Acth And LPS Challenge On The Blood Indexes And Hepatic Cholesterol Metabolism In PIGS

This study was aimed to investigate the blood and liver biochemistry parameters under two stress statuses in pigs. We hope to find the biological markers which response to the stress rapidly, then determine the degree of stress under different statuses, and improving the environment, the production of animals in industry. ACTH and LPS stresses were used in the first and second experiments.The Hematoxylin and eosin staining of liver tissue was used for detecting the degree of image of liver under these two stresses. Additionally, we adopted Western blot and PCR methods to elucidate the cholesterol metabolism in these two models. Five farms of pigs were selected in our third experiment, include different breeds, different body weight, and different environment. The biochemistry parameters, routine blood indexes, enzyme activity, hormones and amino acids were detected systematically.1Effect of adrenocorticotrophic hormone on growing pigs’metabolic status and immune functionSixteen Duroc×(Landrace×Large White) male pigs of similar age and weight (about20kg) were used in this experiment. Pigs were individually housed in pens (1×2m2) and fed twice a day with a commercial pig diet for growing pigs. Water was available ad libitum. Pigs were fitted with jugular vein catheters and randomly divided into control group and an ACTH group. The ACTH group were injected synthetic ACTH at a dose of1IU/kg of body weight intramuscularly at09:00am. The remaining pigs (n=8) received an equivalent volume of physiological saline at the same time.5mL blood was collected into tubes via the jugular vein at0,15,30,45,60,90and120min after administration of treatment for plasma, and then stored at-20℃until it was assayed. Plasma cortisol, ACTH, insulin, T3, T4and TNF-a concentrations were measured using commercial multispecies radioimmunoassay (RIA) kits. Using automatic biochemical analyzer to detecte plasma CK、LDH、ALT、 AST、AKP、γ-GT、Glu、TG、CHOL、LDL-CHOL and HDL-CHOL, each sample need0.5mL.2The different effect of ACTH and LPS injection on hepatic cholesterol metabolism in pigsTo investigate the different effect of ACTH and LPS injection in pigs,24male pigs at age of28days were used in this experiment. They were divided into four groups, Control group, ACTH group, LPS group, ACTH and LPS combine injection groups. The plasma cytokines such as cortisol and TNF-a levels all increased6hours after LPS injection (P=0.028and P<0.001respectively), and the expression of TLR2mRNA level in liver was significantly increased by three folds (P<0.001), the expression of TLR4has an increase trend compared with control group (P=0.081). In the present study, LPS treatment didn’t influence the plasma total cholesterol, LDL-C, triglyceride and VLDL content, though HDL-C content is significantly decreased. However, the cholesterol metabolism related genes were significant changed after LPS administration. The HMGCR, SREBP, CYP7al and CYP27al mRNA expression all significant decreased6hours after LPS injection, the ACTH and LPS combine injection group has the same trend, though the ACTH group has no change at the same time. These results indicate that LPS injection affects hepatic cholesterol metabolism in piglets, the ACTH has no significant effect on the piglets two days after injection, but ACTH can enhance the he sensitivity to the LPS.3Correlation Analysis between the physiological and biochemical indices in blood and breeding health status in different pig farmsSerum samples were taken from five pig farms. We select piglets, growing stage pigs and finishing stage pigs include DLW, DLWP, Huai-breed and Mi-breed in our research. Ten pigs of each group. Serum biochemistry parameters, routine blood indexes and enzyme activity were detected. Automatic biochemical analyzer(Olympus AU2700), Hematology Analyzer(HB7021, SINNOWA) and Enzyme linked immunosorbent assay (Elisa) were used respectively.The results showed good breeding conditions is positively correlated with the number of pig red blood cells, HDL-C and the number of lymphocytes, but negatively correlated with the number of neutrophils and TG. Good pens is positively correlated with the total cholesterol and LDL-C.The health status is positively correlated with the number of red blood cells and the hematocrit were positively correlated.Hemoglobin in the red blood cells have the function to carry the oxygen, so the number of red blood cells and hemoglobin levels were higher when pigs growing in good breeding and environment.