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R. Lindberg J. Monrad M. Vang Johansen N.
. Christensen P. Nansen 《Acta veterinaria Scandinavica》1993,34(2):183
The inflammatory host response to Schistosoma bovis in young goats was studied at necropsy by light microscopy 34 weeks after primary exposure to 3,000 cercariae (group B, n=6), 34 weeks after primary exposure to 3,000 cercariae followed by challenge with 2,500 cercariae at week 17 (group C, n=5), and 17 weeks after primary exposure to 2,500 cercariae, given on week 17 of the experiment (group D, n=6). Three goats served as uninfected controls. The faecal egg output had been minimal for 17 weeks prior to necropsy in groups B and C and only for the last 2 weeks in group D.Histological studies were carried out on the small intestine, liver, lung and spleen, and tissue egg counts were performed. In sections of the small intestine and liver, a panel of histopathological variables were quantitated to characterize the host response and differences between groups of animals were evaluated with one way analysis of variance. The mean tissue egg count in the small intestine was slightly but not significantly higher in group C than group B and about twice as high in group D (D vs B or C p<0.01). Group means of numbers of inflammatory foci per section of gut wall corresponded well with those of tissue egg counts, suggesting that the rate of inflammatory destruction of eggs did not differ markedly between the groups. Egg material was less commonly seen in granulomas of the small intestine in group B than in group D (p<0.01), suggesting lower passage of eggs through the gut wall during the later than during the earlier phase of patent primary infection. The frequency of eosinophil-rich hepatic inflammatory foci was much higher in group D than in the other groups (D vs B p<0.05, D vs C p< 0.01), and coincided with a high degree of blood eosinophilia in this group at the time of sacrifice. Challenged goats showed a significantly higher frequency of markedly fibrotic inflammatory foci in the liver and of liver granulomas with a marked giant cell component than goats of the other groups. Hepatic portal fibrosis was least prominent in animals with 17- week- old primary infections, implying a possible relation between this change and duration of infection. 相似文献
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Sodium selenite was mixed in a commercial pig food so as to increase the original selenium content (0.126 ppm) by 1.2 ppm. The supplemented food was given to 7 pigs during 78 days. A control group of as many pigs was given the non-supplemented commercial food. The pigs were killed, starting 4 hours after the last selenium-supplemented food had been given and then with intervals during the next 14 days. Small but significant increases of tissue selenium were noticed in liver and striated muscle as compared with the control animals. The kidneys showed no increase. 相似文献
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The influence of cottonseed oil and of linseed oil upon the fatty-acid composition of milk fat was each studied in one sow. Each oil was added to the basic diet in an amount of 6.3 % for two periods of the lactation. As cottonseed oil has a fatty-acid composition that is similar to that of the basic diet, the supplement with this oil will, in general, increase the same kind of fat in the diet. The linoleic-acid content in the milk fat will be nearly redoubled (11.7 % to 20.5 %) when the cottonseed oil is added. The supplement with linseed oil (of which linolenic acid constitutes about 58 %) to the food raised the linolenic-acid level in the milk fat from 1.1 % to 18.3 %. The increase of linoleic and linolenic acid is counterbalanced by a decrease of shorter fatty acids (G 14 and G 16 acids). The fatty-acid composition of the milk fat adjusts itself to the dietary changes within two or three days.By feeding a diet containing 16.7 % cottonseed oil to a sow, about 27 % linoleic acid was obtained in the sow’s milk fat.The influence of 30 hours of starvation upon the fatty-acid composition was studied in two sows. The content of G 18 acids rose during starvation and that of shorter acids (C14 and C16) diminished. 相似文献
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The effect of surgery (insertion of an ileo-caecal cannula) and a subsequent parenteral treatment with oxytetracycline on the ileo-caecal and rectal coliform populations in 7 Swedish Yorkshire castrates were studied. Samples were collected during surgery as well as 3, 7, 14 and 20 days post surgery. The diversity of the enteric coliform flora was initially high both in the ileo-caecal ostium and in rectum. No alteration in the diversity of the enteric coliform flora was observed following surgery and treatment with oxytetracycline. As the insertion of ileo-caecal cannulas did not affect the intestinal coliform flora this study gives support to the use of this technique to mirror processes in the small intestine of pigs. Further, the diversity of the enteric coliform flora was unaffected by the parenteral treatment with oxytetracycline. 相似文献
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A conjugate of oestradiol-17β and bovine serum albumin (BSA) has been prepared by the mixed anhydride method. The conjugate was characterized by u.v.-analyses and immunoelectrophoresis, and the number of moles of oestradiol-17β per mole of BSA was found to be 25. The conjugate was used for immunization of two sheep and one rabbit in order to elict antisera against oestradiol-17β. Antibodies could be detected in all three animals after 5–16 weeks depending on the route of immunization. The antiserum from one sheep could be used in a radioimmunoassay system for oestradiol-17β in a dilution of 1:5000 and was found to cross-react with oestrone and oestradiol-17α to a lesser extent than another antiserum against oestradiol-17β. 相似文献
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Blood Se of adult horses was 26.1, 25.8, and 27.0 ng/ml (mean values at 3 farms), where the Se of food was about 20 ng/g dry substance. Experimental adult horses which received about 41 ng Se/g food showed 45.3 ng/ml blood.At low Se intake suckling foals show higher blood Se than mares, but with high Se intake, the opposite will occur. This is reflected in milk Se, which raises but slowly with rise of mare’s blood Se.Se in blood plasma and in blood corpuscles is on the same level. The effect of various dose levels of Se on blood Se was studied: From 1.5 to 6 mg Se/week, blood Se rose rather linearity; 18 and 30 rag Se/week gave but slightly more effect than 6 mg. 相似文献