Antoni Brodacki

Quality of Laying Hen Eggs During Storage Depending on Egg Weight and Type of Cage System (Conventional vs. Furnished Cages)

Abstract The aim of the study was to demonstrate the relationship of egg weight and egg quality traits with storage time and type of cages in which the laying hens were kept. The material consisted of 960 eggs from same age Hy-Line Brown hens kept in conventional and furnished cages at the same time in one building. The eggs were randomly collected, sorted by weight (S, M, L and XL), and stored under controlled temperature and humidity conditions. All eggs were weighed on days 1 (day of laying) and 28 of the experiment. During the same time they were candled to determine depth of the air cell, and 60 eggs from each subgroup were chosen to evaluate quality traits (egg weight and egg specific gravity), shell characteristics (shell strength, weight, thickness and density), and interior quality of eggs (albumen height and pH, yolk colour, weight and pH). The eggs (especially those from the heavier weight classes, XL and L) from hens reared in furnished cages were characterized by significantly smaller quality changes (egg weight loss, yolk proportion, albumen height, Haugh units) due to storage time in relation to those from hens kept in conventional cages. This fact could point to their better suitability for consumption. In addition to the housing system, changes occurring in eggs during storage should also be considered in terms of their weight class. Economically important egg traits (e.g. egg weight, shell strength) were better in eggs from furnished compared to conventional cages.

Slaughter traits and skin colour of newly crossed chicken broilers dedicated for extensive rearing system as a criterion of product identification and meat quality

Abstract The influence of genotype, rearing conditions (intensive vs. extensive) and fattening duration (9 vs. 12 weeks) on slaughter traits of chicken broilers including skin colour and meat quality were evaluated. The Cobb chickens with hybrids (C × GP or C × Sx) from mating cocks for fast-growing broilers production (C) and Greenlegged Patrigenous (GP) or Sussex (Sx) hens were compared. The evaluation of meat technological indices involved pH and electrical conductivity (EC), water-holding capacity, drip loss and cooking loss measurements. Shape and colour of carcasses skin allow to distinguish different genetic groups of chickens without optical instruments to constitute a marker allowing the identification of carcasses from extensively reared broilers. For slow-growing chickens, carcass traits such as better skin and meat colour saturation, more balanced and lower EC and pH were recorded. Variability of meat quality traits resulted from various genotypes, age and the interaction between the two factors.

The usefulness of different commercial strains of slaughter turkey females for extensive system of management and feeding

Abstract The aim of this study was to estimate the usefulness of turkey females derived from two commercial strains for the extensive system of feeding and management. The experiment included 100 female turkeys from each of two commercial lines, BUT9 and BIG6, which, after the 6th week of rearing, were randomly divided into two groups: the control (C) and the extensive (E), with five replications in each. In the 7th week of life, birds from the E groups were transferred to a building with an open access to runs. All birds were given balanced diets appropriate to their age. Birds from the E group were fed the balanced diets diluted with crushed wheat in various proportions and were additionally given green fodder and steamed potatoes. During the experiment, the production effects of birds: body weight gain, feed conversion ratio and survival rate were registered. Turkeys were slaughtered after 16 weeks of rearing. Before slaughter, blood samples were collected for haematological and serum biochemical indices determination. The European efficiency factor, protein conversion ratio and the mean cost of feeding were calculated. Significantly smaller body weight gains were observed in the heavier line in treatment E, suggesting the lighter birds may be more useful for the extensive rearing system. This fact could show better usefulness of middle heavy turkeys for the extensive rearing system. The influence of the rearing system on haematological parameters of turkey blood, demonstrated by a bigger number of red blood cells and the decrease of mean corpuscular volume in the blood of experimental birds, was stated. As well as the rearing conditions influenced level of aspartate, total protein and glucose; their level was higher, whereas the levels of lactate dehydrogenase, cholesterol, uric acid, phosphorous and iron were lower in the blood serum of birds from the E groups.