Welcome again. I hope you are fine and completed the previous articles. Today, I will discuss the Comparative Anatomy of Urinary Organs from Different Animals like oxs, sheep, goats, horses, and dogs.
You may continue this article to learn about the comparative anatomy of urinary organs from different animals. After reading this article, you can identify the basic differences between different urinary organs from different animals. Okay, let’s start to know.
I hope you have a basic knowledge of the anatomy of organs in the urinary system of animals. If you want to memorize these, I recommend visiting this link. If you already have a better knowledge, then you may skip this.
“I will compare these organs from the urinary system based on the most important features. If you want, you may compare with more features.”
Comparative anatomy of urinary organs
We will learn the comparative anatomy of the following urinary organs from different animals: ox, sheep, goat, horse, and dog. It would help if you also compared among other different species.
- Comparative anatomy of kidney
- Comparative anatomy urinary bladder
- Comparative anatomy of the urethra
Okay, let’s start –
Comparative anatomy of kidneys of different animals
We will consider the following most important features to compare the kidney among different animals like oxs, sheep, goats, horses, dogs, and also cats –
Shape of kidney
Elongated elliptical and flattened dorso-ventrally in ox, bean-shaped in goat
The right kidney is heart-shaped, and the left is bean-shaped in the horse.
Bean-shaped dog
Surface of kidneys in different animals
Lobulated in ox, but smooth in case of goat
Smooth surface in horse
Also, smooth surfaces in dog
Renal pyramid or crest
Renal pyramid is present in oxes and dogs but not prominent in the horse
Renal crest is present in horse and dog
Location of kidney (right)
Ventral to the last rib and first 2 or 3 lumbar transverse processes (in ox, sheep, and goat)
Last 2 or 3 ribs and first lumbar transverse process (in horses)
Opposite to the body of 1st to 3rd lumbar vertebrae as far cranial as the last thoracic) – in dog
Location of the kidney (left)
Ventral to 3rd or 4th or 5th lumbar vertebrae (body) in ox, sheep, goat (rumen full)
Ventral to last rib and 1st 2 or 3 lumbar transverse processes in the horse
Ventral to the body of 3rd or 4th or 5th lumbar (stomach full)
Okay, it is better to learn from the table. Let’s see –
| Features | Ox, sheep and goat | Horse | Dog |
| Shaped | Elongated elliptical (cattle) Bean shaped (goat) | Right – heart shaped Left – bean shaped | Bean shaped |
| Surface | Polygonal lobes by fissures (cattle) Smooth (goat) | Smooth | Smooth, dark brown or red or blue red colored |
| Right kidney (position) | Ventral to the last rib and first 2 or 3 lumbar transverse process Caudal and ventral to 1st three lumbar transverse process | Last 2 or 3 ribs and 1st lumbar transverse process | Opposite to body of 1st three lumbar vertebrae (may be as far cranial as last thoracic) |
| Left kidney (position) | Ventral to 3rd or 4th or 5th lumbar vertebrae (body) – when rumen is full Same level and partly at left side of median plane (when rumen empty) | Ventral to last rib and 1st 2 or 3 lumbar transverse process | Ventral to the body of 3rd or 4th or 5th lumbar vertebrae (when stomach full) Ventral to body of 2nd or 3rd or 4th lumbar vertebrae (when stomach empty) |
| Renal pyramid or renal crest | Renal pyramid -easily observed, projected into major calics | Renal pyramid is not prominent Renal crest present | Renal pyramid present Renal crest present |
Comparative anatomy of the urinary bladder from different animals
We need to consider the following most important features to compare the urinary bladder among different animal species –
- The shape of the urinary bladder
- It is pyriform in ox, sheep, and goat (in empty condition) but ovoid when filled.
- Pyriform and ovoid in horse
- Pear-shaped in dog
Let’s start to learn from the table below –
| Features | Ox, sheep and goat | Horse | Dog |
| Shape | Pyriform Ovoid (when fills) | Pyriform Ovoid | Pear shaped |
| Parts of bladder | Body, neck and apex | Body, neck and apex | Body, neck and apex |
| Middle and lateral ligament | Present | Present | Present |
Comparative anatomy of urethra among different animals
We will consider the following important features to compare the anatomy of the urethra from animals –
Origin and destination of the urethra
- In males – the neck of the urinary bladder to the glans penis (ox, sheep, and goat)
- In females – the internal urethral orifice to the seminal colliculus (ox, sheep, and goat)
Suburethral diverticulum
- A suburethral diverticulum is present in oxes, sheep, and goats but absent in horses and dogs.
Parts of the urethra in male
In ox, sheep, and goats – the urethral muscle encloses the pelvic part, and the extrapelvic part –passes to the glans penis and is projected cranially in the fossa of the glans.
In horses – the pelvic part is enclosed by the urethral except for its origin.
In dogs – the pelvic part is long
Let’s start to know from the table.
| Features | Ox, sheep and goat | Horse | Dog |
| Origin and destination | In male – neck of the urinary bladder to the glans penis In female – lies from internal urethral orifice to seminal colliculus | Same | Same |
| Suburethral diverticulum | Present | Absent | Absent |
| Parts of urethra | In male Pelvic part – enclosed by urethralis muscle (ventrally and laterally) Extrapelvic part – passesto glans penis and projected cranially in fossa of glans – passes between crura of penis and run along groove on ventral surface of corpus cavernosum penis | In male Pelvic part – enclosed by urethralis muscle (except it’s origin) | In male – pelvic part is longer |
| In female – lies on pelvic floor and related to vagina (dorsally) | |||
| Muscles of urethra | Urethralis muscle – enclosed pelvic part of urethra (ventrally and laterally) Dotrsally by aponeurosis | Enclosed pelvic part of urethra and covered bulbo-urethral gland except at its origin | Same as ox, sheep and goat |
| Bulbospongiosus muscle – extend from ischial arch to gland penis | |||
Conclusion
I hope you got an idea of the comparative anatomy of urinary organs from different animals and will be able to identify these organs from different animals based on their most important anatomical features.
If you think you need more than this information to learn the comparative anatomy of urinary organs of different animals, I recommend you learn from class lectures or books. And again, if you want to learn more about veterinary comparative anatomy, I recommend you connect with me or follow my upcoming articles.
“If possible, I will update or enrich information, pictures, and videos on this topic in the future.”
If there is any mistake in the above information or if you have any suggestions for me, please let me know in the comment box. Thank you so much.
