A novel apidaecin Api-PR19 synergizes with the gut microbial community to maintain intestinal health and promote growth performance of broilers

Background: Antibiotic growth promoters(AGPs) have been used as growth promoters to maintain animal intestinal health and improve feed efficiency in broilers by inhibiting pathogen proliferation. In view of the growing emergence of antibiotic-resistant pathogen strains and drug residue issues, novel treatments are increasingly required. This study aimed to compare two antimicrobial approaches for managing pathogen infection and maintaining animal intestinal health in broilers by supplying Apidaecin Api-PR19 and AGPs over 42 d of a feeding trial.Results: Compared with the broilers that were only fed a corn-soybean basal diet(CON group), supplementation with Api-PR19 and AGP(respectively named the ABP and AGP groups) both increased the feed conversion efficiency. When compared with the AGP group, Api-PR19 supplementation could significantly increase the organ index of the bursa of fabricius and subtype H9 antibody level in broiler chickens. Moreover, when compared with the CON group, the intestinal villus height, intestinal nutrient transport, and intestinal s Ig A content were all increased in the Api-PR19 group, while AGP supplementation was harmful to the intestinal villus height and intestinal nutrient transport. By assessing the antibacterial effect of Api-PR19 and antibiotics in vitro and in vivo, we found that Api-PR19 and antibiotics both inhibited the growth of pathogens, including Escherichia coli and Campylobacter jejuni. Furthermore, by using 16 S r RNA gene sequencing, the beneficial bacteria and microbiota in broilers were not disturbed but improved by apidaecin Api-PR19, including the genera of Eubacterium and Christensenella and the species of uncultured_Eubacterium_sp, Clostridium_asparagiforme, and uncultured_Christensenella_sp, which were positively related to improved intestinal development, absorption, and immune function.Conclusion: Apidaecin Api-PR19 treatment could combat pathogen infection and had little negative impact on beneficial bacteria in the gut compared to antibiotic treatment, subsequently improving intestinal development,absorption, and immune function.

Optimization of Extraction Technology for Rice Bran Oil

[ Objective ] This study aimed to optimize the extraction technology for rice bran oil. [ Method ] Using rice bran as raw material, effects of ultrasonicassisted extraction technology and different organic solvents, extraction durations, solid-liquid ratios and extraction temperatures on extraction results of rice bran oil were investigated. Based on the results of single-factor experiment, L9 （34 ） orthngonal experiment with three factors at three levels was conducted to optimize the extraction technological parameters, thus obtaining the optimal technological conditions for extracting rice bran oil. [ Result] Anhydrous ethanol led to the best extraction result; after ultrasonic treatment, the extraction rate of rice bran oil from raw material was not enhanced. The optimized technological parameters were ： extraction temperature of 80 ℃, extraction duration of 20 rain and solid-liquid ratio of 1：24 （ g： ml）. Under the optimized technological conditions, the extraction rate of rice bran oil reached 19.33%. [ Conclusion] This study laid solid foundation for further investigation and development of rice bran oil.

Analysis on Influential Factors for Anti-Infection Efficacy of Fluoroquinolones

Objective: To investigate factors contributed to anti-infection efficacy of fluoroquinolones (FQNS), and ultimately to provide guidelines for the application of such drugs. Methods: Clinical data of 519 infected patients who were treated with fluoroquinolones were analyzed retrospectively. According to the therapeutic efficacy of the drugs, cases were divided into 3 groups: clinical inefficient, improved and cured. 11 potential factors were investigated. The data were analyzed through logistic regression analysis to determine the main factors which influence therapeutic effects. Results: Ordinal logistic regression revealed that age (OR = 0.979, 95% CI: 0.969, 0.989), a variety of medicine (moxifloxacin-OR = 3.465, 95% CI: 1.396, 8.601;levofloxacin-OR = 4.605, 95% CI: 1.971, 10.760;ciprofloxacin-OR = 3.220, 95% CI: 1.089, 9.552;compared to lomefloxacin) (levofloxacin-OR = 2.591, 95% CI: 1.130, 5.944;compared to fleroxacin) and site of infection (respiratory system-OR = 3.016, 95% CI: 1.737, 5.236;urological system-OR = 4.077, 95% CI: 1.981, 8.391;digestive system-OR = 3.740, 95% CI: 1.849, 7.565) are main factors which influence the efficacy. Conclusion: Fluoroquinolones are more effective in the treatment of bacterial infection within drug’s indications in young population. Variety, dosage and intervals of the drugs should be adjusted according to disease condition.