Biology:Teat

From HandWiki
Short description: Projection from mammary glands from which milk flows
Teats protruding from the udder of a cow
Part of a milking device that fits over the teats of a cow.

A teat is the projection from the mammary glands of mammals from which milk flows or is ejected for the purpose of feeding young.[1][2][3] In many mammals the teat projects from the udder. The number of teats varies by mammalian species and often corresponds to the average litter size for that animal.[4][5] In some cases, the teats of female animals are milked for the purpose of human consumption.

The quality of some domesticated animals is determined by the establishment of desired characteristics, such as teat size and placement.[6][7]

Number and positioning in animals

The number and positioning of mammary glands and teats varies widely among mammals. The protruding teats and accompanying glands can be located anywhere along the two milk lines. In general, most mammals develop mammary glands in pairs along these lines, with a number approximating the number of young typically birthed at a time. The number of teats varies from 2 (in elephants and anthropoids) to 18 (in pigs). Marsupials usually have 4 to 12 teats,[8] but the Virginia opossum has 13, one of the few mammals with an odd number.[9][10] The following table lists the number and position of teats and glands found in a range of mammals:

Species[11] Cranial teats
(thoracic)
Intermediate teats
(abdominal)
Caudal teats
(inguinal)
Total teats
Goat, sheep, horse
guinea pig
0 0 2 2
Polar bear 4 0 0 4
American black bear, Asian black bear, grizzly bear 4 0 2 6
Camel 0 0 4 4
Cattle 0 0 4 4
Cat 2 2 4 8
Dog 4 2 2 or 4 8 or 10
Mouse 6 0 4 10
Rat 6 2 4 12
Pig 4 4 4 12
Elephants, anthropoids (including humans) 2 0 0 2

Disease of teats

A number of diseases can affect the teats of cattle.[12]

Goats are also affected by diseases of the teats.[13]

Etymology

Teat is derived from the Old French or Dutch word, "tete" or the Greek word τιτθύς.[14] An alternative, but possibly not unrelated, would be the Welsh word "teth" or the Old English, "titt" which is still used as a slang term. The words "teat" and "tit" share a Germanic ancestor. The second of the two, tit, was inherited directly from Proto-Germanic, while the first entered English via Old French.[15][16]

See also

References

  1. "teat - Wiktionary". https://en.wiktionary.org/wiki/teat#English. 
  2. "Definition of TEAT". https://www.merriam-webster.com/dictionary/teat. 
  3. "teat - definition of teat in English - Oxford Dictionaries". https://en.oxforddictionaries.com/definition/teat. 
  4. Rowen D. Frandson; W. Lee Wilke; Anna Dee Fails (1 April 2013), Anatomy and Physiology of Farm Animals, John Wiley & Sons, pp. 449–451, ISBN 978-1-118-68601-0 
  5. "Mammalian Milk". http://www.earthlife.net/mammals/milk.html. 
  6. "Teat Structure Chart" (in en). American Boer Goat Association. http://abga.org/abga-education/teat-structure-chart/. 
  7. Blackburn, Lorrie. "More on Teats". The National Pygmy Goat Association. http://www.npga-pygmy.com/resources/conformation/teats.asp. 
  8. Julian Lombardi (6 December 2012). Comparative Vertebrate Reproduction. Springer Science & Business Media. ISBN 978-1-4615-4937-6. https://books.google.com/books?id=tXvjBwAAQBAJ&q=teats. 
  9. "With the Wild Things – Transcripts". Digitalcollections.fiu.edu. http://digitalcollections.fiu.edu/wild/transcripts/possums1.htm. 
  10. Stockard, Mary (2005) Raising Orphaned Baby Opossums. Alabama Wildlife Center.
  11. Cunningham, Merle; LaTour, Mickey A.; Acker, Duane (2005). Animal Science and Industry. Pearson Prentice Hall. ISBN 978-0-13-046256-5. 
  12. Ruegg, Pamela L.. "Diseases of Bovine Teats and Skin - Reproductive System". http://www.merckvetmanual.com/reproductive-system/udder-diseases/diseases-of-bovine-teats-and-skin. 
  13. "Mastitis and Ketosis: Health Problems of Lactating Does". http://www.tennesseemeatgoats.com/articles2/mastitisketosis.html. 
  14. Schrevelius' Greek Lexicon, Translated Into English, with Many New Words Added, Retrieved 11 August 2018
  15. Harper, Douglas (2001–2010). "teat". Online Etymological Dictionary. http://www.etymonline.com/index.php?term=teat. 
  16. Harper, Douglas (2001–2010). "tit (1)". Online Etymological Dictionary. http://www.etymonline.com/index.php?term=tit.