Oviduct

Question 1

Oviduct

Answer 1

The oviducts (aka fallopian tubes, uterine tubes, salpinx) are tubes running from tip of each uterine horn to each ovary

Four distinct regions

1. utero-tubal junction (UTJ)
2. Isthmus (uterine end, thinner)
3. Ampulla (ovarian end, thicker)
4. Infundibulum (funnel shaped opening)

Role of oviduct is to transport & support oocytes (pre and post-fertilisation) and sperm

Oviduct is where fertilisation occurs not in uterus.

Question 2

Utero-tubal junction

Answer 2

The UTJ is the transition point between the uterus & oviduct – can act as a physical barrier to limit cell/fluid movement

In some species, constriction at the UTJ (muscular or oedema) can restrict:

• Entry of sperm (cow, sow) or
• Exit of oocytes/embryos (mare, ewe)

Question 3

Oviduct regions

Answer 3

Question 4

Isthmus Histology

Answer 4

Simple mucosa & thick muscle layer

Question 5

Ampulla Histology

Answer 5

Elaborately folded mucosa (incr. SA), ciliated (help move oocytes to uterus)and thin muscle layer.
Also has secretory cells.
Poorly developed muscle layer.

Question 6

Infundibulum

Answer 6

The terminal potion of the oviduct. It has finger-like projections (frimbriae) which greatly increase it surface area.

Infundibulum catches oocyte as released from ovary during ovulation – these enter ampulla through ostium (opening)

Question 7

Species Differences cow vs ewe

Answer 7

Similar but more extensive infundibulum in cow than ewe.

Question 8

Species Differences mare

Answer 8

Mare has unique structure – the ovarian fossa (closely associated with infundibulum).
Unlike in other species, the mare always ovulates at this same location, close to infundibulum.
The mare also has a highly convoluted oviduct (R pic)

Question 9

species differences sow and bitch

Answer 9

The sow and bitch have a prominent ovarian bursa (made of mesovarium/mesosalpinx) enclosing the ovary – the infundibulum is part of this structure.
Bitch = only have 1 opening