Effect of Pre-Storage Heating and Period of Storage on Hatchability Traits of Dokki-4 Eggs

Abstract

This study investigated the effects of pre-storage heating and storage period of hatching eggs on hatchability traits and chick quality of Dokki-4 (Egyptian local strain of chickens) laying hens. A total of 3600 eggs were collected from 46-week-old laying hens. Eggs were distributed in a 3x4 factorial arrangement, with three storage times (4, 8 and 12 days at 18°C and 75% RH) and four heat treatments prior to storage (0, 3, 6 and 9 hours at 37.5°C and 56% RH). Eggs were distributed to twelve treatments of 20 replicates. After storage, eggs were incubated under the normal conditions of incubation at the same time. The results showed that the long storage period increased egg weight loss. Hatchability and chick quality results from 8-12 days stored eggs were lower than eggs stored for 4 days. The 6-hour pre-storage heating system substantially improved egg hatchability and chick quality relative to non-heated or 9-hour heating. Important interactions were observed during pre-storage heating × egg storage time for loss in egg weight, hatchability of total and fertile eggs, embryonic mortality and chick quality. When eggs were stored for more than four days, pre-storage heating of hatching eggs for six hours improved hatchability and chick quality compared to unheated eggs or heated for 9 hours. Conclusively, pre-storage heat treatment beneficially affects hatchability traits and chick quality, especially when hatching eggs are stored for long periods.