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1.
In a feeding trial lasting for months Halothane-positive fattening pigs were put on a diet containing different concentrations of vitamin E and selenium. After a Myostress application vitamin E and selenium were additionally injected in order to examine stress resistance (CK-test) and regenerative capacity (histological examination of Musculus longissimus dorsi) of skeletal muscle. The study revealed that neither high dietary levels of vitamin E/selenium nor a vitamin E/selenium treatment applied after stress are capable of preventing stress related myopathy nor can they influence its healing up favourably.  相似文献   
2.
Epidermal growth factor (EGF)-like activity was measured in mares' colostrum and milk by radioreceptor assay. Milk samples were collected from 22 mares 1 or more times during early lactation. Samples of colostrum were taken after parturition and before the foal first suckled (presuckle), within 6 hours after the foal first suckled (postsuckle), and on days 1, 2, 4, and 8 of lactation. In the 5 mares from which milk samples were obtained at each sampling time, presuckle colostral mean EGF-like activity (17.8 ng/ml) was greatest (P less than 0.05). The mean values for EGF-like activity at all other sampling times were not significantly different from each other (postsuckle colostrum, 9.7 ng/ml; day 1, 9.6 ng/ml; day 2, 8.5 ng/ml; day 4, 8.0 ng/ml; day 8, 7.8 ng/ml).  相似文献   
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Seven of 30 canaries in an aviary in New Zealand developed ophthalmic problems. Clinically, 5 birds had unilateral and 2 birds had bilateral lesions characterized by conjunctivitis, crusty exudates on eyelids, and collapse of the eyeball. Microscopic lesions in 12 of 14 eyes examined included inflammation of the choroid and retina, with osseous replacement of the globe in some. Numerous Toxoplasma gondii tachyzoites were seen in the detached retina and vitreous humor of acutely affected birds. The diagnosis of toxoplasmosis was confirmed by immunohistochemical staining with T gondii antiserum. Affected birds had encephalitis, and T gondii was localized in the brains of these by immunohistochemical examination and by use of bioassays in mice. Toxoplasmosis should be considered in differential diagnosis of ophthalmitis in canaries.  相似文献   
5.
M R Rekik  A Silim 《Avian diseases》1992,36(2):237-246
Total RNA of eight avian reovirus isolates and the S1133 strain were compared by RNase T1-oligonucleotide mapping. The viruses were propagated in Vero cell cultures, and viral genomes were extracted from purified virions for comparison. Pairwise comparisons of the oligonucleotide maps showed genetic variation among reovirus isolates ranging from 78% to 99%. The T1 fingerprints of the RNA of isolates 1103, 724, 615, and 684 differed slightly from the standard S1133 strain, suggesting that the vaccine strain might have changed and became part of the circulating reoviruses. In contrast, when compared with the vaccine strain, isolates 902, 644, and 6207 showed greater differences in the fingerprint pattern. This genomic diversity may be due to the differences in immunological status of the affected avian population and/or due to simultaneous coinfection with different reovirus strains.  相似文献   
6.
聚丙烯酰胺凝胶电泳法鉴定禽呼肠孤病毒   总被引:1,自引:0,他引:1  
从感染禽呼肠孤病毒的细胞中,以SDS和酚提取病毒核酸,通过聚丙烯酰胺凝胶电泳(PAGE)法将分节段的核酸分开,经银染色显示,呈3-3-1-3分布,此法可用于禽呼肠孤病毒的快速检测、鉴定。同样方法未能使传染性法氏囊病毒核酸显示。  相似文献   
7.
The proximal straight tubules of the female mouse kidney exhibit heavy periodic acid Schiff (PAS) staining in their brush borders and numerous cytoplasmic granules. In the present study, the female DBA/2Cr mouse kidney was examined, using various fixatives (formalin, PFA, PLP, Zamboni's, Bouin, or Carnoy solution) and various staining methods (HE, PAS, alcian blue, periodic acid methenamine-silver (PAM), toluidine blue, azan, or Congo red). Under azan and PAM, the staining pattern of the brush border was similar to that of PAS, and few effects of the fixative were observed. Cytoplasmic granules were clearly detected with PAM as well as PAS. However, these granules were not detected with Carnoy solution. Furthermore, distribution of granules differed between PAS and PAM.  相似文献   
8.
The crossreactivity of mouse monoclonal antibodies (MoAbs) (Tab. I) prepared against human HLA-DR and HLA-DP antigens was studied in various bovine cells: lymphocytes from lymph nodes and peripheral blood, adherent (B) and nonadherent (T) lymphocytes, monocytes, granulocytes and platelets. In the immunofluorescence test, MoAbs Bra13, Bra14, Bra20, Bra22, Bra30, Bra70, HL-38 reacted with bovine B lymphocytes and monocytes, but not with other tested cells (Tab. III, IV). These antibodies, except Bra22, were positive with B lymphocytes in the complement dependent cytotoxic test (Tab. II). The similarity of the bovine antigens and HLA-DR antigens determined by used MoAbs was also proved by immunoblotting. Monoclonal antibodies Bra38 and BraFB6 did not react with the bovine cells and separated antigens. The epitope (HLA-DR) recognized by the antibody Bra38 is probably absent in cattle. The presence of HLA-DP analogue determined by the antibody BraFB6 has not been confirmed. The crossreactive MoAbs could be used for the detection of B lymphocytes and macrophages in veterinary immunology.  相似文献   
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A disease causing the decline of papaya (Carica papaya) plants was noticed in the Jordan Valley in 1982. The disease caused severe yellowing of the upper leaves and dieback of the apex. The disease was not transmissible mechanically and continued efforts to associate viruses and viroids have so far been unsuccessful. Epidemiological observations suggested that the disease is airborne and probably caused by a mollicute. In order to test this hypothesis, plots were covered by an insect-proof net and with white nets providing 15, 30 and 50% shade. The 30%, 50% and insect-proof nettings provided complete protection, and the 15% netting reduced disease incidence to <2%, compared with>37% in the uncovered control plot. Spraying plants at weekly intervals with a commercial whitewash solution was also found to be effective in reducing disease incidence. The advantages of using a range of netting field treatments as a simple means for obtaining information on the epidemiological nature of a new disease are described.  相似文献   
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