Background
Methods
Diets
Ingredients (%) | Normal | MgD | FGH | PGH |
---|---|---|---|---|
Casein | 20.0 | 20.0 | 15.0 | 15.0 |
Fish scale gelatin hydrolysate | 0.0 | 0.0 | 5.0 | 0.0 |
Porcine skin gelatin hydrolysate | 0.0 | 0.0 | 0.0 | 5.0 |
DL-methionine | 0.3 | 0.3 | 0.3 | 0.3 |
Corn starch | 15.0 | 15.0 | 15.0 | 15.0 |
Sucrose | 50.0 | 50.0 | 50.0 | 50.0 |
Corn oil | 5.0 | 5.0 | 5.0 | 5.0 |
Cellulose powder | 5.0 | 5.0 | 5.0 | 5.0 |
AIN-76 mineral premix | 3.5 | 0.0 | 0.0 | 0.0 |
AIN-76 mineral premix without magnesium | 0.0 | 3.5 | 3.5 | 3.5 |
AIN-76 vitamin mix | 1.0 | 1.0 | 1.0 | 1.0 |
Choline bitartrate | 0.2 | 0.2 | 0.2 | 0.2 |
Analysis values (mg/100 g) | ||||
Calcium | 533 | 530 | 524 | 521 |
Phosphorus | 553 | 563 | 519 | 519 |
Magnesium | 48 | 7 | 7 | 7 |
Animals
Bone parameters by X-ray CT analysis
Mechanical testing
Biochemical analysis
Statistics
Results
Growth parameters
Normal | MgD | FGH | PGH | |
---|---|---|---|---|
Food intake (g/d) | 15.9 ± 0.2 | 15.4 ± 0.4 | 15.4 ± 0.3 | 15.7 ± 0.3 |
Final body weight (g) | 292 ± 5a
| 268 ± 7b
| 277 ± 5a, b
| 277 ± 6a, b
|
Food efficiency (g/g) | 0.247 ± 0.005a
| 0.227 ± 0.002b
| 0.237 ± 0.003a, b
| 0.233 ± 0.002a, b
|
BMD and Ct.Th of the whole femur
Normal | MgD | FGH | PGH | |
---|---|---|---|---|
BMD (mg/cm3) | 656 ± 3a
| 629 ± 5b
| 649 ± 7a, b
| 633 ± 6b
|
Cortical BMD (mg/cm3) | 1058 ± 4a
| 1062 ± 4a, b
| 1073 ± 4b
| 1070 ± 2a, b
|
Trabecular BMD (mg/cm3) | 393 ± 3a
| 358 ± 5c
| 375 ± 4b
| 361 ± 5b, c
|
Ct.Th (μm) | 415 ± 2a
| 423 ± 4a, b
| 433 ± 6b
| 433 ± 4b
|
Mechanical testing
Normal | MgD | FGH | PGH | |
---|---|---|---|---|
Intrinsic biomechanical properties | ||||
Ultimate stress (MPa) | 141 ± 4 | 134 ± 6 | 129 ± 4 | 132 ± 1 |
Young’s modulus (MPa) | 1555 ± 68a
| 1250 ± 71b
| 1168 ± 66b
| 1138 ± 53b
|
Extrinsic biomechanical properties | ||||
Ultimate force (N) | 108 ± 3 | 115 ± 4 | 113 ± 3 | 122 ± 5 |
Ultimate displacement (mm) | 1.00 ± 0.02a
| 1.14 ± 0.03a, b
| 1.18 ± 0.05b
| 1.23 ± 0.06b
|
Work to failure (mJ) | 62.6 ± 3.0 | 66.3 ± 4.3 | 65.4 ± 2.1 | 76.2 ± 5.2 |
Stiffness (N/mm) | 81.4 ± 1.8 | 85.3 ± 2.6 | 80.4 ± 3.1 | 87.1 ± 1.9 |
Biochemical factors
Normal | MgD | FGH | PGH | |
---|---|---|---|---|
Mg (mg/dL) | 1.65 ± 0.05a
| 0.50 ± 0.02b
| 0.52 ± 0.06b
| 0.47 ± 0.03b
|
Total OC (ng/mL) | 273 ± 8 | 306 ± 19 | 303 ± 8 | 308 ± 8 |
ALP activity (units/μL) | 0.126 ± 0.007 | 0.113 ± 0.007 | 0.119 ± 0.004 | 0.110 ± 0.004 |
TRACP5b (U/L) | 11.3 ± 0.3 | 9.7 ± 0.8 | 10.7 ± 1.0 | 11.4 ± 1.1 |
CTX (ng/mL) | 37.3 ± 1.1 | 43.1 ± 3.6 | 37.3 ± 1.3 | 40.6 ± 1.6 |
CTX/TRACP5b ratio (% vs Normal) | 100 ± 4a
| 139 ± 12 b
| 109 ± 7 a, b
| 113 ± 10a, b
|