INTERACTION EFFECTS BETWEEN DIETARY VITAMIN E SUPPLEMENTATION AND ENDOGENOUS ANTIOXIDANT ENZYMES OF DIFFERENT RABBIT GENETIC RESOURCES ON SOME GROWTH PERFORMANCE, VITAMIN E CONTENTS AND OXIDATIVE STABILITY DURING SUMMER SEASON | ||||
| Journal of Productivity and Development | ||||
| Article 6, Volume 18, Issue 1, January 2013, Page 57-75 PDF (559.69 K) | ||||
| Document Type: Original Article | ||||
| DOI: 10.21608/jpd.2013.42550 | ||||
 View on SCiNiTO | ||||
| Authors | ||||
Samia Meshreky  1; Mervat Arafa1; Salah Gad Alla1; Hasan Aboul-Ela2; Samya Ibrahim1; Mohamed Abo-Warda1
| ||||
| 1Animal Production Research Institute, Dokki, ARC, Egypt. | ||||
| 2Samya E. Ibrahim and Abo-Warda M.A. Animal Production Research Institute, Dokki, ARC, Egypt. | ||||
| Abstract | ||||
| The current study was initiated to explore the effect of the relationship between dietary vitamin E at levels; 40 (control), 80, or 120 mg/kg diet, and male and female of two rabbit breeds (exotic; V-line vs. native; Gabali) and their respective effect on some growth performance, carcass traits, and α-tocopherol contents and the activities of endogenous antioxidant enzymes (glutathione peroxidase; GSH-Px, superoxide dismutase; SOD, and catalase; CAT), lipid oxidative stability (TBARS) of the hind legs' muscle kept frozen (30 or 60 days at -20ºC). One hundred-fifty-six week old rabbits of both genotypes (allocated for each vitamin E level and sex (13 male or 12 female rabbits)), were distributed among the 12 experimental treatments. At the end of experiment, 36 samples from hind legs' muscle (3 animals/ dietary vitamin E levels/ breed/ sex) were used in the study of meat quality traits. Results indicate that the estimated THI values were 30.66, 29.32 and 30.21 during the experimental period (June, July and August) with average 30.063, these values indicating exposure of rabbits to severe heat stress. Body weight at 16 weeks of age, daily weight gain, the best feed conversion ratio, slaughter weight and hot carcass weight tended to increase significantly (P˂0.001) with increasing dietary vitamin E levels. Increase in dietary vitamin E was associated with a linear increase in α-tocopherol content of the muscle, delayed lipid oxidation (19.36 or 43.17 vs.57.43±0.468 ng/g in 120 or 80 vs. 40 mg vitamin E/kg diet supplemental groups) and increase in antioxidants' enzymes activity. Positive correlations between α-tocopherol deposited in muscle and GSH-Px and CAT activities (r= 0.229 and 0.278; P<0.05) and SOD activities (r= 0.186) were found. However, negative correlations were observed between TBARS and GSH-Px, SOD (r= -0.199, -0.129) and CAT activities (r= -0.232; P<0.05). The rabbits genotype (V-line vs. Gabali breed) had no significant effect on some growth performance, however, V-line rabbits had significantly higher slaughter weight, hot carcass and dressing percentage, but lower plasma α-tocopherol levels compared to the Gabali rabbits. V-line breed had higher significantly (P<0.0179) α-tocopherol content (1.667 vs. 1.537±0.046 µg/g) in muscle and lipid oxidative stability (39.52 vs. 40.64±0.382; P<0.0681), however, lower GSH-Px and CAT activities as compared to Gabali breed. Male rabbits had significantly higher daily weight gain, better feed conversion ratio value and insignificantly highest in dressing percentage than female rabbits. Significant difference between the male and female rabbit in against oxidation in frozen meat samples (38.48 vs. 41.5±0.382 ng/g). Male rabbits have lower endogenous antioxidant enzyme activities than the female. Prolonged storage decreased (P˂0.0001) α-tocopherol content of the hind legs' muscles, the activities of endogenous antioxidants' enzymes and lipid oxidative stability. Conclusively, adding a high level of vitamin E (120 mg/kg diet) to alleviate some of the impact of heat stress on different genotype rabbits, extra supplemental vitamin E, rabbit genotype and sex have a clear effect on meat quality as it increased the α-tocopherol content and lipid oxidative stability of the meat, during summer season. | ||||
| Keywords | ||||
| growing rabbit; Vitamin E; genotype; Antioxidant enzymes; oxidative stability; summer months heat stress | ||||
|
Supplementary Files
|
||||
|
Statistics Article View: 138 PDF Download: 294 |
||||
