Investigations on skeletal development, bone mineralisation as well as calcium and phosphorus levels in blood of male fattening turkeys

Skeletal disorders are a frequent challenge in turkey production and are often attributed to nutritional influences with regard to calcium, phosphorus and vitamin D. Besides the dietary mineral content it is valuable to know the normal development of skeleton that accumulates highest amount of calcium and phosphorus. A fattening experiment, consisting of two trials (trial I/II: 3500/4320 male turkeys), was conducted (trial I: 2 genetically different lines housed in 4 groups; trial II: 5 genetically different lines housed in 30 groups). In both trials conventional diets were fed meeting the phase dependent nutrient requirements. The investigation was focused on the analyses of skeletal development including bone composition (ash, calcium, phosphorus) as well as histometrical and functional parameters and additional analyses based on blood parameters (calcium/phosphorus) in commercial toms during the whole fattening period (22 super(nd)weeks). At the end of both trials, the average weight of the randomly chosen animals of the lines ranged between 21.9 and 22.4 kg (trial I) and between 20.4 and 21.8 kg (trial II), respectively. The growth plates of the tibiotarsus (Tt) and the tarsometatarsus (Tmt) reached the largest dimensions in week 6 (