## 2 Materials and Methods  
### Screening of Physical Attributes of Hen Eggs  
Fresh eggs were obtained from the company JSC \"Balticovo\" (Iecava, Latvia) from three laying hen breeds: Lohmann Sandy (42 weeks old, enriched cage housing), H&N Coral (41 weeks old, enriched cage housing), H&N Coral (41 weeks old, cage-free housing), and Dekalb (43 weeks old, cage-free housing). To evaluate the egg physical-chemical properties' change as a function of storage time, 180 eggs from each hen breed were collected within 4 h of being laid. Harvested eggs were packed individually per 16 pc in cardboard packaging with a perforated lid. The total number of harvested eggs amounted to 720 eggs. At the initial stage of storage, 16 eggs from each group were taken and immediately delivered to the laboratory of JSC \"Balticovo\" for the screening of quality attributes. At the same time, the remaining part of the eggs was placed in a humidity and temperature-controlled storage room for subsequent storage. The eggs were stored under controlled conditions at 20 \({}^{\circ}\)C with 50% relative air humidity. The length of the experiment was 36 days. To elucidate the changes in quality indicators, eggs' physical-chemical properties were analyzed once every four days, i.e., 1, 4, 8, etc., (except for 8-11, 11-15, and 15-18 days) during 36 days of storage. In the successive days of storage, 16 eggs per breed were taken to ensure an average sample.  
At selection, eggs were weighed and cracked onto a flat surface. The heights of the inner thick albumen and Haugh unit were measured with an electronic albumen height digital Haugh tester ORKA (Bountiful, UT, USA) as proposed by [PERSON] et al. (2015). The pH of the albumen was measured immediately after laying with a pH-meter Jenway 3510 Benchtop pH Meter (Barloworld Scientific, Staffordshire, UK) according to ISO 1842:1991. The shell thickness was measured using a micrometer Mitutoyo 223-101 (Kawasaki, Japan). Shell strength was determined utilizing the FUTURA Egg-Shell-Tester V. 2.0 (Lohne, Germany) tester equipped with an aluminum compression disc 7.62 cm in diameter attached to the unit and an egg holder. The egg was placed so that the disc contacted the eggs from the large end of the egg. Dry matter was analyzed using a Shimadzu MOC-120H (Shimadzu Corporation, Tokyo, Japan) moisture analyzer.  
The trials were conducted in a commercial layer house JSC \"Balticovo\" in 2022. The diets and drinking water were offered _ad libitum_. The ingredients and chemical composition of the basal diet are presented in Table 1. Diets were in mash form. Laying hens were housed in layer cages, the size of which were L: 2.4 \(\times\) W: 0.6 \(\times\) H: 0.5 m (0.14 m\({}^{2}\) per hen), and in cage-free conditions.  
\begin{table}
\begin{tabular}{l c c} \hline \hline \multicolumn{1}{c}{**Ingredient**} & \multicolumn{1}{c}{**H/LS/CCE, H/HN/CCE**} & \multicolumn{1}{c}{**H/D/BWE**} \\  & \multicolumn{1}{c}{**H/HN/BCE**} & \multicolumn{1}{c}{**H/D/BWE**} \\ \hline
**Ingredient** & \multicolumn{1}{c}{**Content, \%**} & \\ \hline Corn & 11.00 & 15.00 \\ Wheat & 47.00 & 36.00 \\ Trticale & 0.00 & 4.00 \\ Barley & 4.00 & 14.00 \\ Soybean press cake & 12.97 & 7.96 \\ Sunflower seeds & 10.80 & 9.40 \\ Oat & 2.00 & 1.80 \\ Sunflower/Rape oil & 1.50 & 1.00 \\ Other composition/premix & 10.73 & 9.65 \\ \hline \hline \end{tabular} Note: H/LS/CCE—Lohmann Sandy (hens aged 42 weeks, enriched cage housing, cream eggs); H/HN/CCE—H@N Coral (hens aged 41 weeks, enriched cage housing, cream eggs); H/HN/BCE—H@N Coral (hens aged 41 weeks, cage-free housing, cream eggs); and H/D/BWE—Dekalb (hens aged 43 weeks, cage-free housing, cream eggs); and H/D/BWE—Dekalb (hens aged 43 weeks, cage-free housing, cream eggs).  
\end{table}
Table 1: Composition of feed base formula used for feeding laying hens.