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71.
To test the hypothesis that development of a BTV-specific IgE response plays a role in clinical disease manifestation, the humoral immune response of cattle to inactivated and virulent BTV was studied. Three calves received three sensitizing immunizations of inactivated BTV, 3 weeks apart. The BTV-sensitized animals, two non-sensitized BTV-seropositive and 4 BTV-seronegative control cattle. were challenge-exposed with BTV-11, UC8 strain. All cattle inoculated with inactivated BTV developed group-specific non-neutralizing and serotype-specific neutralizing antibodies. The development of post-challenge-exposure neutralizing antibody titers was inversely correlated with protective immunity. None of the BTV-challenged animals showed clinical disease. The levels of IgE were greatest in the sensitized calves after virus challenge in comparison with control groups. The sequential development, specificity and intensity of virus protein-specific humoral responses were evaluated using immunostaining. After challenge exposure of BTV-sensitized and non-sensitized cattle, total and IgE antibodies reacted consistently within BTV structural proteins VP2, VP5 and VP7. Although no correlation was found between clinical disease and IgE, results add support to the hypothesis that IgE may be involved in the pathogenesis of clinical disease, since infection with BTV causes an increase in serum IgE levels. However, these results suggest that the levels of virus-specific reactivity may be an important factor in determining whether or not clinical disease manifestation occurs.  相似文献   
72.
The ruminal stability of Mepron M 85 and the effect of supplementation with Mepron M 85 on free methionine level of blood were studied in rumen-fistulated cows and rumen- and duodenum-fistulated growing bulls. In five rumen-fistulated cows in situ 69.5% and 64.6% of the methionine content of Mepron M 85 was found after ruminal incubation of 16 h and 24 h, respectively. Daily rations of the rumen-fistulated cows were supplemented with 15.0 g DL-methionine and 17.7 g Mepron M 85, which increased the free methionine level of blood from 13.64 mumol/L to 15.35 and 20.46 mumol/L, respectively, three hours after feeding. In the four rumen- and duodenum-fistulated growing bulls, supplementation with 15.0 g DL-methionine and 17.7 g Mepron M 85 increased the total methionine getting into the duodenum during 24 h from 14.99 g to 16.84 and 20.84 g, respectively. The influence of Mepron M 85 on milk production was studied in 35 pairs of Hungarian Fleckvieh x Holstein-Friesian cows. The animals were coupled on the basis of the number of finished lactations, milk production in the previous lactation, and the date of calving. Daily supplementation of 18.0 g Mepron M 85 increased daily milk production significantly (p < 0.05), by 1.24 litres. Milk fat content also increased significantly (from 3.10% to 3.19%, p < 0.05) in the experimental group. The supplementation did not influence milk protein content.  相似文献   
73.
The regulation of estrogen and progesterone receptor (ER, PR) expression by estradiol (E2) and progesterone (P4) in the oviduct, uterus and cervix of female lambs was studied. The animals received three intramuscular injections of E2, P4 or vehicle with an interval of 24 h and they were slaugthered 24 h after the third injection. Determinations of ER and PR were performed by binding assays and mRNAs of ER alpha and PR by solution hybridization. High levels of ER and PR in both cervix and oviduct were found in the female lamb, differing from other mammalian species. No significant effects by either E2 or P4 treatment on ER and PR levels in the cervix and oviduct could be observed. E2 treatment increased the mRNA levels of ERa and PR more than 3-fold in the cervix, while P4 treatment increased the mRNA levels of ERa and PR in the uterus. The results show differential effects of gonadal steroids on sex steroid receptor expression along the reproductive tract in female lambs, suggesting that steroid target tissues can modulate responses to the same circulating levels of steroid hormones.  相似文献   
74.
Thirty-five Pasteurella haemolytica strains were isolated in Hungary from goat carcasses sent for postmortem examination from two farms with large goat flocks. All strains belonged to biotype A and with the exception of one strain of serotype A8 they belonged to serotype A2. No untypable strains were found by the indirect haemagglutination test.  相似文献   
75.
The authors examined 585 samples from 92 mares of 2 studs and 346 nasal swabs taken from their foals for the presence of mycoplasmas. The positive rates of mares and foals were 81.5% and 71.7%, respectively, with positivity of samples being variable. Clinical symptoms developed in 2-4 waves and lasted 3-7 days, with intervals of 7-12 days. The disease started in April among foals born in February, at an average age of 88 days. Later on, the average age of the affected foals decreased. There was a correlation between presence of mycoplasmas in nasal cavity and disease of foals.  相似文献   
76.
77.
Two Hungarian virus isolates from sweet pepper (K8) and melon (S4) were identified as cucumber mosaic virus (CMV) on the basis of host plant reactions and serology. The isolates were purified and antisera prepared. Homologous antiserum titers in double-diffusion tests were 256 (K8) and 512 (S4). They were serologically closely related to each other and to other CMV isolates. On the basis of symptoms they belong to different symptomatological groups of CMV; this was supported by serological properties. Sedimentation coefficients were c. 93 S, at 2 mg ml–1. Purified preparations, stained with 2% uranyl acetate, showed spherical particles. In ELISA purified preparations reacted with each other's antisera.Samenvatting Twee hongaarse virusisolaten uit paprika (K8) en meloen (S4) werden geïdentificeerd als komkommermozaïekvirus (CMV) met behulp van toetsplanten en serologie. Beide isolaten werden gezuiverd en er werden antisera tegen bereid. De homologe titers van de antisera in de agar-geldiffusietoets bedroegen 256 (K8) en 512 (S4). K8 en S4 waren serologisch nauw verwant aan elkaar, evenals aan andere CMV-isolaten. Op grond van hun symptomen op toetsplanten behoren ze tot verschillende symptomatologische groepen van CMV. Dit laatste werd gesteund door de serologische eigenschappen. Beide isolaten hebben een sedimentatiecoëfficiënt van ca 93 S, bij een concentratie van 2 mg ml–1. Gezuiverde preparaten, gekleurd met 2% uranylacetaat, bleken bolvormige deeltjes te bevatten. In ELISA reageerden gezuiverde preparaten van K8 en S4 met elkaars antisera.  相似文献   
78.
79.
A serological study of intermediate hosts (cattle, sheep, goats and swine) of Echinococcus granulosus was carried out by means of the indirect haemaglutination (IHA) and flocculation with latex (LA) tests, relating them with the organs invaded, and the fertility and viability of the cysts.In cattle a sensitivity of 75% and 21.05% of non-specific reactions was given by IHA, while the LA gave 66.7 and 17.54%, respectively. In the sheep, the IHA gave 79.16 and 20%, and the LA, 75 and 15%. In the goat, the IHA gave 76 and 22%, and the LA 71.43 and 16%. Finally, in the pig, the IHA gave 75 and 22%, and the LA, 66.6 and 14.16%.The IHA was more sensitive in detecting hepatic cysts in the cow, and pulmonary cysts in the goat, while in the sheep and the pig there were no significant differences. The LA was more sensitive in detecting hepatic cysts in the cow, goat and pig, while there were no significant differences in sheep.The differences in serum titers by the IHA and the LA tests with respect to the viability and the fertility of the cysts in the hosts, were not significant.  相似文献   
80.
Canine leishmaniasis is an endemic disease in the Mediterranean area caused by the protozoan Leishmania infantum, which usually produces renal failure. Sodium dodecyl sulphate polyacrylamide gel electrophoresis and Western blot using antibodies to IgG and IgA from dogs were carried out in the urine of 22 dogs with leishmaniasis diagnosed by ELISA and confirmed by PCR, and 20 healthy dogs. The results were compared to renal function laboratory tests and to those from a histopathological study of the kidneys from sick animals that died naturally or were euthanized. Five different bands with molecular weights ranging from 10 to 110 kDa were obtained from the electrophoresis of the urine of healthy dogs. 33.5% of total proteins corresponded to low molecular weight proteins and the other proteins had middle and high molecular weights. However, in the group with leishmaniasis, a maximum of 11 different bands with molecular weights ranging from 10 kDa to 150 kDa were displayed in the electrophoresis of the urine. The urine electrophoretic pattern in the sick dogs was classified as mixed (proteins with high and low molecular weights) because low molecular weight proteins made up 57.9% and the rest of the proteins had middle and high molecular weights. In Western blot, none of the healthy dogs showed excretion of IgG and/or IgA, whereas IgG and IgA were detected in the Western blot of urine of 68% and 55% respectively of dogs with leishmaniasis. The results obtained in the leishmaniasis group agreed with glomerular and tubular damage, which were confirmed by the histopathological findings.  相似文献   
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