title: Changes in dimensions and mechanical properties of bone in chicks fed high levels of niacin.
abstract: Tibia dimensions and mechanical properties were determined in White Leghorn cockerels that had been fed from 0.1 to 2.0% niacin as a supplement to standard poultry diets. Four experiments of from 20 to 38 days were conducted. No significant differences due to niacin were found in weight gain, feed consumed or feed:gain ratios. Decreases in the exterior (P < 0.009) and interior (P < 0.015) diameters of the major axes of the tibiae were found at 0.75-2.0% niacin. Exterior (P < 0.005) and interior (P < 0.001) diameters of the minor axes of the tibia were decreased at levels of 0.75 and 1%. Changes occurred in lateral wall thickness of chicks fed 0.75% niacin for 20 days (P < 0.004) and 38 days (P < 0.023) and in anterior wall thickness of 6-month-old chickens fed 1.0% niacin for 28 days (P < 0.001). Ultimate force was decreased in young chicks fed 1.0 and 1.5% niacin (P < 0.014) and 6-month-old White Leghorn chickens fed 1.0% niacin (P < 0.004). The addition of high levels of niacin to chick rations resulted in changes in dimensions, bone strength and susceptibility to fracture.
authors.affiliation: Department of Food Science and Human Nutrition, University of Hawaii, Honolulu 96822, USA.
authors.forename: N E
authors.initials: NE
authors.lastname: Johnson
authors.forename: X L
authors.initials: XL
authors.lastname: Qiu
authors.forename: L D
authors.initials: LD
authors.lastname: Gautz
authors.forename: E
authors.initials: E
authors.lastname: Ross
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001696:Biomechanical Phenomena; D002645:Chickens; D004435:Eating / Q000187:drug effects; D005527:Food, Fortified; D008297:Male; D009525:Niacin / Q000008:administration & dosage / Q000633:toxicity*; D011897:Random Allocation; D013977:Tibia / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology
chemical_list: D009525:Niacin