Enriching the egg yolk in n − 3 fatty acids by feeding hens with diets containing horse fat produced in Uruguay

• Published in: Food chemistry 2006, Vol.98 (4), p.767-773
• Main Authors: Cabrera, M.C., Saadoun, A., Grompone, A., Pagano, T., Salhi, M., Olivero, R., del Puerto, M.
• Format: Article
• Language: English
• Subjects: animal fats and oils; Biological and medical sciences; DHA; docosahexaenoic acid; Egg and egg product industries; egg shell thickness; egg weight; egg yolk; Eggs; Fatty acids; feed rations; feed supplements; Feeding. Feeding behavior; food composition; Food industries; Fundamental and applied biological sciences. Psychology; heat treatment; hen feeding; Horse fat; horse meat; laying hens; linoleic acid; linolenic acid; lipid content; n − 6/ n − 3 ratio; nutritive value; pressed fat; rice oil; saturated fatty acids; sunflower oil; tallow; Vertebrates: anatomy and physiology, studies on body, several organs or systems
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2005.07.013

The present study was conducted to evaluate the ability of horse fat produced in Uruguay, compared with other lipid sources supplemented in the diet of laying hens, to modify the lipid composition and the n − 6/ n − 3 fatty acid ratio of the produced eggs. For this purpose, 60 laying hens ( Gallus domesticus) were fed for 30 days with five experimental diets (12 hens/diet) containing 3% sunflower oil (SO), rice oil (RO), beef tallow (BT), pressed-fat (PF), obtained by pressing fat from bovine viscera, and horse fat (HF) obtained from horse bone medulla. Throughout the trial, feeding rate, shell index, weight and total lipid contents of eggs, were not affected by the different diets. Feeding on the SO and RO diets significantly increased the amount of linoleic acid of the egg, although it was lower in the RO than in the SO eggs. Diet BT did not affect the saturated fatty acid content of the yolks. The diets with animal fats containing 18:3 n − 3 (diets PF and HF), resulted in a significant increase in the n − 3 fatty acid contents of the eggs, through an increase of linolenic (18:3 n − 3) and docosahexaenoic acid (DHA, 22:6 n − 3) contents. Eggs from hens fed the HF diet showed increased linolenic acid (46 mg/yolk) and DHA (71 mg/yolk, 1.7% of total fatty acids) contents. These levels were obtained after two weeks of feeding. Moreover, the fatty acid profiles of eggs from treatment HF were not significantly affected by thermal treatment of the yolks. In conclusion, the fat from horse bone medulla, as produced in Uruguay, can be considered as a suitable lipid source for diets of laying hens, to modify the nutritional composition of the eggs in n − 3 PUFA content, especially DHA, and consequently, the n − 6/ n − 3 fatty acid ratio.