Improving the incubation results by sealing the eggshell of cracked hatching eggs with surgical tape.

In broiler breeder production, up to 2% of hatching eggs are rejected because of cracked or broken shells. Eggs with cracks give a reduced hatchability and a lower chick quality and cause economic loss. The main goal of this study was to determine the effect of sealing eggshell cracks with surgical tape on hatching parameters. A total of 3,000 eggs from a 34 weeks old Cobb 500 broiler breeder flock was used in the experiment. Six hundred intact eggs represented a positive control. Other eggs were artificially cracked by the operator either on the first day of storage (1,200 eggs) or on the fourth day of storage (1,200 eggs). In both groups, cracks on 600 eggs were sealed by the adhesive surgical tape while the other 600 eggs remained untreated and were used as a negative control. Within each experimental group, eggs were assigned randomly to 4 setter trays representing 4 replicates of 150 eggs. The egg weight loss during incubation was the highest (P < 0.01) in groups of nonsealed cracked eggs. The egg weight loss in sealed groups was higher compared to the control group (P < 0.01). Percentage of egg contamination was not different between groups. Embryonic mortality was higher in non-sealed groups in all stages of embryonic development (P < 0.01) compared to groups of sealed cracked eggs and the control group. Hatching percentage was significantly lower in non-sealed groups (P < 0.01) compared to sealed groups and positive control. No significant difference in hatching parameters was observed between sealed groups and positive control, indicating that surgical tape can be used for sealing cracks on the eggshell to support embryonic survival.

Effects of housing systems on keel bone damage and egg quality of laying hens.

The aim of this study was to investigate whether keel bone damage is prevalent in laying hens in Greece. The study was conducted in three industrial farms using different housing systems: (a) enriched cages, (b) floor system, and (c) free-range system. One hundred hens per housing system, randomly selected, were evaluated for keel bone damages with the method of palpation. Complementarily, thirty eggs from each farm were selected for the measurement of egg weight, shape index, shell cleanness, shell color, shell breaking force, shell thickness, shell weight, egg yolk color, albumen height, and Haugh unit. The presence of keel bone damage was evident in all housing systems with the significantly highest occurrence being observed in the free-range system (50.00%), followed by enriched cages (24.00%) and floor system (7.00%). Eggs from all three systems had significant differences in all estimated egg quality parameters apart from shell color and Haugh unit.