Effects of glycine–metal compounds on Ascaridia galli-infected chickens expressed by a kinetic model

The biogenic elements zinc, manganese and cobalt are essential for metabolic processes in animals. Compounds of nGly.Me2+A. mH2O (Me2+=Zn2+, Mn2+, Co2+; A=Cl−, SO42−, n=1, 2; m=2, 5), as supplements in the diet, were used separately on different experimental groups of male Hisex chickens to correct the mineral deficiency caused by Ascaridia galli infections. An amelioration of body weight gain, reduction of mortality and restoration of trace element levels were estimated in infected chickens. A mathematical model has been proposed for A. galli population kinetics in chickens, taking into account the stimulating effect of these elements on the nematodes. The model parameters are considered as phenomenological constants of the host–parasite system. An agreement with experimental data is observed using, for the parameters ψ, α, μ and μs, values equal to those calculated in previously investigated A. galli–chicken systems. For parameter ν (immunological constant) the same value was obtained as in a previous experiment with high infection. This model is likely to be suitable for a range of host–nematode systems, including varying degrees of infection and treatment with different trace elements.