An improvement in productive and reproductive performance of aged broiler breeder hens by dietary supplementation of organic selenium.

This study was conducted to determine the optimum level of home-made selenium-enriched yeast (SeY) in the diet of broiler breeder hens and to compare the effects of this product with sodium selenite (SS) or Selemax (SM) on their productive and reproductive performance. A total of 150 broiler breeder hens were divided to six groups and hens in each group were received a basal diet containing no selenium (CG), 0.15, 0.30, 0.45 mg SeY/kg diet (SeY-0.15, SeY-0.30 and SeY-0.45, respectively), 0.30 mg SM/kg diet or 0.30 mg SS/kg diet for 15 successive weeks. The results showed that egg weight and production and hatchability rate were higher in SeY-0.45 compared to other groups (P < 0.05). Also, SeY-0.45 group led to lower embryonic mortality rate compared to CG and SS groups. Fertility rate and chick quality parameters were not affected by selenium supplementation during this period (P > 0.05). In conclusion, the dietary supplementation of home-made selenium, as an organic selenium source, can be used to improve the productive and reproductive performance in aged broiler breeder hens at 0.45 mg/kg feed.

Effect of salinity on biodegradation of polycyclic aromatic hydrocarbons (PAHs) of heavy crude oil in soil.

The spillage of crude oil in the soil damages the environment. Polycyclic aromatic hydrocarbons (PAHs) are one of the crude oil components that may be harmful for living organisms. PAHs can disappear from the environment by volatilization and biodegradation. The effect of different NaCl concentrations (0%-5%) on PAHs reduction from the heavy crude oil-contaminated soil was studied. Our results showed that increasing NaCl concentration in soil had decreasing effect on total crude oil and PAHs reduction. The biodegradation of total crude oil was higher in 0% NaCl (41%) while higher total PAHs reduction was observed in 1% NaCl (35%). The lower total crude oil and PAHs reduction were observed in 5% NaCl (12% and 8% respectively). Phenanthrene, anthracene and pyrene reduction were higher in 1% NaCl, while fluoranthene and chrysene reduction were higher in 0% NaCl.