title: Single and Combined Impacts of Vitamin A and Selenium in Diet on Productive Performance, Egg Quality, and Some Blood Parameters of Laying Hens During Hot Season.
abstract: A study was conducted using 162 Bovans laying hens to investigate the impacts of extra dietary vitamin A (0, 8000, 16,000 IU/kg), selenium (0, 0.25, 0.50 mg/kg), and their combinations on the performance, egg quality, and blood biological parameters of laying hens during summer months. Supplemental vitamin A up to 16,000 IU/kg diet significantly (P < 0.05) improved all productive traits studied except feed intake which increased with 8000 IU/kg diet compared with control. Feed intake and feed conversion of hens fed diet supplemented with selenium revealed high statistical (P = 0.001) differences. All egg quality criteria were not significantly (P < 0.05) affected by dietary vitamin A except albumin percentage and Haugh units, since Haugh unit score was gradually increased with increasing vitamin A level. Vitamin A-enriched groups showed significant (P < 0.05 and 0.01) decreases in plasma albumen, total lipids, and total cholesterol in respect to the unsupplemented groups. Compared with unsupplemented groups, total protein, albumin, total lipid, and total cholesterol were increased in selenium-enriched groups. There were no significant impacts of selenium treatments in layer diets on thyroid hormones and liver enzymes studied except alanine transferase (ALT) and thyroxin (T4), as compared with the control group. Hematological parameters were not affected by vitamin A treatment except PCV% which decreased with vitamin A supplementation. Hemoglobin and lymphocytes were increased with increasing dietary selenium level. In conclusion, the combined supplementary concentrations of vitamin A (16,000 IU/kg) and selenium (0.25 mg/kg) might be needed for better production and health of laying hens reared under heat stress conditions.
authors.affiliation: Department of Poultry, Faculty of Agriculture, Zagazig University, Zagazig, 44511, Egypt. m.ezzat@zu.edu.eg.
authors.forename: Mohamed E
authors.initials: ME
authors.lastname: Abd El-Hack
authors.affiliation: Department of Poultry, Faculty of Agriculture, Zagazig University, Zagazig, 44511, Egypt.
authors.forename: Khalid
authors.initials: K
authors.lastname: Mahrose
authors.affiliation: Department of Poultry, Faculty of Agriculture, Zagazig University, Zagazig, 44511, Egypt.
authors.forename: Ali A
authors.initials: AA
authors.lastname: Askar
authors.affiliation: Department of Poultry, Faculty of Agriculture, Zagazig University, Zagazig, 44511, Egypt.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Alagawany
authors.affiliation: Department of Animal Sciences, University College of Agriculture, University of Sargodha, Sargodha,, 40100, Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Arif
authors.affiliation: Institute of Animal Sciences, Faculty of Animal Husbandry, University of Agriculture, Faisalabad, 38040,, Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Saeed
authors.affiliation: School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang,, Sichuan, 621010,, People's Republic of China.
authors.forename: Farzana
authors.initials: F
authors.lastname: Abbasi
authors.affiliation: College of Animal Sciences and Technology, Northwest A&F University, Xianyang, 712100, Shaanxi,, People's Republic of China.
authors.forename: Rab Nawaz
authors.initials: RN
authors.lastname: Soomro
authors.affiliation: Department of Animal Nutrition, Faculty of Animal Husbandry and Veterinary Sciences, Sindh Agriculture University, Tando Jam, 70060,, Pakistan.
authors.forename: Farman Ali
authors.initials: FA
authors.lastname: Siyal
authors.affiliation: Institute of Animal Nutrition, Northeast Agricultural University, Harbin, 150030,, China.
authors.forename: Maria Tabassum
authors.initials: MT
authors.lastname: Chaudhry
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D002645:Chickens; D004032:Diet; D004531:Eggs / Q000032:analysis*; D012621:Seasons; D012643:Selenium / Q000008:administration & dosage / Q000032:analysis*; D014801:Vitamin A / Q000008:administration & dosage / Q000032:analysis*
chemical_list: D014801:Vitamin A; D012643:Selenium
keywords: Blood; Egg quality; Laying hens; Performance; Selenium; Vitamin A