| Colibacillosis is an infectious disease caused by certain serotypes of pathogenic E.coli and toxins. This disease breaks out throughout the year and infects rabbits at all ages, especially the rabbits from weaning to 4 months. In order to investigate the effects of E. coli on Substantive Organs in rabbits deeply, we treated pups artificially infected by E.coli as the experimental subjects in this experiment. The distribution of CD14 in spleens of sick rabbits in different pathogenesis periods were detected by the damage index oxidation test of the sick pups’ Substantive Organs and immunohistochemistry(IHC). We reached the pathological damages of Pathogenic Escherichia coli to organisms in a new perspective, and provided a new clinical basis for further prevention of E. coli.In this experiment, 32 rabbits of 30~40 days were divided into a control group and a sicken group. Dope to the sicken group and normal saline to the control group by intraperitoneal injection of E.coli. We took 1cm3 pups’ each solid organ(heart, liver, spleen, lung, kidney) of 1,3,5,7 days frozen in liquid nitrogen, and stored at-80 ℃ refrigerator to detect the oxidative damage index. SOD, MDA and protein content of various organs were measured. We had analysis the indicators of the control and sicken groups as well as the change rule of the index during the onset of the incidence of different groups. Another 1cm3 spleens were fixed to 40 g/L paraformaldehyde after rush clean surface with saline water, then we can detect the distribution of pups spleens of CD14 via immunohistochemical method. To calculate the positive rate of trabecular CD14 of white pulp, red pulp, blood vessels and trabecular, then we can analyze and compare with the CD14 distribution of control group and the variation of positive rate of different set periods.Autopsy results: There was a large number of fibrin existing in their celiac and have a significant odor. There was a lot of fibrin outside the intestinal, the gut wall was bleeding and contents were jelly. Liver and lung had obvious bleeding and congestion phenomenon. Outside the spleen attached to a large number of external fibrin and congestion phenomenon has appeared in kidney in individual rabbits.Oxidative damage indicator results: The SOD value of Substantive Organs of sicken group was lower than the control group, and the sicken group showed that with the progression of the disease, the SOD activity appears in a trend of first increased then decreased. Liver had the lowest SOD activity on the first day. Heart and spleen had the lowest on the third day, while lung and kidney on the fifth day. In heart, there was a significant difference compared to the control group on the third day(P< 0.01), and liver had a difference compared to the control group(P< 0.05) on the first day, while spleen on the third day. Lung and kidney had a difference compared to the control group(P< 0.05) on the fifth day; Protein content of sicken group was higher than the control group, and the sicken group showed the trend of first increased then decreased with the progression of the disease. In heart, there was a difference compared to the control group on the third day(P< 0.05), while liver shown on the first day, kidney shown on the fifth day; Content of MDA of sicken group was higher than the control group, and the sicken group showed a trend that after the first increased and then decreased with the progression of the disease. Liver had the highest MDA content on the first day, while heart and spleen on the third day, and lung and kidney on the fifth day. Heart and spleen had a difference on the third day compared to control group(P< 0.05), while lung on the fifth day.Immunohistochemical results: there were four groups shown negative in control group, and the remaining 12 groups were positive. Onset groups were detected as positive, and the positive results were very obvious. There were a most number of distributions in blood vessels. Trabecular and white pulp were followed, while the red pulp had the less distributions. The relative amounts of immunohistochemical positive expressions in the pathogenesis of the third day and the fifth day were higher than the other periods. Analysis of CD14 expression data in spleen’s various parts showed that sicken group was higher than the control group, and the sicken groups showed the trend of first increasing then decreasing with the progression of the disease. There were higher expression levels on the third and fifth day. White pulp of the third day and the control group have differences(P< 0.05); Red pulp of the fifth day and the control group have differences(P< 0.05); Red pulp of the third day and the control group have significant differences(P< 0.01); Vascular and trabecular have significant differences, compared to the control groups of the first, third and fifth day(P< 0.01).Experimental results show that substantive organs oxidative damage indicators of healthy rabbits are affected after artificial infection of E. coli, and different organs have the greatest impact in the incidence of different periods that liver in the first day, spleen and heart in the third day, lung and kidney in the fifth day. Immunohistochemical results show that the sensitivity of CD14 of spleen in the pathogenesis increase, and in the third day the sensitivity is the highest, which is consistent with the oxidative damage results. Experimental results show that E.coli not only produces damage to the intestinal, but also has a certain degree of damage to the substantive organs. |
PDF Full Text Request