Chemical Characteristics of Whole Eggs From Avian Species: A Comparative Study

Abstract

Egg weight and egg component, chemical composition, fatty acids and cholesterol, amino acids and minerals content in conventional eggs (ostrich, duck, hen and quail) were studied. Results indicated that, the ostrich egg had highest egg weight (g), and so had highest percent of weight and shell, while duck eggs showed highest percent of yolk. For chemical composition, Ostrich egg have had more highest moisture, carbohydrates and cholesterol contents, while highest values of protein, lipid and total ash were obtained by duck egg (at wet weight basis). Oleic, palmitic, linoleic, stearic and palmitoleic acids were the major fatty acids in egg yolk of all studied eggs. The hen egg had highest oleic and stearic acid, while duck egg had highest palmitic acid. The highest linoleic acid was obtained by quail egg and the highest palmitoleic acid was found by ostrich egg. Concerning amino acids content, glutamic acid had the highest one in the protein composition followed by aspartic acid and leucine in all studied eggs. The highest values of aspartic and leucine were obtained by hen eggs, while the highest values of glutamic acid were obtained by ostrich egg. Concerning minerals content, the ostrich egg had the highest values of iron content. The duck egg had highest values of sodium, potassium and zinc content, while the highest values of magnesium and phosphorus were obtained by hen eggs. Finally the highest calcium content was obtained by quail eggs.

A Comparative Study on Nutritional Value of Quail and Chicken Eggs

“…Such result was similar with Al-Obaidi and Al-Shadeedi (2017) and Uzochukwu et al (2017) who reported that the difference between cholesterol content of quail and chicken eggs may be due to the difference between the weight of the yolk of the quail egg and that of the chicken egg. While that result was differing from that according to Sharaf (2011) who recorded that cholesterol content of quail was higher than chicken eggs. The variability of these results may be due to variation in strain, feed, bird growth stage and environmental condition as recorded by Adeniyi et al (2016) Each value represents the mean of three replicates ±SD…”

“…Statistical analysis revealed that a significant difference (P<0.05) was appeared in phosphor content. Similar finding was obtained by Sharaf (2011). Quail eggs had the lowest values of calcium, zinc, sodium and potassium content than chicken eggs.…”

A preliminary study on the glycosylation of the reproductive tract in the Ostrich (Struthio camelus camelus)

“…This composition may be reflected by the binding of CON A (mannose), DSA, STA, AHA and ECA (GlcNAc), MAA and SNA‐1 (sialic acid) in the ostrich magnum glands, and the low levels of LTA, UEA and ALA stain (fucosyl residues), although inter‐species differences may exist. For instance, ostrich eggs have a higher proportion of firm albumin (77%) than those of the hen (57%; Fernández‐López et al 2006) and a higher percentage of carbohydrate (2.8% wet weight compared to 1.97% in the hen egg; Sharaf, 2011). In the domestic fowl, the shell of the egg also contains a glycosylated protein, ovocleidin, with glucosamine and galactosamine residues (Mann, 1999) which would be synthesized by the cells of the uterus since this area is where the shell is laid down.…”