Feeding Laying Hens Seal Blubber Oil: Effects on Egg Yolk Incorporation, Stereospecific Distribution of Omega-3 Fatty Acids, and Sensory Aspects

Abstract

Seventy-two 26-wk-old Single Comb White Leghorn laying hens were randomly assigned to 36 cages (2 per cage) in a 3-orthogonal 4 x 4 latin square, with the fourth row suppressed, to assess the effect of feeding refined seal blubber oil (SBO, containing 22.2% omega-3 fatty acids) on the fatty acid composition and position in the egg yolk lipids. The experiment was conducted over a period of 9 wk. Eggs were collected and numbered, and the weights were recorded for each week and cage. Eggs collected at wk 5 and 9 were used for total lipid, lipid class, fatty acid, and positional analyses. Sensory evaluation was carried out on eggs collected at wk 6 and 7. Feeding SBO at 1.25% led to an increase (P < 0.0001) in the long-chain omega-3 polyunsaturated fatty acids (LCn3PUFA) and a concomitant decrease (P < 0.0001) in arachidonic acid (ARA) in the egg yolk lipids. Yet this amount of SBO in the diet had no effect (P > 0.1) on the sensory attributes of the egg and on production parameters such as egg weight, number of eggs laid, and feed intake (P > 0.05). When feeding SBO in amounts higher than 1.25% proportionately, a plateau effect of the LCn3PUFA content of the eggs was observed. This appears to be because the PUFA content in the sn-2 position of the phospholipids cannot exceed a certain amount. When this amount is reached, the LCn3PUFA will be increasingly stored in triglycerides. The results presented here clearly indicate how eggs can be produced with optimized composition of LCn3PUFA without affecting (P > 0.1) the sensory properties of the eggs. The procedures elaborated herein provide directly applicable consequences for the food industry.

Ovarian follicular development, lipid peroxidation, antioxidative status and immune response in laying hens fed fish oil-supplemented diets to produce n-3-enriched eggs

“…However, Hargis (1988) suggested that egg yolk cholesterol showed little or no variation in response to genetic, pharmacological or dietary manipulation. Moreover, Schreiner et al (2004) did not find any differences in the yolk cholesterol content in response to dietary n-3 PUFA.…”

“…According to Schreiner et al (2004), egg production was not significantly affected because of including fish oil in commercial layer diets. However, Cortinas et al (2003) summarised that egg production was significantly higher when laying hens were fed diets containing 4% fish oil or flaxseed oil.…”

Quality characteristics of <i>n</i>-3 polyunsaturated fatty acid-enriched eggs

“…It is also important to point out that for general consumers of omega-3 products, small differences in colour, if detected, would be of secondary importance because colour is a minor important parameter in functional foods. The association between low sensory quality of eggs and dietary fi sh oils has long been recognized (Holdas and May, 1966): a negative effect on yolk aroma, taste and fl avour when laying hens were fed with a fi sh oil diet were reported recently by different authors (Gonzalez-Esquerra and Leeson, 2000;Schreiner et al, 2004;Carrillo-Domínguez et al, 2005). In some cases, a small percentage of panelists reported an unpleasant aroma and/or taste in the experimental diets, but this was also the case in the control diet, so these data are not conclusive.…”

“…Common dietary sources of omega-3 fatty acids include fi sh, crustaceans and mollusks, but there are other sources, such as linseed or marine microalgae. The use of these sources in laying hen diets in order to obtain enriched eggs may have negative effects, not only on hen health (Aymond et al, 1994;Van Elswysk et al, 1994;Bean and Lesson, 2003), but also on egg quality parameters and laying hen yields (Collins et al, 1997;Baucells et al, 2000;Gonzalez-Esquerra and Leeson, 2000;Schreiner et al, 2004).…”

Yolk Color and Lipid Oxidation of the Eggs of Commercial White Layers Fed Diets Supplemented with Vegetable Oils

“…Some of the fatty-acid sources added to layer diets are linseed oil (used for the production of ω-3 enriched oil), soybean oil and sunflower, which are used as sources of mono-and polyunsaturated fatty acids (Baucells et al, 2000;Schreiner et al, 2004).…”