|Title||De invloed van D-vitamine en ultra-violette bestraling bij verschillende verhoudingen van Ca:P in het dieet|
|Source||University. Promotor(en): G. Grijns. - Wageningen : Veenman - 74|
|Publication type||Dissertation, internally prepared|
|Keyword(s)||zoötechniek - fysiologie - chemie - metabolisme - lichaamssamenstelling - biochemie - anabolisme - fosfor - vitamine d - arsenicum - chemische analyse - blootstelling - milieuafbraak - kinetica - ecotoxicologie - zootechny - physiology - chemistry - metabolism - body composition - biochemistry - anabolism - phosphorus - vitamin d - arsenic - chemical analysis - exposure - environmental degradation - kinetics - ecotoxicology|
|Categories||Animal Nutrition Physiology|
|Abstract||Two series of experiments with, respectively, 72(32♂ and 40♀) and 36 (all♀) spotted rats examined the influence of UV radiation and vitamin D on Ca and P metabolism. The experiments started at weaning of the rats (21-28 days) and lasted for 7 weeks in the first and for 5 weeks in the second series. Rations were used with Ca:P ratios varying between 1:045 and 1:2.8. Growth curves, skeletal X-ray photographs and Ca and P balances were studied.
Ca: P ratios between 1: 0.96 and 1: 1.27 proved optimum. Net absorption and retention of these minerals was maximum at that ratio. The rations with extreme Ca: P ratios induced rachitis that healed with both treatments. It was in these rations that net absorption of Ca reacted most sensitively to vitamin D or UV treatment. At all Ca: P ratios some reaction was observed with vitamin D and with UV-treatment. Excess of one of the two minerals inhibited the retention of the other. Inhibition by Ca was more potent than by P.