Variations Of The Trace Elements, Anti-oxidate Indexes And Hormones In The Serum Of Dairy Cows With RFM

In order to study the mechanism of retention of fetal membranes (RFM) in dairy cows, the the concentrations of some constant and trace elements of the serum in dairy cows with and without RFM were detected with atomic absorption spectrophotometer; the activity of antioxidant indexes in placental tissue and serum was also determined with visible spectrophotometer; the levels of estrogen, progesterone and cortisol in the serum were measured by radioimmunoassay, after jugular blood samples were collected from the cows with similar feeding conditions and milk production at parturition and 12h after parturition. The purpose in the study is to analyse the correlation between the level of trace element ion and oxidative stress and to discover the mechanism of the RFM primarily.1, After analysis of concentrations of Ca, Mg, Na, and K in the serum of jugular vein, the results showed that the levels of the serum Mg and Ca in cows with RFM at parturition and 12h after parturition were significantly lower than those from control group (P <0.05), and there was no significant difference in the contents of Na and K between.the cows with and without RFM. The concentrations of K, Na Ca, Mg and P in the dairy cows RFM at parturition were higher than that at 12h after parturition, but there was no significant difference between those. The concentrations of Ca, Mg and P in the dairy cows with RFM at parturition were lower than that at 12h after parturition, but there was no significant difference between those either.2. After After analysis of concentrations of the serum Cu, Fe, Zn, and Mn of jugular vein, the result showed: the concentrations of the serum Mn, Zn and Cu in cows with RFM were very significantly lower than those in the cows of the control group (P<0.01), but the concentration of Fe in the serum of cows with RFM was significantly higher than that in the control group (P<0.01). The concentrations of Fe, Zn and Mn in the dairy cows with and without RFM at parturition were higher than that at 12h after parturition, but there was no significant difference between those. The concentrations of Cu in the dairy cows with RFM at parturition were lower than that at 12h after parturition, but there was no significant difference between those either.The result indicated that the trace element in the serum of the RFM became turbulence.3. The variety of anti-oxidate indexes such as total SOD(T-SOD), CuZn-SOD, Mn-SOD, GSH-Px, MDA, and hydroxyl radical (OH ?) in the serum of jugular vein were analyzed. The results showed that the activity of CuZn-SOD, Mn-SOD, T-SOD and GSH-Px were significantly lower in the cows with RFM than that in the control group (P <0.01), and the concentration of OH ?, MDA in the serum of RFM were significantly higher than that in the control group ( P <0.05). The result indicated that the cows with RFM were in a high Oxidative Stress state.4,. The variety of anti-oxidate indexes such as total SOD(T-SOD), CuZn-SOD, Mn-SOD, GSH-Px, MDA, and hydroxyl radical (OH ?) in the placenta tissue were detected.The results showed that the activity of CuZn-SOD and Mn-SOD and theT-SOD and GSH-Px were significantly lower than that in the control group (P <0.01), and the concentrations of OH ? ,MDA in the serum of cows with RFM were significantly higher than the normal group ( P <0.05).The result showed :the anti-oxidate ability of the placenta tissue in cows with RFM is not strong , and the anti-oxidative system can not eliminate the free radicals and metabolites effectively so that the placenta epithelial was injuried by oxygen free radicals , which caused RFM.5, After detection the concentrations of serum progesterone (P4), estrogen (E2) and cortisol.the results showed that:the concentrations of P4 in cows with and without RFM at parturition were lower than that at 12h after parturition, but there was no significant difference between them, and the concentration of the serum E2 in cows with RFM was higher than that in the control group(P <0.01);but it decreased sharply within 12h after parturition ,so it was in a lower level.The concentration of cortisol in cows with and without RFM was lower at parturition than that at 12h after parturition, but there was no significant difference between them., and the levels of cortisol in cows with RFM was higher that in the control group (P <0.01) at parturition and 12h after parturition. The results showed that: because of the lower level of the E2,and the contraction of the blood vessels in the placenta was inhibited ,and at the same time the high dgree of stress made more blood left in the peripheral vessels, so that the placenta was in a state of congestion .that is one of the reason s why the RFM happens more frequently.