Effect of selenium and Ascaridia galli infection on antioxidant biomarkers in broiler chickens: a mathematical model for parasite reduction and host growth.

The activity of selenium-dependent glutathione peroxidase (GPX), liver concentration of vitamin E, and plasma and liver selenium levels were used for estimation of the antioxidant status of broiler chickens infected with Ascaridia galli. These biomarkers were recorded in an experiment covering 70 days p.i. At the same time the establishment rate of A. galli in chicken intestines, gain in the host body weight and chicken survival were studied. Broiler chickens (Cobb hybrids) were infected with 1450 embryonated A. galli eggs and treated with Sel-plex. A mathematical model was applied to determine the rate of nematode reduction and the relative rate of gain of host body weight, which are essential kinetic parameters of parasite-host interaction. The activity of GPX increased with both elevated selenium and reduced infection levels. The concentrations of selenium and vitamin E, and the GPX activity in the infected chickens demonstrated a similar pattern of change with time after day 30 p.i. The supplementation of the broilers with dietary selenium in the form of Sel-plex improved their antioxidant status. Increases by 29% in vitamin E concentration, 15% in GPX activity, and 22% in liver selenium concentration, respectively, were recorded in the infected and treated, compared to infected and untreated broilers.

Administration of Zn-Co-Mn basic salt to chickens with ascaridiosis. I. A mathematical model for Ascaridia galli populations and host growth with and without treatment.

A newly synthesized basic mixed salt (Zn(x)Co(y)Mn(1-x-y)) x (OH)6SO4 x 2H2O) was administered to chickens with ascaridiosis. Improvement in survival, gain in body weight (of 19.03%) and restoration of microelement content were observed in the treated chickens. An increase in the gain in body weight of 7.62% in uninfected treated chickens was also observed. The establishment of Ascaridia galli populations in chickens, and chicken growth in control and infected hosts, untreated and treated, were modelled mathematically. Some kinetic parameters (the rate of reduction of the nematode population nu and the relative rate mu of gain in body weight of the host) were determined. The values of nu =0.027 day(-1) and nu* =0.032 day(-1) were calculated for the reduction rates in infected, untreated chickens and in infected, treated chickens, respectively. The worm burden in infected, treated chickens was 20.4% lower than in infected, untreated chickens.

Administration of Zn-Co-Mn basic salt to chickens with ascaridiosis. II. Sex ratio and microelement levels in Ascaridia galli and in treated and untreated chickens.

Hisex chickens were infected with 1,450 embryonated Ascaridia galli eggs and treated with a new synthesized basic mixed salt (Zn(x)Co(y)Mn(1-x-y)) x (OH)6SO4 x 2H2O). The worm burden was determined and sex ratios for A. galli of M:F = 1.4 and M:F = 2 in untreated and treated chickens, respectively, were found. A decrease in the mean establishment rate of A. galli in treated chickens was observed. The levels of zinc, cobalt and manganese were determined in liver and muscle of the host and in male and female A. galli. The survival of the chickens and gain in body weight were improved, and the restoration of microelement content was observed by treatment with the salt. A positive effect of the basic Zn-Co-Mn salt was also observed in the nematode microelement levels. Significant differences were found between the levels of zinc, cobalt and manganese in male and female A. galli.

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(-), SO4(2-), 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 psi, alpha, micro and micros, values equal to those calculated in previously investigated A. galli-chicken systems. For parameter nu (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.

The effect of cobalt compounds on uninfected and Ascaridia galli-infected chickens: a kinetic model for Ascaridia galli populations and chicken growth.

The effect of dietary cobalt from three different sources on uninfected and Ascaridia galli-infected Hisex chickens, has been studied. The chicken diet was supplemented with 0.06 Co2+ kg-1 food either in the form of two glycine-cobalt compounds or mixed zinc-cobalt basic salt. An excess of dietary cobalt in small doses increases the gain of body weight and decreases host mortality. A greater bioefficiency of cobalt was established in infected chickens. A mathematical model has been used to provide a quantitative interpretation of the observed results. The model solutions of the kinetics of worm numbers and body weight are in a good agreement with experimental data. The model is valid for different degrees of A. galli infections and for treatment with different trace elements. The value of the kinetic parameter, regarded as a phenomenological constant of the host immune response, depends on the degree of infection.

Optimal treatment of Ascaridia galli-infected chickens with salts of trace elements and a kinetic model for chicken growth.

Data from seven experiments with Ascaridia galli-infected chickens have been considered. The results of treatment with neutral and basic copper, zinc and copper-zinc salts and inorganic and organic manganese compounds have been compared. An optimal therapy, containing a pure Cu basic salt (Cu2(OH)3Cl) and an organic Mn compound (2Gly.MnCl2.2H2O), is proposed to correct mineral deficiencies and pathological symptoms and to ensure lower mortality and higher gains in body weight. A mathematical model has been proposed for the growth of a healthy chicken. The relative rates for two growth stages have been determined by the model using data from mean chicken weights. The time course of the average biomass of a single A. galli has been theoretically derived from the same logistic equation describing chicken growth, which in turn might explain, phenomenologically, the mechanisms involved in the biomass growth of eukaryote organisms.

Trace element levels in the liver of rats with acute and chronic fascioliasis and after treatment with zinc-copper hydroxochloride mixed crystals.

Quantities of trace elements including copper, zinc, cobalt, manganese and iron were investigated in the liver tissue of rats at the acute or chronic stages of fascioliasis following treatment with zinc-copper hydroxochloride mixed crystals. Oral dosing (with food) of zinc-copper mixed crystals to healthy rats increased zinc and copper levels in the liver and decreased the iron content compared with controls. Manganese and cobalt levels did not change significantly. Significant reductions in all trace elements except manganese occurred in the liver of rats with acute or chronic fascioliasis. Manganese levels were slightly increased in rats at the acute stage and slightly decreased in rats at the chronic stage of fascioliasis. The application of mixed zinc-copper crystals at the acute or chronic stages of fascioliasis lead to a restoration of zinc and copper levels and a slight reduction in the iron levels in liver tissue of rats. The beneficial effects of applied salts were more apparent in rats chronically infected with Fasciola hepatica.

A kinetic model for Ascaridia galli populations in chickens treated with mixed salts of copper and zinc.

The action of mixed salts of copper and zinc (basic and neutral) on Hisex chickens experimentally infected with Ascaridia galli has been studied. The data show that the lowest host mortality and decrease in body weight gain and the highest reduction in nematode loading occurs in infected chickens treated with basic salts (in comparison with infected chickens, untreated or treated with neutral salts). A mathematical model has been proposed to provide a quantitative interpretation of the observed results. The model solutions of the kinetics of parasite numbers and of the gain in body weight are in a good agreement with the experimental data. One of the kinetic parameters in the model is defined as a phenomenological constant of the host immune response. Its value is determined in the case of infected and untreated chickens.

The effect of excess dietary manganese on uninfected and Ascaridia galli infected chicks.

The effect of dietary manganese from two different sources on chicks (uninfected and infected with Ascaridia galli) was studied. Chick diet was supplemented with 0.9 g Mn2+ kg-1 food either in the form of MnSO4.H2O or 2Gly. MnCl2.2H2O for 20 days. Chicks were divided into six groups: group 0, control; group 1, control + MnSO4.H2O; group 2, control + 2Gly.MnCl2.2H2O; group 3, infected with A. galli; group 4, infected with A. galli + MnSO4.H2O; and group 5, infected with A. galli + 2Gly.MnCl2.2H2O. Body weight, mortality, worn burden, and liver manganese content were investigated. Excess dietary manganese increased weights and manganese level, but mortality and worm burden were unaffected. A greater bioavailability of manganese from 2Gly.MnCl2.2H2O was established.

Content of some microelements in chickens with ascaridiasis under combined drug treatment.

The content of zinc, cobalt, and selenium in the intestinal wall of Leghorn chickens infected with Ascaridia galli was determined by nondestructive neutron-activation analysis. A comparison was made between the infected animals that were treated with Piperathrine and those that were given microelements or those that did not receive microelements. Age-dependent changes were found in the content of the microelements in the control groups. It is concluded that zinc, cobalt, and selenium are unevenly distributed in the intestinal tissues, with a dominating density of selenium occurring in the epithelial layer of the intestinal mucosa.

Application of small doses of copper salts (basic and neutral) to Ascaridia galli-infected chicks.

Male Hisex chicks were used in two experiments to investigate the interaction between Ascaridia galli infection and supplemental copper from basic and neutral salts. This was assessed by means of body weights, mortality, parasite burden and liver copper level. Cu2(OH)3Cl reduced the number of parasites but CuSO4.5H2O and CuCO3.Cu(OH)2.nH2O did not affect the parasite burden.

Kinetic model of parasite development and of the host microelement content under combined drug treatment.

The content of nine microelements has been investigated in a parasite-host system by nondestructive neutron activation analysis. A mathematical model has been proposed for the development of Ascaridia galli in the "Leghorn" chicks intestines and for the microelement content dynamics under combined treatment with antiparasite agent and microelements. An analytical solution of the system of nonlinear differential equations has been obtained for the case of simple invasion. The model explains well the experimentally observed process of the change in the microelement content. The recovery constant has been introduced for the damaged by the helminthosis tissue and its value has been determined.