Computer tomograph study of changes in the body composition of dual-purpose chicken genotypes between 4 and 12 weeks of age
The aim of this study was to compare the changes in the body composition of Tetra-H chicks, reciprocal crossbred progenies and chicks from a new cock line, which is planned to use as a new parental line in the breeding program of the TETRA-H. Altogether 90 chicks (15 in both sexes in all genotypes) were involved into the experiment and were scanned biweekly by means of a SIEMENS Somatom Emotion 6 multislice CT scanner between 4 and 12 weeks of age. During the scanning procedure a total of 20 scans were made of each animal, using 8 mm slice thickness and different distances between the scans, depending on the length of the vertebrae. Using this method, scans with the same serial number represent the body composition at the same anatomical points, and so animals of different sizes could be compared. Based on the results it was established that the highest liveweight was reached by the animals of the new cock line at the end of the experiment. However, the lowest ratio of the muscle and the highest ratio of the fat was also observed in these animals, which means an unfavourable body composition at the slaughter compared to the other two genotypes. Therefore, it was concluded that the use of the new cock line as new parental line in the breeding program of the TETRA-H seems to be good for increasing the liveweight of the TETRA-H chicks, but it could be unfavourable for the body composition.