Paradigm shift in poultry feeding: the development of omega 3 enriched eggs

The objective of this study was to determine the enrichment levels of chicken eggs with the inclusion of varying levels of flaxseed oil in layer diet. As part this study, a preliminary trial was conducted to assess the potential of an indigenous seed in Ghana as a source of omega-3 polyunsaturated fatty acids. Oils from egusi (melon seeds) and werewere (neri seeds) seeds were extracted and omega-3 and omega-6 content evaluated using the Gas Chromatography technique. Following the results, 80 commercial Lohmann tradition layers (n=20 per treatment) were randomly allotted to 4 dietary treatments with varying levels of flaxseed oil (control (0%), 1.5%, 3% and 4.5%) from 39 weeks of age of layers until 70 weeks. Individual omega-3 and omega-6-fatty acids were extracted from the egg yolk beginning 41 to 70 weeks and analysed using Gas Chromatography technique. Egg quality was also determined as the level of flaxseed oil increased in the diet in addition to storage duration of eggs over a period of 14 days. At 70 weeks of production, 5 birds from each treatment were randomly selected, euthanized by cervical dislocation and dissected for evidence of fatty liver haemorrhage syndrome. The data was analysed using the SAS Proc. GLM procedure and ls means separated by the PDIFF procedure of SAS at P<0.05. The results showed that both egusi and werewere contained 61.18% and 54.03% linoleic acid (an omega-6 fatty acid) respectively but both had no trace of omega 3 fatty acids. By substituting feed ingredients such as maize, soyabean meal and fishmeal in layer diet with 3% flaxseed oil, there was about 0.2 mg/ml deposition of omega-3 and omega-6 fatty acids deposited chicken eggs. The level of deposition of omega 3 (n;3 PUFA) and omega 6 (n;6 PUFA) in the 3% inclusion of flaxseed oil was 2.58 fold higher than the control which had no flaxseed oil. For individual n-3 PUFA levels, the fold increases from control diet to the 3% oil inclusion were: 18:3 n-3 (α-linolenic acid, (ALA) = 1.55; 20:3 n-3 (Eicosatrienoic acid, (ETA) = 16.79; 20:5 n-3 (Eicosapentaenoic acid, (EPA) = 0.15; 22:3 n-3 (Docosatrienoic acid) = 27.81; 22:5 n-3 (Docosapentaenoic acid, (DPA) = 1.6; and 22:6 n-3 vi (Docosahexaenoic acid, (DHA) = 3.22. Haugh unit value, which is a measure of protein quality in the albumen of eggs was 81.2 in the 3% flaxseed oil group compared to the rest of the treatment (Control (81.0), 1.5 (79.9) and 4.5 (80.8). The treatment with 4.5% flaxseed oil had heavier (P <0.05) egg weight of 63.81g compared to the rest (Control (61.3g), 1.5 (61.7g) and 3 (60.7g). When eggs were stored over a period of 14 days in ambient temperature there was strong reduction in albumen quality (y = -2.3444x + 97.15, R² = 0.96) with increasing days of egg storage, an indication of increasing loss of carbon dioxide and moisture from the eggs. There was little effect (P>0.05), of feeding treatments on egg quality. There was no difference (P>0.05) in live weight of birds, liver weight and abdominal fat weight between the treatments. The treatments with 3% and 4.5% flaxseed oil had higher (P<0.05) liver haemorrhage score compared to 1.5% flaxseed oil inclusion and control. This could mean continuously feeding of birds on high amount of the oil diets and PUFA impact the health of the birds negatively. However, there were no mortalities associated with the haemorrhage score. Therefore, further studies should examine the optimum interval to ensure proper egg enrichment without jeopardizing the health of the birds.

Source: KNUST