Effect Of Photo Synthetic Bacteria Treatment Of Rearing Water On Hatching Performance And Health Status Of Geese

At present,the water surface culture of geese is still one of the main ways of geese production.In this mode of production,geese often discharge feces into the water,and the excretion will lead to the increase of organic matter content such as microorganisms,ammonia nitrogen and nitrite in the water.When geese drink the polluted water,they often endanger the health of geese and cause the decline of production performance.Therefore,in the process of water surface culture of geese,reducing water pollution has become one of the urgent problems to improve the production level of geese and the sustainable development of geese industry.Numerous studies have found that microbial agents can effectively reduce the concentration of harmful substances such as ammonia and phosphorus in farm water and manure,control the content of ammonia,nitrite and hydrogen sulfide,and maintain the stability of the ecosystem.As a low cost and high efficiency microbial agent with unique metabolism,photosynthetic bacteria can effectively remove ammonia,nitrogen and organic matter from aquaculture water,regulate the bacterial community structure of the water body,and thus purify the aquaculture water body.Therefore,treatment of aquaculture water by photosynthetic bacteria is the key to guarantee the hatching performance and health condition of breeding geese.Based on this,this experiment took Yangzhou goose breeding geese as the research object,and by adding photosynthetic bacteria to the aquaculture water,to explore the effect of photosynthetic bacteria on the hatching performance and health of breeding geese,and to add suitable probiotics to the aquaculture water in the future.Provide method guidance and theoretical basis for improving the health and hatching performance of breeding geese.（1）Effect of photosynthetic bacteria treatment of aquaculture water on hatching performance,serum biochemical indexes,and water purification effect of breeding geese:To investigate the effect of photosynthetic bacteria treatment of aquaculture water on the hatching performance of breeding geese,the health level of breeding geese and water purification efficiency,photosynthetic bacteria were added to the aquaculture water and the water was replaced every 10 d.Six batches were tested continuously.The results showed that the fertilization rate and hatching rate of fertilized eggs of breeding geese treated with photosynthetic bacteria in the first day of water exchange reached:91.83%and 91.34%respectively;the fertilization rate and hatching rate of fertilized eggs of breeding geese treated with photosynthetic bacteria in the 10th day of water exchange reached:92.17%and 93.15%respectively.The hatching rate of fertilized eggs was significantly higher than that of the control group（P<0.05）;the serum uric acid（UA）level of breeding geese in photosynthetic bacteria-treated water bodies was significantly lower compared with that of the control group（P<0.05）.The E.coli content、Salmonella content in the aquaculture water was highly significantly reduced（P<0.01）.（2）Inhibition of harmful bacteria in the water column by photosynthetic bacteria treatment and the effect on colonization in breeding geese:In order to find out the inhibitory effect of photosynthetic bacteria on harmful bacteria in aquaculture water and the effect on the colonization of breeding geese,The 16S rRNA high-throughput sequencing technology was used to analyze the microbial composition of the water affected by the time,the aquaculture water before and after photosynthetic bacteria treatment,the cecum of the geese and the allantoic fluid of the 16-day dead embryos.The results showed that the Alpha diversity of aquaculture water increased significantly with the extension of time.Bacteroidota,Patescibacteria,Campilobacterota,Fusobacteriota,Fibrobacterota,Gemmatimonadota,6 phyla were significantly increased（P<0.01）;Flavobacteriaceae,Comamonadaceae,Paludibacteraceae,Aeromonadaceae,Erysipelotrichaceae,Clostridiaceae,Bacteroidaceae,7 families were significantly increased（P<0.01）;Flavobacterium,Paludibacter,Aeromonas,Hydrogenophaga,Jeotgalibaca,Limnohabitans and Malikia 7 genus were significantly increased（P<0.01）.After the 10th d of treatment of aquaculture water with photosynthetic bacteria,the Alpha diversity of aquaculture water decreased significantly compared with the control group.Bacteroidota and Flavobacteriaceae,Moraxellaceae,Paludibacteraceae,Bacteroidaceae,norank_oPeptostreptococcales-Tissierellales,Clostridiaceae 6 families of flora were significantly reduced（P<0.01）;Psychrobacter,Flavobacterium,Paludibacter,Gottschalkia,Acinetobacter,Bacteroides,Aeromonas,Hydrogenophaga and Jeotgalibaca 9 genera were significantly reduced（P<0.01）.It can be seen from the above that photosynthetic bacteria can effectively prevent the growth of Flavobacterium,Paludibacter,Aeromonas,Hydrogenophaga and Acinetobacter in aquaculture water.Further analysis of the goose cecum and allantoic fluid of dead embryos showed that Campilobacterota,Acinetobacter,Dialister,Alloprevotella and other flora colonized in vivo.The traceability analysis found that there were 16 kinds of microbial flora in the aquaculture water,the cecum of the breeding goose and the allantoic fluid of dead embryos.There were 9 kinds of microbial flora that increased synchronously,including Akkermansia,Christensenellaceae_R-7_group,Pseudomonas and other genera;7 kinds that decreased synchronously,including Alistipes,Olsenella,Acinetobacter and other genera,most of which are potential pathogenic flora.In conclusion,using photosynthetic bacteria to treat aquaculture water has a positive effect.Photosynthetic bacteria can improve the structure of cecum flora and dead embryo allantoic fluid flora of aquaculture water,experimental geese,and improve the health and hatching performance of geese.At the same time,through the traceability analysis of water and cecum and dead embryo allantoic fluid of geese,potential pathogenic bacteria such as Alistipes,Olsenella,and Acinetobacter may pose a certain risk to the health and hatching performance of geese.