Egg transmission of egg drop syndrome 1976 virus in fowl

Summary

Egg transmission of egg drop syndrome 1976 virus (BC14 virus) in fowl was demonstrated in the second and third week after experimental infection. Eggs of BC14 virus infected hens were incubated weekly after disinfection with formaline gas. After 18 days of incubation, eggs with live embryos were homogenized. This egg material was fed to adult hens, housed in isolators.

Seroconversion in these birds demonstrated egg transmission.

It is suggested that egg transmission occurs as a result of viremia.     

Egg transmission of egg drop syndrome 1976 virus in fowl

Summary Egg transmission of egg drop syndrome 1976 virus (BC14 virus) in fowl was demonstrated in the second and third week after experimental infection. Eggs of BC14 virus infected hens were incubated weekly after disinfection with formaline gas. After 18 days of incubation, eggs with live embryos were homogenized. This egg material was fed to adult hens, housed in isolators. Seroconversion in these birds demonstrated egg transmission. It is suggested that egg transmission occurs as a result of viremia.     

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.

     

No evidence for adaptation of current egg drop syndrome 1976 viruses to chickens

In order to determine whether the current field strains of egg drop syndrome (EDS) 1976 viruses adapt to chickens, we compared the growth efficiency of three Japanese field strains (PA-1/79, AWI/98, Gifu/01) in chicken and duck embryo liver cells. The growth efficiency in chicken or duck embryo liver cells was almost similar in these strains. The fiber protein may carry the type-specific antigen and the hemagglutination activity, and hexon protein may contain the subgroup-specific antigenic determinants. Therefore, the fiber head and hexon loop 1 DNA domain sequences of the six Japanese field strains UPA-1/79, ME/80, 44/81, Kyoto/91, AWI/98, Gifu/01) were compared, but these DNA domains were identical among the six field strains. Our data suggested that the EDS virus was maintained without discernible changes for the last two decades in the field.     

鸡产蛋下降综合征病毒内蒙分离株的生物学特性研究

对鸡产蛋下降综合征病毒内蒙古地区分离株进行了生物学特性测定和血清学鉴定,结果表明,Ｂ４、Ｎ３株与１２７株均能抵抗乙醚、氯仿和胰蛋白酶,而在对酸、碱、温度及甲醛的稳定性测定中,Ｎ３株ＥＤＳ７６病毒对这些因素抵抗力强于Ｂ４株和１２７株,而Ｂ４株和１２７株ＥＤＳ７６病毒对这些因素的抵抗力基本相同,说明不同ＥＤＳ７６病毒株间理化特性上存在有差异。血清学试验结果表明,Ｂ４、Ｎ３株与１２７株ＥＤＳ７６病毒的血清学关系非常相近。     

Egg drop syndrome '76 in poultry and other avian species in Nigeria.

A sero-epidemiological survey of EDS '76 antibodies was carried out in chickens, guinea fowls, ducks and pigeons in various locations in Nigeria with the haemagglutination-inhibition test. Infection rates of 67.43, 79.68, 73.91 and 86.66% were obtained for chickens, guinea fowls, ducks and pigeons respectively. The high prevalence rates observed in these non-chicken species suggest that they should be considered as important in the epidemiology of EDS '76 in poultry in Nigeria. An extensive survey is recommended together with vaccination.     

银加强胶体金探针检测鸡减蛋综合征病毒的研究

本研究首镒报道应用银加强胶体金探针检测减蛋综合征病毒获得成功。经初步提纯后的ＥＤＳ７６病毒免疫制备高免血清，按常规方法提取兔抗ＥＤＳ７６病毒的ＩｇＧ，成功地建立了检测ＥＤＳ７６病毒抗原的银加强胶体金探针法，并确定了操作程序的最佳试验条件为；兔抗ＥＤＳＶＩｇＧ工作浓度为１：４００，金标记羊抗兔ＩｇＧ的工作浓度为１：２０，银染色的时间为１５ｍｉｎ。用该法对提纯的ＥＤＳ７６病毒抗原的最低检出一为０．１１     

Serological examination and egg production of progeny of fowl experimentally infected with Egg Drop Syndrome 1976 virus

Summary

Following EDS'76 virus (BC14 virus) infection of breeder chickens by the conjunctival route, vertical transmission occurred in the first week after infection. In the progeny which had been infected with EDS'76 virus by the vertical route, increasing haemagglutination inhibiting (HI) litres to BC14 virus and increasing numbers of birds with HI litres were observed from 3 weeks to 15 weeks of age. Sixty‐one per cent of the hens and 77 per cent of the cocks had ²log HI BC14 virus litres exceeding 4 at an age of 15 weeks.

Some birds which had been serologically negative throughout the rearing period, seroconverted between 25 and 28 weeks of age. This phenomenon occurred in hens as well as in cocks. Simulation of stress twice during the laying period by injection of corticosteroid hormone did not increase the number of birds serologically positive to EDS'76 virus.

EDS'76 was observed in the group of hens that was vertically infected, since egg production was significantly depressed between 28 and 34 weeks of age. Probably this was mainly the result of a production drop in the hens showing seroconversion at 27 or 28 weeks of age.

In the group of fowl vertically infected with EDS'76 virus, serologically positive birds appeared to be protected for the greater part to BC14 virus challenge at 50 weeks of age, while negative birds seemed to be fully susceptible. Chicks hatched from eggs collected in the third and fourth week after infection of the dams had maternal antibodies. Fertility and hatchability of apparently normally shelled eggs seemed not to be affected after BC14 virus infection of the dams. Intensive contact with contaminated faeces is probably an indispensable condition for lateral transmission of the virus.     

Serological examination and egg production of progeny of fowl experimentally infected with egg drop syndrome 1976 virus

Following EDS'76 virus (BC14 virus) infection of breeder chickens by the conjunctival route, vertical transmission occurred in the first week after infection. In the progeny which had been infected with EDS'76 virus by the vertical route, increasing haemagglutination inhibiting (HI) titres to BC14 virus and increasing numbers of birds with HI titres were observed from 3 weeks to 15 weeks of age. Sixty-one per cent of the hens and 77 per cent of the cocks had 2 log HI BC14 virus titres exceeding 4 at an age of 15 weeks. Some birds which han been serologically negative throughout the rearing period, seroconverted between 25 and 28 weeks of age. This phenomenon occurred in hens as well as in cocks. Simulation of stress twice during the laying period by injection of corticosteroid hormone did not increase the number of birds serologically positive to EDS'76 virus. EDS'76 was observed in the group of hens that was vertically infected, since egg production was significantly depressed between 28 and 34 weeks of age. Probably this was mainly the results of a production drop in the hens showing serconversion at 27 or 28 weeks of age. In this group of fowl vertically infected with EDs'76 virus, serologically positive birds appeared to be protected for the greater part to BC14 virus challenge at 50 weeks of age, while negative birds seemed to be fully susceptible. Chicks hatched from eggs collected in the third and fourth week after infection of the dams had maternal antibodies. Fertility and hatchability of apparently normally shelled eggs seemed not to be affected after BC14 virus infection of the dams. Intensive contact with contaminated faeces is probably an indispensable condition for lateral transmission of the virus.     

间接法Dot—ELISA检测鸡减蛋综合症抗体的建立及应用研究

应用ＳｅｐｈａｄｃｘＧ－２００层析法纯化鸡减蛋综合症病毒，利用ＮＣ膜作为载体，成功建立了检测ＥＤＳ－７６血请抗体的斑点酶联免疫吸附试验（Ｄｏｔ－ＥＬＩＳＡ）。抗原包被浓度为２μｇ／ｍｌ，被检血清浓度为１：２０，酶标兔抗鸡１ｇＧ浓度为１：２００．底物溶液最适ｐＨ值为７．２。对Ａ－Ｆ６个养禽场随机抽检血清１６０份，分别用Ｄｏｔ－ＥＬＩＳＡ、ＨＩ和ＡＧＰ检测，Ｄｏｔ－ＥＬＩＳＡ检出阳性率为５１．９％，ＨＩ检出阳性率为４６．９％，ＡＧＰ检出阳性率为３１．９％。对１４０日龄鸡人工感染试验，测定抗体消长规律。本方法不需特殊仪器。适用于基层兽医部门和养鸡场对ＥＤＳ－７６的血清学诊断和流行病学调查。     

Restriction Enzyme Analysis of Indian Isolates of Egg Drop Syndrome 1976 Virus Recovered from Chicken,Duck and Quail

Egg drop syndrome 1976 (EDS-76) is caused by a haemagglutinating adenovirus belonging to group III of the genus Aviadenovirus in the family Adenoviridae. All isolates are serologically identical, but have been divided into three groups based on restriction endonuclease (RE) analysis. In this study the viral DNA of various Indian EDS-76 viral isolates (CEDS-A, CEDS-B, EDS-M, EDS-ML, EDS-1/AD/86, EDS-KC and QEDS) obtained from different avian species and different geographical regions were digested with restriction endonucleases viz., EcoRI, BamHI, HindIII and PstI. The results showed that one Indian isolate obtained from duck (DEDS-KC) was different from all other chicken and quail counterparts. All other isolates were identical to the reference viral strain BC-14, which belong to group I of EDS-76 viruses. The duck isolate EDS-KC could not be placed in any of the three groups reported earlier.     

蛋类及蛋制品的鉴别

1 蛋及蛋制品的感官鉴别要点 　　鲜蛋的感官鉴别分为蛋壳鉴别和打开鉴别.蛋壳鉴别包括眼看、手摸、耳听、鼻嗅等方法,也可借助于灯光透视进行鉴别.打开鉴别是将鲜蛋打开,观察其内容物的颜色、稠度、性状、有无血液、胚胎是否发育、有无异味和臭味等.……     

对富含ω-6多不饱和脂肪酸鸡蛋的研究

将60只52周龄蛋鸡分为五组,对照组饲喂基础日粮,试验组分别饲喂含3%胡麻油,3%菜籽油,3%大豆油和3%花生油的日粮,研究日粮中添加植物油对鸡蛋中ω-6多不饱和脂肪酸的影响。结果表明,日粮中添加3%植物油可明显提高蛋鸡生产性能和增加蛋中亚油酸(C18∶2)的含量(P<0.05),在20、30d和40d收集的鸡蛋蛋黄中,试验组的亚油酸(C18∶2)含量明显高于对照组(P<0.05);试验3组提高幅度最高(20、30、40d分别比对照组提高20.9%、54.0%、57.2%),试验2组提高幅度最低(20、30、40d分别比对照组提高5.3%、11.3%、23.7%)。     

Spinal lymphoma in cats: 21 cases (1976-1989).

Medical records of 21 cats with spinal lymphoma were reviewed. All cats were evaluated for neurologic deficits, although 85% of cats necropsied had multicentric disease. Eighty-one percent of cats had hind limb paresis. Results of FeLV tests were positive in 84.2% (16/19) of the cats, and 68.7% (11/16) of the cats had leukemic bone marrow. Spinal lymphoma was confirmed by necropsy in 13 cats, by examination of a biopsy specimen in 1 cat, and by examination of cells aspirated from an epidural lesion in 2 cats. In the remaining 5 cats, a presumptive diagnosis was made on the basis of neurologic examination findings, positive FeLV test results, and leukemic bone marrow. Nine cats were treated with chemotherapy alone. The complete remission rate was 50% in 6 cats given cyclophosphamide, vincristine, and prednisone. The median duration of complete remission was 14 weeks. Complete remissions were not observed in 3 cats given only corticosteroids. A single cat treated by laminectomy and postoperative chemotherapy had a prolonged remission (62 weeks). At necropsy, lymphoma of the CNS was limited to the vertebral canal in 10 of 13 cats; 2 cats had malignant tissue in the brain and vertebral canal, and in the remaining cat, the tumor extended into the brachial plexus. Most tumors extended over multiple vertebral bodies, and 4 cats had more than 1 level of spinal cord involvement. The lymphoma was high-grade lymphoblastic or immunoblastic type in all cats.