title: Dietary calcium and phosphorus effects on broiler performance and the incidence of sudden death syndrome mortality.
abstract: Three experiments were conducted with broiler chickens to determine the effect of dietary Ca and P on growth, feed conversion, bone ash, and the incidence of sudden death syndrome (SDS) mortality. Trial 1 tested three rations [100% NRC (1984) Ca and P; 140% NRC Ca and P; and 140% NRC Ca and P to 3 wk and 100% NRC from 4 to 7 wk] in Ross x Ross males to 7 wk of age. Dietary Ca and P had no effect on body weight, feed conversion, bone ash, or leg problems, but SDS mortality was significantly higher in the two groups fed 140% Ca and P for 3 or 7 wk (2.83 and 3.33% SDS mortality, respectively). Trial 2 tested three diets (85% NRC Ca and P, 100% NRC Ca and P, and 140% NRC Ca and P) in mixed sex Arbor Acres x Peterson chicks to 7 wk of age. The lower level of Ca and P (85% NRC) significantly improved feed conversion (7 wk) and decreased bone ash only at 3 wk and serum Ca (7 wk). There was no effect of diet on SDS in this trial. Trial 3 tested two diets (85% NRC Ca and P or 100% NRC Ca and 85% NRC P) in Ross x Ross males to 9 wk of age. Six-week body weight was significantly reduced in the 85% NRC Ca and P diet but body weight was equal by 9 wk of age. No effects were observed for feed conversion, leg disorders, bone ash, or serum Ca. The SDS mortality was significantly increased in the chicks fed the 100% NRC Ca and 85% P diet compared to the 85% NRC Ca treatment. The results of these trials indicate that even slight deviations in dietary Ca and P beyond the NRC recommendations can create a metabolic imbalance in certain strains of broilers (Ross x Ross), which possibly increases susceptibility to SDS mortality.
authors.affiliation: Department of Poultry Science, North Carolina State University, Raleigh 27695-7608, USA.
authors.forename: S E
authors.initials: SE
authors.lastname: Scheideler
authors.forename: D V
authors.initials: DV
authors.lastname: Rives
authors.forename: J D
authors.initials: JD
authors.lastname: Garlich
authors.forename: P R
authors.initials: PR
authors.lastname: Ferket
mesh_terms: D000818:Animals; D001835:Body Weight / Q000502:physiology; D002118:Calcium / Q000097:blood; D002136:Calcium, Dietary / Q000494:pharmacology*; D002645:Chickens / Q000254:growth & development* / Q000502:physiology; D003645:Death, Sudden / Q000453:epidemiology / Q000662:veterinary*; D005260:Female; D015994:Incidence; D008297:Male; D016226:Phosphorus, Dietary / Q000494:pharmacology*; D011201:Poultry Diseases / Q000453:epidemiology* / Q000401:mortality*; D011897:Random Allocation; D013577:Syndrome
chemical_list: D002136:Calcium, Dietary; D016226:Phosphorus, Dietary; D002118:Calcium