• Title/Summary/Keyword: 강 석

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Effects of Dietary Granular Ark Shell Partially Replacing Limestone on Laying Performance and Eggshell Quality in Aged Hens (산란사료 내 석회석에 대한 고막조개 패분의 부분 대체 급여가 산란후기의 난 생산성 및 난각질에 미치는 영향)

  • ark T. S.P;Ryu S. J.;Kim S. K.;Ahn B. K.;Kang C. W.
    • Korean Journal of Poultry Science
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    • v.31 no.3
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    • pp.177-185
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    • 2004
  • This experiment was conducted to examine the dietary effects of local granular ark shell(GAS) replacing limestone on egg shell quality in aged hens. A total of 200 Hy-Line Brown layers of 54-weeks-old were allotted into four treatments with five replications each. They were fed control(limestone only) 1% GAS, 2% GAS and 3% GAS diets for 6 weeks. GAS was substituted for coarse-type limestone at 0, 1, 2 or 3% of diet on weight basis. Particle sizes of limestone and GAS were within the ranges of 2~4 mm in diameters. In vitro HCl solubility of GAS was significantly lower(6.27 vs. 7.90%) compared to that of limestone(p < 0.05). The dietary treatment did not affect feed intake and egg production rate of the birds. Egg shell strength and thickness tended to be improved for birds fed the diets containing higher levels of GAS. The average egg shell strength and thickness of 2 or 3% GAS groups were significantly greater than those of the control (P < 0.05). The Tibial ash content of birds from 3% GAS group increased significantly as compared to that of the control. Tibial breaking strength, however, was not affected by the dietary treatment. Serum Ca and P contents of the birds were also not different among the dietary treatments. In conclusion, locally prepared GAS can be used as a calcium source in aged layer diet.