Regurgitation (digestion)

Humans

Regurgitation can be voluntary or involuntary for humans. It can occur alongside gastroesophageal reflux disease (GERD), acid reflux and some anatomical abnormalities. In infants however, regurgitation – or spitting up – is quite common, with 67% of 4-month-old infants spitting up more than once per day. Chronic, involuntary regurgitation of ingesta following ingestion, commonly known as rumination syndrome, is a rare and often misdiagnosed disorder.

Some people are able to regurgitate without using any external stimulation or drug, by means of muscle control. Practitioners of yoga have also been known to do this. Professional regurgitators perfect the ability to such a degree as to be able to exploit it as entertainment.

Birds

For birds that transport food to their mates and/or their young over long distances — especially seabirds — it is impractical to carry food in their bills because of the risk that it would be stolen by other birds, such as frigatebirds, skuas and gulls. Such birds often employ a regurgitative feeding strategy. Many species of gulls have an orange to red spot near the end of the bill (called a "subterminal spot") that the chicks peck in order to stimulate regurgitation.

All of the Suliformes employ a regurgitative strategy to feed their young. In some species — such as the blue-footed booby, masked booby, and the Nazca booby — a brood hierarchy exists, in which the older chick is fed before the younger, subordinate chick. In times when food is scarce, siblicide may occur, where the dominant chick kills its younger sibling in order to sequester all of the resources of the parents. Penguins chicks are fed regurgitated food by both parents. Researchers found that the practice may potentially cause metabolic alkalosis in certain penguins.

Some birds, such as fulmars, employ regurgitation as a defense when threatened.

Other animals

Ruminants regurgitate their food as a normal part of digestion. During their idle time, they chew the regurgitated food (cud) and swallow it again, which increases digestibility by reducing particle size.

Honey is produced by a process of regurgitation by honey bees, which is stored in the beehive as a primary food source.

File:Bubbling fly.jpg|Bubbling fly File:Fly December 2007-20.jpg|Bubbling fly (Calliphora vicina) File:Pollenia spec - bubble blowing.ogv|Pollenia sp. blowing bubbles (video, 3m 1s)

References

References

1. Nelson, R.W. and C. G. Couto. Small Animal Internal Medicine, 4th ed. 2009.
2. (2001). "Social behaviour in farm animals". CABI Publishing.
3. (2005). "Birds: the inside story". Struik Publishers.
4. (April 2006). "Childhood functional gastrointestinal disorders: neonate/toddler". Gastroenterology.
5. Chari, C. T. K. (1973) '"Regurgitation, mediumship and yoga." ''Journal of the Society for Physical Research'' 47, 757, 156
6. "Stevie Starr, Professional Regurgitator". The Museum of Hoaxes.
7. Price, Haydn. (2007). "Chris Needs:Like It Is". Y Lolfa Cyf.
8. Drummond, Hugh. (1986). "Parent-Offspring Cooperation in the Blue-footed Booby (Sula nebouxii): Social Roles in Infanticidal Brood Reduction". Behavioral Ecology and Sociobiology.
9. (2013-01-01). "The different breeding strategies of penguins: A review". Comptes Rendus Biologies.
10. Janes, Donald N.. (1997). "Osmoregulation by Adélie Penguin Chicks on the Antarctic Peninsula". The Auk.
11. (2013). "Metabolic alkalosis due to feeding chicks in breeding Adélie penguins Pygoscelis adeliae under natural conditions". Physiological and Biochemical Zoology.