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1.
Distribution of lymphoid leukosis virus and p27 group-specific antigen in tissues from laying hens 总被引：1，自引：0，他引：1
In order to gain insight into transmission and pathogenesis of infection, specimens from laying hens that had been naturally exposed to lymphoid leukosis virus (LLV) were tested for group-specific antigen (gsa) of the virus by immunofluorescence (IF), complement fixation (CF), and the enzyme-linked immunosorbant assay (ELISA). Electron microscopic examinations determined the distribution of C-type virus particles in tissues, and the phenotypic-mixing test served as a biological assay for exogenous LLV. The IF gsa was found in all organs tested, and fluorescence was usually found where virus particles were concentrated. In the oviduct and intestine, IF gsa was frequently at the border of the lumina and in the connective tissue associated with basal membranes of glands. In skin, the antigen was detected in smooth muscle, in feather pulp, and in basal epidermal cells of developing feathers. Results of various tests on Ottawa strains of chickens were usually in agreement. For example, among hens that shed gsa into egg albumen, only the viremic hens were consistently positive for IF gsa in both spleens and oviducts. Geometric mean CF titers of antigen were respectively five- and 23-fold higher in spleens and oviducts from viremic hens than in those from nonviremic hens. These findings suggest that the gsa was associated with exogenous virus infection. In Cornell S strain hens that had not been exposed to LLV, gsa was detected in splenic tissue by CF and ELISA but not by the IF test. This gsa was presumed to be of endogenous origin. 相似文献
2.
Sugiyama M Koimaru H Shiba M Ono E Nagata T Ito T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(8):783-787
Decreases in egg production and increased incidence of abnormal eggs due to malformation of egg shells were observed in specific pathogen free (SPF) 173-day-old laying hens inoculated intravenously with an avian metapneumovirus (aMPV) strain PLE8T1. This strain was derived from an isolate from broiler birds exhibiting swollen head syndrome (SHS). Some SPF birds inoculated with the virus showed, slight diarrhea without any respiratory symptoms. Thus, the PLE8T1 strain was used as a challenge virus to evaluate efficacy of aMPV vaccines. SPF chickens which received a live attenuated aMPV vaccine (NEMOVAC; Merial) at 7 or 77 days old and an inactivated aMPV vaccine (OVO-4; Merial) at 105 days old were protected against poor egg production caused by the challenge with the PLE8T1 strain. Thus, aMPV, the PLE8T1 strain passaged 22 times after isolation, from birds exhibiting SHS, could induce a drop in egg production in laying hens accompanied by malformation of egg shells. It was suggested that this challenge system could be applied to evaluate the efficacy of aMPV vaccine. 相似文献
3.
Contamination of eggs by Salmonella Enteritidis has been a prominent cause of human illness for several decades and is the focus of a recently implemented national regulatory plan for egg-producing flocks in the United States. Salmonella Heidelberg has also been identified as an egg-transmitted pathogen. The deposition of Salmonella strains inside eggs is a consequence of reproductive tract colonization in infected laying hens, but prior research has not determined the relationship between the numbers of Salmonella that colonize reproductive organs and the associated frequency of egg contamination. In the present study, groups of laying hens in two trials were experimentally infected with large oral doses of strains of Salmonella Enteritidis (phage type 13a), Salmonella Heidelberg, or Salmonella Hadar. Reproductive tissues of selected hens were cultured to detect and enumerate Salmonella at 5 days postinoculation, and the interior contents of eggs laid between 6 and 25 days postinoculation were tested for contamination. Significantly more internally contaminated eggs were laid by hens infected with Salmonella Enteritidis (3.58%) than with strains of either Salmonella Heidelberg (0.47%) or Salmonella Hadar (0%). However, no significant differences were observed between Salmonella strains in either isolation frequency or the number of colony-forming units (CFU) isolated from ovaries or oviducts. Salmonella isolation frequencies ranged from 20.8% to 41.7% for ovaries and from 8.3% to 33.3% for oviducts. Mean Salmonella colonization levels ranged from 0.10 to 0.51 log CFU/g for ovaries and from 0.25 to 0.46 log CFU/g for oviducts. Although parallel rank-orders were observed for Salmonella enumeration (in both ovaries and oviducts) and egg contamination frequency, a statistically significant relationship could not be established between these two parameters of infection. 相似文献
4.
Takahiro Nii 《The Journal of Poultry Science》2022,59(2):105
The mucosa of the intestine and oviduct of hens are susceptible to pathogens. Pathogenic infections in the mucosal tissues of laying hens lead to worsened health of the host animal, decreased egg production, and bacterial contamination of eggs. Therefore, better understanding of the mechanisms underlying mucosal barrier function is needed to prevent infection by pathogens. In addition, pathogen infection in the mucosal tissue generally causes mucosal inflammation. Recently, it has been shown that inflammation in the oviduct and intestinal tissue caused by disruption of the mucosal barrier function, can affect egg production. Therefore, it is vitla to understand the relationship between mucosal barrier function and egg production to improve poultry egg production. This paper reviews the studies on (1) oviductal mucosal immune function and egg production, (2) intestinal inflammation and egg production, and (3) improvement of mucosal immune function by probiotics. The findings introduced in this review will contribute to the understanding of the mucosal barrier function of the intestine and oviduct and improve poultry egg production in laying hens. 相似文献
5.
Internal contamination of eggs laid by hens infected with Salmonella enteritidis has been a prominent international public health issue since the mid-1980s. Considerable resources have been committed to detecting and controlling S. enteritidis infections in commercial laying flocks. Recently, the Centers for Disease Control and Prevention also reported a significant association between eggs or egg-containing foods and S. heidelberg infections in humans. The present study sought to determine whether several S. heidelberg isolates obtained from egg-associated human disease outbreaks were able to colonize reproductive tissues and be deposited inside eggs laid by experimentally infected hens in a manner similar to the previously documented behavior of S. enteritidis. In two trials, groups of laying hens were orally inoculated with large doses of four S. heidelberg strains and an S. enteritidis strain that consistently caused egg contamination in previous studies. All five Salmonella strains (of both serotypes) colonized the intestinal tracts and invaded the livers, spleens, ovaries, and oviducts of inoculated hens, with no significant differences observed between the strains for any of these parameters. All four S. heidelberg strains were recovered from the interior liquid contents of eggs laid by infected hens, although at lower frequencies (between 1.1% and 4.5%) than the S. enteritidis strain (7.0%). 相似文献
6.
Rhode Island Red laying hens that lacked hemagglutination-inhibition antibody were inoculated orally with the JPA-1 strain of adenovirus isolated from a flock affected with egg-drop syndrome-1976 in Japan and observed for 80 days. Inoculated hens laid abnormal eggs, such as shell-less, soft-shelled, and cracked eggs and those with loss of pigmentation, from 8 days postinoculation (PI). Fifteen out of 16 hens laid abnormal eggs. Egg-production rte fell from 94% to 50% between 13 and 16 days PI. When the abnormal eggs were excluded, egg production was 17%; then it recoverd slowly, reaching 67% by the end of the experiment. The virus was recovered from various organs of inoculated hens from 3 to 7 days PI. Fluorescent antigens of the virus were observed in the epithelial cells and desquamated cells from the epithelium of the uterus and isthmus 10 and 14 days PI. 相似文献
7.
试验旨在了解产蛋鸡对犬瘟热病毒(canine distemper virus,CDV)抗原的免疫反应及其血清抗体和卵黄抗体的消长规律,为制备卵黄抗体提供依据。将CDV接种Vero细胞和DF1细胞进行传代并测定其病毒滴度,选取细胞病变出现早、病毒滴度高的Vero细胞毒作为接种病毒抗原免疫蛋鸡。每10 d免疫蛋鸡1次,第4次免疫后每30 d加强免疫1次。免疫前及免疫后每10 d采血分离血清,每5 d收集鸡蛋提取卵黄抗体,用琼脂扩散法和间接ELISA法测定其抗体水平。结果显示,血清抗体比卵黄抗体的滴度高,两者呈正相关性,卵黄抗体出现较血清抗体迟3~5 d,卵黄抗体在第3次免疫后3~5 d就已达到较高水平,此时即可开始收集鸡蛋制备卵黄抗体。 相似文献
8.
采用SP法检测商品蛋鸡感染J亚群禽白血病病毒对产蛋性能的影响 总被引：6，自引：0，他引：6
本研究属世界上首次报道J亚群禽白血病病毒感染对蛋鸡产蛋性能的影响。尸体剖检观察到产蛋鸡的生殖系统发育不良，表现为卵巢、输卵管幼稚型，输卵管粗细不均。组织病理学观察，发现卵巢组织中有大量的胞浆内充满球形嗜酸性颗粒的骨髓瘤细胞。用特异性抗J亚群禽白血病病毒(ALV—J)囊膜糖蛋白gp85的单克隆抗体检测不产蛋鸡的卵巢、输卵管等待检的组织切片，均检出病毒阳性抗原。结果表明ALV—J的感染造成产蛋鸡卵巢、输卵管发育不良，是蛋鸡不产蛋的直接原因。 相似文献
9.
The objective of this study was to isolate and identify suspected pathogens from peacocks and peacock farmers with severe pneumonia and to investigate its potential association with peacocks' pneumonia, caused by Chlamydophila psittaci infection. A clinical examination of infected peacocks identified birds with symptoms of anorexia, weight loss, yellowish droppings, airsacculitis, sinusitis, and conjunctivitis, whereas the infected farmers showed high fever and respiratory distress. Immunofluorescence tests detected chlamydial antigens in pharyngeal swabs (12 of 20) and lung tissue samples (four of five) from peacocks. One of four swabs taken from farmers was also positive by the same test. Specific anti-chlamydia immunoglobulin G was detected in 16 of 20 peacocks and four of four peacock farmers. The isolated pathogen was able to grow in specific-pathogen-free (SPF) chicken embryos and McCoy cell lines and was identified as Chlamydiae by immunofluorescence assay and PCR. Avian influenza virus, Newcastle disease virus, and infectious bronchitis virus were eliminated as potential causative agents after pharyngeal swabs inoculated onto the chorioallantoic membrane of embryonate eggs failed to recover viable virus. PCR and restriction fragment length polymorphism indicated the ompA gene from the isolate was similar to that of avian C. psittaci type B. Three-week-old SPF chickens challenged with the peacock isolate via intraperitoneal injection showed a typical pneumonia, airsacculitis, and splenitis. Subsequently, the inoculating strain was recovered from the lungs of challenged birds. This is the first report of C. psittaci infection in peacocks and peacock farmers. 相似文献
10.
为了解产蛋鸡对犬瘟热病毒杭原的免疫反应及其血清抗体和卵黄抗体的消长规律及相关性,为制备卵黄抗体提供依据,将犬瘟热病毒接种Vero细胞和DF1细胞进行传代并测定其病毒滴度,选取细胞病变出现早,病毒滴度高的Vero细胞毒作为接种病毒抗原免疫蛋鸡。通过每10d进行蛋鸡免疫一次,四免后每30d加强免疫一次的方法进行免疫。免疫前和免疫后每10d采血分离血清和每5d收集鸡蛋提取卵黄抗体,用琼脂扩散法和间接ELISA法测定其抗体水平。结果显示,血清抗体比卵黄抗体的滴度高,两者间呈正相关性,卵黄抗体出现较血清抗体迟3～5d,卵黄抗体在三免后3～5d就已达到较高水平,此时即可开始收集鸡蛋制备卵黄抗体。 相似文献
11.
Campylobacter jejuni frequently colonizes the avian intestine. Recent evidence suggests that this organism can also colonize the oviduct of laying hens. However, the source and role of this colonization are unknown. Isolates from the ceca, cloacae, and oviducts of 11 laying hens in three intensive egg-producing flocks were genotyped by Fla typing with the restriction fragment length polymorphism of the polymerase chain reaction product of the flaA and flaB genes (fla typing) and pulsed-field gel electrophoresis (PFGE). A diversity in fla types and PFGE types was observed within and between flocks. Individual birds could be colonized by different genotypes at various intestinal and oviduct sites. However, the oviduct of individual birds appeared to be colonized by only one genotype at the time of sampling. In two birds, matching isolates investigated from the intestinal and reproductive tracts were genotypically identical but different from those oviduct isolates found in other birds in the same flock. Interestingly, not all cecal isolates appeared to be equally able to colonize the oviduct. These results suggest that oviduct colonization may result from ascending infection via the cloaca and that some strains of C. jejuni may be better adapted than others to oviduct colonization. 相似文献
12.
Furusawa N 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2002,49(6):334-336
Laying hens were administered orally with a single dose of p,p'-(DDT) (1 mg/kg bodyweight). The concentrations (microg/g) of DDT or its metabolites, p,p'-(DDE) and p,p'-(DDD), in the main tissues involved in egg formation (blood, liver, ovary, and oviducts) and egg yolk, collected 1 day after DDT dosing, were determined by normal-phase high-performance liquid chromatography. The limits of detection were 0.04 microg/g for DDT, 0.07 microg/g for DDE and 0.06 microg/g for DDD. In extractable fats from the above tissues and egg yolk, DDT and DDE were transferred/distributed throughout the tissues and egg yolk. DDD was detected only in the liver. The findings indicate that DDT is metabolized instantaneously to DDE/ DDD in the hen's body and they are transferred rapidly into the egg-forming tissues and egg yolk. Among the four tissues and yolk fats examined, the DDT levels were high in the ovary, oviduct and egg yolk; the DDE levels were high in the liver, ovary and oviduct and lowest in the yolk (P < 0.01). 相似文献
13.
Detecting infected laying flocks is a vital part of many efforts to control egg-associated transmission of Salmonella enteritidis to humans. The relationship between the development of a specific antibody response in infected hens and the deposition of S. enteritidis in eggs is important for establishing the epidemiologic relevance of serologic testing methods. In two trials, laying hens were infected with large oral doses of phage types 13a and 14b isolates of S. enteritidis. Approximately 38% of all infected hens produced at least one contaminated egg, at an overall incidence of 5.2%, between 3 and 23 days postinoculation. As determined by enzyme-linked immunosorbent assay with an S. enteritidis flagellar antigen, 91.7% of inoculated hens produced specific serum antibodies. Although hens with very high antibody titers were associated with a significantly elevated frequency of egg contamination, a consistently direct relationship was not evident between the magnitude of the antibody responses of individual hens and the frequency at which they laid contaminated eggs. Accordingly, although serologic tests can be valuable screening tools for preliminary detection of S. enteritidis infections in poultry, the magnitude of the antibody responses detected in individual hens may not predict the overall risk of egg contamination associated with particular laying flocks. 相似文献
14.
Experimental infection models are valuable tools for understanding and preventing the deposition of Salmonella enteritidis inside eggs. Oral inoculation is believed to closely simulate naturally occurring S. enteritidis infections of chickens, but oral infection studies have often generated relatively low frequencies of egg contamination. The present study assessed whether repeated in vivo passage of an S. enteritidis strain could affect its ability to cause egg contamination in experimentally infected hens. The incidence of egg contamination was determined in groups of hens inoculated orally with either a phage type 13a S. enteritidis strain or derivatives of this parent strain that were obtained by three successive rounds of passage and reisolation from tissues of infected hens. Passaged S. enteritidis isolates recovered from ovaries and oviducts induced a significantly higher incidence of egg contamination (16.97%) than was attributed to the parent strain (8.27%). However, passaged S. enteritidis isolates recovered from livers and spleens were not associated with a significantly increased frequency of deposition in eggs. By either inducing or selecting for the expression of relevant microbial properties, passage of S. enteritidis through reproductive tissues of chickens may be useful for improving the efficiency at which experimental infection models produce egg contamination. 相似文献
15.
K Tsukamoto M Hasebe S Kakita Y Taniguchi H Hihara Y Kono 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(1):99-103
The efficacy of the albumen test for infectious avian leukosis virus (ALV) was examined in detecting congenitally transmitting hens. Seventy-three White Leghorn non-viremic hens with antibody to ALV were used. Eleven of the hens shed infectious ALV into their egg albumen, whereas only 7 of the 11 ALV-positive hens shed ALV antigens. The egg albumen test for infectious ALV was shown to be more effective in detecting the congenitally transmitting hens than that for ALV antigens. Then, twenty of the 62 hens which shed no infectious ALV into the albumen were studied for transmission of ALV to their embryos and for discharging ALV into the oviduct and vagina. Six of the 50 embryos from 4 hens were found to be infected with ALV but all of the 227 embryos from remaining 16 hens were free from the infection. Discharge of the virus into the oviduct and vagina was found both in the 4 transmitting hens and in 6 of the 16 non-transmitting hens. These results suggest that the hens discharging ALV into the oviduct, even though they do not shed ALV into egg albumen, may transmit the virus sporadically to their embryos. 相似文献
16.
A condition similar to egg-drop syndrome-1976 (EDS-76) occurred in 14 broiler breeding flocks in 2 farms in Japan from December 1978 to January 1980, and it was diagnosed as EDS-76 by serologic and virological investigations. Egg production fell suddenly when the hens were 30 to 55 weeks of age, and the depression lasted 3 to 7 weeks. Production fell 6 to 25%. Depressed egg production was accompanied by the laying of shell-less, soft-shelled, and thin-shelled eggs associated with loss of egg-shell pigment. Eleven isolates of hemagglutinating adenovirus were isolated from cloacal swabs (10 isolates) and a uterus (1 isolate) of hens in one farm. One isolate, cloned and named JPA-1, had the same antigenicity in serologic tests and the same biological and physicochemical properties as the BC14 strain of EDS-76 virus. 相似文献
17.
In order to develop better control measures against avian influenza, it is necessary to understand how the virus transmits in poultry. In a previous study in which the infectivity and transmissibility of the pandemic H1N1 influenza virus was examined in different poultry species, we found that no or minimal infection occurred in chicken and turkeys intranasally (IN) inoculated with the virus. However, we demonstrated that the virus can infect laying turkey hens by the intracloacal (IC) and intraoviduct (IO) routes, possibly explaining the drops in egg production observed in turkey breeder farms affected by the virus. Such novel routes of exposure have not been previously examined in chickens and could also explain outbreaks of low pathogenicity avian influenza (LPAI) that cause a decrease in egg production in chicken layers and breeders. In the present study, 46-wk-old specific-pathogen-free chicken layers were infected by the IN, IC, or IO routes with one of two LPAI viruses: a poultry origin virus, A/chicken/CA/1255/02 (H6N2), and a live bird market isolate, A/chicken/NJ/12220/97 (H9N2). Only hens IN inoculated with the H6N2 virus presented mild clinical signs consisting of depression and anorexia. However, a decrease in number of eggs laid was observed in all virus-inoculated groups when compared to control hens. Evidence of infection was found in all chickens inoculated with the H6N2 virus by any of the three routes and the virus transmitted to contact hens. On the other hand, only one or two hens from each of the groups inoculated with the H9N2 virus shed detectable levels of virus, or seroconverted and did not transmit the virus to contacts, regardless of the route of inoculation. In conclusion, LPAI viruses can also infect chickens through other routes besides the IN route, which is considered the natural route of exposure. However, as seen with the H9N2 virus, the infectivity of the virus did not increase when given by these alternate routes. 相似文献
18.
试验旨在研究益生菌-中草药复方制剂对蛋鸡输卵管组织、生产性能及蛋品质的影响。选取体质优良的45周龄的海兰褐蛋鸡720只,随机分成4组,每组3个重复,每个重复60只。对照组饲喂不含抗生素的基础日粮,Ⅰ、Ⅱ和Ⅲ组为试验组,分别在基础日粮中添加1.0‰中草药组方一(败酱草、蒲公英、板蓝根、连翘等)、1.0‰中草药组方二(金银花、黄芪、淫羊藿、益母草等)和1.0‰中草药组方三(大青叶、黄柏、黄芩、栀子等),且各试验组均添加1.5‰复合益生菌。预试期7 d,正试期28 d。结果表明:①益生菌-中草药复方制剂能修复蛋鸡受损的输卵管组织,减少输卵管与周围组织的黏连,使输卵管保持通畅性,降低蛋鸡输卵管组织中肿瘤坏死因子-α(TNF-α)和表皮生长因子受体(EGFR)含量,尤以Ⅱ组效果最好,分别较对照组降低40.85%和17.79%,差异显著(P<0.05);②与对照组相比,Ⅱ组可显著提高蛋鸡产蛋率(P<0.05),显著降低料蛋比和软破蛋率(P<0.05);③与对照组相比,Ⅱ组可显著提高48和50周龄蛋鸡的蛋形指数和蛋黄比率(P<0.05)。由此可知,日粮中添加益生菌-中草药复方制剂能在一定程度上减轻蛋鸡输卵管炎症反应,提高产蛋率,改善蛋品质,其中以Ⅱ组益生菌和金银花、黄芪、淫羊藿、益母草等中草药联合使用效果最好。 相似文献
19.
In Experiment 1, mature laying hens were inoculated intravaginally with 10(6) colony-forming units of Salmonella enterica serovar enteritidis (S. enteritidis), Salmonella typhimurium, Salmonella infantis, Salmonella hadar, Salmonella heidelberg, or Salmonella montevideo to compare their abilities to colonize the reproductive organs of chickens and to contaminate eggs. Salmonella enteritidis was more frequently recovered (from 11 of 40 eggs, 27.5%) than the other serovars, and especially the inner shell was contaminated with these organisms in 10 of 40 eggs (25.0%). The contamination rates and the viable counts in cloaca were significantly (P < 0.05) higher in hens inoculated with S. enteritidis than in those inoculated with the other serovars at 4 days postinoculation (PI). In the vagina, the positive rates were 90%-100% in hens inoculated with S. enteritidis, and the viable counts of the organisms in this portion were significantly (P < 0.05) higher than those of the other serovars at 2, 4, and 7 days PI. The ceca were colonized similarly by each serovar at 7 days PI. The spleen and ovary were infected with S. enteritidis in three and one hen, respectively. No Salmonella was recovered from liver and peripheral blood in any hen. Salmonella enteritidis was recovered from other oviductal portions than the vagina (10%-20%), whereas no forming egg was contaminated in the oviduct. In Experiment 2, the in vitro adherence of these six serovars to the vaginal epithelium was compared with vaginal explants. The mean number of S. enteritidis attaching to the secondary villi in the vaginal lumen was significantly (P < 0.05) higher than those of the other serovars. These results suggest that S. enteritidis has a specific advantage over the other Salmonella serovars by its capacity to colonize the vaginal tissues of hens, and this higher affinity of S. enteritidis to the vagina may play a significant role in the production of many S. enteritidis-contaminated eggs. 相似文献
20.
本试验选用正在产蛋和休产的来航鸡,用放射配体结合分析法,分别测定两组鸡的肝脏和输卵管胞浆和胞核受体含量。胞浆液的蛋白含量用考马斯亮蓝G250法测定;胞核DNA含量用紫外吸收法测定。试验结果表明:两组鸡的肝脏和输卵管的胞浆雌激素受体含量均无明显差异;两组鸡的肝脏和输卵管的胞核雌激素受体含量,产蛋鸡肝脏的胞核雌激素受体是休产鸡的15倍,差异显著(P<0.05),而输卵管的胞核雌激素受体差异不明显。 相似文献