the aim of the study was to evaluate the quality of eggs from hybrids of laying hens of selected Polish breeding strains depending on their housing system. analysis was made of eggs from Ka-62, Ka-42, Ka-68 and Ka-48 hybrids housed in three systems: cage, litter and free range. one hundred eggs, randomly chosen from each experimental group between 34 and 36 weeks of age, were evaluated for a set of physical characteristics such as weight of egg and egg fraction, percentage of main egg fractions, egg shape index, air cell height, albumen height and ph, haugh units, yolk colour and ph, as well as shell colour, thickness, density and deformation. caged birds produced the heaviest eggs (61.06 g) with the lowest shape index (77.86%), lightest shell (39.86) and highest percentage of albumen (57.04%) and yolk (29.89%) in the egg. the most favourable quality traits of albumen from the analysed eggs, i.e. greatest height (5.00 mm) and haugh units (69.70) were characteristic of egg albumen from hens raised on litter. shell quality analysis showed that the eggs of free-range birds were characterized by the highest weight of shell (5.76 g), which had the greatest thickness (360.14 µm) and density (81.01 mg/cm 2 ). Detailed analysis of the physical characteristics of eggs from the hybrids of laying hens revealed significant (P≤0.05) differences depending on the housing system. the eggs of caged layers showed many characteristics desired by processors. meanwhile, the eggs of hens kept on litter were characterized by dietetic properties that could meet specific needs of the consumers.

The aim of the study was to characterize the sensory quality and physical traits of raw and heattreated meat depending on the origin, sex and feeding of geese. The experiment used meat from domestic geese of southern varieties: lubelska (lu), kielecka (ki) and subcarpatian (sb), included in the conservation programme. The experiment was carried out on a total of 192 birds divided according to origin (lu, ki and sb), sex (m and f) and dietary treatment (di -conventional feeding and dii -oat fattening). To evaluate the quality characteristics of meat, 16 birds from each group were selected. sensory evaluation of raw goose muscles was at a good level of consumer acceptability and exceeded 4.0 points, ranging from 4.18 pts (appearance/ki) to 4.59 pts (aroma/sb) for breast muscles (Bm), and from 4.17 pts (fatness/lu) to 4.53 pts (aroma/sb) for leg muscles (lm). in the case of heat-treated muscles the tenderness of the muscles of lu geese was characterized by high number grade (P≤0.05) for both the BM (4.87 pts) and LM (4.76 pts). Lighter colour (L*) (P≤0.05) was characteristic of the muscles of oat-fattened birds (44.25 for BM and 49.86 for LM) compared to the muscles of conventionally fed birds (39.77 for Bm and 46.89 for lm). in addition, a significant (P≤0.05) effect of diet was also found on the value of the parameter a* (redness) and b* (yellowness). Parameter a* ranged from 10.45 (lu) to 11.96 (ki) for Bm and from 13.28 (Ki) to 14.21 (Sb) for LM. In turn, the highest share (P≤0.05) of yellow colour (parameter b*) was demonstrated in the muscles of ki geese -4.87 for Bm and 10.92 for lm. male muscles were characterized by higher (26.34 mg% -Bm and 24.37 mg% -lm) water holding capacity (Whc) than female muscles (27.23 mg% for Bm and 25.28 mg% for lm respectively). furthermore for Bm of oat-fattened geese cooking loss was at the level of 10.50%. The present study indicated that most of the sensory characteristics of meat (Bm and lm) from geese of different breeds were affected (significantly at P≤0.05) by the diet. This concerned both raw and heat-treated meat. For raw breast muscles, a significant (P≤0.05) effect of sex was also found (with the exception of aroma). In turn, the quality characteristics of raw leg muscles (except for colour) were influenced (P≤0.05) by all the treatment factors. analysis of the physical properties of meat showed that these parameters are mainly affected (P≤0.05) by the diet. key words: goose, genotype, diet, meat, sensory analysis, physical properties * Work financed from statutory activity, project no. 03-014.2.

Due to the planned limitations in the use of genetically modified soybean meal, the search for alternative sources of protein in animal nutrition is ongoing, which also supports the consumers’ expectations of good quality products, such as eggs. The aim of the study was to assess and compare morphological traits of eggs, fatty acid composition in yolk lipids, and the content and activity of lysozyme in thick and thin albumen in eggs from hens fed a diet based on legume seeds as a substitute for soybean meal depending on the hens age. Analyses were carried out for 300 eggs on dates I–V (19–39 weeks age of hens), obtained from Rosa 1 hens managed in the semi-intensive system. Quality analysis was performed for 30 eggs from each group at a time. The control group of hens (A) was fed a diet based on soybean meal (SBM) and the treatment group (B) was fed a diet based on seeds from narrow-leaved lupin (Boruta), yellow lupin (Mister), and pea (Muza). Eggs were analysed for morphological traits (egg weight, the weight and density of egg components, egg shape index and egg surface area), parameters of albumen (height, Haugh units), yolk colour (La Roche, colorimetry in the CIE Lab system), lysozyme content and activity in albumen, and fatty acids composition in yolk lipids. In group B the egg shape index was higher (p = 0.002), and the eggshell colour index was lower (p = 0.007), as well as the height of thick albumen, Haugh score, and yolk colour (La Roche) were higher in group B (p < 0.05), while redness of yolk was significantly lower (p < 0.001) than in group A. Lower content of C15:0 and C18:1n9 and higher content of C18:2n6 and C18:3n3, (p < 0.05), as well as lower content of MUFA and OMEGA 9, but higher content of PUFA, OMEGA 3, OMEGA 6, PUFA/SFA, OMEGA 9/6 and OMEGA 9/3 were found in group B compared to group A (p < 0.05). There were significant differences in traits between age of hens (p < 0.05). Egg weight, yolk weight and its proportion in egg, as well as shell weight, its strength and thickness increased with the age of hens (p < 0.05). The content of lysozyme and its activity were also higher in eggs from older hens (p < 0.05). Fatty acids composition was beneficial at the beginning and end of the analysed egg production period. The proposed feed mixture based on legume seeds had no negative effect on the quality of eggs, and had a positive effect on yolk colour, the quality of albumen. There was no detrimental effect of diet and age of hens on fatty acid composition of eggs from both groups throughout the study period. To sum up, diet with legume seeds could be accepted as a substitute for soybean meal, due to the beneficial effects for some mentioned traits of eggs. Use of legumes could give a partial self-sufficient for producers from small farms, where is not possible to produce soybean meal. At the same time, the level of anti-nutrients in legumes should be considered.

The aim of the study was to determine shell quality of eggs laid by some strains of native breed hens of different ages, with special consideration of their effect on lysozyme concentration and enzymatic activity. Evaluation was made of the eggshells from 6 breeds/strains of laying hens covered by the gene pool protection program in Poland: Greenleg Partridge (Z-11), Yellowleg Partridge (Ż-33), Rhode Island Red (R-11), Rhode Island White (A-33), Sussex (S-66), and Leghorn (H-22). Significant ( P ≤ 0.01) differences were established for all the shell quality characteristics between hen strains. As the birds aged, shell weight and porosity increased, and shell compression strength decreased in all the experimental groups. Lysozyme content was lowest in white-shelled eggs (H-22) and highest in cream-colored and light brown eggs (Z-11, Ż-33, and R-11). Furthermore, age of hens had a greater effect on lysozyme concentration and activity in the eggs than on shell quality traits. Regardless of the layer genotype, eggs from older hens showed higher lysozyme concentration and enzymatic activity.

The objective of the study was to evaluate the quality of eggs laid by native breed hens of different ages (33 and 53 weeks of age), with particular consideration of the lysozyme parameters. Eggs were collected from 6 breeds/strains of laying hens under the genetic resources conservation in Poland, i.e. Greenleg Partridge (Z-11), Yellowleg Partridge (Ż-33), Rhode Island Red (R-11), Rhode Island White (A-33), Sussex (S-66) and Leghorn (H-22). The yolks of eggs from older hens had a more favourable, intense colour, but the freshness parameters (albumen height and Haugh units) of these eggs were lower. The albumen of eggs from older hens showed greater content and higher enzymatic activity of lysozyme in both thin and thick albumen. Among the six strains of hens, lysozyme content and enzymatic activity were highest in the egg albumen of strains Ż-33, Z-11 and R-11, and lowest in that of strain H-22. The analysed eggs showed statistically significant correlations between some interior egg quality traits (albumen weight, albumen height, Haugh units, yolk colour) and the discussed enzyme parameters. These traits are influenced by genotype and age of the hens.