LORI.bovine

Cystic structures in the vagina

Keywords: vagina, bovine, Gartner's, Bartholin, Nabothian, minor, major, vestibular, mesonephric, duct, cervix, Skene

First, a reminder as to the location of the structures under discussion in this entry. The vagina in this context includes the cranial vagina and the vestibule of the vagina i.e. that segment caudal to the external urethral opening. The author has constructed the following drawing to illustrate the position of various vaginal structures.

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The structures discussed here bear the names of surgeons, gynecologists or anatomists: Thomas Bartholin (Bartholin's gland), Hermann Gärtner (the umlaut is usually omitted i.e Gartner; Gartner's ducts) and Martin Naboth (Nabothian glands). There is also brief mention of  the eponyn Skene's glands, named for Alexander Skene.

The image below shows two small Nabothian cysts in the mucosa of the external cervical os of a cow. A yellow margin has been drawn around them to emphasize their location. Nabothian cysts containing thick, tenacious mucus can be several times larger than those seen here; large enough to be palpable through the vaginal wall.

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Nabothian cysts also occur in water buffalo (Bubalus bubalus), humans and probably many other animals. In water buffalo they occurred at a frequency of approximately one percent in one study but in domestic cattle, the incidence is probably much lower.  In 35 years of examining large numbers of bovine tracts from slaughter plants, the author has seen fewer than a half a dozen Nabothian cysts.

The cervix has a large population of Nabothian mucus-secreting glands. They provide lubrication during coitus and a cervical seal during pregnancy. It is when the secretory ducts of these glands become occluded, that Nabothian cysts develop. The appearance and disappearance of these cysts in relation to the menstrual cycle in women suggests, not surprisingly, that they respond to variations in estrogens during the cycle. The same is probably true of cattle where copious amounts of mucus are produced by the cervical glands during estrus but little, and of a more tenacious nature, during the luteal phase.

Unless Nabothian cysts  are very large and impede copulation, sperm transport or even artificial insemination, their effect on fertility is insignificant.

Below: A drawing of cystic Gartner's ducts constructed by the author from several images and personal observations. In this regard, a high quality image of cystic Gartners ducts would be most welcome in this entry. If the reader has such an image (one that could be lent to this library) please contact the author (lofstedt@upei.ca).

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Albeit a minor point, this author suggests that the term "hydroptic" (< hydrops) may be more appropriate than "cystic" in this case. The former description is akin to the term hydropsalpinx; used for distension of the uterine tube. In the author's opinion, the term "cystic" is more reminiscent of a distended sphere or sphere-like structure than a tubular structure. A trivial matter to be sure.

Gartner's ducts are remnants of the mesonephric (Wolffian) ducts present in bi-potential early embryos. These ducts fail to develop into the deferent ducts in the absence androgens from testicles. Gartners ducts themselves do not appear to have a significant secretory function. However, as described in an investigation of the reproductive tracts of 70 cattle, Gartner's ducts are closely associated with, or joined to, partially developed glands at the caudal openings of Gartner's ducts where they entered the vagina. The occasional presence of minor vestibular glands at the base of Gartners ducts in cattle may explain why the ducts sometimes become distended when their openings into the vagina are occluded. Current knowledge suggests that these glands are analogous to the prostate gland in males. They are referred to as minor vestibular glands or in human literature, as Skene's glands or even female prostate glands.

Note: Alexander Skene's eponym is not used in veterinary literature, probably because the minor vestibular glands (Skene's glands) are poorly developed in most animals. In humans by contrast, Skene's glands are usually well developed and are thought to be important for lubrication during sexual intercourse.

In one study of over a 1000 bovine reproductive tracts cystic Gartner's ducts were present in approximately 1% of the samples in other words, cystic Gartner's ducts are not common. There are rare reports of grossly distended Gartner's ducts. In one case, a duct was distended to the diameter of a grape fruit.

In most cases, cystic Gartner's ducts do not interfere with reproduction

Some readers  may wonder why the openings of Gartners ducts are so seldom seen during per vagina examinations. This is explained by by the fact that the openings of Gartner's ducts are very small, almost invisible or in some cases, absent altogether. In three different studies reviewed by this author, there were substantial differences in the presence or absence (unilaterally or bilaterally) of openings to Gartners ducts in cows. In essence, their openings were present bilaterally in perhaps 50 to 70% of cows and a single left duct-opening was present more often than a single right duct-opening.

In the case of Nabothian cysts, and cystic conditions of Gartners ducts and Bartholin's glands it is often not known what caused the openings of these ducts or glands to become occluded. It is possible of course, that contraction of scar tissue may be responsible for this after local inflammation. However, the openings of these ducts or glands could also become occluded due to hyperkeratosis in cases of hypo-vitaminosis A. Certainly, a lack of vitamin A has been shown to cause vaginal hyperkeratinosis in mice.  Interestingly, reports of hyperkeratosis in the genital tract began to emerge after 1947 when chlorinated naphalene (used in petroleum products and wood preservatives at the time) was found in cattle feed.  Not surprisingly, Dr S.J. Roberts in his masterpiece "Veterinary obstetrics and genital diseases. Theriogenology" refers to a 1953 paper by his Cornell colleague Dr K. McEntee, stating that "....abnormalities of Gartner's ducts...are rather common in the cow".  Clorinated naphlalenes are no longer common in cattle feed and accordingly, cystic Gartners are no longer common either. One can surmise that chlorinated naphthalene would have has similar effects on other glandular structures in the vagina.

Bartholin's glands are referred to as the major vestibular glands.

Below, an image of the caudal portion of a cow's vagina, showing a cystic Bartholin's gland on the left and the openings of both left and right Gartner's ducts.

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Bartholin’s glands are anatomical analogs of bulbourethral glands (Cowper’s glands) in males. Their functions include lubrication and pheromone production. As seen above, they too, may become cystic, some cysts being as large as 10 cm in diameter. In one study of 102 cows, cysts were present in approximately 25% of the animals (higher than expected by this author from personal observations of slaughter plant specimens). Although a small number of cysts were present bilaterally in that study, most were unilateral and interestingly, mostly on the left side.

It is likely that cystic Bartholin's glands have little effect on reproductive efficiency unless (as has been reported) they become so large as to protrude from the vulva lips and become contaminated, predisposing the animal to vaginitis,

Selected references

Alam, M.G.S.and Rahman, A.  1979. Diseases of the genital tract of indigenous cows in Bangladesh Trop. Anita. Hlth Prod. 11:179-180

Bademkiran, S. et al. 2009. Unilateral Bartholin Gland Cyst in A Pregnant Heifer. F.Ü.Sağ.Bil.Vet.Derg. 23:61 - 63

Bland Sutton, J.  On the origon of certain cysts- ovarian, vaginal, sacral, lingual and tracheal. Journal of Anatomy and Physiology. Normal and pathological. 1886 Vol20. 439-442 (21 plates and several woodcuts).

Blazquez N.B. et al. 1987. Histology and histochemistry of the bovine reproductive tract
caudal to the cervix part I. The vestibule and associated glands. British Vet. J. 143:328-337

Blazquez N.B. et al. 1987. Histology and histochemistry of the bovine reproductive tract caudal to the cervix Part II. The vagina and associated structures. British Vet. J. 143: 337-343

Hatipoglu, F. 2002. An abattoir study of genital pathology in cows: II. Uterus, cervix and vagina
Revue. Med. Veterinaire t., 153: 93-100

Mägert, H. J. et al. 1995 cDNA sequence and expression pattern of the putative pheromone carrier aphrodisin. 92: 2091–2095.

Pande. M. et al 2011 Nabothian and endometrial cysts in a buffalo. Buffalo Bulletin. 30: 219-2

Pavone, L. M. et al 2009. Expression of Orexin A and Its Receptor 1 in the Vestibular Glands of the Cattle Genital Tract. The Anatomical Record 292:202–206

P.M. Summers, P.M. 1974. An abbatoir study of the genital pathology of cows
in Northern Australia. Australian Vet. J. 50: 403-406

Zaviacic, M.1. et al. 2000. Ultrastructure of the normal adult human female prostate gland (Skene's gland). Anat Embryol (Berl). 201:51-61