EFFECT OF ANTIOXIDANT SUPPLEMENTATION IN DIETS OF ROOSTERS DURING THE POST-PEAK PHASE ON REPRODUCTION AND PRODUCTION CHARACTERISTICS OF OFFSPRING

Dietary supplementation of spirulina and canthaxanthin boosts laying performance, lipid profile in blood and egg yolk, hatchability, and semen quality of chickens

This study examined the impacts of dietary spirulina (SP) and canthaxanthin (CX) supplementation to laying hens on reproductive performance and cock's semen quality evaluation. Three hundred and sixty of indigenous Sinai chickens (300 hens + 60 cocks), 48-weeks-old, were randomly divided into five treatments; a control and four supplemented (0.6 g SP mg/kg, 0.8 g SP mg/kg, 6 mg CX/kg diet, and 8 mg CX/kg diet) with six replications of 10 females and 1 male per treatment for laying trial and 1 male for semen evaluation. The animals were fed with experimental diets for 12 weeks. Supplementing 6 mg CX/kg diet led to an increase in the final body weight and egg production traits, while 8 mg CX/kg diet resulted in an improving feed conversion ratio. Supplementation of 0.6 g SP mg/kg or 6.0 mg CX/kg diet resulted in the highest egg production. The heaviest egg weight and egg mass were induced by 0.8 g SP mg/kg. Eggs laid from hens fed 0.6 g SP/kg diet had a higher concentration of cholesterol than those fed 0.8 g SP/kg and those fed 6.0 and 8.0 mg CX/kg. Cocks fed 6 mg CX/kg and those fed 0.8 g SP/kg diet had the greatest sperm concentration. The supplementation of 0.8 g SP mg/kg diet or both 6 and 8 mg CX/kg diet enhanced hatchability. So, dietary spirulina (0.8 mg/kg) and canthaxanthin (6 mg/kg) supplementation to Sinai laying hens and cocks could be used to improve productive and reproductive and performance.

Paternal Dietary Methionine Supplementation Improves Carcass Traits and Meat Quality of Chicken Progeny

The effects that maternal dietary methionine have on progeny have been reported on broilers. However, the paternal effects are not known, so the current study was conducted to explore the influences of paternal dietary methionine (Met) have on progeny carcass traits, meat quality, and related gene expressions. A total of 192 hens and 24 roosters from Ross parent stock at 36 weeks of age were selected. From week 37 to 46, the roosters were allocated to two groups with three replicates of 4 cocks each, (control, 0.28% Met), and methionine group (MET group, 0.28% Met + 0.1% coated Met). The results revealed that, although the heavier live body weight in progeny at day 49 of control group compared to MET group (p < 0.05), the relative eviscerated yield and relative thigh muscle yield were higher in MET group (p < 0.05); but the relative abdominal fat was lower (p < 0.05). In thigh and breast muscles, a positive response of pH_{24 h} value, shear force (g) and drip loss (%) were observed in MET group (p < 0.05). The lightness (L) and redness (a) were increased (p < 0.05) in breast muscles of MET group, while only the redness (a*_{24 h}) and yellowness (b*_{24 h}) were increased (p < 0.05) in thigh muscles of MET group. The gender has a significant (p < 0.05) effect on carcass traits and muscle redness (a*), where these traits improved in males, and no interaction between treatments and gender were observed for these results. The expression levels of PRKAG2 and PRDX4 supported the changes in muscle pH, with these up-regulated in thigh and breast muscles of MET group, the PPP1R3A gene supported the changes in pH value being down-regulated (p < 0.01) in these same muscles. The BCO1 gene expression was consistent with the changes in meat color and was up-regulated (p < 0.01) in thigh muscles of MET group, consistent with the changes in b* color values. Finally, it was concluded that the supplementation of 0.1% Met to rooster diets could improve carcass characteristics and meat quality of progeny.