Experimental avian paramyxovirus serotype-3 infection in chickens and turkeys

Avian paramyxoviruses (APMV) are divided into nine serotypes. Newcastle disease virus (APMV-1) is the most extensively characterized, while relatively little information is available for the other APMV serotypes. In the present study, we examined the pathogenicity of two divergent strains of APMV-3, Netherlands and Wisconsin, in (i) 9-day-old embryonated chicken eggs, (ii) 1-day-old specific pathogen free (SPF) chicks and turkeys, and (iii) 2-week-old SPF chickens and turkeys. The mean death time in 9-day-old embryonated chicken eggs was 112 h for APMV-3 strain Netherlands and > 168 h for strain Wisconsin. The intracerebral pathogenicity index in 1-day-old chicks for strain Netherlands was 0.39 and for strain Wisconsin was zero. Thus, both strains are lentogenic. Both the strains replicated well in brain tissue when inoculated intracerebrally in 1-day-old SPF chicks, but without causing death. Mild respiratory disease signs were observed in 1-day-old chickens and turkeys when inoculated through oculonasal route with either strain. There were no overt signs of illness in 2-weeks-old chickens and turkeys by either strain, although all the birds seroconverted after infection. The viruses were isolated predominantly from brain, lungs, spleens, trachea, pancreas and kidney. Immunohistochemistry studies also showed the presence of large amount of viral antigens in both epithelial and sub-epithelial lining of respiratory and alimentary tracts. Our result suggests systemic spread of APMV-3 even though the viral fusion glycoprotein does not contain the canonical furin proteases cleavage site. Furthermore, there was little or no disease despite systemic viral spread and abundant viral replication in all the tissues tested.     

Comparative pathogenicity tests of eight pigeon paramyxovirus 1 variant isolates in pigeons, turkeys and chickens]

Eight pigeon paramyxovirus-1 isolates which were isolated from diseased pigeons were comparatively tested for their pathogenicity in chickens, turkeys and racing pigeons. Intramuscular inoculation of all of the eight viruses resulted in all pigeons in clinical signs like polyuria, lameness of wings and in parts also in torticollis. Also, intravenously inoculated chickens developed distinct signs such as apathy, liquid droppings and in part also torticollis. Six of the eight PMV-1 isolates induced in turkeys similar signs as in chickens; inoculation of two isolates yielded no signs in turkeys. Legal sanitary consequences of the disease due to pigeon PMV-1 infection in chickens and in turkeys should be identical to that of velogenic Newcastle disease.     

Pathogenesis of two strains of avian paramyxovirus serotype 2, Yucaipa and Bangor, in chickens and turkeys

Nine serologic types of avian paramyxovirus (APMV) have been recognized. Newcastle disease virus (APMV-1) is the most extensively characterized virus, while relatively little information is available for the other APMV serotypes. In the present study, we examined the pathogenicity of two strains of APMV-2, Yucaipa and Bangor, in 9-day-old embryonated chicken eggs, 1-day-old specific-pathogen-free (SPF) chicks, and 4-wk-old SPF chickens and turkeys. The mean death time in 9-day-old embryonated chicken eggs was more than 168 hr for both strains, and their intracerebral pathogenicity index (ICPI) was zero, indicating that these viruses are nonpathogenic in chickens. When inoculated intracerebrally in 1-day-old chicks, neither strain caused disease or replicated detectably in the brain. This suggests that the zero ICPI value of APMV-2 reflects the inability of the virus to grow in neural cells. Groups of twelve 4-wk-old SPF chickens and turkeys were inoculated oculonasally with either strain, and three birds per group were euthanatized on days 2, 4, 6, and 14 postinoculation for analysis. There were no overt clinical signs of illnesses, although all birds seroconverted by day 6. The viruses were isolated predominantly from the respiratory and alimentary tracts. Immunohistochemistry studies also showed the presence of a large amount of viral antigens in epithelial linings of respiratory and alimentary tracts. There also was evidence of systemic spread even though the cleavage site of the viral fusion glycoprotein does not contain the canonical furin protease cleavage site.     

Fox encephalitozoonosis: isolation of the agent from an outbreak in farmed blue foxes (Alopex lagopus) in Finland and some hitherto unreported pathologic lesions

The farmed blue fox (Alopex lagopus) is particularly susceptible to congenital infections of the microsporidian species Encephalitozoon cuniculi. This report is based on an outbreak of the disease in Finland with high mortality. Five pups (four males and one female) with prolonged disease were examined. The pups had moderate pathological alterations in the kidneys and mild lesions were found in the brains, hearts, salivary and prostatic glands. Diagnosis of E. cuniculi infection was made from serological tests (ELISA, CIA, IFAT), and by in vitro isolation of the parasite from the brain of all five pups investigated. The identity was confirmed by molecular means as E. cuniculi strain II ('mouse strain'). Novel histopathological lesions not described as yet in fox encephalitozoonosis are presented. These include cerebral infarction and necrotizing inflammation of the renal pelvis. The sources and mechanisms of spreading of E. cuniculi to blue foxes are discussed.     

鸭源副黏病毒的致病性试验

利用鸭源副黏病毒(DPMV)SDFC株分别人工感染21日龄健康非免疫樱桃谷肉鸭和SPF雏鸡,观察试验鸡、鸭的发病情况及临床症状,于感染后不同时间剖杀,观察各组织器官的病理变化,并进行病理组织学研究。结果显示,鸭感染DPMV后发病率为100%,死亡率为43.3%;而鸡感染后的发病率、死亡率均为100%。病理组织学研究结果显示,鸭感染DPMV后,以心脏、肺脏、肝脏、肾脏、脾脏、法氏囊广泛性出血、变性为特征,消化道病变较轻微;而鸡感染DPMV后,各组织器官广泛性出血,脾脏、胸腺、法氏囊、肝脏、胰腺、肾脏、心肌组织细胞出现不同程度的变性、坏死;食管、腺胃和各段肠管广泛性出血,并伴有黏膜脱落。结果表明,DPMV对鸡、鸭均有较强的致病性,而与鸡相比,对鸭的致病性较弱。     

A case of salinomycin intoxication in turkeys

A flock of 4287 heavy hybrid turkey hens were accidentally fed broiler premix containing salinomycin sodium and suffered a 34.5% death loss. Measures taken to ensure food safety for the remaining flock and consumer food safety included feed record studies, on-farm veterinary consultation, diagnostic laboratory studies, and CgFARAD and CFIA consultation. The remaining turkeys were processed 3 weeks after the initial toxicosis with no evidence of lesions that would render the product unfit for human consumption.     

Vitamin A requirement for growing turkeys

The vitamin A requirement of Broad Breasted White turkey poults from o to 12 weeks of age is at least 2670 i.u. vitamin A/kg and possibly ranges between 2670 and 4721 i.u. vitamin A/kg.

The vitamin A stored in the liver of the turkeys fed 4721 i.u. vitamin A/kg was significantly greater than those fed 1034 to 2670 i.u. vitamin A/kg at 4, 8 and 12 weeks of age. The average weights of the birds at 4, 8 and 12 weeks of age were significantly greater when the diet was supplemented with 4721 i.u. vitamin A/kg.     

Induction of vitamin A deficiency in turkeys

The objective of this study was to determine the relationship between the hepatic vitamin A (VitA) level and the pathologic changes in the oropharynx and esophagus of VitA-deficient turkeys. Study turkeys were provided with a diet sufficient (11,000 IU/kg) or deficient (2750 IU/kg) in VitA from 4 to 17 wk of age. Body weight, bacterial culture, and tissues from internal organs were collected at weekly intervals. VitA deficiency causes epithelial tissue damage in poultry. This epithelial damage was seen grossly as white plaques in the oropharynx and esophagus and histologically as squamous metaplasia of mucosal glands and keratinization of epithelium. No significant difference in body weights was seen among the groups. Moreover, no pathogenic bacteria was isolated during sampling periods. Liver VitA levels declined significantly after consumption of low VitA diet for 3 wk and were depleted after 5 wk. Squamous metaplasia due to VitA deficiency developed in the esophagus after 3 wk and in the oropharynx after 4 wk of consuming a VitA-deficient diet.     

Staphylococcosis of turkeys. 2. Assay of protein A levels of staphylococci isolated from turkeys

Ninety-eight Staphylococcus aureus isolates and 227 coagulase-negative staphylococcal isolates from turkeys were assayed for protein A content. The amount of protein A of each isolate was quantitated using a direct enzyme-linked immunosorbent assay. Of the S. aureus isolates, 83% possessed some protein A, whereas only 13% of the coagulase-negative staphylococci contained some protein A. No correlation was seen between protein A content and ability to adhere to turkey cells. No differences in virulence were seen between isolates of S. aureus possessing high or low levels of protein A; however, an isolate with no protein A was avirulent.     

关于鹅副粘病毒病诊治的报告

养鹅一直是我国的传统,深受广大农民喜爱,80年代随着我国经济蓬勃发展,国家又大力推广发展草食动物和鼓励开发绿色食品工作,养鹅业作为一个产业发展在我国得到迅速壮大,并朝规模饲养方向发展,然而随着规模化的发展、饲养密度的增加、对生物安全的忽视以及受养殖者技术水平制约等因素的影响,我国出现了一些新的鹅的传染病,甚至是烈性传染病,能使全群覆灭,造成毁灭性的损失,鹅副粘病毒病便是其中之一.鹅副粘病毒病是97年由王永坤教授等首次在江苏发现,它以高发病率和高死亡率在我国很快流行,并严重威胁着我国的养鹅业.它的病毒属于副粘病毒Ⅰ型基因Ⅶ型,与鸡的新城疫同属,血清学显示两者有交叉性,两者是否有生物源性,仍需做进一步试验考证,就临床工作者而言,如何进行有效诊断、治疗与预防非常重要.下面我将遇到的一例鹅副粘病毒病诊治情况向大家报告一下:     

鹅源禽Ⅰ型副黏病毒的分离与鉴定

鹅副黏病毒是鹅的一种烈性传染病,该病使10日龄以内的雏鹅发病率和病死率均达到100%,平均发病率和病死率分别为27.7%和18.2%.     

A pathologic study of wild turkeys in Connecticut

During the 1984 to 1986 spring hunting seasons in Connecticut, viscera from 300 hunter-killed wild turkeys and blood samples from live-trapped wild turkeys were examined in order to establish a health profile on the State's wild turkey population. Seven species of endoparasites were recovered from 224 (75%) of 300 birds: Metroliasthes lucida, Ascaridia dissimilis, Heterakis gallinarum, Syngamus trachea, Capillaria species, Trichomonas gallinarum, and Eimeria species. The most prevalent parasites were A. dissimilis (52%) and M. lucida (37%). Although some turkeys harbored high intensities of these two helminths, there were no associated gross or microscopic lesions nor body weight changes. The prevalence of S. trachea, H. gallinarum, Capillaria and Eimeria species, which are potential pathogenic parasites in domestic and wild turkeys, was very low (less than 3%). Blood samples from 19 live-trapped wild turkeys were negative for hemoprotozoa and antibodies to 15 common bacterial and viral agents. Serum samples from 82 birds were negative for Mycoplasma gallisepticum and Mycoplasma synoviae. The survey indicates that the wild turkey population of Connecticut presently has little evidence of common infectious diseases and minimal prevalence of potentially pathogenic parasites.     

A paramyxovirus of serotype 3 isolated from African and Australian finches

Two virus isolates were obtained from exotic finches (Ortygospiza atricollis and Poephila cincta) suffering from apathy, diarrhea, conjunctivitis, and dysphagia. The isolates were identified as paramyxoviruses based on their multiplication characteristics in embryonating chicken eggs, chicken embryo fibroblasts, and chicken embryo kidney cell cultures, on morphology upon electron microscopy, and on other biological properties. Both isolates were serologically related to the reference strain of the paramyxovirus serotype 3. Intravenous infection of 42-day-old chicks resulted in no clinical signs, but intracerebral infection of 1-day-old chicks resulted in mortality and intracerebral pathogenicity indices of 0.25 to 0.35. Of five finches from various species inoculated with isolate 840/85, three remained clinically healthy through 6 weeks, but two died: one (Poephila cincta) 5 days postinoculation after showing nervous distress, and the other (Amandava amandava) suddenly 42 days postinoculation.