ABSTRACT. The aim of studywas to compare efficacy of 1-α(OH)D3 alone or in combination with phytase and 1-α(OH)D3 in combination of phytase and different concentration of cholecalciferol on performance, tibia parameters, andplasma minerals of quails fed Ca-P deficient diet. A total of 280 mixed sex 5-d-old quails were allocated to 7 treatments with 5 replicates. The vitamin supplement which incorporated to basal diet did not contain cholecalciferol. The dietary treatments were as follows: Ca-P deficient diet (basal diet); basal diet + 500 FTU phytase/kg of diet; basal diet + phytase + 5 μg of 1-α(OH)D3 kg-1 of diet;basal diet + phytase + 5 μg of 1-α(OH)D3 and 250, 500, 750 and 1,000 IU of cholecalciferol kg-1of diet. The highest final body weight and the best feed conversion ratioobtained in the group supplemented with 1,000 IU cholecalciferol kg-1 of diet (p < 0.05). Supplementation of 1-α(OH)D3 alone or in combination with phytase and phytase and different concentration of cholecalciferol could improve tibia parameters (p < 0.05). In conclusion, supplementation of 1-α(OH)D3 alone to Ca-P deficient diet could maximize tibia mineralization, whereas it couldn't maximize performance, performance criteria were maximized by supplementation of 1,000 IU cholecalciferol kg-1 of diet.

ABSTRACT. This experiment was conducted to examine the effects of 1-α(OH)D3 alone or in combination with different levels of cholecalciferol on performance, and tibia parameters of one-d-old male broilers fed a tibial dyschondroplasia (TD)-inducing diet. A total of three hundred male broilers were randomly allocated to 5 treatment groups with 4 replicates. The dietary treatments consisted of TD inducing diet, TD inducing diet supplemented with 5 μg per kg of 1-α(OH)D3; TD inducing diet supplemented with 5 μg per kg of 1-α(OH)D3 and 1,500; 3,000 or 5,000 IU cholecalciferol kg-1 of diet. At 42 d of age, broiler chickens fed diets containing 1-α(OH)D3 and 1,500 IU cholecalciferol kg-1 of diet had higher body weight (p < 0.05). In the complete experimental period the best FCR and the highest daily weight gain were obtained in broilers supplemented with 1-α(OH)D3 and 1,500 IU cholecalciferol kg-1 of diet. Broilers supplemented with 1-α(OH)D3 and 1,500 IU cholecalciferol kg-1 of diet had significantly lower incidence and severity of TD in comparison with other groups. In conclusion, the results indicated that the supplementation of 1-α(OH)D3 in combination of 1,500 IU cholecalciferol kg-1 of diet could maximize tibia bone ash, performance and prevent TD in broilers fed TD inducing diet.

ABSTRACT. The effect of 1α-OH-D3 in calcium-phosphorus (Ca-P) deficient diets on Japanese quail growth performance and tibia parameters was investigated. Eight-day-old (n = 160) newly hatched quails were weighed and randomly allocated to 20 groups, each with 4 replicate pens of 8 birds. Treatments were as follows: T1, Ca-P-adequate; T2, Ca-P-deficient; T3, Ca-P-deficient + 500 FTU kg-1 of phytase (Ph); T4, Ca-P-deficient diet + 5 µg kg-1 of 1α-OH-D3; T5, Ca-P-deficient + Ph + 5 µg kg-1 of 1α-OH-D3. Results showed that quails fed Ca-P-adequate had significantly higher body weight compared with quails fed Ca-P-deficient, Ca-P deficient supplemented with 1α-OH-D3 and Ca-P-deficient supplemented with 1α-OH-D3 and phytase, but did not differ from Ca-P-deficient diet supplemented with phytase. Quails fed Ca-P deficient were unable to achieve FCR comparable to quails fed Ca-P-adequate (p < 0.05). The percentage of bone ash data indicated that quails fed Ca-P-adequate had higher tibia ash compared with other groups except for quails fed Ca-P deficient diet supplemented with combination of 1α-OH-D3 and phytase. Quails fed Ca-P-adequate had higher tibia P compared with quails fed Ca-P-deficient. In conclusion, these results indicated that quails fed Ca-P-deficient supplemented with 5 µg kg-1 of 1α-OH-D3 in combination of 500 FTU kg-1 of phytase were able to achieve the same tibia ash and Ca compared with quails fed Ca-P-adequate.