Chemical Compositions of Egg Yolks and Egg Quality of Laying Hens Fed Prebiotic, Probiotic, and Synbiotic Diets

Abstract

A 16-wk feeding experiment was conducted to investigate the effects of a prebiotic, isomaltooligosaccharide (IMO), a probiotic, PrimaLac®, and their combination as a synbiotic on the chemical compositions of egg yolks and the egg quality of laying hens. One hundred and sixty 16-wk-old Hisex Brown pullets were randomly assigned to 4 dietary treatments: (i) basal diet (control), (ii) basal diet + 1% IMO (PRE), (iii) basal diet + 0.1% PrimaLac® (PRO), and (iv) basal diet + 1% IMO + 0.1% PrimaLac® (SYN). PRE, PRO, or SYN supplementation not only significantly (P < 0.05) decreased the egg yolk cholesterol (24- and 28-wk-old) and total saturated fatty acids (SFA; 28-, 32-, and 36-wk-old), but also significantly (P < 0.05) increased total unsaturated fatty acids (UFA; 28-, 32-, and 36-wk-old), total omega 6 and polyunsaturated fatty acids (PUFA), including linoleic and alpha-linolenic acid levels in the eggs (28-wk-old). However, the total lipids, carotenoids, and tocopherols in the egg yolks were similar among all dietary treatments in the 24-, 28-, 32-, and 36-wk-old hens. Egg quality (Haugh unit, relative weights of the albumen and yolk, specific gravity, shell thickness, and yolk color) was not affected by PRE, PRO, or SYN supplementation. The results indicate that supplementations with IMO and PrimaLac® alone or in combination as a synbiotic might be useful for improving the cholesterol content and modifying the fatty acid compositions of egg yolk without affecting the quality of eggs from laying hens between 24 and 36 wk of age.

Beneficial effect of feeding olive pulp and <i>Aspergillus awamori</i> on productive performance, egg quality, serum/yolk cholesterol and oxidative status in laying Japanese quails

“…The possible mechanisms by which A. awamori exerts effect are: its superior ability to secrete enzymes able to degrade the non-starch polysaccharides (NSP) and fibre contents of OP, and its role as a probiotic. In addition, the ability to lower egg cholesterol levels had been previously reported for both OP (Hashish and Abd El-Samee, 2005;Saleh et al, 2017) and A. awamori (Imaizumi et al, 1992;Hara et al, 1999;Tang et al, 2015), and this coincides with the increasing demand for low-cholesterol or unsaturated fatty acids in eggs. Therefore, in this study, laying quails were selected as experimental subject to examine the effect of OP with or without A. awamori dietary inclusion on their productive performance, egg quality, and biochemical and antioxidant status.…”

“…Moreover, Saleh et al (2017) found a significant decrease in the yolk cholesterol in groups fed A. awamori. Other researchers observed also the beneficial effects of probiotic on egg quality such as lower cholesterol content (Mikulski et al, 2012;Tang et al, 2015).…”

“…OP and A. awamori showed noteworthy decrement effect on yolk total lipids and yolk cholesterol during the third experimental period (16-20 week of age) and the overall one (8-20 week of age) ( Table 5). Little is known about the mechanism by which probiotics reduce the cholesterol content in eggs (Tang et al, 2015). However, the proposed mechanism by which A. awamori decrease yolk cholesterol content might be attributed to the fermentation occurred by A. awamori, which produces short-chain fatty acids that suppress hepatic cholesterol synthesis (Hara et al, 1999) and stimulate bile acid synthesis (Imaizumi et al, 1992).…”

“…However, the proposed mechanism by which A. awamori decrease yolk cholesterol content might be attributed to the fermentation occurred by A. awamori, which produces short-chain fatty acids that suppress hepatic cholesterol synthesis (Hara et al, 1999) and stimulate bile acid synthesis (Imaizumi et al, 1992). Moreover, A. awamori, as a probiotic, has the ability to alter the pathways of cholesteryl-esters and lipoprotein transporters (Liong et al, 2007), which might reduce the availability of cholesterol for deposition into egg yolks (Tang et al, 2015). Whereas, yolk cholesterol-lowering effect of OP may be due to its high contents of unsaturated fatty acids, especially n-3, n-6 and n-9, which might affect the quality of yolk-lipids contents (Hashish and Abd El-Samee, 2005).…”

Polyphenols in Eucalyptus leaves improved the egg and meat qualities and protected against ethanol‐induced oxidative damage in laying hens

“…Hen eggs have been consumed by humans for thousands of years because they are nutritionally dense, relatively simple and are accepted in most cultures. Despite the nutritional value, there are some potential health issues arising from high level of cholesterol in the egg yolk (Tang et al., ). It is well known that eggshell quality and egg trait are of major importance to the customer preference.…”