重组动物疱疹病毒活载体疫苗的构建与应用研究进展     

杨明珠  陈晓春  宋佳诚  侯亚欣  李俊平 《中国畜牧兽医》2022,49(1):338-351

重组病毒活载体疫苗是通过基因工程方法构建的活载体疫苗，规避了传统疫苗的一些缺点，具有极大的优势和应用前景。目前被广泛用作重组病毒载体的动物疱疹病毒有火鸡疱疹病毒（Herpesvirus of turkey，HVT）、伪狂犬病病毒（Pseudorabies virus，PRV）、鸭瘟病毒（Duck enteritis virus，DEV）、鸡传染性喉气管炎病毒（Infectious laryngotracheitis virus，ILTV）等。对疱疹病毒基因组序列进行分析显示，其基因组大，复制非必需区域多，容纳外源基因的能力强。同时疱疹病毒具有宿主范围广泛、免疫持续期长、安全性较好及相关基因操作技术成熟等优点。笔者总结了当前构建重组动物疱疹病毒的主要方法，包括传统同源重组技术、细菌人工染色体（BAC）技术、Fosmid文库及CRISPR/Cas9基因编辑技术，简述了各个方法的基本原理及技术特点，比较了各个方法的优缺点，并分析了各个方法的最适运用条件，从而更准确地为研究工作提供理论及技术参考；对外源基因的表达方式进行分析，论证了不同启动子对外源基因表达的调控作用不同，同时对不同疱疹病毒的常用插入位点进行了研究成果的列举总结，并对当前重组病毒HVT、PRV、DEV及ILTV活载体疫苗的研究进展进行总结，对相关生物制品的注册应用信息进行了归纳，介绍了高选择率外源基因及高成功率插入位点，从而为相关生物制品的研制提供理论参考。  相似文献   

Potential of blended organic acids to improve performance and health of broilers infected with necrotic enteritis     

Alip Kumar  Mehdi Toghyani  Sarbast K. Kheravii  Lane Pineda  Yanming Han  Robert A. Swick  Shu-Biao Wu 《动物营养（英文）》2021,7(2):440

Organic acids (OA) and their blends have been shown to positively affect performance and health of broilers. However, the data in the literature are not consistent. This study examined the potential of blended short-chain fatty acids (SCFA) with medium-chain fatty acids (MCFA) as alternatives to antibiotic growth promoters (AGP) on performance, health and welfare of broilers infected with necrotic enteritis (NE). The additives used were: A) a blend of SCFA, MCFA, and a phenolic compound (SMP); B) a blend of free and buffered SCFA with MCFA (SMF); C) a blend of free and buffered SCFA with a high concentration of MCFA (SHM). A total of 1,404 Ross 308 one-day-old male parental chicks were randomly distributed into 78-floor pens with 13 replicates of 18 birds each. Six treatments were the following: T1, unchallenged control (UCC); T2, challenged control (CHC); T3, challenged group plus zinc bacitracin (BAC); T4, challenged group plus additive SMP; T5, challenged group plus additive SMF; T6, challenged group plus additive SHM. Challenged birds were gavaged with Eimeria spp. on d 9 and Clostridium perfringens EHE-NE18 on d 14. Post NE challenge and cumulatively, BWG, FCR, and nutrient digestibility of birds were compromised (P < 0.05) by NE challenge indicating a successful induction of sub-clinical NE. Additive SHM had higher BWG compared to CHC and BAC groups (P = 0.001; d 10 to 24) but not different from SMP and SMF groups (P > 0.05). All the 3 additive groups had lower FCR compared to CHC (P = 0.001; d 0 to 35), and exhibited similar jejunal lesions (d 16) compared to BAC and apparent ileal protein digestibility (d 21) compared to UCC and BAC groups (P > 0.05). Birds in additive SHM group had a higher concentration of serum IgA compared to all groups (P = 0.001) except additive SMF (P > 0.05; d 21). All the additive groups had lower footpad dermatitis and hock burns compared to CHC (P < 0.05). The findings suggest the potential of blended OA as alternatives to BAC to protect broilers from NE indicated by improved FCR, immunity, digestibility, and bird welfare.  相似文献