Ultrasonographic measurements of accessory sex glands, ampullae, and urethra of normal stallions of various size types.

This research conducted an ultrasonographic examination on accessory sex glands, ampullae, and the pelvic urethra of stallions. Findings revealed that size measurements of these organs were generally larger in bigger horses compared to miniature horses and ponies, with exceptions noted for vesicular glands. The research established clinical reference values for these measurements, which can aid in veterinary care.

Methodology

• The study used 102 mature, healthy breeding stallions, aged between 2 and 29 years and varying in size types, including miniature horses, small ponies, light horses, and heavy horses.
• Ultrasonographic examinations and measurements of the stallions’ accessory sex glands, ampullae, and pelvic urethra were conducted using an Aloka 210 scanner equipped with a 7.5 MHz linear veterinary transrectal transducer. These proceedings were done per rectum, with most horses being unsedated.

Findings

• The study discovered that measurements of the accessory sex glands, ampullae, and urethra were generally larger in bigger horses. The measurements for all glands were mostly smaller for miniature horses and ponies than for light and heavy horses. Exceptions were noted for vesicular glands, which were larger in heavy horses.
• No significant asymmetry was found between left and right paired glands.
• For vesicular glands and ampullae, as well as prostate lobe thickness, some asymmetry was observed. This means that the size or shape of these organs may not be identical on both sides of the horse’s body.
• Among light horse breeds, Arabian stallions had the smallest mean values for the majority of the measures.

Echogenic Characteristics and Lumen Contents

• The study observed wide variations in the echogenic characteristics – the ability of an organ to reflect ultrasound waves – of accessory sex glands, particularly vesicular glands, potentially due to differences in recent sexual activity.
• In some stallions, remarkable variations were observed between left and right vesicular glands.
• The ampullae, a part of the stallion’s reproductive system, had wide variations in lumen contents between stallions. The lumen is the inside space of a tubular structure, like an artery or intestine. It is where the biological matter is transported. Wide variation in ampullae lumen content suggests that different stallions may transport different amounts of biological matter in this part of their reproductive system.

Implications

• The findings are in line with previous reports and in vitro studies. This adds credibility to the research as it validates previous findings and contributes new information to the field.
• The study provides useful clinical guidelines for size measures of accessory sex glands in horses. This means veterinarians now have reference values they can use when taking these measurements in clinical settings.