Development of bone in chick embryos from Cobb 500 breeder hens fed diets supplemented with zinc, manganese, and copper from inorganic and amino acid-complexed sources

Sources of Zn, Mn, and Cu (IZMC) as sulfates or as amino acid complexes (OZMC) were used to supplement Cobb 500 breeder hen diets. Experimental treatments consisted of diets supplemented with 1) 100, 100, and 10 mg/kg of Zn, Mn, and Cu, respectively, from IZMC (control); 2) 60, 60, and 3 mg/kg of Zn, Mn, and Cu, respectively, from IZMC plus 40, 40, and 7 mg/kg of Zn, Mn, and Cu, respectively, from OZMC (ISO); and 3) a diet with 100, 100, and 10 mg/ kg of Zn, Mn, and Cu, respectively, from IZMC as in control plus 40, 40, and 7 mg/kg of supplemental Zn, Mn, and Cu from OZMC (on top). Ten replications of 20 females and 2 males were used per treatment. Eggs from breeders at 30, 40, 50 and 60 wk of age were incubated, and 5 embryos per replicate were collected at 10 (E10), 14 (E14), and 18 (E18) d of incubation. Midshaft width and calcification were measured for left tibia and femur stained with Alcian Blue and Alizarin Red S. At hatch, the left tibia of 5 chicks per replicate was sampled for histological evaluation of the diaphysis and distal epiphysis. Feeding the ISO treatment compared with the control diet increased the Zn (P < 0.05) but not Mn and Cu content of the yolk and albumen blend. At E14, the ISO and on-top treatments had a trend to increase tibia calcification at the rates of 1.6 and 1%, respectively (P < 0.1). The E18 ISO and ontop treatments had 2% thicker tibia compared with the control, regardless of hen age (P < 0.05). Also, at E18, calcification of tibia and femur was higher from hens fed the on-top treatment (P < 0.05). The chicks from the ISO and on-top groups had increased tibia moment of inertia (P < 0.01) at day of hatch. Broiler breeder hens consuming OZMC associated with IZMC produced embryos and hatching chicks with improvements in selected bone mineralization parameters.