H5亚型禽流感疫苗对特禽及水禽的免疫效果观察

用H5N2亚型禽流感疫苗,分别免疫SPF鸡、乌鸡、珍珠鸡、贵妃鸡、火鸡、鸭及鹅,免疫后采血测定其HI抗体,观察我国现有的H5N2亚型禽流感疫苗对特禽及水禽的免疫效力.结果,免疫后3周,SPF鸡、乌鸡、珍珠鸡、贵妃鸡、火鸡、鸭及鹅的平均HI抗体滴度分别为2 7.2、2 7.6、2 4.3、2 4.83、2 4.6、2 6.2及2 5.3,乌鸡两次免疫,其中一次HI抗体为2 9.65.试验证明,SPF鸡、特禽及水禽用H5N2亚型禽流感疫苗免疫后,均能产生一定水平的HI抗体,但不同种类的家禽所产生的HI抗体滴度存在较大差异,以SPF鸡及乌鸡所产生的HI抗体滴度最高,而珍珠鸡、贵妃鸡及火鸡所产生的HI抗体滴度较低,水禽对H5N2亚型禽流感疫苗可产生一定水平的HI抗体.     

The status of guinea fowls (Numida meleagris) in the epidemiology of infectious bursal disease (IBD) of poultry in Nigeria

A serological survey for IBD in market guinea fowls gave a total prevalence rate of 44.3% from five different locations in Nigeria. Guinea fowl keets were susceptible to experimental IBD infection and transmitted it to in-contact sentinel chickens. The infected guinea fowl keets showed the typical clinical-pathology and seroconversion for IBD. These results suggest that guinea fowls could play an active part in the epidemiology of IBD.     

Studies on the response of guinea fowls (Numida meleagris) to antibiotics

1. The response of growing male guinea fowls to dietary supplements of oxytetracycline, Roxarsone and zinc bacitracin were investigated. 2. The antibiotics produced significant increases in body weight, efficiency of food utilisation and nitrogen retention in guinea fowls at 12 weeks of age. 3. Carcase protein was not affected by antibiotic supplementation but carcase dry matter and fat were significantly higher in guinea fowls receiving medicated food than in controls. 4. The results show that the growth rate of guinea fowls is significantly increased by similar inclusion rates of oxytetracycline, Roxarsone and zinc bacitracin as those generally recommended for broiler chickens.     

甘肃省特禽疫病的流行病学调查

在甘肃省60个特种禽类养殖场,采集了17个品种禽类的非免疫血清953份、免疫血清51份、脏器等病料83份,进行了实验室检验和监测,结果表明鸽感染了ND、A I、IB、ILT、AL、FP、IBD 7种疫病,鸭感染ND、A I、ILT、FP、VA、PD 6种疫病,鹧鸪感染了A I、IB、ILT、IBD 4种疫病,珍珠鸡感染了IB、ILT、AL 3种疫病,鸵鸟感染了ND,乌鸡感染了IB、ILT、IBD、M D、VA、IC,贵妇鸡感染了M D、AL、IC。从病料中检出了大肠杆菌、都柏林沙门氏菌和念珠菌、组织滴虫和球虫虫卵等病原。ND、A I、IB、IBD、ILT、FP 6种疫病的免疫抗体水平普遍较低。     

不同禽类核型似近系数聚类分析

对北京油鸡和金定鸭染色体核型进行了研究。结果表明:北京油鸡和金定鸭常染色体形态存在较大差异,北京油鸡的No.4、No.6和No.8染色体分别为st、sm型和m型染色体;而金定鸭的No.4、No.6和No.8染色体均为t型染色体;北京油鸡的Z、W染色体为m型染色体;而金定鸭的Z和W染色体分别为st型和t型染色体。此外,核型似近系数和进化距离聚类分析表明6种禽类可分为3类,Ⅰ类包括金定鸭和五龙鹅;Ⅱ类包括鹌鹑、石鸡和北京油鸡;而稚鸡单独成类,其结果与形态分类学和系统分类学大致相同。     

Egg-drop syndrome 76 in Danish poultry.

After a more general mention of Egg drop Syndrome 76 (EDS 76) an account is given of 3 cases of EDS 76 in broiler parent flocks. In all cases the animals involved originated from Ireland and were imported as day-olds, either directly from Ireland or via Sweden. Serological examinations indicate that the infectious agent has not previously been present in Danish hen flocks, but that it is presumably stationary in Danish flocks of ducks. In 2 of the 3 cases of EDS 76 animals from 2 different foreign firms were involved, and everything indicates that the infection has been carried by chickens from one of the firms and spread horizontally to the other. In the first case 12 weeks lapsed from the first to the last of 6 flocks in the same locality were attacked by SDS 76. An example is also given of trans-ovarial spread of EDS 76-virus to broiler flocks which at the age of 10--20 days were attacked by a disease similar to gangrenous dermatitis. In the course of the following few weeks an intensive rise took in the frequency of positive reaction to EDS 76. It is assumed that the EDS 76-virus has been of importance to the development of the said disease in these broiler flocks.     

Pasteurella gallinarum: Zimbabwean experience of a versatile pathogen

Pasteurella gallinarum-related outbreaks in chickens and African guinea fowls are described. Four outbreaks were recorded in chickens and one in guinea fowls. Periorbital swelling and keratoconjunctivitis were the consistently present clinical signs in all the diseased birds. In several, swollen hocks and wattles were also discerened. Birds which succumbed to the infection showed petechiation in the internal organs and evidence of airsacculitis. Pasteurella gallinarum was isolated from the lesions and also from conjunctival swabs of the apparently healthy in-contact birds. There was no evidence of concurrent infection with Haemophilus, Mycoplasma or Chlamydia. Quinolone therapy when resorted to on one of the farms resolved the clinical signs. Phenotypes of 28 isolates were studied. The results compared well with the Pasteurella gallinarum isolates reported earlier from elsewhere. It was also found that results of xylose fermentation and ONPG test appear to be a variable character. There is no earlier report of P. gallinarum infection in guinea fowls.     

The influence of gender and group membership on food safety: the case of meat sellers in Bodija market,Ibadan, Nigeria

Four Newcastle disease virus isolates were recovered from asymptomatic guinea fowl (Numida meleagris galeata) and Muscovy ducks (Cariana moscata). For the purpose of molecular identification and phylogeny, phylogenetic characterization was performed to identify the pathotypes. All four viruses had a cleavage motif ¹¹²RRQKRF¹¹⁷ which is characteristic of virulent strains. The isolates grouped with viruses previously reported as sub-lineage 5g from chickens in Nigeria. This study report for the first time the identification of the virulent sub-lineage 5g Newcastle disease virus from apparently healthy guinea fowl and domestic ducks in Nigeria, and since infections were sub-clinical, it suggest that these species could play a role in the spread and transmission of virulent Newcastle disease virus that can infect other poultry. The isolation and identification of virulent Newcastle disease virus in these unusual hosts and the high sequence similarity (99.3–100 %) between viruses in this study with strains reported for Niger and Cameroun gives insights into the ecology of virulent Newcastle disease viruses and suggests some cross-border movement and trade in live poultry.     

Physical and chemical properties of meat from scavenging chickens and helmeted guinea fowls in response to age and sex

1. The effects of age and sex on body weight, carcass traits, physical and chemical properties of breast muscle from chickens and helmeted guinea fowls managed under village free-range conditions were assessed in random samples of 48 guinea fowls and 48 chickens obtained from local markets.

2. Guinea fowls had higher body weight, hot carcass weight, cold dressed weight and breast weight than chickens.

3. Guinea fowls had more dry matter, protein and less fat than chickens. Ash content did not differ between guinea fowls and chickens. Protein and fat increased, whereas dry matter and ash decreased with age (P < 0.05)

4. Chicken meat was lighter, less red and more yellow than guinea fowl meat. Cooking loss was higher in guinea fowls, male and grower birds than chickens, females and adult birds, respectively. Shear force was affected by age, as mature birds had a higher value than growers.

5. Guinea fowl carcasses contained more meat that was leaner, higher in protein and redder compared with chicken meat. As age increased the meat increased in protein and fat content and shear force, whereas colour became darker, redder and yellower.     

Review of the literature on avian influenza A viruses in pigeons and experimental studies on the susceptibility of domestic pigeons to influenza A viruses of the haemagglutinin subtype H7

The scientific literature of the past century is reviewed on fowl plague (presently termed highly pathogenic avian influenza, HPAI) in pigeons. HPAI viruses cause epidemic disease outbreaks with high rates of losses in many avian species, particularily in chickens and turkeys. Also susceptible to disease are quails, guinea fowl, ducks, geese, ostriches, passerine birds, and birds of prey whereas conflicting reports on the susceptibility of the domestic pigeon exist. Based on literature reports and on own experiments, and applying as criteria for judgements clinically overt forms of disease, virus multiplication plus shedding and seroconversion, it is concluded that domestic pigeons are only partially susceptible to influenza A viruses of the haemagglutinin subtype H7. Infection of pigeons with H7 viruses results only in some of them in signs, virus shedding and seroconversion. Using the same criteria, pigeons appear to be even less susceptible to infection with influenza A viruses of the H5 subtype. Only one of five publications describe in 1/19 pigeons exposed to H5 influenza A virus depression one day before death, and only 2/19 multiplied and excreted virus, and 1/19 developed circulating antibodies. Consequently, pigeons play only a minor role in the epidemiology of H5 influenza viruses. In contrast, following infection with influenza A virus of the subtype H7 clinical signs in pigeons consist of conjunctivitis, tremor, paresis of wings and legs, and wet droppings. H7-infected pigeons multiply and excrete H7 viruses and develop circulating antibodies. Albeit of the status of infection, free-flying domestic pigeons can act as mechanical vectors and vehicles for long-distance transmission of any influenza A virus if plumage or feet were contaminated.     

EDS 76 HI antibodies in a flock of free-range layers

An investigation of poor laying performance in a flock of free-range hens revealed high levels of serum antibodies to EDS 76 in the flock initially examined and in another, older flock on the same farm. These flocks had contact with ducks on a farm dam and were supplied with untreated drinking water from the dam. Serological evidence indicated that another flock supplying the same egg packing station had been infected with EDS 76 virus. Little serological evidence of EDS infection was detected from five other flocks supplying the packing station, parent breeders or the ducks resident on the dam. Therefore, the source of the EDS 76 virus remains conjectural.     

Putative protective antibody response following oral vaccination of multi-age free ranging helmeted guinea fowls (<Emphasis Type="Italic">Numida meleagris</Emphasis>) with Newcastle disease virus strain I-2 coated on oiled rice

On-farm study was conducted to determine the efficacy of thermostable Newcastle disease (ND) strain I-2 vaccine coated on oiled rice following oral vaccination of multi-age free ranging helmeted guinea fowls. The results from haemagglutination-inhibition assay showed that 7 days after the guinea fowls were orally vaccinated they seroconverted and attained the geometric mean antibody titre (GMT) of 4.9 log₂ (80%). This antibody titre was above the GMT of 3.0 log₂ which is regarded to be protective against field challenge of ND. Furthermore, the results revealed that 28 days after vaccination, the antibody levels reached GMT of 7.6 log₂ (100%). Moreover, all vaccinated guinea fowls survived the challenge of virulent ND virus whereas all unvaccinated chickens died of ND. The findings from the present study showed that the I-2 virus coated on the oiled rice is safe, immunogenic and provoked production of protective antibody response following oral vaccination of helmeted guinea fowls.     

非典型鸡新城疫在尼日内亚西北地区的流行和防治

笔者实地调查了解了目前在尼日利亚西北地区散发流行的非典型鸡新城疫的发病情况并参与了诊断与防治工作。认为免疫不当、野毒不断侵袭、鸡群免疫力低是当地发病的基本原因。症状不典型,发病季节不明显,病鸡持续零星死亡,并且在已打过ND疫苗的鸡群仍然发病是本病在当地的流行特征。文章还反映了中尼人员合作采取的综合性的谤治措施。     

禽黄病毒套式RT-PCR检测方法的建立及应用

禽黄病毒病是新发的一种疫病,可引起鸭、鹅和鸡等家禽产蛋和采食量下降及死亡。本研究旨在建立一种快速诊断方法用于临床诊断及流行病学调查。根据GenBank发表的鹅黄病毒JS804株全基因序列,应用Primer Premier 5.0软件设计了2对特异性引物,建立了禽黄病毒套式RT-PCR检测方法。结果:该套式RT-PCR方法具有特异性强、敏感性高的特点,最低病毒检测量为101.89TCID50/0.1 mL,比普通RT-PCR方法敏感性高1 000倍。应用该方法对江苏地区疑似禽黄病毒病的70份鹅病料、4份鸭病料、12份鸡病料进行检测,总阳性率为58.14%,而用普通RT-PCR方法检测的阳性率仅为17.44%。结果表明,禽黄病毒套式RT-PCR检测方法具有快速、特异、敏感的特点,可用于禽黄病毒感染的临床诊断和流行病学调查。     

鸭源流感病毒感染对鸡和家鸭红细胞免疫功能的影响

采用商品来航鸡、樱桃谷鸭分别接种鸭源流感病毒株Ａ／ｄｕｃｋ／Ｎａｎｊｉｎｇ／２１／９５（Ｈ９Ｈ？），研究了禽流感病毒（ＡＩＶ）感染对红细胞免疫功能的影响。结果发现，流感发生与红细胞ＣＲ１花环率之间存在着反向关系；正常鸭的红细胞ＣＲ１花环率极显高于正常鸡的红细胞ＣＲ１花环率，即使接种ＡＩＶ后，鸭红细胞ＣＲ１花环率有所下降，但也显著高于正常鸡的红细胞ＣＲ１花环率，这些结果表明，鸭的红细胞免疫功能在一定     

Egg drop syndrome '76 in Bolivia

Summary Four outbreaks of Egg Drop Syndrome '76 (EDS '76) were diagnosed between April 1993 and July 1993 in the Santa Cruz Department of Bolivia, around the department capital Santa Cruz. Three outbreaks involved commercial laying birds and the fourth a broiler breeder unit. Clinical signs were typical of EDS '76 with decreases in egg production of up to 55% being recorded as well as the production of thin shelled and shell-less eggs. A total of 183 serum samples from the 4 farms were tested for the presence of antibodies to the EDS '76 virus using a haemagglutination inhibition test, with titres of 16 or above being considered as a positive result. Of 63 samples from groups of birds showing signs of EDS '76, 58 (92·1%) had positive titres, and 88 out of 90 samples (97·8%) from unaffected groups of birds had negative titres. Out of 30 samples from birds not yet in lay from the affected farms 28 (93·3%) had titres below 16.EDS '76 had not been reported in Bolivia prior to these outbreaks and vaccination was not practised. The most probable source of virus was from day old chicks imported from South American countries which had recorded outbreaks of EDS '76 before April 1993. The source of the virus, its spread and the control measures implemented in the Santa Cruz area are discussed.

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Sindrome De Caida De La Puesta '76 En Bolivia

Resumen Entre abril de 1993 y julio de 1993 se diagnosticaron 4 brotes de síndrome de caida de la puesta '76 (EDS '76) en el departamento de Santa Cruz de Bolivia, y más concretamente en los alrededores de la capital del departamento, Santa Cruz. Tres brotes afectaron a naves comerciales de ponedoras y el cuarto afectó a una granja de reproductoras tipo carne. Los síntomas fueron los característicos de EDS '76, con disminuciones en la puesta de hasta el 55% y producción de huevos sin cáscara o con la cáscara muy delgada. Un total de 183 muestras de suero procedentes de las 4 granjas fueron sometidas a una prueba de inhibición de la hemoaglutinación con objeto de detectar anticuerpos frente al virus de la EDS '76. Un título igual o superior a 16 se consideró positivo. De las 663 muestras procedentes de animales con signos clínicos, 58 (92·1%) fueron positivas, mientras que 88 de las 90 muestras (97·8%) de animales clínicamente sanos fueron negativas. De las 30 muestras procedentes de aves que noe estaban en puesta todavía pero procedían de granjas afectadas por la enfermedad, 28 (93·3%) fueron negativas.El EDS '76 no había sido diagnosticado en Bolivia anteriormente y no se realizaban vacunaciones para prevenirlo. Probablemente, el virus fue introducido al importar pollitos de un día de países sudamericanos que sufrieron brotes de EDS '76 antes del mes de abril de 1993. Se discuten la fuente del virus, su diseminación y las medidas de control implementadas en Santa Cruz.

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Egg Drop Syndrome '76 En Bolivie (EDS '76-Infection De l'Oviducte Par Des Adenovirus Causant Une Fragilite Des Coquilles d'Oeuf)

Résumé Quatre épidémies liées à l'EDS '76 furent diagnostiquées entre Avril 1993 et Juillet 1993 dans le départment de Santa Cruz en Bolivie, autour de la capitale de Santa Cruz. Trois épidémies impliquèrent des productions de poules pondeuses et la quatrième une unité de poulets à rotir. Les signes cliniques furent typiques de l'EDS '76 avec la diminution de la production d'oeufs jusqu'à 55% ainsi que la production d'oeufs à coquilles plus fine ou en moins grande quantité. 183 serums provenant des 4 fermes furent testés pour la présence d'anticorps contre le virus de l'EDS '76 utilisant un test d'inhibition de l'hémo-agglutination, les titres au dessus ou égaux à 16 furent considérés comme positif. Sur les 63 échantillons provenant du groupe des oiseaux avec les signes de d'EDS '76, 58 (92,1%) eurent des titres positifs et sur les 90 oiseaux du groupe non-infectés, 88 (97,8%) eurent des titres négatifs. Sur les 30 oiseaux pas encore pondeurs provenant des fermes contaminées, 28 (93,3%) eurent des titres inférieurs à 16. L'infection par l'EDS '76 n'avait pas été signalé en Bolivie avant ces épidémies et la vaccination ne fut pas pratiquée. La source la plus probable de contamination proviendrait de poussins agés d'un jour et provenant de pays d'Amèrique du Sud où des épidemies de EDS '76 furent signalées avant Avril 1993. La source du virus, sa dissémination et les mesures de contrôle implantées dans la région de Santa Cruz sont discutées.

     

The pathogenicity of four avian influenza viruses for fowls, turkeys and ducks

Groups of 10 two-week-old chicks, turkey poults and ducklings were each infected by the intranasal route with one of four avian influenza viruses: a/fowl/Germany/34 (Hav 1N))--Rostock, A/FPV/Dutch/27 (Hav 1 Neq 1)--Dutch, A/fowl/Victoria/75 (Hav 1 Neq 1)--Australian, and A/parrot/Ulster/73 (Hav 1 N1)--Ulster. Eight hours after infection 10 birds of the same age and species were placed in contact with each group and allowed to mix. The clinical signs of disease and onset of sickness and death were recorded. Ulster virus was completely avirulent for all birds. Rostock, Dutch and Australian viruses were virulent for fowls and turkeys causing death in all birds with the exception of 3/10 in contact fowls from the Rostock virus group and 2/10 in contact fowls from the Australian virus group. Only Rostock virus caused sicked sickness or death in ducks, 9/10 intranasally infected and 6/7 in contact birds showed clinical signs and 2/10 intranasally infected and 3/7 in contact ducks died. Intranasal and in contact pathogenicity indices were calculated for each virus in each bird species and indicated quantitatively the differences in virulence of the four virus strains. Virus isolation and immune response studies indicated that surviving in contact fowls in the Rostock virus group had never been infected but that surviving Australian virus in contact fowls had recovered from infection. Infection was not established in Ulster virus in contact fowls and Australian virus intranasally infected and in contact ducks. The birds in all other groups showed positive virus isolations and a high incidence of positive immune response. The last virus isolation was made at 22 days after intranasal infection of ducks with Ulster virus.     

Seroprevalence of egg drop syndrome - 76 virus as cause of poor egg productivity of poultry in Nsukka,South East Nigeria

To determine if egg drop syndrome 76 virus infection is among the causes of lowered egg productivity in commercial poultry farms in South Eastern Part of Nigeria and to know the prevalence of the infection, ten farms with history of lowered egg production in Nsukka local government area of Enugu State were randomly selected. Sera from ten hens in each of the selected farms were assayed for antibodies against EDS 76 virus by the haemagglutination-inhibition (HI) test. The mean HI titre of the ten hens in each of the farms was recorded as EDS - 76 antibody titre for the farm. Nine out of the 10 farms tested were positive for EDS - 76 antibodies with HI titres ranging between 16 and 256. Out of 10 flocks with production of 65% and above 9 were EDS-76 HI negative.     

Experimental eosinophilia in domestic fowls and ducks following horse serum stimulation

Multiple intraperitoneal injections of horse serum given to domestic fowls at five different ages resulted in eosinophilia in 55% of adults and in 36% of the younger birds, the highest individual eosinophil level reached being 50% of the differential white cell count. The primary eosinophilic response in fowls was between injections 7 and 36 and there was a secondary response between injections 32 and 72.Horse serum injections produced an eosinophilia in 88% of adult ducks with a maximum individual level of 31% of the differential white cell count. In ducks, primary and secondary eosinophilic responses occurred at injections 13 and 28 respectively.