Skip to main content
ARS Home » Research » Publications at this Location » Publication #63997
Title: INCREMENTAL CHANGES IN TOTAL AND REGIONAL BODY COMPOSITION OF GROWING PIGS MEASURED BY DUAL-ENERGY X-RAY ABSORPTIOMETRY

Author
item Mitchell, Alva
item Conway, Joan
item SCHOLZ, ARMIN - HUMBOLDT UNIVERSITY

Submitted to: Growth Development and Aging
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/21/1996
Publication Date: N/A
Citation: N/A

Interpretive Summary: In the past, the lack of accurate - non invasive methods has made it virtually impossible to monitor changes in body composition of an individual animal that occur during the period of growth and development. In this study and x-ray scanning technique, known as dual-energy x-ray absorptiometry or DXA, was investigated as a method for measuring changes in the fat, lean and bone mineral content of live pigs . Ten pigs were scanned at biweekly intervals as they grew from about 40 to 200 pounds. From this information it was possible to calculate the rates of fat, lean and bone mineral growth in the body. Furthermore, by defining specific regions of the body, it was possible to also calculate these rates of growth in the front legs, back legs and trunk of the body. The final DXA measurements of body composition were confirmed by slaughtering the pigs and performing chemical analysis of the carcasses. These results indicate that DXA could be and appropriate method for studies involving sequential measurements of body composition during growth.

Technical Abstract: The pig was used as a model for the application of dual-energy x-ray absorptiometry (DXA) for measuring changes in total and regional body composition that accompany body growth. Ten pigs were scanned at the beginning of the study (26.3.8.2 kg) and at 14 day intervals until reaching a final weight of 88.6.2.3 kg. Final body composition was validated by chemical analysis of the carcass. DXA fat and lean tissue measurements were corrected based on previous calibration studies. From individual growth curves, rates of fat (295.50 g/d), lean (531.50 g/d) and bone mineral (16.7.1.4 g/d) deposition rates were estimated. Furthermore, using regional analysis these tissue deposition rates partitioned into front legs, back legs and body trunk. The final DXA measurements of 87.5 kg for total tissue mass, 27.93 % for percent body fat and 24.4 kg for total fat mass were not significantly different (P<.05) from direct or chemical measurements. Also from the final DXA values for lean tissue mass it was predicted that the body contained 13.5 kg or 15.4% protein and 45.74 kg or 52.3% water. These results indicate that DXA could be and appropriate method for studies involving sequential measurements of body composition during growth.