Ascaris lumbricoides

Fertilized egg

• 75×50 micrometer , brownish due to the bile pigment.
• Outermost egg shell layer is a mammalated albuminous coat.
• Thick egg shell, especially chitinous layer.
• Usually find a one- cell stage in freshly passed faeces.

Fertilized, Decorticated egg

• Broadly ovoid with a thick shell transparent.
• No outer albuminous layer.
• One-cell stage.

Unfertilized egg

• 90×55 micrometer , brownish.
• Elongated ovoidal in shape.
• Egg shell is thinner than the fertilized Ascaris egg.
• It contains a mass of disorganized , highly refractive granules of various sizes.