the objective of the study was to compare the effect of organic and conventional rearing systems on the productivity and meat quality of Yellowleg Partridge (Ż-33) and Rhode Island Red (R-11) chickens. a total of 492 sexed experimental birds (Gallus domesticus) were assigned to four groups. In groups I-C and III-C, the Ż-33 and R-11 chickens were reared under intensive conditions following conventional farming principles. In groups II-O and IV-O, the Ż-33 and R-11 chickens were kept according to organic farming principles. Body weight, feed conversion (kg/kg gain) and mortality were recorded throughout the study. On day 140 of rearing, the native breed chickens were subjected to simplified slaughter analysis, and meat pH, muscle colour, water holding capacity and chilling loss were determined. the meat samples were analysed for the chemical composition and profile of fatty acids, and the peroxidizability index (PI), thrombogenic index (TI) and atherogenicity index (AI) were calculated. The organically raised chickens were characterised by higher body weight (P≤0.01), better feed conversion (P≤0.01) and more favourable fatty acid profile of the muscles compared to the conventionally reared birds. Under organic conditions, the R-11 chickens showed better productivity but slightly poorer fatty acid profile of the muscles compared to the Ż-11 chickens.key words: chickens, native breeds, organic production system, performance, meat quality, fatty acid profile Organic farming is becoming increasingly popular in Europe and around the world. The main cause is the growing demand from consumers who are looking for safer and better controlled food products and who show concern for a healthy environment and animal welfare.

This study investigated the effect of adding extracts from selected herbs to water on alleviation of broiler stress associated with intensive production, and thus on improvement of welfare. In experimental groups (II, III and IV), alcoholic extracts from chamomile inflorescence (Matricaria chamomilla L.), lemon balm (Melissa officinalis L.) or from St John’s wort (Hypericum perforatum L.), respectively, were added to water drinkers (2 ml ∙ l-1 water) from 21 to 35 days of rearing for 5 h/day. Throughout the experiment, body weight, feed and water intake and number of dead birds were recorded once a week. At 21, 28, 35 and 42 days of rearing, blood was collected from 7 birds in each group to determine the levels of corticosterone, cholesterol, glucose, and the immunoglobulin complex. The response of birds to the herbal additives was positive. The herb extracts contributed to a decrease in cholesterol level and an increase in the level of the immunoglobulin complex in the blood. Supplementation of water with chamomile and St John’s wort extracts contributed to an increase in body weight, while the extracts from lemon balm and St John’s wort also had a positive effect on broiler survival. The results obtained indicate that out of the three herbs chosen for the experiment, St John’s wort extract proved the most efficient in relieving the body’s physiological response to stress, and thus in improving welfare.

The currently used poultry farming methods, which aim to maximise economic profit, are based on ever new technological solutions that improve flock management and increase bird performance. However, they do not always meet the natural needs of birds. Every housing method and technological solution currently in use is faced with some issues, such as social stress, adverse temperature/humidity conditions, risk of zoonoses, and behavioural pathologies, which determine poultry performance and welfare. Disregard for animal welfare involves not only ethical but also practical aspects, because well-being and housing comfort translate into better weight gains, health and productivity of the birds. The studies reported here suggest that every production system, despite the many welfare-improving aspects, causes numerous behavioural, productivity and health abnormalities in laying hens. Therefore, further research is needed to identify various risk factors for the purpose of improving housing systems and increasing the welfare of hens.

The aim of the present study was to determine the effects of supplementing drinking water with an extract of mixed herbs or housing with outdoor access on carcass traits, levels of antioxidant enzymes (SOD, CAT, GPx), reduced glutathione (GSH), malondialdehyde (MDA), and selected quality parameters of meat from broiler chickens. One-day-old Ross 308 broiler chickens were allocated to three groups: group I (control), in which birds were kept in compartments on litter and had no outdoor access; group II, in which birds were kept in compartments on litter without outdoor access and were supplemented with an extract of mixed herbs (50% Melissa officinalis L. and 50% Urtica dioica L.) at 2 ml/l of drinking water; and group III, in which birds were raised in compartments on litter and had outdoor access from day 1 of rearing. Throughout the rearing period, the broilers had free access to feed and water. On day 42, 20 birds were selected from each group, slaughtered and subjected to simplified slaughter analysis. Their breast and leg muscles were measured for pH, colour, water holding capacity (WHC) and drip loss, and analysed for the content of antioxidant enzymes (SOD, CAT, GPx), reduced glutathione (GSH), malondialdehyde (MDA) and fatty acids. The outdoor access reduced dressing percentage, both with (P≤0.01) and without giblets (P≤0.05). The supplementation of drinking water with the mixed herb extract (2 ml/l) improved the muscle antioxidant status (higher SOD, CAT and GSH content) and reduced lipid peroxidation in the leg muscles of the broilers (lower MDA level). In general, the supplementation of the diet with the mixture of herbs in the applied form and concentration, as well as the outdoor access had no effect on the other examined quality parameters of broiler meat.

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