The risk assessment of oxidative stress in postpartum dairy cattle

Background: Negative energy balance in cows will induce catabolism especially of lipids and the resulting rapid increase of free fatty acids (NEFA) in the blood stream increases the production of reactive oxygen metabolites (ROMs) and promote oxidative stress. Once the animal body is in an oxidative stress state, many molecules in the body may be peroxidized, accelerating the destruction of cells and causing damage to tissues or organs. This study conducted risk assessment of the oxidative stress caused by negative postpartum energy balance in cows by exploring the relationship between negative energy balance and oxidative stress. Materials, Methods & Results: This experiment randomly selected 120 cows at 14 to 21 days postpartum, from an intensive cattle farm in Heilongjiang province, China. Using a negative energy balance standard of β-hydroxybutyric acid (BHBA) greater than 1.2 mmol/L, nonesterified fatty acid (NEFA) greater than 0.4 mmol/L and glucose (GLU) less than three mmol/L, the cattle were divided into a healthy group of 74 cows and a diseased group of 46 cows. The oxidative stress indices of the experimental cows were measured and analyzed using the independent sample t test. Spearman correlation analysis and regression analysis were performed and by using the binary Logistic regression analysis to predict disease, the receiver-operating characteristic curve (ROC) analysis established diagnosis effect and boundary values. Compared with the healthy group, the levels of glutathione peroxidase (GSH-Px), catalase (CAT), vitamin E (VE), selenium (Se) and total nitric oxide synthetase (T-NOS) in the blood of dairy cows in the diseased group were significantly reduced and the level of malondialdehyde (MDA) was significantly increased. The study concluded that negative energy balance is associated with oxidative stress in cows and the blood levels of GSH-Px, CAT and Se can be used...

The relationship between insulin resistance and type II ketosis in dairy cows

Background: Cows in perinatal period are prone to ketosis, characterized by increased ketone bodies and decreased bloodsugar. Study found that cows with type II ketosis had higher blood glucose levels. This type of ketosis exhibits insulinresistance and impaired glucose tolerance that are similar to type 2 diabetes. The purpose of this study was to investigatethe role of insulin resistance(IR) in type II ketosis in dairy cows.Materials, Methods & Results: In one intensive cattle farm, eight cows with ketosis and eight healthy cows that were 14-21 days postpartum were selected. The plasma of experimental dairy cows was collected and tested for the concentrationof glucose concentration. Glucose tolerance of blood glucose levels in 120 min was used as the cut-off point to divide thedairy cows into three groups: the abnormal glucose tolerance ketosis group (TH), the normal glucose tolerance ketosis(TL), and the healthy control group. Simultaneously, the indexes of plasma liver function, oxidative stress, and insulinresistance were detected. The results showed that after intravenous glucose injection, there was no significant differencein blood glucose concentration between the TL and control group, while the blood glucose levels in the TH group werealways higher than in the other two groups. The insulin sensitivity index (RQUICKI) value was significantly lower in theTH group than in the other two groups. Liver function abnormalities in the TH group were more severe than in the TL andcontrol group. Oxidative stress was higher in the TH group than in the TL and control groups...

The relationship between insulin resistance and type II ketosis in dairy cows

Background: Cows in perinatal period are prone to ketosis, characterized by increased ketone bodies and decreased bloodsugar. Study found that cows with type II ketosis had higher blood glucose levels. This type of ketosis exhibits insulinresistance and impaired glucose tolerance that are similar to type 2 diabetes. The purpose of this study was to investigatethe role of insulin resistance(IR) in type II ketosis in dairy cows.Materials, Methods & Results: In one intensive cattle farm, eight cows with ketosis and eight healthy cows that were 14-21 days postpartum were selected. The plasma of experimental dairy cows was collected and tested for the concentrationof glucose concentration. Glucose tolerance of blood glucose levels in 120 min was used as the cut-off point to divide thedairy cows into three groups: the abnormal glucose tolerance ketosis group (TH), the normal glucose tolerance ketosis(TL), and the healthy control group. Simultaneously, the indexes of plasma liver function, oxidative stress, and insulinresistance were detected. The results showed that after intravenous glucose injection, there was no significant differencein blood glucose concentration between the TL and control group, while the blood glucose levels in the TH group werealways higher than in the other two groups. The insulin sensitivity index (RQUICKI) value was significantly lower in theTH group than in the other two groups. Liver function abnormalities in the TH group were more severe than in the TL andcontrol group. Oxidative stress was higher in the TH group than in the TL and control groups...(AU)