A 2×2 factorial experiment was conducted to study the effect of dietary calcium and non-phytate phosphorus (nPP) imbalance on calbindin and NaPi-IIb mRNA levels in the small intestine and tibia parameters of broiler chicks. One hundred and forty four 1-d-old Arbor Acres male broiler chicks were divided into four treatments consisted of six replicates with six chicks each. The two dietary calcium levels were 1.10% and 0.60%, and two dietary nPP levels were 0.50% and 0.27%. Results showed that a high Ca/nPP ratio diet (4.07:1) significantly depressed feed intake and weight gain of broilers (p<0.05), but a lower Ca:nPP ratio (1.2:1) had no influence (p>0.05). Low-Ca with low-P diet resulted in low tibia minerals and tibia breaking strength of broilers, and all the tibia parameters were further decreased when the dietary ratio of Ca to P was relative higher. Low dietary Ca or P up-regulated the calbindin and NaPi-IIb mRNA expression levels. Low Ca with normal P diet up-regulated duodenal calbindin mRNA expression level to the greatest extent. Low P with a normal Ca diet significantly enhanced NaPi-IIb mRNA expression level to the highest extent. These results suggest that the calbindin and NaPi-IIb mRNA expression were enhanced by the imbalance between dietary Ca and nPP, and their expression were not only influenced by Ca or nPP level, but also the ratio of Ca:nPP.

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The objective of this research was to evaluate effects of partial replacement of trace mineral (Cu, Mn, Zn) sulfate by methionine hydroxy analog (MHA) chelates on laying performance, egg quality, enzyme activity and mineral retention in layers. Laying hens (Hyline Brown) of 37 weeks old were fed with 4 different diets with organic or inorganic trace mineral supplementations at equal levels.

The aim of this study was to investigate the influence of mineral sources on broiler breeders and their offsprings. Broiler breeding hens were fed with diets containing either organic or inorganic trace minerals at equal levels, i.e., (1) control group was fed with basal diet supplemented with inorganic trace minerals; (2) OZ group was fed with organic Zn instead of sulfate; and (3) OTM group was fed with organic Cu, Mn, Zn, and Se instead of inorganic sources. Results indicated that OTM supplementation decreased plasma cholesterol and triglyceride and increased yolk triglyceride via increasing high-density lipid protein cholesterol and decreasing low-density lipid protein cholesterol and very low-density lipid protein (VLDL) in plasma. OZ diets decreased plasma cholesterol and triglyceride mainly by reducing VLDL concentration. For control group, increased lipid concentrations resulted in increased lipid peroxidation in serum and malondialdehyde retention in yolk. Zn retention was not affected. Otherwise, OZ diet was observed to decrease Cu in yolk and albumen. While for OTM group, albumen Cu, albumen Se, and hepatic Se of hatched chicks were increased, but yolk Cu was decreased. Moreover, organic mineral supplementations improved broilers' growth performance. In conclusion, organic mineral supplementation in breeders' diets protected breeders from lipid peroxidation, increased egg nutrition retention, and benefit for growth of broilers.

Effects of maternal and posthatch dietary oils and vitamin E (VE) on antioxidant capability and muscle quality of the progeny broilers were studied. Two-factor experiment was designed, there were two main effects, one was oil source, the other was VE level, diets were as follows: corn oil (CO) ＋20 mg/Kg VE, fish oil (FO) ＋20 mg/Kg VE, CO＋ 100 mg/Kg VE and FO＋ 100 mg/Kg VE. The results showed that: (1) Higher level of VE in maternal and posthatch diets also significantly reduced drip loss of breast meat of the progeny broilers, but increased meat MDA significantly, decreased meat SOD activity significantly, besides, there was an interaction trend (P＝0.06) between oil source and VE level on meat MDA, FO group with higher VE appeared the highest MDA content in breast meast. These findings suggest that diet with FO need more antioxidant to protect from oxidation, but FO oil with higher VE in maternal and posthatch diets may bring about meat deterioration to the progeny broilers.