The aim of the study was to determine the effect of probiotics, prebiotics and synbiotics administered in ovo on selected morphological parameters of the small intestine (duodenum, jejunum, ileum) in broiler chickens (Ross 308) and native chickens (Green-legged Partridge, GP). On the 12th day of embryonic development (the incubation period), an aqueous solution of a suitable bioactive substance was supplied in ovo to the egg’s air cell: probiotic—Lactococcus lactis subsp. cremoris (PRO), prebiotic—GOS, galacto-oligosaccharides (PRE) or symbiotic—GOS + Lactococcus lactis subsp. cremoris (SYN). Sterile saline was injected into control (CON) eggs. After hatching, the chicks were placed in pens (8 birds/pen, 4 replicates/group) and housed for 42 days. On the last day of the experiment, all birds were individually weighed and slaughtered. Samples for histological analysis were taken directly after slaughter from three sections of the small intestine. In samples from the duodenum, jejunum and ileum, the height and width of the intestinal villi (VH) were measured and their area (VA) was calculated, the depth of the intestinal crypts (CD) was determined, the thickness of the muscularis was measured and the ratio of the villus height to the crypt depth (V/C) was calculated. On the basis of the obtained data, it can be concluded that the applied substances administered in ovo affect the production parameters and intestinal morphology in broiler chickens and GP. The experiment showed a beneficial effect of in ovo stimulation with a prebiotic on the final body weight of Ross 308 compared to CON, while the effect of the administered substances on the intestinal microstructure is not unequivocal. In GP, the best effect in terms of villi height and V/C ratio was found in the in ovo synbiotic group. Taking into account the obtained results, it can be concluded that chickens of different genotypes react differently to a given substance; therefore, the substances should be adapted to the genotype.

The aim of the research was to determine lipid metabolism indices and fatty acid profile in the blood serum of Ross 308 chickens (n = 48), fed a finisher mixture supplemented with 0, 0.25, 0.5 and 1.0% of lignocellulose. The feeding trial lasted from 21 to 42 d of the birds' age. Blood samples were collected from each chicken at 42d of age from the pterygoid canal vein. In the blood serum the content of triglycerides (TG), total cholesterol (TCHOL) and high density lipoprotein (HDL) fraction was determined by the spectrophotometric method. The fatty acids concentration was estimated with the use of the gas chromatography method. Lignocellulose in doses of 0.5 and 1.0% significantly reduced the concentration of triglycerides and low density lipoprotein (LDL) fraction. Saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) content was not affected by dietary treatments whereas lignocellulose significantly influenced the profile of polyunsaturated fatty acids (PUFA) from n-3 and n-6 families. Insoluble fiber decreased (p< 0.05) serum concentration of a-linolenic acid (C18:3n-3) and increased share of docosahexaenoic acid (C22:6n-3), dihomogammalinolenic acid (C20:3n-6) and arachidonic acid (C20:4n-6) in total PUFA, compared to the control birds. The results of the present study have shown that the incorporation of limited amounts of lignocellulose into the broiler diet can influence the lipid metabolism in the chickens.

The aim of the study was to determine the changes in the content of major proteins, glucose and selected hormones in the blood of piglets during the first 7 days of neonatal life. The study involved an entire litter of eight newborn piglets of F1 hybrids (Polish White Large x Polish Landrace) delivered from one sow in the second gestation. In blood samples collected directly after parturition (before colostrum intake), in the 12^th, 24^th and 48^th hour and in 7^th day of life, the content of total protein and its fractions, glucose concentration and the level of insulin, T₃ (total and free), T₄ (total and free), leptin, resistin and ghrelin (total and active) was determined. In the blood serum of newborn piglets a low content of total protein, albumins, gamma globulins and a high share of alpha- and beta globulins was found. In the 12^th hour of life, after colostrum intake, a significant (P<0.05) increase in the content of total protein, albumins, beta-globulins and a rapid increase of gamma globulins as well as decrease of alpha-globulins level were observed. In the consecutive periods of postnatal life a significant (P<0.05) decrease of total protein, beta- and gamma globulins as well as a steady increase in the content of albumins in the blood serum of piglets was observed. The content of glucose, insulin, leptin, resistin and ghrelin in the blood serum of neonates increased significantly (P<0.05) after colostrum intake. During the successive experimental periods a progressive increase (P<0.05) of glucose and T₃ as well as systematic decrease of insulin, T₄, ghrelin and resistin in the blood serum was observed as compared to the 12^th hour of life.

The aim of the research was to determine the concentration of total protein and its fractions as well as the concentration of selected mineral components in the blood serum of male broiler chickens Cobb 500 fed diets with different cellulose content. Blood samples were collected for examination from the birds' pterygoid canal veins on their 42 day of age. There was no influence of cellulose preparation on the content of total protein and its fractions: albumins, alfa₁-, alfa₂-, beta-, gamma-globulins, albumin to globulin ratio, inorganic phosphorus, sodium, potassium, chloride and iron concentrations in blood serum. The highest calcium concentration (P<0.05) was detected in the blood serum of males fed a diet with the highest cellulose content (0.75-0.95%). Simultaneously, a tendency of increased calcium content was observed along with an increased amount of pure cellulose in diets. The lowest magnesium level (P<0.05) was observed in the blood of birds fed diets with the lowest amount of cellulose (0.25-0.45%). The magnesium level in the blood of birds fed a diet with higher amounts of cellulose did not considerably differ from the control group. Results from the current study suggest that introduction of a limited amount of pure cellulose into the diet of broiler chickens does not affect total protein concentration and protein fractions but can influence the mineral content in the blood serum.