Influences of immersion bathing in Bacillus velezensis DY-6 on growth performance,non-specific immune enzyme activities and gut microbiota of Apostichopus japonicus

In this study, the influences of immersion bathing in different concentrations of Bacillus velezensis DY-6 on the body weight gain rate and non-specific immune enzyme activities of the coelom fluid of sea cucumber (Apostichopus japonicus) were determined in order to obtain the optimum bacterial concentration. The gut microbiota change in A. japonicus was then analyzed through high-throughput sequencing during the immersion bathing in B. velezensis DY-6 at the optimum concentration for 49 d. The results illustrate that the body weight growth rate of all bathing groups was higher than that of the control. The highest growth rate (25.3%) was achieved when the bacterial concentration was 1×10^3 CFU/mL. The activities of non-specific immune enzymes (ACP, AKP, SOD and LZM) of all bathing groups increased, and the activities of the enzymes of groups bathed with the bacterium at 1×10^3 and 1×10^4 CFU/mL reached the highest on day 21 and day 28. Taking the growth rate and economic cost into consideration, the optimum concentration of B. velezensis DY-6 was 1×10^3 CFU/mL. The influences of immersion bathing in B. velezensis DY-6 at 1×10^3 CFU/mL on the gut microbiota of A. japonicus were then evaluated through 16S rDNA sequencing analysis. Results showed that the gut microbiota changed with the addition of B. velezensis DY-6, and the richness and diversity of the gut microbiota peaked twice on day 14 and day 21, respectively. In association with the non-specific immune enzyme activities and if day 28 was selected as the dividing point, the community structure of the gut microbiota could be obviously divided into two types. The correlation analysis revealed that the non-specific immune enzyme activities were correlated significantly to some gut bacteria (in the phyla Firmicutes, Proteobacteria, and Bacteroidetes) after immersion bathing in B. velezensis DY-6. Our findings will provide the theoretical foundation for probiotic application in sea cucumber farming.

Effects of dietary supplementation of probiotic,Clostridium butyricum,on growth performance,immune response,intestinal barrier function,and digestive enzyme activity in broiler chickens challenged with Escherichia coli K88

Background： Colibacillosis caused by enterotoxigenic Escherichia coil （E. coil} results in economic losses in the poultry industry. Antibiotics are usually used to control colibacillosis, however, E. coli has varying degrees of resistance to different antibiotics. Therefore the use of probiotics is becoming accepted as an alternative to antibiotics. In this study, we evaluated the effects of Clostfidium butyricum （C. butyficum） on growth performance, immune response, intestinal barrier function, and digestive enzyme activity in broiler chickens challenged with Eschefichia coli （E. coil） K88. Methods： The chickens were randomly divided into four treatment groups for 28 days. Negative control treatment （NC） consisted of birds fed a basal diet without E. coil K88 challenge and positive control treatment （PC） consisted of birds fed a basal diet and challenged with E. coil K88. C. buO/ricum probiotic treatment （CB） consisted of birds fed a diet containing 2 x 107 cfu C. buO/ricum/kg of diet and challenged with E. coil K88. Colistin sulfate antibiotic treatment （CS） consisted of birds fed a diet containing 20 mg colistin sulfate/kg of diet and challenged with E. coil K88. Results： The body weight （BW） and average day gain （ADG） in the broilers of CB group were higher （P 〈 0.05） than the broilers in the PC group overall except the ADG in the 14-21 d post-challenge. The birds in CB treatment had higher （P 〈 0.05） concentration of tumor necrosis factor-a （TNF-a） at 3 and 7 d post-challenge, and higher （P 〈 0.05） concentration of interleukin-4 （IL-4） at 14 d post-challenge than those in the PC treatment group. The concentration of serum endotoxin in CB birds was lower （P 〈 0.05） at 21 d post-challenge, and the concentrations of serum diamine oxidase in CB birds were lower （P 〈 0.05） at 14 and 21 d post-challenge than in PC birds. Birds in CB treatment group had higher （P 〈 0.05） jejunum villi height than those in PC, NC, or CS treatment at 7, 14, and 21 d post-challenge. In comparison to PC birds, the CB birds had lower （P 〈 0.05） jejunum crypt depth during the whole experiment. The birds in CB or CS treatment group had higher （P 〈 0.05） activities of amylase and protease at 3, 7, and 14 d post-challenge, and higher （P 〈 0.05） activity of lipase at 3, 7 d post-challenge than PC birds.

Ubiquitin-conjugating enzyme involved in the immune response caused by pathogens invasion

Ubiquitin-proteasome pathway (UPP) is a significant way of protein degradation and modification in eukaryotic cell and involved in a complex series of intracellular processes. As a key component in UPP,?ubiquitin-conjugating enzyme (E2) plays an extremely important role in ubiquitin (Ub) transferring and substrate specific recognition. Abundant evidences have proved that UPP is involved in cells immune reaction caused by pathogens and the attendance of E2 has a significant effect on host cells and pathogen. This article presents an overview of the current research on E2s that is involved in immune response caused by viruses and bacteria.

Effects of Pseudoalteromonas sp. BC228 on Digestive Enzyme Activity and Immune Response of Juvenile Sea Cucumber(Apostichopus japonicus)

A marine bacterium, Pseudoalteromonas sp. BC228 was supplemented to feed in a feeding experiment aiming to determine its ability of enhancing the digestive enzyme activity and immune response of juvenile Apostichopus japonicus. Sea cucumber individuals were fed with the diets containing 0(control), 105, 107 and 109 CFU g-1 diet of BC228 for 45 days. Results showed that intestinal trypsin and lipase activities were significantly enhanced by 107 and 109 CFU g-1 diet of BC228 in comparison with control(P < 0.01). The phagocytic activity in the coelomocytes of sea cucumber fed the diet supplemented with 107 CFU g-1 diet of BC228 was significantly higher than that of those fed control diet(P < 0.05). In addition, 105 and 107 CFU g-1 diet of BC228 significantly enhanced lysozyme and phenoloxidase activities in the coelomic fluid of sea cucumber, respectively, in comparison with other diets(P < 0.01). Sea cucumbers, 10 each diet, were challenged with Vibrio splendidus NB13 after 45 days of feeding. It was found that the cumulative incidence and mortality of sea cucumber fed with BC228 containing diets were lower than those of animals fed control diet. Our findings evidenced that BC228 supplemented in diets improved the digestive enzyme activity of juvenile sea cucumber, stimulated its immune response and enhanced its resistance to the infection of V. splendidus.

Short-term effect of supplemental yeast extract without or with feed enzymes on growth performance, immune status and gut structure of weaned pigs challenged with Escherichia coli lipopolysaccharide

Background： This study investigated the response of piglets receiving a yeast extract without or with a multi-enzyme mixture compared with an antimicrobial growth promoter（AGP） on performance, immune status and gut structure after an E. coli lipopolysaccharide（LPS） challenge. Thirty-six pigs were allotted to six treatments including： a non-challenged control（NCC）; LPS-challenged control（CC）; CC ＋ AGP; CC ＋ yeast extract; CC ＋ enzymes; and CC ＋ enzymes ＋ yeast extract. On d 7, pigs were bled and thereafter injected with LPS or sterile saline. Blood samples were collected at 6, 48, and 96 h post-challenge. After 96 h post-challenge, pigs were euthanized to obtain duodenal, jejunal and ileal samples.Results： Overall（d 1 to 11）, compared with CC pigs, AGP attenuated the LPS-induced reduction in ADG（P = 0.004）,ADFI（P = 0.03） and gain/feed ratio（P = 0.01）. At 6 h post-challenge, AGP pigs had lower plasma urea N（PUN; P = 0.02）and serum TNF-α concentration（P = 0.07）, and higher platelet count（P = 0.04） and serum IL-10 concentration（P = 0.02） than CC pigs. At 48 h post-challenge, AGP pigs had lower PUN（P = 0.02） than CC pigs, whereas enzymes ＋ yeast extract interacted non-additively（P = 0.001） to reduce PUN. At 96 h post-challenge, AGP pigs had lower PUN（P = 0.02）and higher duodenal（P = 0.03）, jejunal（P = 0.01） and ileal（P = 0.07） villus height than CC pigs. In addition, enzymes ＋yeast extract interacted additively and non-additively to reduce ileal IFN-γ（P 0.10） were observed between AGP and enzymes ＋ yeast extract pigs on other measured parameters except for the downregulation of ileal IFN-γ（P ＆lt; 0.0001） and TNF-α（P = 0.003） in enzymes ＋ yeast extract pigs at 96 h post-challenge.Conclusions： The LPS challenged piglets receiving enzymes ＋ yeast extract showed beneficial responses in gut structure and immunity commensurate with those receiving antibiotics, though the latter had better overall growth performance.

Effect of ursodeoxycholic acid combined with bifidobacterium quadruple preparations on myocardial enzyme, immune function and inflammatory response of hyperbilirubinemia neonatal

Objective: To investigate the effects of myocardial enzyme, immune function and inflammatory response by ursodeoxycholic acid combined with bifidobacterium quadruple preparations on hyperbilirubinemia neonatal. Methods: A total of 100 cases of neonatal hyperbilirubinemia in our hospital from June 2016 to May-2017 were selected and divided into control group and observation group by random number table, 50 cases in each group. Two groups of neonatal were given routine symptomatic treatment. The control group was treated with ursodeoxycholic acid and the observation group was treated with Bifidobacterium tetralogy of live bacteria on the basis of the control group. The two groups of neonatal were both treated for 7 d. The serum levels of CK-MB, CK, LDH, AST, CD3+, CD4+, CD4+/CD8+, CD8+, CRP and TNF-α were measured before and after the treatment of the two groups. Results: Before treatment, there was no significant difference in serum CK-MB, CK, LDH, AST, CD3+, CD4+, CD4+/CD8+, CD8+, CRP and TNF-α levels between the 2 groups. After treatment: 2 groups of serum CK-MB, CK, LDH, AST, CD8+, CRP, TNF-α levels significantly decreased compared with the group before treatment, CD3+, CD4+ and CD4+/CD8+ levels were significantly increased after treatment, and the observation group with serum CK-MB, CK, LDH, AST, CD8 +, CRP, TNF-α levels were significantly lower than the control group, CD3+, CD4+ and CD4+/CD8+ levels were significantly higher than the control group, the differences were statistically significant. Conclusion: Ursodeoxycholic acid combined with Bifidobacterium quadruple viable tablets can can reduce the activity of myocardial enzyme, improve the state of spectrum index of neonatal hyperbilirubinemia.

Seawater acidification affects the immune enzyme activities of the Manila clam Ruditapes philippinarum

Ocean acidification leads to changes in physiological and immune responses of bivalves, but the eff ect on the immune enzyme activities of the Manila clam, R uditapes philippinarum, when the pH is lower than the normal value has not been studied in detail. In this study, experiments were conducted to determine how pH(7.4, 7.7, 8.0) affects the immune enzyme activities in the gill and hemocytes of the Manila clam. Membrane stability and phagocytosis increased with decrease of pH from 8.0 to 7.7 and then decreased at pH 7.4. The total protein content in the hemocytes and gills decreased with decreasing pH. Lysozyme content in the hemocytes increased with decreasing pH, and the diff erences were significant among the different pH groups(P < 0.05). Adenosine triphosphatase activity at pH 7.4 was significantly higher than in the other two groups, but no significant diff erence was observed between pH 7.7 and 8.0. Catalase activity decreased from pH 8.0 to 7.7 and then increased at pH 7.4, and the dif ferences were significant among the experimental groups( P < 0.05). These findings provide valuable information about the immune response of R. philippinarum to reduced water pH and insights for future research investigating exposure of bivalves to elevated CO_2 conditions.

Effects of Size Grading on Growth and Non-Specific Immunity Factors of the Shrimp Litopenaeus vannamei Boone

The study aims to determine the effects of graded farming on growth performance and non-specific immunity factors of shrimp Litopenaeus vannamei Boone. Three size groups of shrimp, i.e., the small size group [Gs, with an average body length （BL） of （3.04 ± 0.36） cm and body weight （BW） （0.412± 0.35） g], the large group [GL, with a BL of （4.29±0.55） cm and BW of （1.098 ±0.42） g], and the ungraded group [Gm, with a BL of （3.47±0.81） cm and BW of （0.611 ±0.79） g], were reared under the same conditions for 8 wk. Growth performance and non- specific immunity factors were measured. The results showed that BW gain, biomass gain and the specific growth rate of body length （SGRL） were significantly influenced by size grading （one-way ANOVA, P 〈 0.05）. The peroxidase （POD） and antibacterial （Ua） activities of GL were lower than those of G. Superoxide dismutase （SOD） and lysozyme （U1） activities of Gm were lower than those of G. No significant difference （P = 0.121 〉 0.05） was found on phenoloxidase （PO） activity among the three size groups. Synthetically, size grading could enhance growth and rearing efficiency, and did not have a significant influence on the immunity of L. vannamei Boone. Therefore, graded fanning in L. vannamei Boone was feasible in the culture practice.

High Level of Ubiquitin Conjugate Enzyme E2O Indicates Poor Prognosis of Patients with Hepatocellular Carcinoma

Objective Ubiquitin conjugate enzyme E2O(UBE2O)is a ubiquitin-conjugating enzyme that has been reported to be involved in tumorigenesis.This study investigated the role of UBE2O in hepatocellular carcinoma(HCC).Methods The expression of UBE2O was detected using qRT-PCR,Western blotting,and immunohistochemical staining.Cell proliferation and Transwell assays were used to detect proliferation,migration,and invasion of HCC cells,respectively.Bioinformatic analysis was performed to analyze the relationship between UBE2O and the clinical features,prognosis,and immune cell infiltration of HCC.Results UBE2O was significantly over-expressed in HCC tissues.High expression of UBE2O was associated with poor tumor grade and poor prognosis.Functional experiments showed that down-regulation of UBE2O inhibited HCC cell proliferation,migration,and invasion.Co-expression gene analysis and gene set enrichment analysis showed that UBE2O was associated with protein hydrolysis,cell cycle,and cancer-related pathways in HCC.The results of immune analysis revealed that the expression of UBE2O was positively correlated with the immune infiltration and expression of immune-related chemokines of HCC.Conclusions UBE2O is significantly correlated with the prognosis of HCC and may be a valuable prognostic biomarker for HCC.

Effects of the Chinese Medicinal Herb Com plex Additives on Non-specific Immunity of Amursturgeon( Acipenser schrencki Brandt)

This study was to investigate the effects of aqueous decotion from three Chinese medicinal herb additives （ Cyrtomium fortunei, prescription I and prescription II） on non-specific immunity of 1 ＋ age old Amur sturgeon （Acipenser schrencki Brandt） by oral perfusion. Cyrtomiumfortunei, prescription I and prescription II were orally given to 15 fishes for each experimental group once a day, with the concentration of 9,175 and 36 g/S0 kg body weight, respectively. The administration was lasted for 14 days. Meanwhile, distilled water was orally given as the control. After the experiment, some of the experimental fishes were stimulated with high temperature （30 ℃ ） for two hours. Sampling was performed from fishes treated at 22 ℃ and 30 ℃ for measuring the protein content in the serum, phagocytic activity of leucocytes and the activity of the lysozyme in six tissues. The results indicated that Cyrtomiumfortunei and prescription II could help to enhance the content of various proteins and the phagocytic activity of leucocytes. There was no significant change in the effects between these two additives at either the normal temperature or high temperature. Prescription I did not show an obvious effect on the immunity of fishes at the normal temperature, but it did in promo- ting high-efficiency response and improving immunoregulation of fish shocked by some stimuli.

Effect of Dietary Alanyl-glutamine Supplementation on Growth Performance, Development of Intestinal Tract, Antioxidant Status and Plasma Non-specific Immunity of Young Mirror Carp(Cyprinus carpio L.)

Exogenous alanyl-glutamine（Aln-Gln） was evaluated for its effects on growth performance, intestinal structure and function, antioxidant status and non-specific immunity of young carp（Cyprinus carpio L.）. Six diets supplemented with 0, 2.5, 5.0, 7.5, 10.0, or 15.0 g · kg-1 of Aln-Gln were fed to fish for 12 weeks. Supplementation with 7.5, 10.0, or 15.0 g · kg-1 of Aln-Gln significantly increased weight gain rate（WGR）, protein efficiency ratio（PER）, but feed conservation rate（FCR） and survival were not affected（P〉0.05）. The intestinal fold height and number, digestive enzyme, Na＋, K＋-ATPase activities was found to be significantly high（P〈0.05） with increasing dietary Aln-Gln supplementation up to 7.5 g · kg-1, but there were no significant differences for Aln-Gln supplementation from 7.5 to 15.0 g · kg-1. The glutathione peroxidase（GPX） activity, glutathione（GSH）, superoxide dismutase（SOD） activity increased and malondialdehyde（MDA） levels decreased significantly（P〈0.05） in the intestine, hepatopancreas, plasma and muscles. The plasma complement-3（C3） and complement-4（C4） levels were significantly（P〈0.05） improved at 5.0 g · kg-1 level and decreased when over 7.5 g · kg-1. The plasma lysozyme（LSZ） activity increased significantly（P〈0.05） at 7.5, 10.0, or 15.0 g · kg-1 level. In summary, the results showed that Aln-Gln improved growth performance, development and function of the intestine, the activity of the antioxidant defense system and the plasma non-specific immunity of the carps. The optimal Aln-Gln level was 8.24 g · kg-1 diet for WGR based on broken-line regression model analysis.

Growth performance,digestive enzyme activities and serum nonspecific immunity of the red tilapia(Oreochromis mossambicus×Oreochromis niloticus)feddiets supplemented with ultrafine powder of Enteromopha prolifera

The present study evaluated ef fects of ultrafine powder of the green macroalgae E nteromopha prolifera as dietary supplement on growth performance, digestive enzyme activities and serum nonspecific immune responses of the red tilapia(O reochromis mossambicus × Oreochromis niloticus). The red tilapia were fed five diets supplemented with different levels of E. prolifera ultrafine powder as well as a control diet containing no E. prolifera for seven weeks(Diets 0–6 contained 0(control), 10, 20, 30, 40 and 50 g/kg of E. prolifera ultrafine powder, respectively). The results showed that diets supplemented with E. prolifera ultrafine powder generally improved growth, immunity and digestive enzyme activities of the red tilapia. In particular, the fish fed the diet incorporated 50 g/kg (5%) E. prolifera ultrafine powder(Diet 5) achieved the highest percentage weight gain, specific growth rate and the condition factor(increased by 15.4%, 8.0% and 5.7%, respectively when compared to the control). Feeding the diet also led to significantly increases( P <0.05) in serum nonspecific immune responses, including total superoxide dismutase, acid phosphatase, alkaline phosphatase, lysozyme activities and serum total protein(increased by 19.4%, 48.1%, 29.5%, 30.3% and 8.7%, respectively) as well as digestive enzyme activities of erepsin, gastric amylase, gastric lipase, pepsin, intestinal amylase and gastric lipase(increased by 15.7%, 33.3%, 16.3%, 21.3%, 52.3% and 28.2%, respectively) than those of the control. Based on these results, it is recommended that the inclusion level of E. prolifera ultrafine powder in the diet of the red tilapia should be 50 g/kg(or 5%).

Effect of Ammonia-Nitrogen Stress on Non-specific Immunity of Hybrid Tilapia(Oreochromis niloticus× Oreochromis areus)

The juveniles of hybrid tilapia （ Oreochromis niloticus x Oreochromis areus） were exposed to ananonia-nitrogen （N） （0, 2.5, 5, 10 and 20 mg/L） for 0, 12, 24, 48 and 72 h to evaluate the effect of ammonia-N stress on their non-specific immunity. Results show that the activity of serum lysozyme decreased signifi- candy with extension of stress time （P 〈 0.05）. The total antioxidant capacity （T-AOC） and activity of antioxidase in liver were significantly affected. The activi- ty of T-AOC and total superoxide dismutase （T-SOD） of fish exposed to ammonia-N were initially decreasing then increasing （ P 〈 0.05 ）. Activities of catalase （CAT） and glutathione peroxidase （GSH-Px） were correlated with concentrations of ammonia-N. Fish exposed to lower concentrations （2.5 mg/L or 5 mg/L） showed decreased CAT activity within 24 h （P 〈 0.05 ）, while those exposed to higher concentrations （10 mg/L or 20 mg/L） initially showed increased then decreased activity of CAT. Except for the highest concentration groups, fish exposed to ammonia-N showed inductive activity of GSH-Px （ P 〈 0.05 ）. Under the ex- perimental conditions, non-specific immunity of tilapia was affected by ammonia-N stress, and the impact was increased with increased concentration and extension of time.

Angiotensin-converting enzyme 2 connects COVID-19 with cancer and cancer immunotherapy

The coronavirus disease 2019(COVID-19)pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has resulted in more than two million deaths.Underlying diseases,including cancer,are high-risk factors for severe COVID-19 outcomes.Angiotensin-converting enzyme 2(ACE2),as a SARS-CoV-2 host cell receptor,plays a crucial role in SARS-CoV-2 invading human cells.ACE2 also has significant associations with cancer.Recent studies showed that ACE2 was inversely correlated with the activities of multiple oncogenic pathways and tumor progression phenotypes,and was positively correlated with antitumor immune response and survival prognosis in diverse cancers,suggesting a potential protective role of ACE2 in cancer progression.Positive expression of ACE2 is also correlated with programmed death-ligand 1(PD-L1)in cancer.The positive associations of ACE2 expression with antitumor immune signatures and PD-L1 expression indicate that ACE2 expression is a positive predictor for the response to immune checkpoint inhibitors(ICIs).This was evidenced in multiple cancer cohorts treated with ICIs.Thus,ACE2 may build potential connections between COVID-19 and cancer and cancer immunotherapy.The potential connections suggest that ACE2 inhibitors may not be a good option for treating COVID-19 patients with cancer,particularly in cancer patients who are receiving immunotherapy.Furthermore,the relationships between ACE2,COVID-19,and cancer are worth confirming by more experimental and clinical data,considering that many cancer patients are at high risk for COVID-19.

Effects of Methionine on the Immune Function in Animals

Nutrition and immunity are the hot topics in animal’s production, and the effects of methionine on the immunity are already confirmed as the deep research on the nutrition of amino acid and immune function. However, the relationship of the methionine and immunity has not been elucidated clearly, this review aims to clarify the effects of methionine on immune function in the aspects of growth and development immune organs, the histological structure of the immune organs, non-specific immunity, humoral immunity, cellular immunity and cytokines, and to provide foundations for further studies on the relationship between methionine and immune function.

复方中草药对小丑鱼非特异性免疫、消化酶活性的影响及对刺激隐核虫杀灭效果分析

刺激隐核虫寄生感染引起的“白点病”不仅危害水族箱观赏鱼类,还会对水族馆大水体海水观赏鱼带来毁灭性打击,是海水观赏鱼养殖业危害最为严重的病害之一。本研究探讨了在基础饲料中添加不同剂量复方中草药“XCY-1”(苦参、地肤子、蛇床子、黄芪、甘草等按一定比例混合,超微粉碎后收集备用)对小丑鱼血清、肝脏中非特异性免疫指标和肠道消化酶活性指标变化及不同用药方式对防治刺激隐核虫病的效果。研究结果显示,投喂复方中草药“XCY-1”可使小丑鱼血清中溶菌酶(LZM)、超氧化物歧化酶(SOD)、碱性磷酸酶(AKP)、酸性磷酸酶(ACP),肝脏中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)、过氧化氢酶(CAT)、总抗氧化能力(T-AOC)活性均呈现先升后降趋势,第21 d各项非特异性免疫指标达到最高值,其中20 g/kg剂量组效果最好,能显著提高小丑鱼的免疫能力;肠道中淀粉酶(AMS)、脂肪酶(LPS)和胰蛋白酶在各取样点活性均高于对照组,20 g/kg剂量组在各取样点胰蛋白酶和AMS活性高于其他剂量组,20 g/kg和40 g/kg剂量组在各取样点LPS活性最高。复方中草药“XCY-1”药浴对刺激隐核虫幼虫的体外杀灭结果显示:4 h内,50 mg/L药物浓度即对刺激隐核虫幼虫具有一定的杀灭效果,400 mg/L药物浓度即可杀灭全部幼虫;当药物浓度达到800 mg/L时,3 h内幼虫全部死亡。不同用药方式防治小丑鱼刺激隐核虫病:实验分为4组,A组20 g/kg剂量组,口服无药浴;B组20 g/kg剂量组,口服且同时按50 mg/L进行药浴;C组20 g/kg剂量组,口服且同时按100 mg/L进行药浴;D组为对照组,仅投喂基础饲料。结果显示:实验第6 d,A、B、C三个药物组与对照组的存活率分别为:51.1%、53.3%、57.7%、0,药物组存活率显著高于对照组(P<0.05);三个药物处理组每片鳃上仅有0~2个滋养体,对照组每片鳃上滋养体数量是用药组65倍。综上所述,饲料中添加复方中草药“XCY-1”可以提升小丑鱼血清、肝脏非特异性免疫指标和肠道消化酶活性,对刺激隐核虫病起到积极的预防和治疗效果。20 g/kg剂量组、投喂时间14~21 d时效果最佳。该研究为开发无公害、环保型天然植物源杀虫药提供理论参考和技术支撑。

乳酸菌和抗生素对中华蜜蜂肠道消化酶活性、免疫基因表达及工蜂存活率的影响

本试验旨在通过在中华蜜蜂糖饲料中添加乳酸菌和抗生素,评价二者对中华蜜蜂肠道消化酶活性、免疫基因表达及工蜂存活率的影响,为其在蜜蜂养殖中的应用提供依据。试验选取0日龄的中华蜜蜂工蜂540只,随机分为3个组,每组3个重复,每个重复60只蜜蜂。对照组饲喂50%(质量分数,下同)蔗糖溶液,试验组分别饲喂添加1×108 CFU/mL植物乳杆菌的50%蔗糖溶液(乳酸菌组)和添加450μg/mL四环素的50%蔗糖溶液(抗生素组)。于15日龄,测定中肠消化酶活性和免疫基因相对表达量;于30日龄,测算工蜂存活率。结果表明:1)与对照组相比,乳酸菌组中华蜜蜂中肠淀粉酶活性显著提高(P<0.05),中肠Abaecin、Toll基因的相对表达量显著提高(P<0.05),中肠Cactus-1基因的相对表达量显著降低(P<0.05),工蜂的平均生存时间显著延长2.75 d(P<0.05)。2)与对照组相比,抗生素组中华蜜蜂中肠淀粉酶和蛋白酶活性均显著降低(P<0.05),中肠防御素-1(Defensin-1)、肽聚糖识别蛋白(PGRP)和Cactus-1基因的相对表达量显著降低(P<0.05),工蜂的平均生存时间显著缩短2.39 d(P<0.05)。由此可知,饲喂乳酸菌可提高中华蜜蜂肠道消化酶活性,增强肠道免疫功能,提高工蜂存活率;饲喂抗生素可降低中华蜜蜂肠道消化酶活性,降低工蜂存活率。

两种不同免疫检验方法检测乙型肝炎病毒感染血清学标志物的临床疗效

目的分析两种不同免疫检验方法检测乙型肝炎病毒感染血清学标志物的临床疗效。方法回顾性分析2021年6月至2022年6月枣庄市立医院收治的88例乙型肝炎患者的临床资料,所有患者均确诊为乙型肝炎病毒感染,并采用磁微粒化学发光法、酶联免疫吸附法检测乙型肝炎病毒感染血清学标志物。比较两种免疫检测方法对乙型肝炎病毒感染血清学标志物的检出情况和诊断准确率。结果磁微粒化学发光法对乙型肝炎病毒表面抗原、乙型肝炎病毒e抗原、乙型肝炎病毒e抗体的阳性检出率高于酶联免疫吸附法,差异有统计学意义(P<0.05);两种免疫检验方法对乙型肝炎病毒表面抗体、乙型肝炎病毒核心抗体的阳性检出率比较差异无统计学意义。磁微粒化学发光法对乙型肝炎表面抗原浓度≤0.50 IU/ml的检出率高于酶联免疫吸附法,差异有统计学意义(P<0.05)。磁微粒化学发光法对乙型肝炎病毒感染诊断准确率高于酶联免疫吸附法,差异有统计学意义(P<0.05)。结论采用电化学发光法可提高乙型肝炎病毒血清学标志物的检验准确率,为临床筛查乙型肝炎病毒感染提供有力支持。

氨氮短期胁迫与恢复对克氏原螯虾的影响

为探究氨氮胁迫与恢复对克氏原螯虾抗氧化和免疫酶活性及组织结构的影响,将体质量(6.33±0.73)g的克氏原螯虾暴露于0、20、40、60、80 mg/L 5个氨氮质量浓度下,比较胁迫48 h时及恢复48 h后,各组肝胰腺、鳃和血清的抗氧化和免疫酶活性以及各组肝胰腺和肌肉组织结构的变化。试验结果显示:氨氮对克氏原螯虾幼虾24、48、72、96 h的半致死质量浓度分别为359.37、238.09、196.34、162.00 mg/L,安全质量浓度为16.20 mg/L。胁迫48 h后,除20 mg/L试验组外,其余试验组肝胰腺的总超氧化物歧化酶活性较对照组显著增强,80 mg/L组鳃的总抗氧化能力显著降低、过氧化氢酶活性显著增强,80 mg/L组血清的总超氧化物歧化酶活性显著增强;恢复48 h后,60 mg/L组肝胰腺和鳃的丙二醛含量较对照组显著上升,80 mg/L组鳃的过氧化氢酶活性较对照组显著增强,60 mg/L组血清的总抗氧化能力较对照组显著上升,其他试验组酶活性均恢复至对照组水平。氨氮胁迫48 h,随着氨氮质量浓度的升高,肝胰腺管腔逐渐变形、转运泡增大,鳃的呼吸上皮细胞开始脱落、微血管腔受损;恢复48 h后,肝胰腺的组织结构基本恢复正常,40、60、80 mg/L组鳃局部呼吸上皮细胞脱落,微血管腔受损。试验结果表明,20 mg/L质量浓度的氨氮胁迫48 h即会对克氏原螯虾抗氧化和免疫酶及组织结构造成损伤,解除胁迫48 h后可得到修复。克氏原螯虾经40、60、80 mg/L质量浓度的氨氮胁迫48 h后恢复48 h,鳃仍处于应激状态。

酵母水解物对克氏原螯虾生长性能、消化、抗氧化和免疫能力的影响

实验研究了添加不同水平酵母水解物(Yeast hydrolysate,YHY)对克氏原螯虾(Procambarus clarkii)生长性能、消化、抗氧化和非特异性免疫能力的影响。实验选用300尾平均体重为(6.43±0.55)g的个体,随机分为5组,分别饲喂在基础饲料中添加0(对照组)、0.5%、1%、2%和4%YHY的饲料,每组3个重复,养殖密度为20尾/缸。为期8周的实验结束后,测定克氏原螯虾生长指标、胃和肝胰腺消化酶活性、肝胰腺抗氧化性能、血清生化指标和免疫酶活性。结果表明:(1)饲料中添加1%—4%YHY对该虾生长指标有促进作用。其中,2%添加组的存活率(SR)、最终体重(FBW)、最终体长(FBL)和肝胰腺指数(HSI)达最大值且显著高于对照组(P<0.05),增重率(WGR)和特定生长率(SGR)在1%添加组达到最大值且显著高于其余各组(P<0.05);(2)1%YHY添加组的全虾粗蛋白质含量显著高于其他组(P<0.05),而肌肉粗蛋白和粗脂肪含量在2%添加组达到最大值;(3)与对照组相比,2%—4%YHY添加组的胃和肝胰脏消化酶活性显著提高(P<0.05);(4)2%YHY添加组的肝胰腺抗氧化酶(过氧化氢酶,CAT;总超氧化物歧化酶,T-SOD;总抗氧化能力,T-AOC)和免疫酶(碱性磷酸酶,AKP;酸性磷酸酶,ACP)的活性达到最大值、丙二醛(MDA)的含量达到最小值,且与对照组相比均有显著差异(P<0.05);(5)2%YHY添加组该虾血清中总蛋白(TP)和白蛋白(ALB)含量显著高于其他组(P<0.05),1%和2%YHY添加组谷丙转氨酶(ALT)和谷草转氨酶(AST)活性显著低于其他各组(P<0.05)。结果表明,饲料中添加2%的酵母水解物可显著提高克氏原螯虾的消化、生长及肌肉粗蛋白和粗脂肪含量,并显著改善其抗氧化和非特异性免疫能力。