The fatty acid profile in the yolk and yolk sac from incubated goose eggs depends on the breeder age and laying period.

1. The study analysed the content of fatty acids in the lipids of the yolk and yolk sac of hatching eggs obtained from geese in four reproductive flocks and three laying periods at different incubation dates.2. A total of 1080 hatching eggs were used in the study (90 eggs from each age group in three laying periods). The geese were kept on one farm under the same conditions.3. On days 0, 16, 22, and 28 of incubation, the yolk/yolk sac was sampled. Saturated and unsaturated (mono- and poly-) fatty acids were determined, including myristic acid, palmitic acid, palmitoleic acid, margaric acid, stearic acid, oleic acid, linoleic acid, α-linolenic acid, behenic acid, eicosapentaenoic acid. The ratio of unsaturated to saturated fatty acids was calculated.4. Embryo fatty acid utilisation in eggs from different age groups of geese was similar. The fatty acid profile depended mostly on the laying period. The different proportions of fatty acids in the yolk during incubation indicated changes in the activity of various enzymatic processes in the membrane of the yolk sac of embryos from the beginning and at the end of the laying period.5. When analysing the interactions between the age of the parent flock and the laying period, the most significant effect on the fatty acid composition was found in fresh eggs. On d 16 of lay the myristic, stearic, linoleic, and behenic acids and PUFA; on d 22 of lay linolenic acid, and on day 28th palmitoleic and margaric acids were involved in this interaction.

Meat quality traits and fatty acid composition of breast muscles from ducks fed with yellow lupin.

The protein sources in feed have a huge impact on good-quality and -quantity meat traits. Yellow lupin (YL) seeds have a similar level of protein as soybean meal (SBM). The most popular is SBM that is genetically modified (GMO). During this age, the consumer market requires non-GMO products. Yellow lupin used as a high-protein substitute for SBM in feed has an effect on the quality of meat from broiler ducks. The aim of the study was to analyse and compare meat quality traits in breast and leg muscles as well as fatty acid (FA) composition in breast muscles from ducks fed mixtures containing YL as an alternative to SBM. Two hundred 1-day-old Cherry Valley ducks were kept in pens on litter in two equal dietary groups, four replications with 25 birds per group. The control group (1) received balanced feed containing SBM. The treatment group (2) received balanced feed containing YL. The feed provided to both groups contained 55% of concentrate and 45% of wheat. Birds received feed and water ad libitum and were reared for 8 weeks. After that, 16 ducks (eight from each group) of BW close to the mean for the whole group were slaughtered. Plucked and gutted carcasses were analysed in a laboratory for quality parameters. Meat was analysed for pH, colour, water-holding capacity and drip loss. Samples of breast muscles were analysed for the content of cholesterol, collagen, intramuscular fat and FA composition. The proposed feed mixture containing YL had no impact on meat traits, content of muscles or fat in duck carcasses (P > 0.05). The values of lightness (L*) and yellowness (b*) and collagen content in breast muscles were significantly higher (P < 0.05) in group 2 (YL). A lower ability to retain water, that is, higher water-holding capacity (percentage of water lost from meat) (P < 0.05), was found for leg muscles from group 2 (YL). The content of C16:0, C18:0, C20:4 n-6, C22:4 n-6, C22:5 n-3, total content of saturated fatty acids (SFA), values of atherogenic index and thrombogenic index were significantly lower (P < 0.05) in group 2 (YL) than in group 1 (SBM). The content of C18:2 n-6 and the polyunsaturated fatty acids-to-SFA ratio (P/S) were significantly higher (P < 0.05) in ducks fed the diet with the inclusion of YL. Diets with YL could be proposed as a partial substitute for SBM in duck-rearing.