Popis: |
SUMMARY: The current study investigated the effect of heat processing or carbohydrase enzyme addition on egg production, egg quality, egg fatty acid composition, tocopherol content, and lipid oxidation products in eggs from layer hens fed flaxseed. A total of ninety-six 23-wk-old white leghorn laying hens were kept in individual cages and were randomly allocated to 4 treatment groups, with 6 replicates containing 4 hens per each replicate. The hens were fed corn soybean meal-based diet containing 15 g/100 g raw flaxseed (Flax), 15 g/100 g heated (60°C for 8 h) flaxseed (HFlax), Flax+0.1% enzyme (Flax+E), and HFlax+0.1% enzyme (HFlax+E). The experimental diets were fed for a period of 120 d. Hen-day egg production and egg mass (g/hen/d) were highest for HFlax and HFlax+E and lowest for Flax+E (P < 0.05). No difference was noted in egg, yolk or shell weight, or Haugh unit (P > 0.05). Albumen weight as percentage of egg weight was lower in Flax when compared to HFlax, Flax+E, or HFlax+E (P < 0.05). The yolk:albumen ratio was higher in Flax that in HFlax, Flax+E, and HFlax+E (P < 0.05). Yolk color score was highest for HFlax+E and lowest for Flax+E (P < 0.05). No effect of diet on egg total lipid, palmitic, stearic, α-linolenic, eicosapentaenoic, docosahexaenoic, and arachidonic acid content as mg/egg or as percentage of fatty acid methyl esters was observed (P > 0.05). Hens fed HFlax had lower concentration of linoleic acid (mg/egg) than Flax+E and HFlax+E (P < 0.05). The concentrations of oleic acid and total monounsaturated fatty acids (mg/egg) were higher in Flax than those in other treatments (P < 0.05). Eggs from hens fed HFlax+E had lower thiobarbituric acid reactive substances than Flax+E (P < 0.05) and was not different from Flax or HFlax (P > 0.05). No difference was observed in the α-tocopherol content of the eggs (P > 0.05). Enzyme supplementation and heating of flaxseed increased γ-tocopherol content in Flax+E and HFlax+E eggs (P < 0.05). It is concluded that heating flaxseed prior to consumption increases egg production while reducing oleic acid and linoleic acid (mg/egg). Heating flaxseed or enzyme supplementation had no effect on egg weight, α-linolenic acid, total n-3 fatty acids, total lipid, or total tocopherol content of eggs. |