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The effects of dietary boron on the ultimate shear force, shear stress, and shear fracture energy of the tibia, humerus, and radius from White Leghorn layers were investigated. The shear force, stress, and fracture energy of the bones were not affected by increasing levels of dietary boron during the last four weeks of egg production. The quantity of boron in meat and bone tissue samples increased with increasing levels of boron. The liver from birds fed 56 mg/kg boron contained 3.3 times more boron than the control birds, the breast 1.8 times, the thigh 2.7 times, and the bone tissue 2.4 times. The results suggest that it may be possible to add another marketing dimension to poultry products using boron as an additive for elderly people needing to combat brittle bones.

Commercial equipment used by the turkey industry at hatch sterilizes the germinal tissue of the claw with microwave energy and the beak tissue with infrared energy. This effectively trims the claws and beaks of the birds. Two strains of Leghorn chicks (1,200 each strain) were utilized to test this technique on chickens. Half were subjected to the claw reduction (RC) technique at hatch, and half retained intact claws (IC). The beaks of one-third of the birds in the claw treatments were reduced (BT) at hatch using the infrared technique, one-third were precision trimmed at 7 d, and one-third were not trimmed (IB). Body weight, weight gain, feed intake, feed conversion, mortality, and fearfulness were measured. Rearing followed standard commercial feeding and husbandry procedures. The RC birds had significantly lower BW, except from 3 to 6 wk, and had significantly lower feed consumption from 8 to 18 wk. The 1 d BT birds experienced significantly lower BW from 3 to 14 wk and ate less total feed by 4 wk. Mortality was less than 2.1% for all treatments. From 6 to 8 wk, fearfulness score (a subjective scale of 1 to 10) peaked at 8 to 10 for IC birds and 3 to 4 for RC birds. By 16 to 18 wk, fearfulness score subsided to 2 to 3 for RC and 6 to 8 for IC. Beak trimming and reduction of claw growth at hatch allowed pullets to be grown to sexual maturity on less feed and with a lower level of observed fearfulness using standard husbandry practices.

The effects of dietary nickel (0, 25, 50, 75, 100, and 150 mg/kg) on growth performance parameters and bone strength characteristics of female broiler chicks were investigated. Broilers were housed in either cages or floor pens. At 7 weeks of age, the shear force, stress, and fracture energy of the tibia and radius for both the floor and caged birds all increased but not statistically when the basal diet was supplemented with 25 milligram of dietary nickel per kilogram of feed (mg/kg). Dietary nickel had no effect on bird body weight, but the caged broilers (2420 g) were heavier than the floor birds (2128 g). Percent tibia bone ash, a measure of bone density, was not influenced by dietary nickel, but the tibia ash of the floor birds (40.1%) was greater than that of the caged birds (36.4%). Overall, the data suggest that there is an optimum amount of dietary nickel, near 25 mg/kg, that will have a positive influence on bone strength characteristics and performance of female broilers.

The effects of dietary nickel (0, 25, 50, 75, 100, and 150 mg/kg) on the bone strength characteristics and performance parameters of male broilers were investigated. Broilers were housed in either cages or floor pens. At 6 wk of age, the shear fracture energy of the tibia from the caged birds increased when the basal diet was supplemented with 25 mg of dietary nickel per kilogram of feed. The shear force, stress, and fracture energy of the radius from the caged birds also increased at 25 mg/kg nickel. Dietary nickel had no effect on bird body weight, but the caged broilers (2,161 g) were heavier than the floor birds (2,005 g). Nickel had no effect on the strength characteristics of the tibia from the floor birds. Percent tibia bone ash, a measure of bone density, was not influenced by dietary nickel, but the tibia ash of the floor birds was greater than that of the caged birds. Overall, the data indicates that adding 25 mg/kg of dietary nickel to a poultry diet will have a positive influence on bone strength characteristics and performance.

The purpose of this study was to investigate the effects of claw removal and cage design in laying hens during the course of a normal egg production period. Claw removal and cage design had significant effects on various production parameters as well as gonadal and adrenal steroids in caged laying hens. Declawed hens showed a significantly greater intensity of early egg production. They tended to consume less feed, weighed significantly less, and had significantly better livabiltiy than the intact controls. Furthermore, declawed hens demonstrated lower plasma corticosterone and higher plasma estradiol levels during the latter phases of the laying period. However, during the latter stages of the egg production cycle, foot condition was significantly poorer in declawed hens. No significant treatment effects were noted for overall egg production, egg weight, specific gravity, antibody response, or feather condition. Hens in low profile cages consumed significantly less feed than those in the high profile cages during the earlier stages of production, but this difference disappeared after 30 weeks of age. No significant cage effect was noted for overall egg production, egg weight, specific gravity, antibody response, or feather condition. Significantly lower plasma corticosterone concentrations were seen in the hens maintained in low profile cages during the latter stages of the production period.