四种兔艾美耳球虫卵囊产量的比较

分别用4种兔艾美耳球虫经口接种45日龄无球虫感染兔,接种剂量为1×104个卵囊/兔。感染后4d～20d,以麦克马斯特氏法计数每天排出的卵囊。结果表明,肠艾美耳球虫排卵量最多,为365.76×106个,中型艾美耳球虫为317.26×106个、黄艾美耳球虫为304.36×106个,大型艾美耳球虫排卵量最少,为200.12×106个。大型艾美耳球虫在感染后第6.5天有卵囊排出,第10.5天达到高峰(66.50×106个/只),占总量的33.23%;肠艾美耳球虫在感染后第9天有卵囊排出,第13天达到高峰(138.40×106个/只),占总量的37.83%;黄艾美耳球虫在感染后第9天有卵囊排出,第11天达到高峰(102.80×106个/只),占总量的33.78%;中型艾美耳球虫在感染后第4.5天有卵囊排出,第6.5天达到高峰(167.8×106个/只),占总量的52.89%。     

用裂殖体和卵囊抗原检测鸡球虫血清抗体

将柔嫩艾美球虫孢子化卵囊和第二代裂殖体制成可溶性抗原，用酶联免疫吸附试验（ＥＬＩＳＡ）检测实验感染性柔嫩艾美球虫肉用鸡和ＳＰＦ单冠白来航蛋鸡的血清抗体。肉鸡于１５日龄接种卵囊，接种后１９天，ＥＬＩＳＡ值迅速增加，接种后２９和３２天，抗裂殖体和卵囊原ＥＬＩＳＡ值均达最高值。抗裂殖体抗原ＥＬＩＳＡ值明显高于抗卵囊抗原ＥＬＩＳＡ值。ＳＰＦ蛋鸡于１５日龄接种孢子化卵囊，接种后７天，ＩＬＩＳＡ值迅速增加，抗     

毒害艾美耳球虫未孢子化卵囊壁的分离与纯化

用毒害艾美耳球虫孢子化卵囊接种50只15日龄无球虫感染的雏鸡,感染后第6~12天,每隔12 h收集1次粪便,按常规方法分离卵囊。未孢子化卵囊经次氯酸钠溶液处理后,用1.1 mol/L蔗糖溶液漂浮法纯化卵囊。采用玻璃珠涡旋法破碎卵囊壁,最后用孔径10.0μm的聚对苯二甲酸乙二醇酯(PET)膜过滤获得纯化的卵囊壁。研究结果为进一步研究毒害艾美耳球虫卵囊壁的结构及其蛋白组成奠定了基础。     

毒害艾美耳球虫鸡胚培养研究

为了建立毒害艾美耳球虫(Eimeria necatrix)的鸡胚培养体系,用毒害艾美耳球虫子孢子分别接种8～11日龄鸡胚以确定最佳接种日龄,用不同剂量子孢子接种同一日龄鸡胚以确定最佳子孢子接种剂量,并在子孢子混悬液中分别加入不同剂量的胰岛素和叶酸以观察对球虫在鸡胚中发育的影响.结果显示,毒害艾美耳球虫子孢子接种9日龄的鸡胚,其卵囊产量(平均每只胚的卵囊量)和卵囊成熟率均为最高,成熟率达到99%;当每个鸡胚接种子孢子1×104个时,其卵囊产量最高;在子孢子混悬液中分别加入胰岛素1 000 U/mL、叶酸0.05 mg/mL,均能明显增加鸡胚中的卵囊产量.本文通过对毒害艾美耳球虫的鸡胚接种日龄、子孢子接种剂量、营养物质添加等因素的研究,初步建立了毒害艾美耳球虫的鸡胚培养体系.     

毒害艾美耳球虫晚熟系选育及其生活史研究

以剂量为l200～20000个孢子化卵囊／羽的毒害艾美耳球虫(E．necatrix)北京株(中熟系)感染3日龄京星黄羽肉仔鸡，收集感染后第11天粪便中卵囊，孢子化后接种无球虫鸡进行连续传代，经传代16次后，发现其排卵囊高峰较母株(中熟系)推迟了2天，即由接种后第7天推迟到第9天，且连续3代排卵囊高峰均出现在第9天，有较好的稳定性。生活史研究表明，其各阶段虫体均比母株的大，但潜在期不变，推测可能是选育得到的晚熟系卵囊中尚含有少量中熟系卵囊的缘故。     

柔嫩艾美耳球虫对禽流感疫苗的免疫增强作用研究

为了研究柔嫩艾美耳球虫对雏鸡免疫禽流感疫苗的免疫增强作用,试验将7日龄AA肉鸡随机分为4组,每组20只,1组试验鸡皮下注射柔嫩艾美耳球虫孢子化卵囊,同时免疫禽流感H5亚型灭活疫苗;2组试验鸡皮下注射柔嫩艾美耳球虫孢子化卵囊,同时免疫磷酸盐缓冲液;3组试验鸡皮下注射磷酸盐缓冲液,同时免疫禽流感H5亚型灭活疫苗;4组试验鸡皮下注射磷酸盐缓冲液,同时免疫磷酸盐缓冲液。在免疫后第7,14,21,28天,各组随机取5只鸡采血、称重,采集胸腺、脾脏、法氏囊,计算免疫器官指数,采用血凝抑制试验检测血清中禽流感抗体效价。结果表明:各组试验鸡的平均体重差异不明显,柔嫩艾美耳球虫孢子化卵囊与禽流感灭活疫苗共免疫不会影响试验鸡的日增重;柔嫩艾美耳球虫与禽流感疫苗联合免疫可以促进雏鸡免疫器官的生长发育,提高雏鸡免疫器官指数和禽流感抗体效价。说明柔嫩艾美耳球虫可以调节机体对疫苗的免疫反应,促进雏鸡的体液免疫应答。     

不同发育期两种艾美耳球虫在鸡消化道内的分布

对柔嫩艾美耳球虫Eimeria teenlla和巨型艾美耳球虫Eimeria maxima的卵囊、孢子囊和子孢子在鸡消化道和粪便中的分布情况进行了研究。口服接种柔嫩艾美耳球虫卵囊第1小时后,盲肠内孢子囊数为3.4×10~8、以后则逐渐减少;而子孢子数增加且直到接种后第12小时仍保持一个高水平。其它肠段只有少量的孢子囊和子孢子。在接种巨型艾美耳球虫卵囊后的第2小时,主要在空肠内发现有大量的子孢子。研究发现,柔嫩艾美耳球虫和巨型艾美耳球虫的绝大多数子孢子分别寄居在盲肠和空肠内,表明每种球虫子孢子侵袭部位的特异性在侵袭发生前就确定了。     

球虫感染与铁吸收

球虫感染可影响家禽消化道对多种营养物质的吸收。4周龄仔鸡感染堆型艾美尔球虫、毒害艾美耳球虫、布氏艾美尔球虫及柔嫩艾美尔球虫形成孢子卵囊的试验,于感染卵囊后第6天增重率降低,大部分仔鸡转入严重感染阶段,于感染后35天体重恢复到对照鸡的水平。     

柔嫩艾美耳球虫的抗原分析

本文采用十二烷基硫酸钠－聚丙烯酰胺凝胶电泳，免疫印渍技术，用抗柔嫩艾美耳球虫抗体分析了第二代型殖子、子孢子和未孢子化卵囊的蛋白质。ＳＤＳ－ＰＡＧＥ电泳银染表明第二代裂殖子主要蛋白质为：１７．６ＫＤ，２９．９ＫＤ，３８．９ＫＤ和５３．７ＫＤ，但用抗Ｅ．ｔｅｎｅｌｌａ抗体免疫印渍法检测出的主要抗原为：７８．０ＫＤ，８３．２ＫＤ和９５．５ＫＤ，这说明并不是含量高的蛋白质就是产生抗体的抗原；子孢子蛋白质含     

兔斯氏艾美耳球虫感染模型的建立及病理学初步研究

建立兔斯氏艾美耳球虫感染模型,为研究斯氏艾美耳球虫感染兔的有效防治方法提供适合的动物模型。2月龄普通级新西兰兔16只,分组单笼饲养。从自然感染的肝脏中收集斯氏艾美耳球虫卵囊,培养孢子化,孢子化的卵囊1.0×105个/mL,3mL孢子化卵囊口服感染新西兰兔,建立兔斯氏艾美耳球虫感染模型,并对感染1个月后的新西兰兔的肝脏、十二指肠进行病理学观察比较。结果显示:斯氏艾美耳球虫对新西兰兔部分致病性观察发现,新西兰兔在感染后出现明显的临床症状,严重制约了其生长发育。形态学观察发现肝脏感染严重,表面布满白色结节,胆囊中胆汁浓稠,颜色呈金黄色,而十二指肠虽未感染球虫,却也有较显著的病变。病理学观察发现肝脏中存在大量斯氏艾美耳球虫,十二指肠中不存在球虫,但组织结构亦被破坏,十二指肠绒毛遭到严重破坏。结果表明:本试验成功建立了兔斯氏艾美耳球虫感染模型。     

Differential protein profiles in duck meat during the early postmortem storage period

The present study was designed to investigate proteomic differences in duck breast muscle during the early postmortem storage period. The meat quality was evaluated at 0 hr and 24 hr postmortem at 4°C in Pekin ducks, black Muscovy ducks and Mule ducks. Differentially expressed proteins were detected by two‐dimensional gel electrophoresis (2‐DE) and matrix‐assisted laser desorption ionization‐time‐of‐flight mass spectrometry (MALDI‐TOF/TOF MS) at 0 hr and 24 hr postmortem in the three duck breeds. The results showed that 53 proteins spots were differentially expressed at 0 hr and 24 hr postmortem at 4°C in Pekin ducks, 75 spots in black Muscovy ducks, and 72 spots in Mule ducks. A total of 30 (10 spots for each breed) were selected for identification by mass spectrometry. Seven proteins were identified in Pekin ducks, eight in black Muscovy ducks and seven in Mule ducks. Moreover, the above results obtained by 2‐DE and MALDI‐TOF/TOF MS were confirmed by western blotting. To our knowledge, this study is the first to provide insights into the protein profiles of ducks during postmortem storage and provides a better understanding of the biochemical processes that contribute to duck meat quality.     

Serological survey and risk factors for Toxoplasma gondii in domestic ducks and geese in Lower Saxony, Germany

To obtain estimates for the prevalence of Toxoplasma gondii infection in ducks and geese in Germany, enzyme-linked immunosorbent assays (ELISA) were established based on affinity-purified T. gondii tachyzoite surface antigen 1 (TgSAG1) and used to examine duck and goose sera for T. gondii-specific antibodies. The results of 186 sera from 60 non-infected ducks (Anas platyrhynchos) and 101 sera from 36 non-infected geese (Anser anser) as well as 72 sera from 11 ducks and 89 sera from 12 geese inoculated experimentally with T. gondii tachyzoites (intravenously) or oocysts (orally) and positive in a T. gondii immunofluorescent antibody test (IFAT) were used to select a cut-off value for the TgSAG1-ELISA. Sera obtained by serial bleeding of experimentally inoculated ducks and geese were tested to analyze the time course of anti-TgSAG1 antibodies after inoculation and to assess the sensitivity of the assays in comparison with IFAT. In ducks, IFAT titres and ELISA indices peaked 2 and 5 weeks p.i with tachyzoites, respectively. Only three of six geese inoculated with tachyzoites at the same time as the ducks elicited a low and non-permanent antibody response as detected by the IFAT. In the TgSAG1-ELISA, only a slight increase of the ELISA indices was observed in four of six tachyzoite-inoculated geese. By contrast, inoculation of ducks and geese with oocysts led to an increase in anti-TgSAG1 antibodies within 1 or 2 weeks, which were still detectable at the end of the observation period, i.e. 11 weeks p.i. Inoculation of three ducks and three geese with oocysts of Hammondia hammondi, a protozoon closely related to T. gondii, resulted in a transient seroconversion in ducks and geese as measured by IFAT or TgSAG1-ELISA. Using the newly established TgSAG1-ELISA, sera from naturally exposed ducks and geese sampled in the course of a monitoring program for avian influenza were examined for antibodies to T. gondii; 145/2534 (5.7%) of the ducks and 94/373 (25.2%) of the geese had antibodies against TgSAG1. Seropositive animals were detected on 20 of 61 duck and in 11 of 13 goose farms; the seroprevalences within positive submissions of single farms ranged from 2.2% to 78.6%. Farms keeping ducks or geese exclusively indoors had a significantly lower risk (odds ratio 0.05, 95% confidence interval 0.01-0.3) of harboring serologically positive animals as compared with farms where the animals had access to an enclosure outside the barn.     

Effect of species,breed and route of virus inoculation on the pathogenicity of H5N1 highly pathogenic influenza (HPAI) viruses in domestic ducks

H5N1 highly pathogenic avian influenza (HPAI) viruses continue to be a threat to poultry in many regions of the world. Domestic ducks have been recognized as one of the primary factors in the spread of H5N1 HPAI. In this study we examined the pathogenicity of H5N1 HPAI viruses in different species and breeds of domestic ducks and the effect of route of virus inoculation on the outcome of infection. We determined that the pathogenicity of H5N1 HPAI viruses varies between the two common farmed duck species, with Muscovy ducks (Cairina moschata) presenting more severe disease than various breeds of Anas platyrhynchos var. domestica ducks including Pekin, Mallard-type, Black Runners, Rouen, and Khaki Campbell ducks. We also found that Pekin and Muscovy ducks inoculated with two H5N1 HPAI viruses of different virulence, given by any one of three routes (intranasal, intracloacal, or intraocular), became infected with the viruses. Regardless of the route of inoculation, the outcome of infection was similar for each species but depended on the virulence of the virus used. Muscovy ducks showed more severe clinical signs and higher mortality than the Pekin ducks. In conclusion, domestic ducks are susceptible to H5N1 HPAI virus infection by different routes of exposure, but the presentation of the disease varied by virus strain and duck species. This information helps support the planning and implementation of H5N1 HPAI surveillance and control measures in countries with large domestic duck populations.     

新型鹅细小病毒研究进展

鸭细小病毒病是由鹅细小病毒(Goose parvovirus,GPV)或番鸭细小病毒(Muscovy duck parvovirus,MDPV)引起的一种传染病。经典MDPV和GPV毒株引起的病鸭主要症状为腹泻、脚软、渗出性肠炎,三周龄内雏鸭感染发病率和死亡率都很高。但是2008年下半年以来,福建省、浙江省、安徽省及江苏省等地的雏半番鸭和樱桃谷鸭陆续出现一种新型细小病毒病,该病发病率10%~30%,病死率低于3%,临床症状主要为软脚、短嘴和生长障碍。通过对该病病原进行全基因组测序及系统发育树分析,结果发现该病原与鹅细小病毒亲缘性很近。本文通过比较新型鹅细小病毒(Novel goose parvovirus,N-GPV)与经典的MDPV和GPV在基因组、感染宿主范围和致病性的区别,为新型鹅细小病毒病的防控提供理论依据。     

番鸭细小病毒病病原的血清学检测与PCR鉴定

为了解安徽省番鸭细小病毒病的流行情况,采用酶联免疫吸附试验(ELISA)对该省内部分番鸭群进行鹅细小病毒的血清抗体检测,同时对疑似病鸭进行了病原的PCR检测。结果发现,在被检测的44份血清样本中鹅细小病毒血清抗体阳性率高达34.1%;PCR检测结果显示,所检测的样品中,有2份为鹅细小病毒阳性,1份为番鸭细小病毒阳性,且3份被检样品均来自雏番鸭。该研究结果表明,该省番鸭群中存在鹅细小病毒和番鸭细小病毒感染,应采取有效的预防控制措施。     

不同羽色和性别番鸭屠宰性能及肌肉成分比较研究

研究旨在比较不同羽色及性别番鸭在屠宰性能及肌肉成分上的差别,为选育优良番鸭品种提供依据。试验选取1日龄黑羽番鸭、白羽番鸭及黑白花番鸭公、母共324羽,按羽色、性别分为6个处理,每处理设6个重复,每重复9只鸭,各处理饲喂相同日粮,试验期90d。结果表明：雄性黑羽番鸭屠宰率、全净膛率显著高于雄性白羽及黑白花羽番鸭（P〈0．05）,而雌性黑白花番鸭及白羽番鸭的胸肌率和瘦肉率相近且均显著高于雌性黑羽番鸭（P〈0．05）;各处理番鸭肌肉中汞、镉、砷、铅含量无显著差异（P〉0．05）,且均很微量;各同羽色雄性番鸭肌肉水分、无氮浸出物和粗蛋白质含量均基本略高于其同羽色雌性番鸭,而各处理雌性番鸭肌肉粗脂肪、粗灰分含量则高于其同羽色的雄性番鸭;雄性白羽番鸭和黑白花番鸭肌肉粗蛋白质含量相近且均显著高于雄性黑羽番鸭（P〈0．05）;各同羽色番鸭中基本上肌肉氨基酸含量均以雄性高于雌性,而同性别的番鸭比较,雄性白羽番鸭肌肉中多种氨基酸的含量显著高于雄性黑羽及雄性黑白花羽番鸭（P〉0．05）;同时雌性各羽色番鸭肌肉中多种氨基酸含量呈现出：黑白花番鸭〉黑羽番鸭〉白羽番鸭,但该趋势不显著（P〉0．05）。试验结果表明,雄性黑羽番鸭屠宰性能有一定优势,白羽番鸭肌肉养分和氨基酸含量优势明显。     

Testosterone concentrations,testes weight and morphology of mule drakes (Muscovy drake X Khaki Campbell)

1. Mule ducks were produced by naturally mating Muscovy drakes and Khaki Campbell ducks. 2. Semen was collected from 6-month-old mule drakes via an artificial vagina. The fluid was clear without any spermatozoa or spermatids. 3. Testes from 27-week-old mule drakes were smaller in size than those of Khaki Campbell drakes but heavier than Muscovy males of the same age. Histological sections of these testes revealed that spermatogenesis was not complete. 4. Testosterone concentration in the mule drakes was higher than in Muscovy males but similar to Khaki Campbell drakes. 5. Mule drakes have strong sexual drives as a result of high concentrations of testosterone, but, because spermatogenesis is incomplete, their semen had no sperm.     

4个微卫星标记分析6个鸭群体之间的遗传关系

利用4对微卫星引物（AJ272577、AJ272578、AJ272579和AJ272580）对6个鸭群体（绍鸭、番鸭、樱桃谷鸭、北京鸭（Z4、Z1）和奥白星鸭）300只鸭的等位基因频率、群体多态信息含量、有效等位基因数、杂合度和遗传距离进行了检测。结果表明：4个微卫星基因座在6个鸭群体中均存在多态性，可以用于鸭的遗传多样性评估；且基因座AJ272578变异最大，基因座AJ272579变异最小，从不同群体来看，北京鸭Z1的遗传变异最大，奥白星鸭的遗传变异最小。基于Nei氏标准遗传距离，采用UPGMA方法构建了系统发生树，将绍鸭和樱桃谷鸭归为一类，北京鸭Z1、奥白星鸭和北京鸭Z4归为一类，番鸭归为一类。鸭的微卫星基因分型技术为检测品种（群体）之间的遗传关系提供了一个有用的工具。     

Humoral immune response of the duck to duck hepatitis virus: virus-neutralizing vs. virus-precipitating antibodies

Ducks were induced to develop high-level duck hepatitis virus (DHV)-neutralizing antibodies by inculation with a chicken-embryo-adapted DHV via subcutaneous, intramuscular, and intratracheal routes. Administration of the DHV orally in a gelatin capsule failed to stimulate immune response in the ducks. Contact controls of these ducks also remained negative for anti-DHV antibodies. These observations indicated that the DHV administered orally, in gelatin capsule, failed to infect the ducks. None of numerous duck anti-DHV immune sera, with virus-neutralizing activity in the range of 1.8 to 5.57 log10 median- embryo-infective-dose (EID50) neutralization index, developed precipitin lines against a variety of DHV preparations tested in low- and high-ionic-strength agar. The results suggest that the agar-gel immunodiffusion test is unsuitable for serologic testing of duck sera for anti-DHV antibody activity. Virus-neutralizing activity was revealed in both immunoglobulin M (IgM) and IgG classes of sera of actively immunized ducks. Immunodiffusion tests of Sephadex G-200 fractions of 1-day-old duckling sera with monospecific rabbit anti-duck IgM (DIgM) serum failed to detect DIgM. These results demonstrated that the IgM is not being transferred from the dam to the newly hatched ducklings. Seven- and 14-day-old ducks had DIgM in their sera. However, this IgM had no DHV-neutralizing activity, indicating that it was newly developed by the ducklings, which had no active DHV immune response, not having been exposed to DHV.     

Comparative pathological studies on domestic geese (Anser anser domestica) and Muscovy ducks (Cairina moschata) experimentally infected with parvovirus strains of goose and Muscovy duck origin

Parvovirus infection of Muscovy ducks caused by a genetically and antigenically distinct virus has been reported from Germany, France, Israel, Hungary, some Asian countries and the USA. The pathological changes include those of degenerative skeletal muscle myopathy and myocarditis, hepatitis, sciatic neuritis and polioencephalomyelitis. In the study presented here, day-old and 3-week-old goslings and Muscovy ducks were infected experimentally with three different parvovirus strains (isolates of D-216/4 from the classical form of Derzsy's disease, D-190/3 from the enteric form of Derzsy's disease, and strain FM from the parvovirus disease of Muscovy ducks). All three parvovirus strains caused severe disease in both day-old and 3-week-old Muscovy ducks but in the goslings only the two strains of goose origin (D-216/4 and D-190/3) caused disease with high (90-100%) mortality when infection was performed at day old. Strain FM (of Muscovy duck origin) did not cause any clinical signs or pathological lesions in the goslings. In the day-old goslings and Muscovy ducks the principal pathological lesions were severe enteritis with necrosis of the epithelial cells (enterocytes) of the mucous membrane and the crypts of Lieberkühn, and the formation of intranuclear inclusion bodies. Other prominent lesions included hepatitis and atrophy (lymphocyte depletion) of the lymphoid organs (bursa of Fabricius, thymus, spleen). In goslings infected with the strain originating from the classical form of Derzsy's disease mild myocarditis was also detected. After infection at three weeks of age, growth retardation, feathering disorders, myocardial lesions (degeneration of cardiac muscle cells, lympho-histiocytic infiltration) and hepatitis were the most prominent lesions in both geese and Muscovy ducks. In addition to the lesions observed in the geese, muscle fibre degeneration, mild sciatic neuritis and polioencephalomyelitis were also observed in the Muscovy ducks infected with any of the three parvovirus strains.