Temporal growth and development of body tissues of pigs as assessed by X-ray computed tomography
I. M. Barchia A , P. F. Arthur A C , L. R. Giles A B and G. J. Eamens AA Industry and Investment NSW, Elizabeth Macarthur Agricultural Institute, Menangle, NSW 2568, Australia.
B Present address: 26 Werombi Road, Camden, NSW 2570, Australia.
C Corresponding author. Email: paul.arthur@industry.nsw.gov.au
Animal Production Science 50(4) 322-328 https://doi.org/10.1071/AN10020
Submitted: 3 February 2010 Accepted: 15 April 2010 Published: 12 May 2010
Abstract
Data from 54 hybrid (mainly Large White × Landrace) pigs, comprising 18 male, 18 female and 18 castrated pigs, were used to quantify and mathematically describe the temporal growth and development of body tissues of live pigs. The pigs were 31.1 ± 3.6 kg liveweight (LW) and 70 ± 1 day of age (mean ± s.d.) at the start of the study, were individually penned, fed ad libitum and were weighed weekly. Computed tomography (CT) imaging was used to determine the weights of lean, fat and bone tissues of each pig at five different times during the study, which corresponded to ~30, 60, 90, 120 and 150 kg LW. The highest age and LW achieved by a pig were 31.4 weeks and 166.6 kg, respectively. A nonlinear mixed effects model of Gompertz function with sigmoidal behaviour was fitted to the data for each of the three sexes (male, female and castrate) to study the temporal growth and development of CT LW and the body tissues (lean, fat and bone). The estimate for CT LW at maturity was 237.5, 198.6 and 210.1 kg for males, females and castrates, respectively, and the corresponding prediction for the point of inflection (maximum growth rate) was 87.4, 73.1 and 77.3 kg. The predicted point of inflection for lean tissue was 47.0, 37.5 and 34.3 kg for males, females and castrates, respectively. In general, male pigs were the leanest, and castrates were the fattest, with females in between. Within sex, the ages at the point of inflection for lean tissue and bone tissue were lower than those for CT LW, whereas those for fat tissue were higher than those for CT LW. The percentage of bone tissue in the body generally remained stable with age (e.g. castrates had 9.2 and 9.0% at 14 and 26 weeks of age, respectively), whereas the percentage of lean tissue decreased with age (e.g. castrates had 61.3 and 50.4% at 14 and 26 weeks of age, respectively), and that of fat tissue increased with age (e.g. castrates had 16.8 and 25.8% at 14 and 26 weeks of age, respectively). Accurate mathematical models are required to develop management strategies to optimise pig production. The results of this study indicate that serial data on live pigs generated by CT imaging technology can be used to describe temporal growth and development of LW and body tissues of pigs using sigmoidal growth functions.
Acknowledgements
The authors acknowledge the financial support provided by Australian Pork Limited and PIC Australia Pty Ltd. The contributions of former staff of the Department of Industry and Investment NSW, P. J. Nicholls, K. J. James, L. J. Barker and D. Nicholson are gratefully appreciated.
Akridge JT,
Brorsen BW,
Whipker LD,
Forrest JC,
Kuel CH, Schinckel AP
(1992) Evaluation of alternative techniques to determine pork carcass value. Journal of Animal Science 70, 18–28.
|
CAS |
PubMed |
[Verified 20 November 2008]
Craig BA, Schinckel AP
(2001) Nonlinear mixed effects model for swine growth. The Professional Animal Scientist 17, 256–260.
[Verified 19 September 2008]
Suster D,
Luery BJ,
Ostrowska E,
Butler KL,
Kerton DJ,
Wark JD, Dunshea FR
(2003) Accuracy of dual energy X-ray absorptiometry (DXA), weight and P2 back fat to predict whole body and carcass composition in pigs within and across experiments. Livestock Production Science 84, 231–242.
| Crossref | GoogleScholarGoogle Scholar |
Suster D,
Leury BJ,
Kerton DJ,
Borg MR,
Butler KL, Dunshea FR
(2006) Longitudinal DXA measurements demonstrate lifetime differences in lean and fat tissue deposition in individually penned and group-penned boars and barrows. Australian Journal of Agricultural Research 57, 1009–1015.
| Crossref | GoogleScholarGoogle Scholar |
Szabo CC,
Babinszky L,
Verstegen MWA,
Vangen O,
Jansman AJM, Kanis E
(1999) The application of digital imaging techniques in the in vivo estimation of the body composition of pigs: a review. Livestock Production Science 60, 1–11.
| Crossref | GoogleScholarGoogle Scholar |
Verbyla AP,
Cullis BR,
Kenward MG, Welham SJ
(1999) The analysis of designed experiment and longitudinal data by using smoothing spline. Journal of the Royal Statistical Society, Series C 48, 269–311.
| Crossref | GoogleScholarGoogle Scholar |
Wagner JR,
Schinckel AP,
Chen W,
Forrest JC, Coe BL
(1999) Analysis of body composition changes of swine during growth and development. Journal of Animal Science 77, 1442–1466.
|
CAS |
PubMed |
Wellock IJ,
Emmans GC, Kyriazakis I
(2004) Describing and predicting potential growth in the pig. Animal Science 78, 379–388.
Whittemore CT,
Green DM,
Wood JD,
Fisher AV, Schofield CP
(2003) Physical and chemical composition of the carcass of three different types of pigs grown from 25 to 115 kg live weight. Animal Science 77, 235–245.
|
CAS |
