HATCHABILITY AND PHYSIOLOGY OF TURKEY EMBRYOS INCUBATED AT SEA-LEVEL WITH INCREASED EGGSHELL PERMEABILITY

Turkey eggs were incubated in a commercial hatchery to test the effects of increasing eggshell permeability on hatchability and embryonic physiology. Fertile eggs were distributed randomly into two groups on the farm. One group (P) was washed in a 3,500 ppm sodium hypochlorite solution to remove the eggshell cuticle and increase permeability. A control group (CON) of eggs was washed using standard egg washing procedures that left the cuticle intact. The P treatment increased eggshell water vapor conductance 20.7% compared with CON but did not significantly (P greater-than-or-equal-to .05) affect hatchability of eggs compared with CON. The P treatment increased (P less-than-or-equal-to .05) hemoglobin concentration during the hatching process by increasing (P less-than-or-equal-to .05) red blood cell numbers and increasing (P less-than-or-equal-to .05) mean cellular hemoglobin. The P treatment also decreased (P less-than-or-equal-to .05) mean cellular volume of erythrocytes prior to external pipping compared with intact CON eggs. Increasing permeability elevated (P less-than-or-equal-to .05) embryonic lung and liver weights in P embryos compared with CON embryos, but the P treatment also decreased (P less-than-or-equal-to .05) heart weight at hatching compared with CON. It was concluded that although the P treatment did not affect hatchability, embryos in eggs with increased eggshell permeability make different physiological adjustments to survive the hypoxia of hatching than do embryos in intact eggs.