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21.
Monoclonal antibodies against hog cholera and bovine viral diarrhoea viruses were assayed on organ tissue sections of experimentally infected animals. The animals had been infected simultaneously with both viruses. The antibodies were tested using an indirect immunofluorescence test and an indirect enzyme immunoassay with a biotin/streptavidin/peroxidase detection system. A polyclonal hyperimmune serum was used as a control in direct immunofluorescence tests. Both techniques based on monoclonal antibodies were more sensitive and more specific than the conventional test, the enzyme immunoassay being more sensitive than the immunofluorescence test. Small amounts of BVD viral antigen were demonstrable with monoclonal antibodies in most organ tissues.  相似文献   
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The state of mucus synthesis in the goblet cells of the small intestine was studied in conventional piglets infected with a dose of 200,000 oocytes of the coccidium Isospora suis the first and fifth day after parturition. The synthesis of mucus and its chemical characteristics undergo significant changes during the third and fourth day after infection. The activity of acid and neutral mucous substances declines; their level and the physiological synthetic function of goblet cells begin to return to the normal during the period starting on the eight to tenth day after infection. However, there were no fully functioning goblet cells in the broken numerical ratio even at the end of the period of investigation, i.e. the 13th day after infection. The thin surface layer of mucus remained almost unchanged within the whole extent of the small intestine parts studied.  相似文献   
24.
The utilization of dietary lysine for protein synthesis is affected by the digestibility of protein-bound lysine, by its intestinal resorption and by its oxidative catabolism. The approach chosen in this paper enables a comparison of the cumulative effect of these processes on the utilization of free and protein-bound lysine, respectively. The principle of the approach is based on a quantification of the expiration of 14C-labelled carbon dioxide after an oral administration of a diet, which contains L-(U-14C)-lysine either as a free amino acid or bound to yeast proteins. During an adaptation phase cockerels of the Japanese quail received a diet based mainly on ground wheat and wheat gluten. This diet was supplemented either with yeast proteins or with a mixture of L-amino acids which simulates the composition of the yeast proteins. In the main experiment the expiration of labelled carbon dioxide was measured during 240 minutes after the administration of the corresponding labelled diets. Just before treatment the animals were either in the postprandial phase or in a state of slight hunger. The maximum of expiration of labelled carbon dioxide occurred around the 60th minute after administration of the corresponding labelled diets. The cumulative expiration of labelled carbon dioxide, expressed in per cent of the radioactive dose used, amounts to 15.5% and 14.3% for free and protein-bound lysine, respectively. The utilization of both forms of lysine in the Japanese quail is lower than in broilers.  相似文献   
25.
A genomic library of Babesia bovis DNA from the Mexican strain M was constructed in plasmid pUN121 and cloned in Escherichia coli. Several recombinants which hybridized strongly to radioactively labeled B. bovis genomic DNA in an in situ screening were selected and further analyzed for those which specifically hybridized to B. bovis DNA. It was found that pMU-B1 had the highest sensitivity, detecting 25 pg of purified B. bovis DNA, and 300 parasites in 10 microliters of whole infected blood, or 0.00025% parasitemia. pMU-B1 contained a 6.0 kb B. bovis DNA insert which did not cross-hybridize to Babesia bigemina, Trypanosoma evansi, Plasmodium falciparum, Anaplasma marginale, Boophilus microplus and cow DNA. In the Southern blot analysis of genomic DNA, pMU-B1 could differentiate between two B. bovis geographic isolates, Mexican strain M and Thai isolate TS4. Thus, the pMU-B1 probe will be useful in the diagnosis of Babesia infection in cattle and ticks, and in the differentiation of B. bovis strains.  相似文献   
26.
A postparturient period is characterized by low basal secretion of adenohypophysis gonadotropins with the following appropriate changes in ovarian hormones and their response to the morphology of vaginal epithelium. In this study the dynamics of the cytological picture of vaginal swabs and ovarian hormones 17 beta-oestradiol (E2) and progesterone was investigated in the puerpery of ewes. The objective was to obtain and extend the knowledge of cytological changes in vaginal epithelium and levels of ovarian hormones of ewes after parturition and of their relationships from the first several days after lambing until the 51st day of the period of observation. Vaginal swabs for vaginal cytology were taken from nine ewes on days 1, 4, 7, 14, 17, 21, 25, 34, 42 and 51 after parturition. These swabs were fixed in ether-alcohol 1:1, stained according to the Faltínová-Zidovsky method, embedded in Canada balsam and evaluated by differentiation of cells according to Luksh (1953). Blood samples for E2 and P4 determinations were taken from the jugular vein in the same intervals as vaginal swabs. The serum was centrifuged and stored at -18 degrees C until use. E2 and P4 concentrations were determined radioimmunologically, using kits RIA-test ESTRA and RIA-test PROG from URVJT Kosice. A statistically significant decline (P < 0.05) of percentual representation of basal and parabasal cells (Fig. 1, Tab. I) on day 7 after lambing was replaced by their multiplication from day 14 reaching the values of 66.07 +/- 3.95 on day 42. A statistically significant decrease in intermediary flat cells (Fig. 2, Tab. II) was observed on days 14 (P < 0.001), 34 and 42 (P < 0.01; P < 0.001), in comparison with the first day after lambing. An evaluation of intermediary convoluted cells revealed their highest percentage on days 1 and 17 after parturition (34.65 +/- 4.77-20.62 +/- 12.57) and their decline to values in the range of 6.77 +/- 1.46-7.66 +/- 2.25 on the remaining days of the period of observation. Percent occurrence of superficial flat cells (Fig. 3, Tab. I) ranged from 3.9 +/- 1.10 to 10.63 +/- 7.23 from day 1 to day 51 after lambing. The lowest percentual representation (1.32 +/- 0.79-4.10 +/- 1.89) was recorded for superficial convoluted cells. Multiplication of the evaluated cells was observed, reaching the highest but insignificant representation (P > 0.05) on day 25 of postparturient investigation: 4.10 +/- 1.89 (Fig. 3, Tab. I). 17 beta-oestradiol (E2) concentrations were compared to the -1st day before parturition, when its values varied at the level of 2.45 +/- 0.64 nmol/l serum.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
27.
Application of new procedures in the sphere of the control of sexual functions requires an extension of present knowledge of postparturient endocrinium or endogenic factors comprised in postparturient physiology of sexual activity. According to recent data, oxytocin, besides its uterotonic and luteolytic activity, acts as an ovarian factor in the local intrafollicular regulation of stereidogenesis and as a modulator of uterine secretion of prostaglandines. Based on present knowledge of oxytocin effects, this study was aimed at investigation of the influence of repeated carbetocin (Depotocin inj. Spofa) administration on the dynamics of changes in thyroxine (T4), triiodothyronine (T3), 17 beta-estradiol (E2), progesterone (P4) concentrations and their mutual correlations from the 36th hour till the 51st day after parturition. Simultaneous study of a possible delayed influence of applied carbetocin on conception of ewes after oestrus evocation on day 51 after lambing was carried out. Nineteen ewes of the Slovak Merino breed, lambed in the first decade of February, were assigned to the experimental (n = 9) and to the control group (n = 10). Experimental ewes were subjected to repeated postparturient carbetocin treatment at the dose 0.07 mg per animal. The first dose was applied i. m. in 24 hours, and the second in 72 hours after parturition. On day 51 oestrus was induced in nine ewes of each group by combined treatment with chlorsuperlutin (Agelin, vaginal pessaries, Spofa) and PMSG (500 I.U./animal). On the day of PMSG application ewes were housed together with rams for the period of the next six days. Samples of blood were taken 24 hours before parturition (-1st day), up to 36 h after parturition and on days 4, 7, 14, 17, 21, 25, 34, 42 and 51 after parturition. Concentrations of T4, T3, E2 and P4 were determined by commercial kits RIA-test-T4; RIA-test-T3; RIA-test-ESTRA and RIA-test-PROG (URVJT Kosice). Animal of the control group showed variations of T4 concentrations (Tab. I, Fig. 1) at the level of original values (59.4 +/- 9.69 nmol.l-1) up to the 21st day with the exception of temporary drop on day 4 and rise on day 7, insignificant compared to the -1st day. T4 concentrations of the control group displayed an intermittent increasing trend with the statistically insignificant peak after 36 h and on day 17, compared to the -1st day. After the 21st day controls revealed a sustained moderate increase while the experimental ewes displayed a decline of its concentrations until the 51st day.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
28.
The levels of oestradiol-17 beta (E2) in the blood plasma were evaluated in 15 boars exhibiting signs of sexual potency disorders and in 20 boars with no such disorders before and after i. v. administration of chorion gonadotropin (HCG). No significant difference (P greater than 0.05) was found in the E2 levels in the blood plasma of the boars of the two groups before HCG administration. Two hours after the i. v. injection of 500 I. U. of HCG, an insignificant increase in the basal levels of E2 was recorded, reaching on the average 28.9% in the boars with potency disorders and 38.8% in those with no potency changes. Neither were there any significant differences in the E2 levels determined after HCG treatment between the boars with and without sexual potency disorders. It is inferred from the results that deviations in E2 concentration in the blood obviously do not contribute significantly to disorders in the sexual potency of boars.  相似文献   
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