Effect of Prudhoe Bay Crude Oil on Hatching Success and Associated Changes in the Pipping Muscle (musculus Complexus)in Embryos of Domestic Chicken

Fertile White Leghorn chicken eggs were exposed to 0,1,2,4,6,8, and 16 ÎL of Prudhoe Bay Crude oil (PBCO) on day 9 of incubation. The effects of oil on percentage pipping,percentage hatchability, body weight gains post hatching,serum creatine kinase and pathological changes in the pipping (hatching) muscle (musculus complexus), liver, bursa of Fabricius and other organ systems were assessed during the hatching period in embryos that had survived acute toxicity and were alive on day 18 of incubation. Oil treatment greatly reduced hatchability and percentage pipping (Chi-square: p=0.0001). Severe edema and hemorrhage of the pipping muscle, multifocal subcapsular hepatic necrosis, lymphoid atrophy in the bursa of Fabricius with infiltration by heterophils and occasional dorsocaudal subcutaneous edema were observed in oil exposed embryos. Pipping muscle wet weight was greater in oil-exposed embryos (t test: p =0.001). Body weight gain post-hatching was significantly reduced in embryos exposed to 4 uL of PBCO (ANOVA: p<0.05). Serum creatine kinase (CK) levels were elevated only at the time of hatching in the oil-exposed embryos (t test: p = 0.047). Dysfunction of the pipping muscle in oil-exposed embryos may account for reduced pipping rates and hatchability.