Changes in Fatty Acids Profile, Health Indices, and Physical Characteristics of Organic Eggs from Laying Hens at the Beginning of the First and Second Laying Cycles

Abstract

The present study compared the fatty acid profile and some physical parameters of eggs from hens reared according to the organic system at the beginning of the first and second laying cycle. A total of 1080 eggs were analysed at the beginning of the first (from the 28th to 30th week of age) and the second (from the 78th to 80th week of age) laying cycle. It was found that the hen ages influenced the egg weight, egg surface area, yolk proportion, and eggshell colour. Albumen and eggshell proportion, albumen, yolk index, Haugh unit score, and eggshell strength were lower in eggs from older hens compared with those produced from younger layers. Monounsaturated fatty acids were found in higher amounts than saturated fatty acids and polyunsaturated fatty acids in egg yolks of eggs from layers only at the beginning of the second laying cycle. The PUFAn-6/n-3 ratio, saturation, atherogenic, and thrombogenic indices were significantly lower in the egg yolks from older hens compared to younger layers. These findings (regarding the eggs from the older ones) prove that it is practical to utilize them in the organic farming system during a period of two years.

Variation in the Fatty Acid and Amino Acid Profiles of Pasteurized Liquid Whole Hen Egg Products Stored in Four Types of Packaging

“…In total, 28 FAs were identified and quantified, among which the prevalence of oleic acid (C18:1n9c) (42.45%), followed by palmitic acid (C16:0) (23.49%), linoleic acid (C18:2n6c) (8.86%), and stearic acid (C18:0) (6.64%) were observed at the initial stage of storage ( Figure 3 ). The results are consistent with those of Zita et al [ 37 ], indicating a fairly similar descending order of FA content recovered from organic eggs. As seen, storage resulted in a sharp decrease in FAs, and the percentage reduction was time and packaging type-dependent.…”

Comparison of Fatty Acid Profile in Egg Yolk from Late-Age Hens Housed in Enriched Cages and in a Free Range System

“…Dalle Zotte et al [3] did not find any significant effect of production systems (cage, barn, and organic) on the above-mentioned indexes. Regarding the age-related effect, it was found that the fatty acid composition of egg yolks from late-age laying hens resulted in lower AI and TI values compared with early-age laying hens [43,45], and the detected values were in the same range of our results.…”

“…Regarding the agerelated effect, it was found that, in eggs from late-age laying hens, it was higher compared with early-age laying hens (22.3 vs. 18.2) but similar to intermediate ones (22.2) [45]. Conversely, Zita et al [43] did not find any age-related effects on the n-6/n-3 ratio during the first and second laying cycles (16.56 vs. 18.24, respectively). PUFA/SFA is a commonly used index for evaluating the nutritional value of dietary foods; it hypothesizes that all PUFAs in the diet can depress low-density lipoprotein cholesterol (LDL-C) and lower levels of serum cholesterol, whereas all SFAs contribute to high levels of serum cholesterol.…”

“…Total FA (SFA, MUFA, PUFA, n-3 PUFA, and n-6 PUFA) and individual fatty acids did not differ significantly from the 68th to 74th week of age (p > 0.05). In a recent study carried out by Zita et al [43] on eggs from Lohmann Brown layers-analyzed at the beginning of the first (from the 28th to 30th week of age) and second (from the 78th to 80th week of age) laying cycle-it was found that egg yolks from the second laying cycle had higher MUFA and lower SFA and PUFA contents compared with those of the first laying cycle. In this case, the highest value of MUFA in the second laying cycle was due to a higher amount of oleic acid (+6%), probably due to the significant impact of feeding management on oleic acid [44] or different total lipid contents in the egg yolk of the second laying cycle.…”

Effects of dietary supplementation of glycerol monolaurate on laying performance, egg quality, antioxidant capacity, intestinal morphology and immune function in late-phase laying hens

“…In the late phase of laying production, due to the degradation of intestinal absorption function and the decline in antioxidant as well as immune function of laying hens lead to a decline in egg quality, resulting in huge economic losses in the poultry industry ( Feng et al, 2020 ; Dai et al, 2022 ; Zita et al, 2022 ). Dietary GML supplementation significantly affects the egg quality.…”