Body composition and development measured repeatedly by computer tomography during growth in two types of turkeys

Department of Animal Science, Agricultural University of Norway, As-NLH. ulrik.brenoe@ihf.nlh.no

Distribution and development of fat, muscles, and bone were studied repeatedly by computer tomography from 4 to 17 wk of age in two commercial strains of turkeys (BUT-9 and Nicholas) of both sexes. Generally, the proportion of total fat and meat increased and bone decreased significantly throughout the experimental period for both strains and sexes. When compared at the same age or body weight, BUT-9 tended to have a higher percentage of meat than did Nicholas (0 to 3 percentage units). From 8 to 17 wk of age, Nicholas showed higher fat percentage and lower bone percentage than BUT-9. Based on this study, regardless of weight at slaughtering, BUT-9 should be preferred. Because males had a significantly higher body weight gain and higher percentage of meat from 8 wk of age, males should be used in production to fit the market for high slaughter weights with large pieces of meat. Because females had a higher meat percentage at young ages compared with males, but showed an earlier fattening and lower weight gain, females should preferably be slaughtered at lower live weights. Computer tomography can be considered an appropriate but expensive method to study body composition and development in turkeys.