the 2% FVS group before entering the egg-laying period were no longer different from those of other treatment groups.In addition,the FVS group before the chick-rearing period had a lower average daily feed intake(ADFI),but there was no significant difference in feed conversion rate(FCR).After the laying hens entered the egg-laying period,there was no significant difference in production performance indicators such as egg production rate and average egg weight among the treatment groups.The overall trend analysis showed that the addition of 4% and 6% FVS had better egg production performance.At the same time,the addition of 6% FVS significantly reduced the cholesterol content in the yolk before 28 weeks.However,this difference gradually decreased after28 weeks,and there was no difference between the treatment groups.This is related to the stability of the genetic material of the laying hens.There was also no significant difference in the flavor substances of eggs among the treatment groups,indicating that the addition of FVS did not significantly change the flavor substances of eggs.Long-term feeding of FVS and antibiotics will regulate the lipid metabolism level of laying hens to some extent,mainly manifested as the reduction of serum total cholesterol,LDL-C levels,and TG levels in the FVS-added group.However,there was no significant difference in serum HDLC levels among the treatment groups,indicating that FVS and antibiotics did not affect the level of good cholesterol in laying hens.The results of this study indicate that the addition of edible mushroom waste can improve the production performance and lipid metabolism of laying hens to a certain extent,without affecting the flavor substances of eggs.For the issue of data format differences found in meta-analysis over the years,as well as the standardization of descriptions of a large number of inter group differences found in the processing of experimental data for laying hens.This study proposes a theoretical model of a "research data standardization platform system" centered on data.Through the construction of this platform,the differentiation problem of homogenized data in the application research of active substances in edible mushroom crops and plants can be solved in every step from method description to measurement and analysis.In summary,this study confirmed the growth-promoting effect of edible mushrooms on poultry.Additionally,long-term trials were conducted on Isa Brown laying hens to investigate the impact of FVS on their growth,development,and egg production at different stages,as well as the appropriate dosage for adding FVS.The study also explored the effect and mechanism of FVS on lipid metabolism in laying hens and proposed a theoretical model suitable for data analysis in similar research.