Penile sheath

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Almost all mammal penises have foreskins or prepuces, [1] although in non-human cases, the foreskin is usually a sheath (sometimes called the preputial sheath, [2] praeputium [3] or penile sheath [4] ) into which the whole penis is retracted. In koalas, the foreskin contains naturally occurring bacteria that play an important role in fertilization. [5] In some bat species, the prepuce contains an erectile tissue structure called the accessory corpus cavernosus[ spelling? ]. [6]

Contents

Penile sheath of a Great Dane Great Dane sheath.jpg
Penile sheath of a Great Dane

During musth, a male elephant may urinate with the penis still in the sheath, which causes the urine to spray on the hind legs. [7]

Male dogs have a conspicuous penis sheath. [8]

Penile sheath of a Chihuahua with cryptorchidism Inguinal cryptorchid 1.JPG
Penile sheath of a Chihuahua with cryptorchidism

In stallions, the retractor penis muscle contracts to retract the stallion's penis into the sheath and relaxes to allow the penis to extend from the sheath. [9]

The penis sheath of a male axis deer is elongated and urine-stained. When rubbing trees with their horns, these stags sometimes move the penis back and forth rapidly inside its sheath. [10] Male bison and fallow deer have tufts of fur at the end of their penis sheaths. [11]

In rodents, the length of the prepuce is related to urine marking behavior. [12]

See also

Related Research Articles

<span class="mw-page-title-main">Glans penis</span> End of the penis

In male human anatomy, the glans penis or penile glans, commonly referred to as the glans, is the bulbous structure at the distal end of the human penis that is the human male's most sensitive erogenous zone and primary anatomical source of sexual pleasure. The glans penis is present in the male reproductive organs of humans and most other mammals where it may appear smooth, spiny, elongated or divided. It is externally lined with mucosal tissue, which creates a smooth texture and glossy appearance. In humans, the glans is located over the distal ends of the corpora cavernosa and is a continuation of the corpus spongiosum of the penis. At the summit appears the urinary meatus and at the base forms the corona glandis. An elastic band of tissue, known as the frenulum, runs on its ventral surface. In men who are not circumcised, it is completely or partially covered by a fold of skin called the foreskin. In adults, the foreskin can generally be retracted over and past the glans manually or sometimes automatically during an erection.

Smegma is a combination of shed skin cells, skin oils, and moisture. It occurs in both male and female mammalian genitalia. In females, it collects around the clitoris and in the folds of the labia minora; in males, smegma collects under the foreskin.

<span class="mw-page-title-main">Clitoral hood</span> Part of the vulva that covers and protects the glans of the clitoris

In female humans and other mammals, the clitoral hood is a fold of skin that surrounds and protects the glans of the clitoris; it also covers the external clitoral shaft, develops as part of the labia minora and is homologous with the foreskin in the male reproductive system. The clitoral hood is composed of mucocutaneous tissues; these tissues are between the mucous membrane and the skin, and they may have immunological importance because they may be a point of entry of mucosal vaccines.

<span class="mw-page-title-main">Paraphimosis</span> Medical condition

Paraphimosis is an uncommon medical condition in which the foreskin of a penis becomes trapped behind the glans penis, and cannot be reduced. If this condition persists for several hours or there is any sign of a lack of blood flow, paraphimosis should be treated as a medical emergency, as it can result in gangrene.

<span class="mw-page-title-main">Phimosis</span> Medical condition

Phimosis is a condition in which the foreskin of the penis cannot stretch to allow it to be pulled back past the glans. A balloon-like swelling under the foreskin may occur with urination. In teenagers and adults, it may result in pain during an erection, but is otherwise not painful. Those affected are at greater risk of inflammation of the glans, known as balanitis, and other complications.

The preputial mucosa of the penis is the epithelium of the inside of the prepuce, or foreskin. To differentiate it from the cutaneous skin of the outside of the prepuce, it is sometimes referred to as the inner mucosa. It starts at the ridged band of the prepuce and continues to the coronal sulcus, where it meets the epithelium of the glans and penile shaft. The preputial mucosa is devoid of hair, as is the cutaneous surface.

<span class="mw-page-title-main">Hypospadias</span> Medical condition

Hypospadias is a common variation in fetal development of the penis in which the urethra does not open from its usual location on the head of the penis. It is the second-most common birth defect of the male reproductive system, affecting about one of every 250 males at birth. Roughly 90% of cases are the less serious distal hypospadias, in which the urethral opening is on or near the head of the penis (glans). The remainder have proximal hypospadias, in which the meatus is all the way back on the shaft of the penis, near or within the scrotum. Shiny tissue that typically forms the urethra instead extends from the meatus to the tip of the glans; this tissue is called the urethral plate.

<span class="mw-page-title-main">Semen collection</span> Process of obtaining semen from male animals

Semen collection refers to the process of obtaining semen from human males or other animals with the use of various methods, for the purposes of artificial insemination, or medical study. Semen can be collected via masturbation, prostate massage, artificial vagina, penile vibratory stimulation (vibroejaculation) and electroejaculation. Semen can be collected from endangered species for cryopreservation of genetic resources.

<span class="mw-page-title-main">Scent gland</span> Exocrine glands found in most mammals

Scent gland are exocrine glands found in most mammals. They produce semi-viscous secretions which contain pheromones and other semiochemical compounds. These odor-messengers indicate information such as status, territorial marking, mood, and sexual behaviour. The odor may be subliminal—not consciously detectable. Though it is not their primary function, the salivary glands may also function as scent glands in some animals.

<span class="mw-page-title-main">Bulbus glandis</span> Anatomical structure

The bulbus glandis is an erectile tissue structure on the penis of canid mammals. During mating, immediately before ejaculation the tissues swell up to lock (tie) the male's penis inside the female. The locking is completed by circular muscles just inside the female's vagina; this is called "the knot" tightening thus preventing the male from withdrawing. The circular muscles also contract intermittently, which has the effect of stimulating ejaculation of sperm, followed by prostatic fluid, as well as maintaining the swelling of the penis and therefore the tie, for some time. For domestic dogs the tie may last up to half an hour or more, though usually less. When male canines are sexually excited, the bulbus glandis may swell up inside the penile sheath, even if the dog has been neutered.

<span class="mw-page-title-main">Stallion</span> Male horse that has not been castrated

A stallion is a male horse that has not been gelded (castrated). Stallions follow the conformation and phenotype of their breed, but within that standard, the presence of hormones such as testosterone may give stallions a thicker, "cresty" neck, as well as a somewhat more muscular physique as compared to female horses, known as mares, and castrated males, called geldings.

<span class="mw-page-title-main">Penile frenulum</span> Band of tissue under the glans penis connecting the foreskin to the ventral mucosa

The frenulum of the penis, often known simply as the frenulum or frenum, is a thin elastic strip of tissue on the underside of the glans and the neck of the human penis. In men who are not circumcised, it also connects the foreskin to the glans and the ventral mucosa. In adults, the frenulum is typically supple enough to allow manual movement of the foreskin over the glans and help retract the foreskin during erection. In flaccid state, it tightens to narrow the foreskin opening.

<span class="mw-page-title-main">Human penis</span> Human male external reproductive organ

In human anatomy, the penis is an external male sex organ that additionally serves as the urinary duct. The main parts are the root, body, the epithelium of the penis including the shaft skin, and the foreskin covering the glans. The body of the penis is made up of three columns of tissue: two corpora cavernosa on the dorsal side and corpus spongiosum between them on the ventral side. The human male urethra passes through the prostate gland, where it is joined by the ejaculatory duct, and then through the penis. The urethra traverses the corpus spongiosum, and its opening, the meatus, lies on the tip of the glans. It is a passage both for urination and ejaculation of semen.

<span class="mw-page-title-main">Penis</span> Primary sexual organ of male animals

In many animals, a penis is the main male sexual organ used to inseminate females during copulation. Such organs occur in both vertebrates and invertebrates, but males do not bear a penis in every animal species.

<span class="mw-page-title-main">Erection</span> Physiological phenomenon involving the hardening and enlargement of the penis

An erection is a physiological phenomenon in which the penis becomes firm, engorged, and enlarged. Penile erection is the result of a complex interaction of psychological, neural, vascular, and endocrine factors, and is often associated with sexual arousal, sexual attraction or libido, although erections can also be spontaneous. The shape, angle, and direction of an erection vary considerably between humans.

<span class="mw-page-title-main">Foreskin</span> Retractable fold of skin which covers and protects the glans of the penis

In male human anatomy, the foreskin, also known as the prepuce, is the double-layered fold of skin, mucosal and muscular tissue at the distal end of the human penis that covers the glans and the urinary meatus. The foreskin is attached to the glans by an elastic band of tissue, known as the frenulum. The outer skin of the foreskin meets with the inner preputial mucosa at the area of the mucocutaneous junction. The foreskin is mobile, fairly stretchable and sustains the glans in a moist environment. Except for humans, a similar structure known as a penile sheath appears in the male sexual organs of all primates and the vast majority of mammals.

Prepuce, or as an adjective, preputial, refers to two homologous structures of male and female genitals:

In some animals, the male penis possesses a muscle enabling retraction into the prepuce.

<span class="mw-page-title-main">Fibula (penile)</span> Ring fastened to the human penis

A penile fibula is foremost a ring, attached with a pin through the foreskin to fasten it above the glans penis. It was mainly used by ancient Roman culture, though it may have originated earlier. This ring type of fibula has been described akin to a "large modern safety pin". Its usage may have had several reasons, for example to avoid intercourse, to promote modesty or the belief that it helped preserve a man's voice. Some Jews also utilized fibulas to hide that they were circumcised. The word fibula could also be used in general in Rome to denote any type of covering of the penis for the sake of voice preservation or sexual abstinence, it was often used by masters on their slaves for this purpose. Fibulas were frequent subject of ridicule among satirists in Rome.

<span class="mw-page-title-main">Penile raphe</span> Line of tissue on the human penis

The penile raphe is a visible line or ridge of tissue that runs on the ventral (urethral) side of the human penis beginning from the base of the shaft and ending in the prepuce. The line is typically darker than the rest of the shaft skin, even though its shape and pigmentation may vary greatly among males. The penile raphe is part of a broader line in the male reproductive organs, that runs from the anus through the perineum and continues to the scrotum and penis, collectively referred to as median raphe. The penile raphe is homologous to the female labia minora.

References

  1. Fahmy, Mohamed A. Baky. "Prepuce." Rare Congenital Genitourinary Anomalies. Springer Berlin Heidelberg, 2015. 33-41.
  2. Edward C. Feldman (2004). Canine and feline endocrinology and reproduction. Elsevier Health Sciences. pp. 934–. ISBN   978-0-7216-9315-6. Archived from the original on 31 December 2013. Retrieved 25 April 2013.
  3. Horst Erich König; Hans-Georg Hans-Georg; H. Bragulla (2007). Veterinary Anatomy of Domestic Mammals: Textbook and Colour Atlas. Schattauer Verlag. ISBN   978-3-7945-2485-3. Archived from the original on 2016-05-11. Retrieved 2019-12-13.
  4. The behavior guide to African mammals: including hoofed mammals, carnivores, primates . University of California Press. 1991. pp.  116–. ISBN   978-0-520-08085-0 . Retrieved 25 April 2013. penile sheath OR penis sheath OR prepuce.
  5. "UQ researchers unlock another koala secret". Uq.edu.au. 2001-05-09. Archived from the original on 2013-05-12. Retrieved 2012-07-16.
  6. Elizabeth G. Crichton; Philip H. Krutzsch (12 June 2000). Reproductive Biology of Bats. Academic Press. pp. 104–. ISBN   978-0-08-054053-5.
  7. Sukumar, pp. 100–08.
  8. George B. Schaller (15 October 2009). The Serengeti Lion: A Study of Predator-Prey Relations. University of Chicago Press. pp. 329–. ISBN   978-0-226-73660-0. Archived from the original on 28 May 2013. Retrieved 10 February 2013.
  9. "The Stallion: Breeding Soundness Examination & Reproductive Anatomy". University of Wisconsin-Madison. Archived from the original on 2007-07-16. Retrieved 7 July 2007.
  10. Valerius Geist (1998). Deer of the World: Their Evolution, Behaviour and Ecology. Stackpole Books. ISBN   978-0-8117-0496-0. Archived from the original on 23 June 2016. Retrieved 11 May 2013.
  11. Fiona Reid (15 November 2006). Peterson Field Guide to Mammals of North America: Fourth Edition. Houghton Mifflin Harcourt. ISBN   978-0-547-34553-6. Archived from the original on 23 June 2016. Retrieved 11 May 2013.
  12. Maruniak, J. A., Claude Desjardins, and F. H. Bronson. "Adaptations for urinary marking in rodents: Prepuce length and morphology Archived 2018-07-20 at the Wayback Machine ." Journal of Reproduction and Fertility 44.3 (1975): 567-570.

Further reading