Dietary calcium and phosphorus effects on broiler performance and the incidence of sudden death syndrome mortality.
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.
Scheideler
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Department of Poultry Science, North Carolina State University, Raleigh 27695-7608, USA.
Rives
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Garlich
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Ferket
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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
D002136:Calcium, Dietary; D016226:Phosphorus, Dietary; D002118:Calcium