No abstract

SummaryEggs enriched with n-3 fatty acids and natural pigments are desirable in human food chain due to numerous benefits for health. In this study, we investigated the effects of inclusion of co-extruded linseed and sunflower meal into laying hens’ diet and replacement of synthesized pigment with paprika and marigold flower as sources of natural pigments. Four hundred 18–wk-old Bovan laying hens divided in two groups (control and experiment) were fed for 12 weeks. Fatty acids and β-carotene were monitored every fourth week and successively analyzed. Significantly (p<0.05) increased content of α-linolenic acid in egg yolk in the experimental group in comparison to the control group was observed with addition of linseed, paprika and marigold in laying hens’ nutrition. Nearly the same tendency was observed in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) content. Supplementation of the co-extruded linseed and sunflower meal into laying hens’ diet demonstrated significantly (p<0.05) lower n-6/n-3 FA ratio in experimental group compared to control group. The obtained results showed that the synthetic pigment added to laying hens’ diet provided better pigmentation of egg yolks after one and two months of the feeding trial than paprika and marigold flower. The concentration of β-carotene in egg yolks increased in experimental group after three months of the treatment, and that was the first time that concentrations of β-carotene did not significantly (p < 0.05) differ among control and experimental group, which shows that paprika and marigold flower as sources of natural pigments can successfully replace synthetic pigment. We shall continue research in this field with other supplemented mixtures, as there are indices for other potential feed enhancements among oily seeds and herbs.

Apple pomace (AP) is the main by-product of apple juice production. Large amounts of this material disposed into landfills can cause serious environmental problems. One of the solutions is to utilise AP as animal feed. The aim of this study was to investigate the impact of dried AP inclusion into model mixtures made from conventional feedstuffs on pellet quality and pellet press performance. Three model mixtures, with different ratios of maize, sunflower meal and AP, were pelleted. Response surface methodology (RSM) was applied when designing the experiment. The simultaneous and interactive effects of apple pomace share (APS) in the mixtures, die thickness (DT) of the pellet press and initial moisture content of the mixtures (M), on pellet quality and production parameters were investigated. Principal component analysis (PCA) and standard score (SS) analysis were applied for comprehensive analysis of the experimental data. The increase in APS led to an improvement of pellet quality parameters: pellet durability index (PDI), hardness (H) and proportion of fines in pellets. The increase in DT and M resulted in pellet quality improvement. The increase in DT and APS resulted in higher energy consumption of the pellet press. APS was the most influential variable for PDI and H calculation, while APS and DT were the most influential variables in the calculation of pellet press energy consumption. PCA showed that the first two principal components could be considered sufficient for data representation. In conclusion, addition of dried AP to feed model mixtures significantly improved the quality of the pellets.

Edible insects are acknowledged as a valuable nutritional source and promising alternative to traditional feed ingredients, while the optimization of rearing conditions is required for their wider utilization in the animal feed industry. The main goal of this study was to compare and optimize the rearing conditions of the two species’ larvae and identify the most favorable nutritive composition of the full-fat larval meal. For that purpose, Tenebrio molitor (TM) and Zophobas morio (ZM) were reared on three different substrates and harvested after three time periods. An artificial neural network (ANN) with multi-objective optimization (MOO) was used to investigate the influence between the observed parameters as well as to optimize and determine rearing conditions. The optimization of the larval rearing conditions showed that the best nutritive composition of full-fat larval meal was obtained for ZM larvae reared on a mixture of cabbage, carrot and flaxseed and harvested after 104 days. The best nutritive composition contained 39.52% protein, 32% crude fat, 44.01% essential amino acids, 65.21 mg/100 g Ca and 651.15 mg/100 g P with a favorable ratio of 1.5 of n6/n3 fatty acids. Additionally, the incorporation of flaxseed in the larval diet resulted in an increase in C18:3n3 content in all samples.