title: Performance traits and immune response of broiler chicks treated with zinc and ascorbic acid supplementation during cyclic heat stress.
abstract: This research was conducted to investigate the effect of supplementation of zinc (Zn) and ascorbic acid (AA) in heat-stressed broilers. A total of 160-day-old broiler chicks of approximately the same weight and appearance were divided into four treatment groups (control, T1, T2, and T3). Control group was fed a standard diet without any supplementation. T1 was supplemented with Zn at the rate of 60 mg/kg of feed, T2 was supplemented with 300 mg/kg of feed AA, and T3 was supplemented with combination of Zn and AA. From week 3 to 5, heat stress environment was provided at the rate of 12 h at 25 °C, 3 h at 25 to 34 °C, 6 h at 34 °C, and 3 h at 34 to 25 °C daily. The results revealed that feed intake, body weight and feed conversion ratio (FCR), and weight of thymus, spleen, and bursa of Fabricius improved significantly (P < 0.05) in T3 compared to the other treatments. Antibody titer against Newcastle disease (ND), infectious bursal disease (IBD), and infectious bronchitis (IB) increased significantly (P < 0.05) in T2 and T3 groups. However, total leucocytes count, lymphocytes, and monocytes increased (P < 0.05) in all treated groups compared to control. The results indicated that the supplementation of Zn or AA alone or in combination improved the performance and immune status of broilers reared under heat stress.
authors.affiliation: Faculty of Animal Husbandry & Veterinary Sciences, The University of Agriculture, Peshawar, Pakistan.
authors.forename: Naila
authors.initials: N
authors.lastname: Chand
authors.forename: Shabana
authors.initials: S
authors.lastname: Naz
authors.forename: Ajab
authors.initials: A
authors.lastname: Khan
authors.forename: Sarzamin
authors.initials: S
authors.lastname: Khan
authors.forename: Rifat Ullah
authors.initials: RU
authors.lastname: Khan
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D001205:Ascorbic Acid / Q000494:pharmacology / Q000627:therapeutic use*; D002060:Bursa of Fabricius / Q000187:drug effects / Q000254:growth & development; D002645:Chickens; D019587:Dietary Supplements; D004359:Drug Therapy, Combination; D004435:Eating / Q000187:drug effects; D018882:Heat Stress Disorders / Q000097:blood / Q000188:drug therapy* / Q000276:immunology* / Q000662:veterinary; D001351:Infectious bronchitis virus / Q000276:immunology; D007243:Infectious bursal disease virus / Q000276:immunology; D007958:Leukocyte Count; D009522:Newcastle disease virus / Q000276:immunology; D009929:Organ Size / Q000187:drug effects; D013154:Spleen / Q000187:drug effects / Q000254:growth & development; D013950:Thymus Gland / Q000187:drug effects / Q000254:growth & development; D015032:Zinc / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D000914:Antibodies, Viral; D015032:Zinc; D001205:Ascorbic Acid