Effect of hen age, environmental temperature, and oviposition time on egg shell quality and egg shell and serum mineral contents in laying and broiler breeder hens

Abstract

ABSTRACT:The aim of the study was to evaluate egg shell quality characteristics, mineral content in the egg shell, and serum mineral concentration during the egg formation process as influenced by oviposition time and ambient temperature at the beginning and end of the laying cycle in laying hens and broiler breeders. Egg shell quality deteriorated significantly at the higher temperature and was lower in broiler breeders than in laying hens. The Ca (P = 0.047) and P (P = 0.018) contents of the egg shell were significantly higher at the higher temperature. The highest (P = 0.028) shell Ca content (352 g/kg) was in eggs laid in the morning, but the highest P (P = 0.030; 1.43 g/kg) and Mg (P = 0.001; 3.88 g/kg) contents were in eggs laid in the afternoon. Broiler breeder egg shells contained significantly more P (P = 0.004) and Mg (P = 0.001) than did those from laying hens. Serum Ca and P levels remained constant throughout the day whereas serum Mg and Zn levels decreased, the rate of decrease in Zn content being the same in all treatments, but with the amounts being greater in laying hens than broiler breeders. The results demonstrate that shell quality characteristics are more severely affected by different factors implemented in this trial compared to the shell mineral composition and especially compared to the serum mineral content.

The effect of essential oils on quality and mineral composition of eggshell

“…, Mg 3.32 g kg -1 and Zn 4.82 g kg -1 were observed in egg shell of Lohmann Brown laying hens (Tůmová et al, 2014).…”

“…Park et al (2015) presented eggshell thickness of layers in the range from 0.37 to 0.40 mm. Tůmová et al (2014) indicated average eggshell thickness of Lohmann Brown laying hens 0.31 mm.…”

“…Differences in egg shell physical parameters are dependent, among other factors, on the rate and extent of mineral deposition in the egg shell (Tůmová et al, 2014). Eggshell strengths of bursting and eggshell thickness are expressed in Table 2.…”

The effect of essential plant oils on mineral composition of egg mass and blood parameters of laying hens

“…Feeding olive oil along with conjugated linoleic acid completely prevented changes in the mineral content of egg yolk and albumen. Average contents of Ca 344 g*kg were observed in egg shell of Lohmann Brown laying hens (Tůmová et al, 2014). Glisson and Walker (2010) reported that sodium, potassium and chlorides occurs for the most part as free minerals and other minerals are usually bound to proteins and phospholipids.…”

“…Present findings are not in agreement with those presented by Levkut et al (2011) who observed that chickens fed oregano oil supplemented diet had significantly higher serum magnesium concentration and slightly lower serum phosphorus level in comparison with birds from control group. Tůmová et al (2014) found average contents of serum Ca 4.18 mmol*l Enzymatic profile of blood of laying hens at the end of experiment is recorded in Table 5. AST, ALT, GGT, ALP and bilirubin of enzyme complex were observed in this trial.…”