Ferret Reproduction - Anatomy & Physiology

()Map REPRODUCTIVE SYSTEM (Map) SMALL DOMESTIC MAMMALS

MALE

• Male is known as the Hob.

Penis

• J-shaped os penis lies within the caudal section of the penis dorsal to the penile urethra.
  • Makes catheterization difficult.
  • Supporting bone is the Baculum.
• Penis points cranially.
• Opening of the prepuce is on the ventral abdomen.

Testes =

Introduction

Two testes are carried externally in the scrotum. Once testes have descended, the inguinal canal closes and they are not able to be retracted. Spermatogenic activity increases within the semniferous tubules of the testes from December-July. Testes become noticeably enlarged in preparation for the breeding season (March-August).

Structural Anatomy

• Epididymis is composed of a mass of convoluted spermatic duct.
  • Divided into head, body and tail on the dorsal aspect of the testis as it lies in the scrotal sac.
  • Head of the epididymis receives efferent ducts as they leave the testes at the cranial pole.
  • Body of the epididymis has the main mass of the convoluting spermatic duct, which passes to the tail of the epididymis at the caudal pole of the testes.
• Spermatic duct is a simple duct to the tail of the epididymis.
  • Passes cranially on the dorsal aspect of the testes as the ductus deferens.
    • Medial to the body of the epididymis.

Blood Supply, Nerves and Lymphatics

• Ductus deferens is accompanied by the deferent artery and vein.
  • With the nerves and lymphatic vessels, form the spermatic cord.
• Spermatic cord passes cranially to the inguinal canal into the abdomen.
• Testicular artery then splits off from the spermatic cord.
• Spermatic cord continues, looping over the urethra through the prostate gland.

Histology

• Testes, blood vessels, nerves, lymphatics and ductus deferens are wrapped in a pouch of peritoneum called the Vaginal Sac.
  • Extends through the inguinal canal in development prior to testicular descent.

Accessory Glands

• The only accessory sex gland is the prostate gland.
  • A fusiform enlargement around the proximal part of the urethra at the neck of the bladder.
  • Adds elements to the seminal fluid.
  • Not very distinct in the young ferret.
• At the level of the prostate, the ductus deferens from each side opens into the urethra.

Puberty and Sexual Maturity

• Males mate the year after they are born.

FEMALE

• Known as the Jill.

Reproductive Tract

Ovary

• Left ovary lies caudal to the middle of the 14th rib and caudal to the left kidney.
• Right ovary is caudal to the middle of the last rib (15th) and caudal to the right kidney.
• Ovaries are suspended by ligaments from the abdominal wall.

Uterus

• Bicornuate uterus
  • Long uterine horns
  • Small Uterine Body
• Blood supply is from the ovarian and uterine arteries and veins.
• Sympathetic innervation from the aortic and renal plexuses.

Vulva

• Vulva lies on the perineum, ventral to the anus.
  • During the non-breeding season, it is small and slit-like.
  • During oestrus it becomes swollen and resembles a small doughnut.

Puberty and Sexual Maturity

• Sexually mature at 6-8 months of age.
• Females mate the year after they are born.

Oestrous Cyclicity

• Seasonally polyoestrus
  • Breeding season is from March for 2-3 months.
    • Long day breeders
• Oestrus is shown by a swollen, pink vulva which regresses 2-3 weeks after mating.
• Induced ovulator
  • If mated, ovulation occurs within 30-40 hours of coitus.
  • If not mated, may remain in continual oestrus for up to ~4 months.
    • Unmated jills can die from postoestrus non-regenerative anaemia.
    • Continual stimulation of oestrogen to the ovaries, leading to hyperoestrogenism.
    • Excess oestrogen supresses bone marrow activity.
    • Symptoms include swollen vulva, allopecia and anaemia.

Copulation

• Initiated on the 14th day after the onset of vulval swelling.

Gestation

• Gestation period is 42 days.
• Placenta is zonary.

Litter

• Average litter 8-10 kits, but can be as large as 18.
  • Kits can hear from 32 days.
  • Eyes open at 4-5 weeks.
  • Weaned at 6-8 weeks.