Effects of dried Portulaca oleracea supplementation to the laying hen diet on productive performance, egg physical traits, fatty acid composition, and cholesterol content

Abstract

Portulaca oleracea is a widespread herbaceous plant particularly rich in polyunsaturated fatty acids (PUFA), antioxidant compounds and characterised by a healthy omega-6/omega-3 ratio. The focus of this research was to evaluate the effects of Portulaca oleracea supplementation to the diet of laying hens on productive performance, egg physical traits, fatty acid composition and cholesterol content. Twenty-six 24-week-old Warren strain layers were randomly assigned to two different groups of 18 and eight birds, respectively: one group received a commercial diet (C) whereas the other group was given the same control diet supplemented with 20% of dried Portulaca oleracea (PO). Hens were fed for 21 days. Feed and water were provided ad libitum. The poor palatability of the PO diet compromised the optimisation of the productive performance, with a significant reduction of the oviposition efficiency (0.69 vs 0.88 for PO and C, respectively; P < 0.05) and egg physical traits. Considering the egg nutritional traits, dietary PO significantly decreased the yolk proportion of saturated fatty acid (43.0% vs 44.1%, P < 0.05), while it increased the content of PUFA (19.4% vs 17.8%, P < 0.001), and within the latter, both omega-6 and omega-3 proportion significantly increased in comparison with C group (16.4% vs 17.6%, P < 0.001 and 1.46% vs 1.80%, P < 0.001, for n-6 and n-3, respectively). This resulted in an improvement of the omega-6/omega-3 ratio (10.4 vs 11.3 for PO and C, respectively; P < 0.05). Egg yolk cholesterol content did not vary between dietary treatments. It could be concluded that the use of Portulaca oleracea for producing omega-3-enriched eggs is feasible once the problem of palatability has been overcome and the energy requirements of the hens have been covered.