Submitted to: Archives of Animal Breeding
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/5/2011
Publication Date: 1/1/2012
Citation: Mitchell, A.D., Ramsay, T.G., Scholz, A.M. 2012. Measurement of changes in body composition of piglets from birth to 4 kg using quantitative magnetic resonance (QMR). Archives of Animal Breeding. 55:64-71. Interpretive Summary: During studies of the growth of neonatal piglets it is important to be able to accurately assess changes in body composition. Body composition analysis results can be used to monitor and evaluate growth patterns, genetic improvement, dietary treatments, progression of chronic disease, and efficacy of medical interventions. Quantitative magnetic resonance (QMR) provides accurate measurements of total body fat, lean, and water in non-anesthetized piglets. This study demonstrates that QMR is a useful method for measuring changes in body composition in neonatal pigs. A major advantage of using the QMR for the body composition measurements is that, in addition to its accuracy, the procedure results in minimal stress to the pigs, thus permitting frequent serial measurements without interfering with the growth of the pigs.
Technical Abstract: The purpose of this study was to use quantitative magnetic resonance (QMR) to measure changes in the body composition of piglets during growth from birth to 4 kg BW. Using QMR, 60 pigs were scanned an average of 5 times starting at 2.7±1.3 d of age (1.95 kg) and finally at 13.1±4.3 d (4.14 kg). Regression analysis revealed that the rates of total body growth and fat and lean deposition were linear throughout this period. Subsequently, a 2nd group of 235 pigs (109 males and 126 females) were scanned twice, first at 2.7±1.2 d of age and then at 13.4±3.1 d of age. The mean (±SD) rate of total body growth was 230±57 g/d. The rates of fat and lean deposition were 40±13g/d and 191±52g/d, respectively. The rates of both fat and lean deposition were highly correlated (P<0.001) with total body growth rate (R2 = 0.81 and 0.93, respectively) and the coefficient of determination between the rates of fat and lean deposition was 0.71 (P<0.001). The results of this study demonstrate that QMR is a useful method for measuring changes in body composition in neonatal pigs. Furthermore, the results indicate that during the period of growth from birth to 4 kg, the rates of both fat and lean deposition are linear and highly correlated with total body growth.