Effects of Selenium and Vitamin E Injection During Transition period on Physiological Performance of Camels (Camelus dromedarius) and their Neonates Reared Under Semi- intensive System

Abstract

The objective of the study was to investigate the effects of selenium (Se) and vitamin E (Se + Vit E) injection during transition period on the physiological performance of dromedary camels and their neonates reared under semi- intensive system. The study was conducted during the period December 2013 to January 2015. Fourty clinically healthy camels (20 pregnant females of three local breed: Arabi, Kenani and Deali, age 7-11year, number of parities: 2-3. and 20 neonate camels) were used. The animals belonged to Camel Research Centre, Faculty of Veterinary Medicine, University of Khartoum. The Animals were maintained on grazing and browsing trees and shrubs in the vicinity of the camel Centre and occasionally received concentrate supplements and roughages with free access to fresh water. Time mated pregnant camels were divided into 2 equal groups (10 each), as control and treated group. The treated group was injected intramuscularly with 10 ml of a combination of Se and Vit E (0.6 mg/ml of sodium selenite and 80 mg/ml of vitamin E acetate, LABORATORIOS CALIER, Spain) three times: one month before parturition, at parturition and one month postpartum. The neonate camels were divided into 2 equal groups (10 each), group A represented neonates born from the control mothers and group B represented neonates born from the injected mothers. Blood samples were collected from the jugular vein three times: one month before parturition, at parturition and one month postpartum for the pregnant females and for their neonates at birth, day 7; then after 1, 2 and 3 months of age. Blood and serum samples were used to determine the haematological and biochemical parameters as well as hormones profile. Statistical analysis was performed using SPSS for Windows version 20.0. ANOVA tests were used to assess the significant differences between the groups. In Experiment 1, the changes in haematological, serum biochemical parameters and hormones profile (thyroid hormones and cortisol) in response to the Se + Vit E injection and transition period were observed in female dromedary camels. Injection of Se + Vit E during transition period caused a significant (P˂ 0.05) increase in haematocrit (Hct); however, the increase was not significant for haemoglobin (Hb) and total erythrocytes count (TEC), total leukocytes count (TLC) and differential leukocytes count (DLC). Serum proteins parameters (total proteins, albumin and globulins) increased significantly (P ≤ 0.05) in injected mothers. Injection of Se + Vit E during transition period caused a significant (P≤ 0.05) increase in serum- [Na+], [K+], [Clˉ], [Ca++] and [Pi]. Injection of Se + Vit E caused non significant increase in T4 levels with no effect on T3 levels. However, cortisol levels decreased in injected mothers. A significant (P˂0.05) increase in colostrum (48 hr postpartum) and milk production (6 months postpartum) observed in response to the intramuscular injection of Se + Vit E. Injection of Se + Vit E during transition period reduced the percentage of clinical mastitis (80% for control group and 30% for injected group). The transition period had no significant effects on the haematological, biochemical parameters and thyroid hormones and cortisol levels; however, fluctuations on thyroid hormones have been observed. In Experiment 2, the effects of Se + Vit E injection during transition period on growth performance, health status, haematological and biochemical parameters, thyroid hormones profile and cortisol levels of neonate camels as well as the effect of age were investigated. Injection of Se + Vit E during transition period resulted in a significant (P≤0.05) increase in BW (at birth until 3 months) and body weight gain (BWG) of neonate camels. Neither diarrhoea nor dermatophytosis or ring worm was observed in neonate camels born from injected mothers. In contrast the percentage of diarrhoea and dermatophytosis were 20% and 50% respectively in neonates born from control mothers. Neonate´s mortality rate reduced to 0% in neonates born from the injected mothers compared with 30% in neonates born from the control mothers. Intramuscular injection of Se +Vit E during transition period had no significant effect on haematological and serum biochemical parameters of neonate camels, except for [Pi], which increase significantly (P ≤ 0.05). Neonate camels born from the injected mothers showed a significant (P ˂0.01) increase in T4 levels; however, T3 levels tended to increase non significantly. Serum cortisol level did not change significantly in both neonates' groups. A positive correlation (P ˂0.001) was observed between the age of the neonate camels and BW, whereas the correlation (P ≤ 0.05) was negative for haematological parameters, total protein, globulins, [K+], [Cl-] and T3 and T4. It was concluded that intramuscular injection of 10 ml Se +Vit E (0.6 mg/ml of sodium selenite and 80 mg/ml of vitamin E acetate) during transition period improved the physiological performance, health status, colostrum and milk production and BWG of neonate camels by enhancing the antioxidants status of female camels and their neonates. The data obtained in the present study can be utilized to improve health and productivity of female camels during the critical periods (transition and postnatal periods), which associated with physiological oxidative stress; ultimately the mentioned improvement could be reflected positively on the national camel herd growth in Sudan.