Relative biological value of 1α-hydroxycholecalciferol to 25-hydroxycholecalciferol in broiler chicken diets.
This study was conducted to evaluate the relative biological value (RBV) of 1α-hydroxycholecalciferol (1α-OH-D3) to 25-hydroxycholecalciferol (25-OH-D3) in one- to 21-day-old broiler chickens fed calcium (Ca)- and phosphorus (P)-deficient diets. On the d of hatch, 450 male Ross 308 broiler chickens were weighed and randomly allotted to 9 treatments with 5 replicates of 10 birds per replicate. The basal diet contained 0.50% Ca and 0.25% non-phytate phosphorus (NPP) but was not supplemented with cholecalciferol (vitamin D3). The levels of Ca and NPP in basal diets were lower than those recommended by NRC (1994). 25-OH-D3 was fed at zero, 1.25, 2.5, 5.0, and 10.0 μg/kg, and 1α-OH-D3 was fed at 0.625, 1.25, 2.5, and 5.0 μg/kg. The RBV of 1α-OH-D3 to 25-OH-D3 based on vitamin D intake was determined by the slope ratio method. Results showed that 25-OH-D3 or 1α-OH-D3 improved the growth performance and decreased the mortality in one- to 21-day-old broilers. A linear relationship was observed between the level of 25-OH-D3 or 1α-OH-D3 and mineralization of the femur, tibia, or metatarsus. The RBV of 1α-OH-D3 to 25-OH-D3 were 234, 253, and 202% when the weight, ash weight, and Ca percentage of femur were used as criteria. The corresponding RBV of 1α-OH-D3 to 25-OH-D3 were 232 to 263% and 245 to 267%, respectively, when tibia and metatarsus mineralization were used as criteria. These data indicate that when directly feeding a hormonally active form of vitamin D as 1α-OH-D3 proportionally less is needed than when using the precursor (25-OH-D3) in diets deficient in Ca and P.
Department of Animal Science, College of Life Science, Shangqiu Normal University, Shangqiu, China.
J C
JC
Han
Department of Animal Science, College of Life Science, Shangqiu Normal University, Shangqiu, China.|College of Animal Husbandry and Veterinary Science, Henan Agricultural University, Zhengzhou, China.
G H
GH
Chen
Department of Animal Science, College of Life Science, Shangqiu Normal University, Shangqiu, China.|College of Animal Husbandry and Veterinary Science, Henan Agricultural University, Zhengzhou, China.
J L
JL
Zhang
Department of Animal Science, College of Life Science, Shangqiu Normal University, Shangqiu, China.|College of Animal Husbandry and Veterinary Science, Henan Agricultural University, Zhengzhou, China.
J G
JG
Wang
Department of Animal Science, College of Life Science, Shangqiu Normal University, Shangqiu, China.
H X
HX
Qu
Department of Animal Science, College of Life Science, Shangqiu Normal University, Shangqiu, China.
Y F
YF
Yan
College of Animal Science and Technology, Northwest A&F University, Yangling, China.
X J
XJ
Yang
Department of Biotechnology and Animal Science, National Ilan University, Taiwan.
Y H
YH
Cheng
D000821:Animal Feed / Q000032:analysis; D000818:Animals; D001682:Biological Availability; D002112:Calcifediol / Q000493:pharmacokinetics*; D002118:Calcium / Q000172:deficiency*; D002645:Chickens / Q000378:metabolism*; D004032:Diet / Q000662:veterinary*; D006887:Hydroxycholecalciferols / Q000493:pharmacokinetics*; D008297:Male; D010758:Phosphorus / Q000172:deficiency*; D011897:Random Allocation
D006887:Hydroxycholecalciferols; D010758:Phosphorus; D002112:Calcifediol; D002118:Calcium; C008088:alfacalcidol
1α-hydroxycholecalciferol; 25-hydroxycholecalciferol; broiler chicken; relative biological value