奶牛非饲草来源纤维营养研究进展

本文在总结分析国内外最新研究成果的基础上,对非饲草来源纤维(NFFS)对奶牛的营养作用和生理影响及其机理进行了综述,主要从NFFS部分替代饲草对奶牛生产性能、瘤胃草垫层和瘤胃发酵的影响,以及NFFS部分替代精料对饲料效率、生产性能和亚急性瘤胃酸中毒(SARA)奶牛生理的影响等方面进行论述,旨在为NFFS饲料在奶牛饲粮中的科学合理利用提供理论参考和依据。     

Cashew nut shell liquid potentially mitigates methane emission from the feces of Thai native ruminant livestock by modifying fecal microbiota

The methane-mitigating potency of cashew nutshell liquid (CNSL) was evaluated by investigating gas production from batch cultures using feces from Thai native ruminants that had been incubated for different periods. Feces was obtained from four Thai native cattle and four swamp buffaloes reared under practical feeding conditions at the Kasetsart University farm, Thailand. Fecal slurry from the same farm was also included in the analysis. CNSL addition successfully suppressed the methane production potential of feces from both ruminants by shifting short chain fatty acid profiles towards propionate production. Methane mitigation continued for almost 150 days, although the degree of mitigation was more apparent from Day 0 to Day 30. Bacterial and archaeal community shifts with CNSL addition were observed in feces from both ruminants; specifically, Bacteroides increased, whereas Lachnospiraceae and Ruminococcaceae decreased in feces to which CNSL was added. Fecal slurry did not show marked changes in gas production with CNSL addition. The findings showed that the addition of CNSL to the feces of ruminants native to the Southeast Asian region can suppress methane emission. Because CNSL can be easily obtained as a byproduct of the local cashew industry in this region, its on-site application might be ideal.     

湖羊羔羊早期断奶前后瘤胃发酵与微生物区系的变化

本试验旨在研究湖羊羔羊早期断奶前后的瘤胃发酵与微生物区系变化,为幼龄反刍动物瘤胃发育变化理论以及羔羊的早期培育等提供依据。选择初生重接近的湖羊公羔(3.81 kg±0.55 kg)16只,1~7日龄饲喂母乳,8日龄与母羊分离,开始饲喂代乳粉(按8日龄体重的2%,分3次等量饲喂)和开食料(自由采食),35日龄断奶。分别于断奶前(21日龄)、后(42日龄)各选择5只羔羊进行屠宰,采集瘤胃内容物,测定瘤胃发酵、酶活和微生物区系。结果表明,断奶后羔羊的瘤胃总挥发性脂肪酸、乙酸、丙酸、丁酸及纤维素酶和α-淀粉酶活性均极显著高于断奶前(P<0.01)。断奶后瘤胃菌群多样性和丰富度均低于断奶前(P<0.05)。断奶前后的优势菌门均为拟杆菌门(Bacteroidetes)和厚壁菌门(Firmicutes),其中,拟杆菌门为第一优势菌门,在断奶前后分别占61.96%和65.36%,厚壁菌门为第二优势菌门,在断奶前后分别占32.08%和24.03%;两菌门之和在断奶前后分别占瘤胃总菌门的94.04%和89.39%。断奶前后的优势菌属均为unidentified_Prevotellaceae,分别占21.85%和38.49%。断奶前后羔羊瘤胃微生物的功能没有显著变化,都主要集中在复制和修复、碳水化合物代谢和翻译等途径。以上结果说明,羔羊早期断奶后的瘤胃发酵和酶活增强,菌群多样性和丰富度有所降低,在早期断奶前后的优势菌群和功能相似。     

奶牛场温室气体排放与减排措施

奶牛养殖在产能提升的同时也排放了大量温室气体。本文梳理了奶牛养殖场温室气体排放的重点环节,主要分为奶牛养殖活动温室气体排放以及牛场日常运行耗能两个方面;结合奶牛养殖肠道发酵和粪污管理的温室气体核算方法,归类整理了主要的减排措施,包括进行提高饲料质量和转化效率、粪污高效管理、清洁能源替代等方式,助力奶牛养殖实现低碳乃至零碳排放。     

A review of okara (soybean curd residue) utilization as animal feed: Nutritive value and animal performance aspects

Year by year, huge quantities of by-products are generated during the manufacturing process of soybean-based products. Okara is one of the by-products, and it is an insoluble portion of the soybean. It consists of high moisture (8.4–22.9%); on dry matter basis, it contains high metabolizable energy (9.0–14.2 MJ/kg) and other components that include crude protein (20.9–39.1%), crude fiber (12.2–61.3%), crude fat (4.9–21.5%), and ash (3.4–5.3%). Fermentation of okara improves its nutritional quality and reduces its anti-nutrient contents. Due to animals' palatability, okara can be used to replace the soybean meal/concentrate feed partially or completely in ruminant's diet and partially in nonruminant's diet. Okara feeding does not depress the intake, digestibility, growth, milk production, blood metabolic profiles, and meat quality of animals. However, this by-product decays quickly due to its high moisture content, and its heavy weight and sticky nature make it difficult to process and expensive to dry using conventional methods. This paper thoroughly summarizes the utilization of okara as animal feed in the cause of developing a general guideline with favorable levels of inclusion in the diets of animals for its exploitation and valorization. This review will encourage further research to develop eco-friendly and value added feed for animals.     

芹菜发酵液对小鼠溃疡性结肠炎的保护作用研究

本试验旨在研究发酵前后芹菜汁的主要功能成分变化和芹菜发酵液对葡聚糖硫酸钠（DSS）诱导的小鼠溃疡性结肠炎（UC）的防治及免疫调节作用。选取50只4周龄雄性C57BL/6小鼠随机分为空白组、模型组及低、中、高浓度芹菜发酵液组,每组10只。按10 μL/g BW的剂量标准给空白组和模型组小鼠灌胃无菌生理盐水,其他组小鼠则灌胃不同浓度的芹菜发酵液,持续7 d。从第8天开始,除空白组自由饮用无菌水外,其余组连续7 d自由饮用3% DSS溶液;在此过程,每日称量体重,进行疾病活动指数（DAI）评分。在第14天,通过摘眼球取血法获得全血,随后脱颈处死小鼠,解剖取出结肠组织测量长度并通过苏木素-伊红（HE）染色法制作病理切片,进行病理学分析。以流式细胞仪分选技术检测外周血中CD4⁺/CD8⁺T淋巴细胞比值,以酶联免疫吸附法（ELISA）检测血清中肿瘤坏死因子-α（TNF-α）、白细胞介素-6（IL-6）、γ-干扰素（IFN-γ）和IL-10的含量。结果表明：①芹菜汁经发酵后,总酸、总糖、总多酚、类黄酮、维生素C和超氧化物歧化酶（SOD）等多种活性成分的含量均显著增加（P<0.05）。②与模型组相比,芹菜发酵液高浓度组能减少DSS引起的小鼠体重损失（P<0.01）、结肠缩短（P<0.01）和DAI降低（P<0.05）。③组织病理学分析结果表明,各发酵液组的UC症状均得到不同程度改善,肠腺结构相对完整,杯状细胞轻微减少,仅有少量淋巴细胞和中性粒细胞浸入。④流式细胞仪分析结果显示,相较于模型组,发酵液组全血CD4⁺/CD8⁺T淋巴细胞比值极显著升高（P<0.01）。⑤ELISA检测结果显示,与模型组相比,芹菜发酵液组的IL-6、TNF-α和IFN-γ含量极显著下调（P<0.01）,IL-10的含量极显著上调（P<0.01）。综上,芹菜汁经发酵后主要功能活性成分均得到显著提高,并且发酵芹菜液对DSS诱导的小鼠UC具有一定的防治和免疫调节作用,其作用机制可能与维持外周血中CD4⁺与CD8⁺T淋巴细胞平衡,以及抑制促炎症因子（TNF-α、IL-6和IFN-γ）表达,促进抗炎症因子（IL-10）表达有关。     

家庭猪场防控非洲猪瘟的关键点分析

非洲猪瘟对家庭猪场的生产稳定性带来极大的挑战。文章分析了家庭猪场防控非洲猪瘟存在的问题及对关键点针对性的防控措施。     

非离子表面活性剂对反刍动物瘤胃发酵及生产性能的影响研究进展

综述了非离子表面活性剂对反刍动物瘤胃微生物数量、酶活性、瘤胃发酵特性、饲料消化率和生产性能等方面的影响作用以及与其他饲料添加剂的互作效应,并就其作用机制进行了阐述。     

Construction and Identification of Yeast Surface Display Libraries of Ovis aries DRA Gene Exon 2

The specific primers were designed according to Ovis aries DRA gene sequence deposited in GenBank and the multiple cloning site of the plasmid pYD1,which was a vector used for protein surface display on Saccharomyces cerevisiae.The gene encoding DRA was amplified by PCR using the genomic RNA of Ovis aries.The 762 bp fragment was cloned and released in GenBank and registration number was KR422362.The PCR product was inserted into the yeast surface display plasmid vector pYD1 by double enzyme digestion.It was indicated that DRA gene was successfully integrated into the genome.Dot mutation was made at both ends of exon 2 in DRA gene for making restriction enzyme cutting site and design the exon 2 specific primers according to mutated Ovis aries DRA gene sequence.Sequenced exon 2 amplification products based on DNA pooling of sheep large sample template was analyzed the polymorphic loci.The polymorphic exon 2 246 bp fragment was obtained by double enzyme digestion and connected to surface display restructuring mutation carriers pYD1-DRA by the same double enzyme digestion,and then we successfully constructed yeast surface display libraries.We transformed it into Saccharomyces cerevisiae EBY100 cell.Yeast monoclone was identified by PCR amplification and sequencing,and we confirmed that DRA gene had been integrated into Saccharomyces cerevisiae genome.After galactose induced,it was detected that DRA gene library had been successfully demonstrated on the yeast cell surface under the fluorescence microscope by immunofluorescence method.     

ASVCP guidelines: quality assurance for portable blood glucose meter (glucometer) use in veterinary medicine

Portable blood glucose meters (PBGM, glucometers) are a convenient, cost effective, and quick means to assess patient blood glucose concentration. The number of commercially available PBGM is constantly increasing, making it challenging to determine whether certain glucometers may have benefits over others for veterinary testing. The challenge in selection of an appropriate glucometer from a quality perspective is compounded by the variety of analytic methods used to quantify glucose concentrations and disparate statistical analysis in many published studies. These guidelines were developed as part of the ASVCP QALS committee response to establish recommendations to improve the quality of testing using point‐of‐care testing (POCT) handheld and benchtop devices in veterinary medicine. They are intended for clinical pathologists and laboratory professionals to provide them with background knowledge and specific recommendations for quality assurance (QA) and quality control (QC), and to serve as a resource to assist the provision of advice to veterinarians and technicians to improve the quality of results obtained when using PBGM. These guidelines are not intended to be all‐inclusive; rather they provide a minimum standard for management of PBGM in the veterinary setting.