The Impact Of Subclinical Ketosis On Clinical Morbidity, Dynamic Change Of Biochemical Indices And Immunity Function In Periparturient Dairy Cattle

Subclinical ketosis mainly occurs in high yield cows, with the feature of low blood glucose and hyperketonemia. The ketosis of dairy cows is due to negative energy balance that is caused by the dysbolism of carbohydrate and lipide, which leads to the accumulation of ketones in the blood and discharged from urine, milk and breath. As subclinical ketosis does not lead to obvious clinical symptoms, it can cause more serious potential hazards. Currently, there are few reports about the relationship of subclincal ketosis and antioxidant capacity, immunity function with a model of dynamic variation during transition period. This study was mainly about the impact of subclinical ketosis on incidence of some other desease, the fluctuation of antioxidant capacity and immunity function during transition period, which provided evidence for the prevention of disease in dairy cows.1The impact of subclinical ketosis on clinical morbidity of dairy cattle during transition period14subclinical ketosis cows were chosen from40holstein cows as the test group (1.0mmol/L≤BHBA<2.6mmol/L). The control group was paired according to age, expected calving date, milk yield and days in milk, BCS with14cows (serum BHBA <1.0mmol/L),and detected the corresponding cattle for NEFA and blood glucose, cortisol, the blood calcium. The result indicated that the incidence of mastitis in the test group was36%, while the control group was30%(P<0.05). The incidence of endometritis in the test group was4.5%,while the control group was0%(P<0.01).The percentage of retained placenta in test group was60%,while the control group was20%, the difference was significant (P<0.05).In the part of the detection of BHBA, it can be concluded that at the calving day and7th day postpartum, the concentration of BHBA in test group was higher than that in control group, the difference was very significant (P<0.01).Simultaneously, in the14th day postpartum, the test group was higher than that in control group, the difference was significant (P<0.05). The whole tendency can be described that decline after the first up, which can reach the peak at14th day postpartum. 2The impact of subclinical ketosis on biochemical indices of dairy cattle during transition period12subclinical ketosis cows were chosen from40holstein cows as the test group (1.0mmol/L≤BHBA<2.6mmol/L). The control group was paired according to age, expected calving date, milk yield and days in milk,BCS with12cows (serum BHBA <1.0mmol/L). Blood was simpled to centrifugate serum for the analysis of the levels of P-hydroxybutyric acid (BHBA), total antioxidant capacity (T-AOC), glutathion peroxidase(GSH-PX), superoxide dismutase (SOD), catalase (CAT), and malonaldehyde(MDA) in the serum. In the part of the detection of NEFA, the data showed us that the concentration of which was higher in test group than that in control group at the14th day postpartum, the difference was significant(P<0.05). While in the21st day postpartum, the concentration in test group was higher than that in test group, the difference was very significant (P<0.01). The whole tendency can be described that decline after the first up, which can reach the peak at7th day postpartum. Blood glucose in both groups declined in the calving day (0d),the difference was not significant(P>0.05); In the part of the detection of cortisol during peripartum period,which can be concluded that the concentration of which was higher in test group than that in control group at the7th and14th day postpartum. The difference is very significant (P<0.01). While in the21st day postpartum, the concentration in test group was higher than that in test group, the difference was significant(P<0.05), the trend of the changes in cortisol declined firstly and then rose.The level of GSH-Px in test group was higher than that in control group at the calving day(0d),the difference was very significant(P<0.01).In the14th day and28th day postpartum,the level of GSH-Px was higher in test group, the difference was significant(P<0.01).There was no significant in other period. The level of SOD was lower than control group in the14th day prepartum, the difference was very significant (P<0.01), and which was lower than that in7th,14th,21st and28th day postpartum either. The difference was very significant (P<0.01). The dynamic range of SOD in test group was higher than that in control group; The level of T-AOC in test group at7th day prepartum,7th day,21st day postpartum lower than that in control group, the difference was significant(P<0.05). The level of SOD was minimized to the lowest in the calving day(0d).Overall,the level of MDA was higher in test group than that in control group.The level of MDA in test group was higher in7th day prepartum,21th postpartum than that in control group. There was no significant difference in the aspect of CAT (P>0.05).In the14th day postpartum, the level of test group was lower than that in control group, the difference was significant (P<0.05).3The research of the change rules of immunity function of dairy cattle suffered from subclinical ketosis during transition period According to the day in milk(DIM), parity, body condition score(BCS>3.5),expected calving date,40dairy cows were selected as experimental animals. Based on the level of NEFA prepartum(NEFA>0.4mmol/L),and the standard showed in Test Ⅰ,12dairy cows were selected as test group, and another12dairy cows were selected as control group. The result demonstrated that the stimulation index (SI) of lymphocyte transformation was lower in test group than that in control group in the7th prepartum, the difference between two groups was very significant (P<0.01). The stimulation index in test group was significantly lower than that in control group at calving day (P<0.05).Overall, the SI decreased at parturition then ascended to normal level. The level of IgG in test group was lower than that in control group in14th day,7th day prepartum, the difference was very significant (P<0.01). The level in test group was significantly lower than that in control group at parturition (P<0.05).All over the whole tendency, the level began to decline prepartum until parturition and then ascended to normal level; The level of IL-2decreased at parturition and7th day postpartum, the level began to decline prepartum until parturition and then ascended to normal level; The level of L-selectin was lower in test group than that in control group in14th,21st day postpartum, the difference was very significant(P<0.01). In28th day postpartum the level was significantly lower in test group. The level of IFN-y began to decrease in14th day prepartum, the test group was significantly lower, which declined to the lowest level at parturition and then began to ascend.The speed and duration in test group was slower than that in control group. The level in test group was higher than that in control group at14th day postpartum, the difference between the two groups was significant (P<0.05).