马铃薯原生质体转几丁质酶基因研究

以马铃薯四倍体普通栽培种Desiree脱毒试管苗叶片游离的原生质体为试材,采用PEG法转化菜豆几丁质酶基因。结果表明：DNA浓度为75 μg?mL-1时转化效率最高,采用延迟筛选的方法获得3株再生植株,PCR检测呈阳性。     

Seroprevalence for norovirus genogroups GII and GIV in captive non‐human primates

Noroviruses (NoVs) are a major cause of epidemic gastroenteritis in children and adults. Several pieces of evidence suggest that viruses genetically and antigenically closely related to human NoVs might infect animals, raising public health concerns about potential cross‐species transmission. The natural susceptibility of non‐human primates (NPHs) to human NoV infections has already been reported, but a limited amount of data is currently available. In order to start filling this gap, we screened a total of 86 serum samples of seven different species of NPHs housed at the Zoological Garden (Bioparco) of Rome (Italy), collected between 2001 and 2017, using an enzyme‐linked immunosorbent assay (ELISA) based on virus‐like particles (VLPs) of human GII.4 and GIV.1 NoVs. Antibodies specific for both genotypes were detected with an overall prevalence of 32.6%. In detail, IgG antibodies against GII.4 NoVs were found in 18 Japanese macaques (29.0%, 18/62), a mandrill (10.0%, 1/10), a white‐crowned mangabey (16.6%, 1/6) and in an orangutan (33.3%, 1/3). Twelve macaques (19.3%, 12/62), five mandrills (50.0%, 5/10), two chimpanzees (100%, 2/2) and a white‐crowned mangabey (16.6%, 1/6) showed antibodies for GIV.1 NoVs. The findings of this study confirm the natural susceptibility of captive NHPs to GII NoV infections. In addition, IgG antibodies against GIV.1 were detected, suggesting that NHPs are exposed to GIV NoVs or to antigenically related NoV strains.     

Effects of lysolecithin supplementation in low-energy diets on growth performance,nutrient digestibility,viscosity and intestinal morphology of broilers

1. The study aimed to investigate the effect of lysolecithin supplementation in low-energy diets on growth, nutrient digestibility and intestinal mucosa characteristics of broilers.

2. A total of 800 one-d-old Ross 308 broiler chickens were assigned to 4 dietary treatments consisting of 10 replicates of 20 broilers each. Broilers were fed with 4 different diets: (i) HE: positive control group broilers received a diet with unaltered energy; (ii) LE: negative control group broilers received a diet with lower energy of about 0.27 MJ/kg; (iii) LElys500: broilers received a diet similar to LE supplemented with 500 g/tn lysolecithin product (Lysoforte Booster Dry^TM); and (iv) LElys300: broilers received a diet similar to LE supplemented with 300 g/tn lysolecithin product. The experimental period was 42 d.

3. Body weight gain in treatments HE was higher than LE during the overall experimental period, while LElys500 and LElys300 had intermediate values. Feed conversion ratio was lower in HE and LElys500 than LE group, while the LElys300 had intermediate values. Fat digestibility was improved in both LElys 500 and LElys300 compared to the HE group. Apparent metabolisable energy (AMEn) was higher in HE, LElys500 and LElys300 than LE. Ileum viscosity at 42 d was also affected, being higher in LE group compared to HE. At 28 d mucosal thickness was lower both in LElys500 and LElys300 compared to HE and LE, while no difference occurred between treatment proliferation patterns of duodenal epithelial cells.

4. These findings indicated that lysolecithin supplementation at 500 g/tn of feed in low-energy diets maintained broiler performance. Supplementation of reformulated low-energy diets induced an increase in digesta viscosity. Lysolecithin supplementation resulted in variable alterations in the duodenum mucosal morphology.     

Avian influenza epidemiology in semi-intensive free ranging duck flocks of the Moyingyi Wetland in Bago East District,Myanmar

Highly pathogenic avian influenza virus subtype H5N1 first entered Myanmar in 2006 in the Mandalay District. Several H5N1 outbreaks followed and the one of Bago East District (2007) required post outbreak surveillance in the at-risk domestic duck population of the Moyingyi Wetland. A field epidemiological study based on a randomised prospective stratified study with five surveys provided the serological evidence that the avian influenza H5 subtype circulates in the domestic duck population and spreads to almost all the newly housed (and negative) flocks in the time span of a seasonal production cycle. Virological investigation was negative. The survival analysis showed that the probability of seroconversion increased rapidly over the study period, without significant difference among different agro-ecosystems. The analysis suggests that viral spread in the new cycle could be limited if control measures were adopted at the time new flocks are housed. The study recommends that future surveillance schemes for ducks are designed in a way to get as much information as possible from serological results which should drive virological sampling to determined farms.     

METHOD OF SEMEN COLLECTION AND ARTIFICIAL INSEMINATION IN SNAKES

This study focuses on the method for sperm extraction and artificial insemination in snakes. Ten adult healthy snakes (4.6) were included in the study (Pantherophis guttatus 1.3; Hydrodynastes gigas 1.1; Corallus hortulanus 1.1; and Sanzinia madagascariesis 1.1). Massage of the ventral aspect of the caudal third of the male snake body for 2 to 3 minutes was performed successfully for the semen collection. Both female and male P. guttatus and H. gigas were placed in brumation, with the female snakes being assessed for ovarian activity after emerging from dormancy. Only females showing ultrasonographic evidence of vitellogenic follicles were included in the study. S. madagascariensis and C. hortulanus were maintained at the same temperature through the year, and the ovarian activity was assessed ultrasonographically prior to artificially inseminating the animal. With the aid of a rigid endoscope, fresh semen was delivered through the cloaca and into the females’ oviducts using a catheter connected to the syringe. The technique failed in female S. madagascariensis and H. gigas. Two female P. guttatus laid eggs 2 months after artificial insemination, with hatchlings emerging following 2 months of development within the eggs. The third female corn snake did not lay an egg. The female C. hortulans produced eggs 4 months after insemination. The manual massage method of sperm collection in male snakes and endoscopy-assisted insemination in female snakes may be useful for conservation programs.     

BACTERIAL ULCERATIVE DERMATITIS IN A PIRANHA (PYGOCENTRUS NATTERERI) FED WITH FRESH FISH DIET

A red-bellied piranha (Pygocentrus nattereri), kept as a pet by a private owner, was presented for multifocal ulcerative lesions. Lesion biopsies were collected under general anesthesia and submitted for histopathologic and microbiologic examination. Histological examination revealed a bacterial necrotizing ulcerative dermatitis. From cultural analysis of the biopsy, Aeromonas hydrophila and Edwardsiella ictaluri were isolated. Multidrug resistance was observed in both isolates, except for neomycin and ceftazidime. Intramuscular injections of ceftazidime 22 mg/kg were administered until complete healing of the wound, except for small dermal scars that remained following treatment. Given that the piranha was maintained alone since it was purchased, except for occasional feedings with fresh nonfrozen goldfish, horizontal transmission of the infection from the prey species was considered the source of infection.     

幼龄仔猪PEDV感染肠道损伤模型的建立

试验旨在建立猪流行性腹泻病毒（PEDV）感染幼龄仔猪肠道损伤模型。试验选用16头7日龄健康幼龄仔猪（杜×长×大）,随机分为两个处理组：对照组和PEDV组,每个处理8个重复,每个重复1头猪。试验期为10 d,试验期间两个处理组饲喂相同的基础日粮。于试验第7天晚上对PEDV组仔猪口腔灌服PEDV病毒（剂量为10^4.5 TCID₅₀）,对照组灌服等量的生理盐水。于试验第10天早上空腹灌服D-木糖（0.1 g/kg体重）,1 h后前腔静脉采血,屠宰取样,取十二指肠、空肠、回肠等组织样品,测定平均日增重（ADG）、腹泻率（DR）、肠道形态结构、肠道黏膜损伤相关基因mRNA水平。试验结果表明：①PEDV感染显著降低了仔猪ADG（P<0.05）,极显著提高了仔猪腹泻率（P<0.01）;②PEDV感染极显著降低了血浆D-木糖含量、空肠和回肠绒毛高度、十二指肠、空肠和回肠绒毛高度与隐窝深度的比值（P<0.01）,显著提高了十二指肠和空肠隐窝深度（P<0.05）;③PEDV感染极显著提高了仔猪空肠黏膜PEDV M基因的相对表达量（P<0.01）,极显著降低了肠绒毛蛋白（villin）和肠型脂肪酸结合蛋白（i-FABP）基因的相对表达量（P<0.01）。以上结果表明,口腔灌服PEDV可以成功诱导建立幼龄仔猪肠道损伤模型。     

郁金香离体快繁技术研究

以2个郁金香品种"阿波罗"和"琳.马克"为试材,用不同时期、不同部位、不同类型的郁金香鳞片作为外植体,以MS为基本培养基,分别添加不同质量浓度的6-BA、NAA、IAA和活性炭,研究不同外植体以及不同培养基对小鳞茎诱导的影响。结果表明:经春化处理后的鳞片作为外植体诱导小鳞茎的效果最好,鳞片部位以中层最适宜诱导小鳞茎;以带鳞茎盘的双鳞片作诱导小鳞茎的外植体效果最好;最适宜"阿波罗"小鳞茎诱导的激素组合为MS+6-BA 2mg/L+NAA 2mg/L+IAA 0.3mg/L;最适宜"琳.马克"小鳞茎诱导的激素组合为MS+6-BA 2mg/L+NAA 2mg/L+IAA 0.1mg/L;活性炭对小鳞茎的诱导有促进作用;最适宜的暗处理时间为7d。     

CryⅢA 基因植物表达载体构建及马铃薯遗传转化简

 利用Ｉｎ-Ｆｕｓｉｏｎ技术将酶切位点不匹配、目的基因内部含载体酶切位点的CRY  ⅢA 基因和植物表达载体ｐＢＩ１２１相连接，分别成功构建了组成型启动子ＣａＭＶ３５Ｓ和马铃薯茎叶特异表达启动子ＳＴ-ＬＳ１驱动的CRY  ⅢA 基因植物表达载体。利用冻融法将２个重组质粒转入根癌农杆菌ＬＢＡ４４０４，转化马铃薯栽培品种陇薯３号和甘农薯２号获得了转化植株，经卡那霉素筛选和ＰＣＲ 测，共有１０株阳性植株CRY  ⅢA 基因成功整合到马铃薯基因组中。经实时荧光定量ＰＣＲ 检测表明，CRY  ⅢA 基因在ＣａＭＶ３５Ｓ驱动的CRY  ⅢA 转基因植株的根、茎、叶中均有表达，且在叶中表达量较高，茎和根次之；在马铃薯茎叶特异表达启动子ＳＴ-ＬＳ１驱动的CRY  ⅢA 转基因植株中，在根中未见表达，仅在茎、叶中表达，且在叶中表达量较高。