Untersuchungen zur Körperzusammensetzung und zum Wachstum von Kälbern unterschiedlicher genetischer Herkunft mittels Dualenergie–Röntgenabsorptiometrie (DXA)

Abstract

Title of the paper: In vivo analysis of body composition and growth of calves of different genetic origin using dualenergy x-ray absorptiometry (DXA) In vivo body composition and growth of 214 calves (6-50 days old) of different genetic origin were analyzed using dual-energy x-ray absorptiometry (DXA). A whole body scan was performed. Looking at body composition there were differences among calf genotypes and parent genotypes. Purebred German-Holstein calves showed lower bone mineral density, bone mineral content, bone mineral percentage, fat tissue percentage and weight than the other genotypes. Opposite conditions existed for lean tissue percentage. Daily feed intake and tissue growth rates (lean tissue, fat tissue, bone mineral) were recorded from day 0 to day 50 of age. Further effects of birth type and lactation number of dam became obvious. Twins showed a significant higher daily gain than calves of single births. Heifer calves had highest daily gain between Scan 2 and Scan 3 in contrary to calves of cows of fourth or fifth lactation number. Within the study two scan modes were compared. A comparison between two scan modes 'normal' and 'pediatric large' showed a high correlation of selected values (r ≥ 0,90) except for lean tissue percentage (r = 0,62), fat tissue percentage (r = 0,70) and R-value (r = 0,69). In conclusion DXA is a very suitable method for examination of body composition and growth of calves.

Two-site evaluation of the relationship between in vivo and carcass dual energy X-ray absorptiometry (DXA) in pigs

“…Dual energy X-ray absorptiometry is becoming a more frequently used technology in farm animal research in order to study for example the in vivo changes in the body composition of pigs (Mitchell et al, 1996;Mitchell and Pursel, 2003;Suster et al, 2003), the carcass composition of sheep (Knott et al, 2003), or pigs (Mitchell et al, 1998;Marcoux et al, 2001;Scholz et al, 2002), the in vivo body composition of broilers (Buyse et al, 2003) or calves (Scholz et al, 2003;Hampe et al, 2005). A goal of live animal measurements is to predict carcass traits that are determinants of carcass value.…”