Utilização de microalgas (Schizochytrium sp) como fonte rica em ácido graxo docosahexaenóico na dieta de poedeiras

Abstract

Low omega 3 PUFA consumption by population, for price (high fish price) or for cultural reasons, mainly in the eastern side of the world is a reality. Several studies have been conducted to enrich eggs in omega 3 PUFA to provide those nutrients to human population. Algae-derived omega 3, from Schizochytrium sp has been one of the alternatives to enrich eggs. Therefore, this study aimed to investigate the effect of a DHA-enriched algae product,on productive performance, immune status of layers, sensory evaluation and fatty acid profile of yolk eggs. A total of 192 30-week old Isa Brown layers allocated in cages (3 birds/cage), in a total of 16 replicates per treatment in a completely randomized design was used. During 126 days of experimental period, split into 6 productive cycles of 21 days each one of them, the birds received 4 dietary treatments: T1 – control (corn and soybean meal); T2: T1 + microalgae (0,5%); T3 –T1+ microalgae (1,0%) and T4 – T1+ microalgae (2,0%). Birds were vaccinated against Newcastle virus and underwent blood collection to evaluate total and differential leukocyte count. The fatty acid profile was obtained using gas chromatography and the sensory evaluation was analized using a multiple compaison test. Data were analized using variance and polinomial regression analysis. Productive performance, immune response, egg quality and sensory evaluation were not statistically influenced by dietary treatments. The yolk fatty acid profile was altered according to dietary treatments. An unexpected quadratic effect was observed for myristic acid, in which a higher level was attributed to yolks from hens that received 0,5% microalgae in the diets; increase in DHA omega 3 fatty acids and a decrease in the omega 6:omega 3 fatty acid ratio was observed as microalgae levels increased in the diets. These results indicate that the inclusion of microalgae in layer diets may increase yolk DHA content, without influencing egg quality, sensory evaluation, performance and immune response. Therefore, it may be considered a DHA-enriched egg for the population.