File:Canine embryo E35-38 image004.jpg

Canine Embryo (E35-38)

Developing canine embryo at day 40 after mating. This may correspond approximately to ~day 35-38 after fertilisation as bitches are ready for mating a few days prior to ovulation. Fetus located within the intact fetal membranes and placenta. The placenta is viewed from the maternal side and is classified as a zonary placenta, forming a complete central girdle in dogs.

A. Fetus located within the intact fetal membranes and placenta. The placenta is viewed from the maternal side and is classified as a zonary placenta, forming a complete central girdle in dogs.

B. Fetus located within intact amniotic sac with opened chorion and placenta. The placenta is viewed from the fetal side and major fetal blood vessels can be seen radiating over the surface of the placenta, the yolk sac is visible on right. On the maternal side, the endometrial blood vessels are bare to their endothelium and come in direct contact with the chorion forming an endotheliochorial placenta.

C. Fetus with amniotic sac removed. The placental cord is visible at the umbilicus. The limbs are well-developed showing paws and claws. The head surface shows sensory development with eye, ear, nose and whiskers (vibrissae) rows.

Scale bar is 1 cm.

Links: E35-38 image 1 | E35-38 image 2 | E35-38 image 3 | E35-38 image 4 | Dog Development

Image Source: Image contributed by Dr Karine Reynaud, Department of Life Sciences and Health and UMR Developmental and Reproduction Biology ENVA, UMR 1198 Biologie du De ́veloppement et Reproduction, 7 Avenue du Ge ́ne ́ral De Gaulle, 94700 Maisons-Alfort, France. CINRA, UMR 1198 Biologie du De ́veloppement et Reproduction, F-78350 Jouy en Josas, France. Who kindly provided these images of the developing dog. Images are for educational purposes only and cannot be reproduced electronically or in writing without permission.