Result of Proficiency Test and Comparison of Accuracy Using a European Spine Phantom among the Three Bone Densitometries

Complexed amino acid minerals vs. bis-glycinate chelated minerals: Impact on the performance of old laying hens

The present study was to evaluate the effect of trace minerals (Zn, Mn, and Cu) from complexed amino acid minerals (ZMCAA) and bis-glycinate chelated minerals (ZMCGly) in laying hen diets on performance, internal and external egg quality, yolk mineral deposition, intestinal morphometry, and bone characteristics. From 78 to 98 weeks of age, 400 White LSL-Lite strain laying hens were distributed in a randomized design with 4 treatments with 10 replicates per treatment. Treatments were distributed in a 2 × 2 factorial arrangement using either Zn, Mn, and Cu of ZMCAA or ZMCGly source at 2 levels: low (20, 20, and 3.5 mg/kg of Zn, Mn, and Cu, respectively) or high (40, 40, and 7 mg/kg of Zn, Mn, and Cu, respectively). The analysis of variance was performed, and in cases where differences were observed, the means were compared using Tukey's test (P < 0.05). The source and level of trace mineral supplementation had a significant impact on the performance of laying hens. Hens fed ZMCAA had higher egg production (P = 0.01), egg weight (P = 0.02), egg mass (P = 0.01), and lower feed conversion ratio (P = 0.05) compared to those fed ZMCGly. The ZMCAA supplementation showed higher albumen height (P = 0.01), albumen weight (P = 0.01), and eggshell thickness (P < 0.01). The deposition of Zn (P < 0.01), Mn (P < 0.01), and Cu (P < 0.01) in the egg yolk was greater for hens received ZMCAA. Tibia weight (P = 0.04) and bone densitometry (P < 0.01) in the tibia were higher with ZMCAA supplementation. In the small intestine, ZMCAA resulted in longer villi (P = 0.02) and shorter crypt depth (P = 0.01) in the duodenum. Jejunum and ileum measurements were influenced by the level and source of trace minerals (P < 0.05). Laying hens fed ZMCAA exhibited superior performance, egg quality, deposition of trace minerals in the egg yolk, and bone density compared to hens fed ZMCGly. In this study, older laying hens supplemented with ZMCAA at lower levels demonstrated adequate levels of supplementation.

The Impact of Phytase and Different Levels of Supplemental Amino Acid Complexed Minerals in Diets of Older Laying Hens

A study was conducted to evaluate the effects of different sources and levels of supplemental amino acid-complexed minerals (AACM), with and without enzyme phytase (EZ). A total of 512 Dekalb White laying hens at 67 weeks of age were used in a 2 × 3 + 2 factorial arrangement of 8 treatments and 8 replications each. The main effects included EZ supplementation (600 FTU kg-1) and AACM inclusion level (100%, 70%, and 40% of inorganic mineral recommendations), plus two control treatments. The group of hens fed AACM-100 showed lower feed intake than the inorganic mineral (IM) group. The diet containing AACM-EZ-70 provided a higher (p < 0.05) laying percentage and a lower (p < 0.05) feed conversion ratio than both the IM and IM-EZ diets. The groups fed AACM-EZ-40, AACM-EZ-100, and AACM-70 produced heavier yolks (p < 0.05). Hens fed IM laid eggs with the lowest yolk and albumen weights (p < 0.05). Layers fed with AACM-100 and AACM-70 produced the most resistant eggshells to breakage (p < 0.05). In diets containing phytase, the optimal AACM recommendations for better performance and egg quality in older laying hens are: 42, 49, 5.6, 28, 0.175, and 0.70 mg kg-1 for Zn, Mn, Cu, Fe, Se, and I, respectively.

Accuracy, Linearity and Precision of Spine QCT vBMD Phantom Measurements for Different Brands of CT Scanner: A Multicentre Study

We describe a multicenter study using the European Spine Phantom (ESP) to compare the accuracy, linearity and precision of QCT measurements of spine vBMD between different brands of scanner, different models of the same brand and identical units of the same model. Ten scans of the same ESP with repositioning were performed on forty CT scanners from five manufacturers in different hospitals across China, all calibrated with the Mindways QCT system. The three ESP vertebral bodies simulating low (L1), medium (L2) and high (L3) vBMD and their average (L1-3 vBMD) were compared with phantom values. Linearity was assessed using the standard error of the estimate derived from linear regression. Precision errors were expressed as the standard deviation of the ten measurements on each scanner. Median (IQR) vBMD over all forty CT scanners compared with phantom values were: L1: 52.2 (49.9-56.4) vs 51.0; L2: 104.4 (101.2-108.6) vs 102.2; L3: 201.4 (195.0-204.9) vs 200.4; L1-3: 119.3 (116.6-123.2) vs 117.9 mg/cm³. Statistically significant differences in L1-3 vBMD were found between different brands (p= 0.005) and between different models of the same brand and identical units of the same model (both p< 0.001). Cross-calibration using linear regression gave a good fit for all forty systems with a median standard error of the estimate of 1.7 mg/cm³. The median precision error for L1-3 vBMD was 0.61 mg/cm³. Statistically significant differences in spine vBMD measurements between different scanners reinforce the importance of cross-calibration in multi-center studies. Cross-calibration can be reliably performed using linear regression equations.

Cross-Calibration of Bone Mineral Densities and Body Composition between GE Lunar Prodigy and Osteosys Primus

BACKGROUND

The aim of this study was to investigate the correlation between bone mineral density (BMD) and body composition measured by the Osteosys Primus® and the GE Lunar Prodigy® and to calculate the conversion rate between the 2 devices.

METHODS

The 40 subjects were men and women in aged 20 to 29 years old. All participants were scanned twice on both the Osteosys Primus (OsteoSys) and the GE Lunar Prodigy (GE Healthcare) DXA systems using the manufacturers' standard scanning and positioning protocols.

RESULTS

Compared to the GE Lunar device, the mean Osteosys fat mass was overestimated to be 12.1% (1,776.9 g) in the whole body, 5.1% (163.9 g) in gynoid, and 6.7% (87.2 g) in android. Compared with the GE Lunar device, the mean BMDs of the Osteosys Primus were underestimated to be 2.3% (0.023 g/cm2) in the whole body and 3.1% (0.035 g/cm2) in L1-4. Compared with the GE Lunar device, the mean lean mass derived by the Osteosys Primus were underestimated to 2.3% (1,045.3 g) in the total body, 3.8% (179.4 g) in arms, and 7.7% (1,104.8 g) in legs, respectively. There were a strong correlation of BMD and body composition between both groups.

CONCLUSIONS

Linear correction equations were developed to ensure comparability of BMD and muscle mass between the Osteosys Primus and the GE Lunar Prodigy. Importantly, use of equations from previous studies would have increased the discrepancy between the Osteosys Primus and the GE Lunar Prodigy.

Whole-body dual-energy X-ray absorptiometry demonstrates better reliability than segmental body composition analysis in college-aged students

Dual-energy X-ray absorptiometry (DXA) is rapidly becoming more accessible and popular as a technique to monitor body composition. The reliability of DXA has been examined extensively using a number of different methodological approaches. This study sets up to investigate the accuracy of measuring the parameters of body composition (BC) by means of the whole-body and the segmental DXA method analysis with the typical error of measurement (TEM) that allows for expressing the error in the units of measure. The research was implemented in a group of 63 participants, all of whom were university students. Thirty-eight males (22.6±2.9 years, average body mass 77.5±8.4 kg) and 25 females (21.4±2.0 years, average body mass 58.6±7.2 kg) were recruited. The measured parameters included body mass (BM), fat-free mass (FFM), body fat (BF), bone mineral content (BMC), bone mineral density (BMD). For the whole-body analysis, the determined TEM was: BM at the level of 0.12 kg in females and 0.29 kg in males; BF 0.25kg and 0.44% females, 0.52 kg and 0.66% males; FFM 0.24 kg females and 0.42 kg males; BMC 0.02 kg females and males; BMD 0.01g/cm2 females and males. The TEM values in the segmental analysis were: BF within the range of 0.04-0.28 kg and 0.68-1.20% in females, 0.10-0.36 kg and 0.72-1.94% in males; FFM 0.08-0.41 kg females and 0.17-0.86 males, BMC 0.00-0.02 kg females and 0.01-0.02 kg males in relation to the body segment (upper limb, trunk, lower limb). The BMD value was at the level of 0.01-0.02g/cm2. The study results showed high reliability in measuring body composition parameters using the DXA method. The whole-body analysis showed a higher accuracy of measurement than the segmental. Only the changes that are greater than the TEM, or the upper bound (95%) of the confidence interval of the measurement can be considered demonstrable when interpreting repeated measurements.

Bone mineral density in healthy Syrian women measured by dual energyX-ray absorptiometry

Assessment of bone mineral density (BMD) using dual energy X-ray absorptiometry (DXA) technique is considered as a standard technique for diagnosing osteopenia and osteoporosis and evaluating the severity of such diseases. Numerous studies have demonstrated the necessity to establish an ethnicspecific reference data for Bone mineral density measurements. Such data are lacking for the Syrian population. The objectives of this study are (1) to establish BMD reference values in a group of healthy Syrian women using DXA technique, (2) to compare with values from other populations, (3) to study the prevalence of osteopenia and osteoporosis in Syrian women using the manufacturer reference values. A total of 951 healthy Syrian women aged 20-79 years participated in this study. Weight, height, and BMI have been determined. BMD measurements were performed using Lunar Prodigy Advance System (GE). The data were compared with those from other populations. The results have demonstrated the expected decline in BMD with age after peaking at 30-39 years old group. The peak values of the lumbar spine and femur neck were 1.16 (0.12), and 0.95 (0.13) g/cm2, respectively. The results of the Syrian women were compared with those from other populations and the differences were presented. Osteopenia was diagnosed in 35.80% and 60.31% and osteoporosis in 6.23% and 2.72% in lumbar spine and femur neck, respectively, of women 50-59 years of age. These ratios increased to 36.84%, 68.42% and 23.68%, 13.10%, respectively, in the age group more than 59 years. BMD values of the Syrian women were determined for the first time. The results demonstrate the importance of establishing population-specific reference range for BMD values for an accurate assessment of Osteoporosis. High prevalence of osteopenia and osteoporosis was demonstrated in Syrian using the manufacturer reference values.

Measurement Uncertainty in Spine Bone Mineral Density by Dual Energy X-ray Absorptiometry

BACKGROUND

The purpose of this study was to calculate the measurement uncertainty of the process of bone mineral density (BMD) analysis using dual energy X-ray absorptiometry with traceability.

METHODS

Between March 2015 and October 2016, among healthy participants in their 20s and 30s, the study included those who had not taken calcium, vitamin D supplements and steroids and were without a history of osteoporosis, osteopenia and diseases related to osteoporosis. Relational expression of the model was established based on Guide to the Expression of Uncertainty in Measurements and Eurachem and the uncertainty from each factor was evaluated.

RESULTS

The combined standard uncertainty was 0.015, while the expanded uncertainty was 0.0298. The factor-specific standard uncertainties that occurred in the process of measuring BMD were 0.72% for the calibration curve, 0.9% for the internal quality control (IQC) using Aluminum Spine Phantom, 0.58% for European Spine Phantom (ESP), and 0.9% for the inspector precision (IP).

CONCLUSIONS

The combined standard uncertainty of the spine BMD corrected with ESP was 0.015 when measured at one time and targeting one participant. The uncertainties of the accuracy of the IQC and the IP were higher than that of the other factors. Therefore, there will be a need for establishment of protocols to lower these uncertainties.