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The dynamics of the serum concentration of protein 27 (P27) of avian leukosis virus and transforming growth factor 2 (TGF-2) were compared during the period between 29 and 59 weeks of age in two flocks of broiler chicken breeding stock undergoing outbreaks of severe lymphoid leukosis (LL) associated with persistent high mortality (susceptible) and in another two flocks of breeding stock with the presence of avian leukosis virus in association with low mortality due to LL (resistant). The average mean concentration of serum P27 in the LL-susceptible flocks was significantly higher (<0.05) than that in the LL-resistant flocks in six out of seven samplings performed at 5-week intervals, between 29 and 59 weeks of age. The peak in the average rise of serum P27 in the LL-resistant flocks (309 pg/ml) was associated with the highest level of TGF-2 (1282 pg/ml) among all flocks and at all sampling times. The significance of TGF-2 in inhibition of lymphoid tumour development is discussed.  相似文献   
2.
The purpose of this study is to attempt the induction of early immunopotentiation of antibodies specific to fimbriae of Salmonella enterica serovar Enteritidis (SE), by administering thymulin and zinc to SE-vaccinated chicken breeders, and the improvement of protection against a controlled-live challenge by SE. The first two groups of breeders were administered subcutaneously at 15 and 19 weeks of age a killed SE vaccine. Breeders of the third and fourth groups were left unvaccinated. Breeders of the first group, immunopotentiated by thymulin and zinc, were able to induce the earliest antibodies in their pooled sera at 2 weeks post the first SE-vaccination, specific to fimbriae (approximately 21 KDa) of SE. However, the second group that was only vaccinated with the same SE-vaccine produced specific antibodies to fimbriae at 3 weeks following the second vaccination (22 weeks of age). Breeders of the third group, that were neither SE-vaccinated nor immunopotentiated by thymulin and zinc, but were challenged by live SE at 22 weeks of age, were able to show specific antibodies to fimbriae at 3 weeks post challenge (25 weeks of age). The fourth group that was deprived of SE-vaccination, immunopotentiators, and challenge didn't show any background antibodies specific to SE-fimbriae. The presence of the earliest antibody-immunopotentiation to fimbriae of SE in breeders of the first group, administered thymulin and zinc, was associated with the lowest frequency of SE-infected ceca (10%) among the challenged groups. In addition, breeders of the first group were the only challenged birds resulting in absence of SE infection in their cecal tonsils. The first group-vaccinated, immunopotentiated, and challenged, and the second group-vaccinated and challenged only resulted in breeders with absence of SE infection in their oviducts and spleens. In conclusion, immunopotentiation of chicken breeders by thymulin and zinc induces the earliest specific antibodies to fimbriae of SE associated with the lowest frequency of SE-infected ceca, and absence of SE infection from cecal tonsils, oviducts and spleens.  相似文献   
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4.
A 2.5-year-old female Thoroughbred was examined because of lethargy, anorexia, and weight loss. Analysis of a CBC revealed erythrocytosis and an increase in PCV. Serum biochemical analysis revealed increases in activities of several hepatic enzymes. Ultrasonography revealed hepatomegaly and a heterogeneous appearance of the hepatic parenchyma. The horse did not improve despite supportive care, and it was euthanatized. Necropsy revealed numerous raised white to gray foci in the liver. Histologically, these foci consisted of neoplastic cells that resembled fetal hepatocytes, embryonal-type cells, and cells with features intermediate between those 2 cell types. Immunohistochemical staining revealed that hepatocytes stained strongly with anti-alpha-fetoprotein. On the basis of these results, hepatoblastoma was diagnosed. Diagnosis of hepatoblastoma is difficult, because it can appear histologically similar to other hepatic tumors, such as hepatocellular carcinomas. Definitive diagnosis requires histologic evaluation of tumor architecture and cell morphology. Immunohistochemical staining for alpha-fetoprotein in tumor cells may serve as a tumor marker but is not pathognomonic of hepatoblastoma. Paraneoplastic syndromes, such as erythrocytosis, can accompany hepatoblastoma. The prognosis for horses with hepatoblastoma is grave.  相似文献   
5.
A 6-month-old, castrated male domestic cat with progressive neurological signs of 2-3 weeks duration was necropsied. Macroscopic findings were restricted to the brain and included irregularly shaped, well-delineated but unencapsulated areas of intense black pigmentation involving the rostral portion of both cerebral hemispheres. Microscopically, numerous brown, oblong, segmented branching hyphae and conidial-like structures and extensive pyogranulomatous inflammation were identified throughout the cerebral lesion and in adjacent blood vessels. Hyphae and oval conidia were best demonstrated with either Gomori methenamine silver or periodic acid-Schiff stain. Fungal infection in the brain of this cat was unrelated to any concurrent immunodeficiency syndrome or immunosuppressive treatment. This report deals with a case of cerebral phaeohyphomycosis from which a different species of dematiaceous fungus, Cladophialophora bantiana, was isolated and identified.  相似文献   
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7.
The immunology and histopathology and the distribution of viral antigen in infections with chicken infectious anaemia virus (CIAV) and inclusion body hepatitis virus (IBHV) were compared in the broiler offspring of CIAV-vaccinated meat chicken breeders versus those in the offspring of breeders naturally exposed to field CIAV. No significant difference in the humoral antibody level specific for CIAV was observed between 5 and 33 weeks of age in the two breeder groups (p>0.05). The maternal humoral immunity to CIAV in the day-old offspring of the groups did not differ significantly (p>0.05). The humoral immunity to CIAV at 40 days of age indicated an absence of clinical signs of CIAV in the broiler offspring of both groups of breeders and this was associated with mean serum thymulin levels in offspring of both groups not differing significantly at 1 or 40 days of age. Histopathological and immunofluorescence observations did not differ significantly in the offspring of either group by CIAV or IBHV.  相似文献   
8.
The antigenic polypeptides in Salmonella Enteritidis (SE) were chronologically recognized by the chicken immune system, using Western immunoblotting. Broiler chicks challenged at three days of age with SE strain carrying the most prevalent plasmid profile of 14.1 and about (approximately) 50 kb were bled at 17, 24, 31, 38 and 45 days of age. Pooled sera of blood collected at each age was reacted by Western immunoblotting with banded polypeptides of three predominant SE strains that acquired the following respective plasmid profiles: 14.1 kb; 14.1 and approximately 50.0 kb; and 1.8, 14.1 and approximately 50.0 kb. The immunoblots of each pooled sera collected at a specific age against the three SE strains were similar. More specifically, the early immune response at 17 days of age had antibodies recognizing only one polypeptide in the three SE strains namely, the 35.8 kDa. At 24 or 31 days of age, the acquired immunity to infection had antibodies recognizing five similar polypeptides in the three SE strains namely, the 14.4 (fimbriae protein), 21.5 (fimbriae protein), 30.5, 35.8, and 66.2 kDa. At 38 and 45 days of age, the antibodies recognized additional polypeptides namely, the 41.5 and 55.6 kDa, respectively. The recognition of the 41.5 and 55.6 kDa polypeptides at 45 days of age was associated with higher invasiveness of SE to spleens and livers (15.6%) and in higher cecal colonization (59.4%) in comparison to absence of recognition to the two polypeptides at 31 days of age associated with low infectivity to spleens (0%), livers (3.1%), and ceca (9.4%).  相似文献   
9.
The humoral immunity, spleen and thymus weight indices, lymphocyte count in the thymus cortex, and granuloma diameter at vaccination sites were assessed in four differently immunopotentiated groups of meat chicken breeders. Breeders in the first two groups were given a killed Salmonella enterica serotype Enteritidis (SE) vaccine subcutaneously at 15 and 19 weeks of age. Breeders in the third and fourth groups were left unvaccinated. Breeders in the first group were further immunopotentiated with zinc and thymulin. Each bird in the first group was given the immunopotentiators intraperitoneally in a volume of 0.1 ml at intervals of 3 days for a period of 3 weeks, starting at 15 weeks of age. At each time, each bird in the first group received thymulin (10 ng) and ZnCl2 (1 mol/L), using a carboxymethyl cellulose carrier, totalling 90 ng thymulin and 9 mol of ZnCl2 per bird. Each bird in the first three groups was challenged orally with 6.7×106 cfu/ml of highly virulent SE organisms, at an age of 22 weeks. The first group, which had received zinc and thymulin, had the earliest and highest humoral immune response to SE (p<0.05). This was observed at 2 and 4 weeks after the first vaccination. In addition, the first group had the highest mean thymus weight index, and the highest mean lymphocyte count in the thymus cortex. No significant difference was observed between the first two vaccinated groups in the mean granuloma diameter developed at the two vaccination sites 48 h after administration of the vaccine (p>0.05).  相似文献   
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