The objective of this study was to evaluate the effects of different levels of dietary ME on growth performance and carcass characteristics in two different strains of broiler chicken. A total of one thousand, 1-day-old A strain and R strain male chicks were randomly assigned into 8 treatments in a 2×4 factorial arrangement. They were fed iso-nitrogenic (CP 21%) crumbled diets formulated to contain metabolizable energy (ME) 2,950 to 3,250 kcal/kg in increment of 100 kcal/kg in the starter phase (1 to 21d) and iso-nitrogenic (CP 19%) pelleted diets containing same ME levels as in the finishing phase (22 to 38d). The body weight (BW) gain of chicks fed the lower ME diets (2,950 or 3,050 kcal/kg) were higher than those of the higher ME groups. The dietary energy level showed significant effects on feed intake and feed conversion rate (FCR) from 1 to 38 days of age (p<0.05). With the increment of dietary energy, feed intake tended to be reduced, whereas FCR was improved in the two strains of broiler chickens. The lowest FCR was observed at 3,250 kcal/kg diet groups in both of the two strains from 1 to 38 days of age. Feed intake and BW gain during 38 days were significantly affected by the strain factor. Increasing dietary energy up to 3,250 kcal/kg had no effect on the relative weights of breast meat and abdominal fat. The dietary energy and strains showed significant effects on the dressing percentage. There were no significant differences in various blood profiles except for GPT activity.

ObjectiveThis study was conducted to investigate the effects of dietary detoxified Rhus verniciflua sap (RVS) on production performance, egg quality, lipid fractions of egg yolk, liver and serum, and the profile of cecal microflora in laying hens.MethodsTwo hundred 52-week-old Hy-Line Brown layers were randomly divided into 4 groups with 5 replicates per group (2 hens per cage, 5 cages per replicate) and were provided with one of 4 experimental diets containing 0%, 0.05%, 0.1%, or 0.2% RVS, for 6 weeks. Due to unequal intervals of RVS doses, the interactive matrix language procedure of the SAS program was used to correct the contrast coefficients of orthogonal polynomials.ResultsThere were no differences in feed intake and egg weight among the groups. Egg production increased (linearly and quadratically, p<0.05) with increasing levels of RVS. Eggshell thickness increased (linear, p<0.05) as the level of RVS in diets increased. The levels of blood cholesterol and activities of glutamic-oxaloacetic transaminase and glutamic-pyruvic transaminase were not altered by dietary treatments. Increasing level of RVS increased (linear, p<0.05) the populations of cecal lactic acid bacteria. The content of yolk cholesterol decreased (linear, p< 0.05) with increasing levels of dietary RVS, although there were no significant differences in each lipid fraction of the liver.ConclusionThis study indicates that dietary RVS could improve laying performance and eggshell quality, and affect cecal lactic acid bacteria in a dose-dependent manner.

This experiment was conducted to investigate the effects of various levels of dietary protein on laying performance and egg quality in laying quail. A total of six hundred forty 7-week-old laying type Japanese quail were divided into four groups with eight replicates per group (20 birds per replicate) and fed four diets differing in dietary protein levels (18, 20, 22 and 24%) with isocaloric corn-soybean meal-based diets for 8 weeks. The results showed no significant differences in feed intake and egg weight among the groups. With an increase in dietary protein levels, the egg production and daily egg mass were linearly increased (P<0.05). However, there were no significant differences in eggshell thickness and Haugh unit. The dietary protein did not affect the blood levels of GOT, GPT, BUN, albumin, and creatinine. The ammonia concentration of intestinal digesta was not affected by the dietary treatments. The contents of hepatic triacylglycerol in the groups fed diets containing 20% protein or more were significantly reduced as compared with that of 18% CP group (P<0.05). Overall, this study showed that relatively high levels of dietary CP are needed to sustain the higher egg production and daily egg mass and to avoid the hepatic triacylglycerol accumulation in Japanese quail. (Howes, 1964;Shim and Vohra, 1984). Gropp and Zucker(1969)는 ME 2,600 kcal/kg인 사료에 ME 16%의 단백질만으로도 부 족함이 없다고 하였으나, Tanaka et al.(1966)은 2,800 kcal/kg 인 사료에 적어도 20%의 단백질이 필요하다고 하였으며,

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