Bull Reproductive Organs - Lecture Notes

Overview

• Focus on bull reproductive organs.
• Reference structure of a bull's body: tail, hindquarters, head.
• Exam expectations: no sketching required, likely labeling exercises.

Key Organs and Structures

Testicles

• Bulls have two testicles (only one visible in diagrams).
• Functions: production of sperm and testosterone.
• Epididymis: stores sperm, located around testicles.
• Scrotum: skin area holding testicles, outside the body.

Sperm Pathway

• Vas Deferens: tube connecting testicles to reproductive organs.
  • Ampulla: thickened part for more sperm passage.
• Seminal Vesicles: secrete nutrients for sperm.
• Prostate Gland: secretes an alkaline solution to neutralize female's acidic environment.
• Urethra: pathway for sperm and urine.
• Cowper's Glands: secrete mucus to lubricate sperm.
• Retractor Muscle: controls penis movement (retraction and extension).

Functions of Organs

Testicles and Hormones

• Spermatogenesis: sperm production process.
• Cells of Leydig: produce testosterone, provide male characteristics.

Sperm Structure

• Head: includes acrosome (with enzymes) and nucleus (DNA).
• Mid-piece: contains mitochondria (energy for swimming).
• Tail: propels sperm.

Accessory Glands

• Epididymis: stores sperm, creates semen (sperm + fluids).
• Vas Deferens: transports semen.
• Ampulla: top of vas deferens, thick part.

Additional Glands

• Seminal Vesicles: secrete nutrients, regulate semen pH.
• Prostate Gland: secretes alkaline solution.

Fertility Issues

Infertility vs. Sterility

• Infertility: sperm production but unsuccessful mating/fertilization.
• Sterility: no or deformed sperm.

Causes of Infertility

• Sexual immaturity or inexperience.
• Exhaustion, malnutrition, diseases.
• Temperament (lack of libido), environmental changes.
• Impotence (erection issues).

Causes of Sterility

• Climate effects (high temperatures).
• Malnutrition, diseases affecting sperm.
• Infections or injuries to sex organs.
• Congenital deformities (genetic defects).

Homework

• Review and understand the functions and structure of the bull reproductive system.
• Familiarize with terms and definitions discussed in the lecture.