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Abstract Summary:Optimal transition buffaloe health is the key to success in the subsequent lactation, and increasing attention has been focused on management and nutritional practices that support it. Physiological changes during the transition Hanan Kamal PHD thesis period alters the efficiency of the immune system, making the animal more susceptible to infectious diseases with subsequent impairment of reproductive performance. Pregnancy and early lactation are stressful stages accompanied with increased metabolic activities and energy demand these stages are also accompanied by high energy and oxygen demand which may lead to an increase in the level of oxidative stress and development of metabolic and reproductive disorders in pregnant water buffaloes The appropriate inclusion of vitamin E and Selenium for buffaloes is important for optimizing the health of lactating and periparturient buffaloes. Less research work has been done to explore the role of oxidative stress and effects of antioxidant supplementation during the transition period in water buffaloes. The present research, therefore, aimed to investigate the oxidative stress indices in blood and milk and some metabolic indicators during periparturient period and effects of vitamin E and Se supplementation on them. The present study was carried out on 22 healthy, lactating, primi or pleuriparous buffaloes, with average age of 2-10 years old from farm related to the Faculty of agriculture, Quena governorate. The selected pregnant buffaloes were divided into 2 experimental groups Group I animals served as negative control and did not receive any treatment during periparturient period and Group II Treated group), buffaloes were received intramuscular injection of Viteselline (40 mL) containing 150 mg K-tocopherol acetate (Vit E) and 1.67 mg of sodium selenite per mL weekly starting from 8 weeks before parturition and lasted until 4 wk after calving.Hanan Kamal PHD thesis These buffaloes in both group were sampled with 2 weeks interval starting 8 weeks before parturition and after parturition weekly sampling was done till 4 weeks postpartum Heparinized blood samples, serum and hemolysate were collected from all buffaloes in all groups, stored at -20° C till the time of biochemical analysis; also milk samples were collected starting from parturition day and simultaneously with blood sampling from all buffaloes in all groups. The biochemical parameters included the following measurements:- 1- Blood serum calcium mg % 2- Blood serum phosphorus mg % 3- Blood serum magnesium mg % 4- Blood serum glucose mg % 5- Blood serum total lipids mg % 6- Blood plasma for measuring vitamin E (jg/ml), catalase (U/L), malondialdehyde (nmol/ml) and nitric oxide (jmol/L). 7- Erythrocyte hemolysate for measuring hemoglobin, SOD (U/mg Hb), and GSH-px (mU/mL). 8- Milk fat %, protein %, MDA (nmol/ml) and vitamin E (jg/ml).. The obtained results revealed the following facts: • Regarding clinical examination there were no abnormal clinical signs noticed on buffaloes in all groups during the experimental period. • Gradual decrease in the levels of blood serum calcium, phosphorus, magnesium, glucose and total lipids towards parturition then gradual increase within the normal ranges after parturition. Hanan Kamal PHD thesis.In both groups, NO, MDA concentrations increased at calving and decrease after parturition. Concentrations of NO, MDA decreased in the treated group and tended to increase in the control group. The lower MDA blood concentrations of treated buffaloes in the 2 wk after calving compared with those of control cows suggested that vitamin E has a role in recovering from oxidative stress. • Mean values of antioxidant enzymes activities decreased gradually before parturition in both groups and reached its lowest value at the day of parturition. After parturition gradual and significant increase was observed especially in treated group. • The vitamin E concentration in the blood was greater in the treated group starting from four weeks before calving. In the control group vitamin E concentrations start to decrease in the 6 wk before parturition. In both group, vitamin E concentrations (Lg/ml) decreased at calving (control group, x = 0.96; treated group, x = 1.94) and increased after calving gradually till reach (control group, x = 1.53; vitamin E group, x = 2.80) one month after calving. • Concentrations of MDA in both groups were high in the first milking and decreased in the following period. Vitamin E had a positive effect on MDA concentrations in milk. • Vitamin E concentrations in milk tended to be greater in the treated buffaloe group compared with control group. Treatment alone had a significant effect on milk vitamin E concentration. Hanan Kamal PHD thesis.Positive correlation was observed between blood MDA and NO. Negative correlation was observed between blood MDA, catalase, SOD, GSH-px and vitamin E, Positive correlation was observed between Vit E, MDA in serum and milk. • Finally it could be concluded that supplementation of the animal with antioxidants, like vitamin E and Se has beneficial effects, as evinced from changes in different oxidative stress parameters and decrease in plasma oxidants level. |