Weaning

Weaning is the process of gradually introducing an infant human or mammal to what will be its adult diet while withdrawing the supply of its mother's milk.

The process takes place only in mammals, as only mammals produce milk. The infant is considered to be fully weaned once it is no longer fed any breast milk (or bottled substitute).

Baby eating baby food
Baby eating baby food

Humans

How and when to wean a human infant is controversial. The American Academy of Pediatrics recommends feeding a baby only breast milk for the first six months of its life.[1] Many mothers find breastfeeding challenging, especially in modern times when many mothers have to return to work relatively soon after the birth of their child.

The American Academy of Pediatrics, the World Health Organization, the National Health Service Choices UK, and the National Health & Medical Research Council in Australia recommend waiting until 6 months to introduce baby food.[1][2][3] However, many baby food companies market their "stage 1" foods to children between 4 and 6 months old with the precaution that the food is meant to be consumed in addition to breast milk or formula and is just for "practice". These practice foods are generally soft and runny. Examples include mashed fruit and vegetables. Certain foods are recommended to be avoided. The United Kingdom's NHS recommends withholding foods including those "that contain wheat, gluten, nuts, peanuts, peanut products, seeds, liver, eggs, fish, shellfish, cows’ milk and soft or unpasteurised cheese" until a baby is six months old, as they may cause food allergies or make the baby ill.[4] However, recommendations such as these have been called into question by research that suggests early exposure to potential allergens does not increase the likelihood of allergies, and in some cases reduces it.[5]

In many cultures around the world, weaning progresses with the introduction of feeding the child food that has been prechewed by the parent along with continued breastfeed, a practice known as premastication.[6] The practice was important throughout human history in that it naturally gave a child a greatly improved protein source in addition to preventing iron deficiency.[7] The prechewing of food also gives the baby long-term immunological benefits through factors in the mother's saliva.[6] However, premasticated food from caregivers of lower socioeconomic status in areas of endemic diseases can result in the passing of the disease to the child.[8]

No matter what age baby food is introduced, it is generally a very messy affair, as young children do not have the coordination to eat "neatly". Coordination for using utensils properly and eating with dexterity takes years to develop. Many babies begin using utensils between 10 and 14 months, but most will not be able to feed themselves sufficiently well until about 2 or 3 years of age.

Weaning conflict

At this point, the mother tries to force the infant to cease nursing, while the infant attempts to force the mother to continue. From an evolutionary perspective, weaning conflict may be considered the result of the cost of continued nursing to the mother, perhaps in terms of reduced ability to raise future offspring, exceeding the benefits to the mother in terms of increased survival of the current infant.[9] This can come about because future offspring will be equally related to the mother as the current infant, but will share less than 100% of the current infant's genes. So, from the perspective of the mother's evolutionary fitness, it makes sense for her to cease nursing the current infant as soon as the cost to future offspring exceeds the benefit to the current infant.[9] But, assuming the current infant shares 50% of the future offspring's genes, from the perspective of the infant's own evolutionary fitness, it makes sense for the infant to continue nursing until the cost to future offspring exceeds twice the benefit to itself (perhaps less, depending on the number of potential future offspring).[9][10] Weaning conflict has been studied for a variety of mammal species, including primates and canines.[11][12][13]

Age

Lactancia en tandem 1
Breastfeeding in tandem

There are significant individual and cultural variations in regards to weaning.

Scientifically, one can ask various questions; some of the most straightforwardly empirical include:

  • At what age do children self-wean?
  • At what age do various societies normatively choose to wean?
  • In comparison with other animals, especially similar primates, by various measures.

As there are significant ranges and skew in these numbers (some infants are never nursed, or only nursed briefly, for instance), looking at the median (half-way mark) is more useful than looking at the average.[14]

Considering biological measures of maturity, notably investigated by Katherine Ann Dettwyler, yields a range of ages from 2 1/2 years to 7 years as the weaning age analogous to other primates – the "natural age of weaning".[14] This depends on the measure, for example: weaning in non-human primates is often associated with eruption of permanent molars (humans: 5 1/2 to 6 years); comparing duration of nursing to length of pregnancy (gestation time) yields a factor of about 6 in chimpanzees and gorillas (humans: 6×9 months = 54 months = 4 1/2 years); body weight may be compared to birth weight (quadrupling of birth weight yields about 2 1/2 to 3 1/2 years for humans; 1/3 of adult weight yields 5 to 7 years for humans); and similarly for other measures.

Other studies are possible, as in psychological factors. For example, Barbara Rogoff has noted, citing a 1953 study by Whiting & Child, that the most distressing time to wean a child is at 13–18 months. After this peak, weaning becomes progressively easier and less distressing for the child, with "older children frequently wean[ing] themselves."[15]

In other mammals

In science, mice are frequently used in laboratory experiments. When breeding laboratory mice in a controlled environment, the weaning is defined as the moment when the pups are transferred out of the mothers' cage. Weaning is recommended at 3 to 4 weeks after parturition.[16]

For pet carnivores such as dogs or cats, there are special puppy or kitten foods commercially available. Alternatively, if the pet owner feeds the parent animals home-made pet food, the young can be fed the same foods chopped into small pieces.

In cattle

Weaning in cattle can be done by many methods. Dairy calves are usually weaned off their mother at birth.[17] Beef calves are not usually weaned off their dams until the calves are between 8 and 10 months of age.[18] Before a calf is completely weaned off of milk, for both dairy and beef cattle, the calf must have developed a fully functioning rumen.[19] For beef cattle, there are many methods of weaning that are used. The use of these methods depends on farm management style, feed availability, condition and age of cow (dam), type of production and whether or not the calves are heifers.[18] Results vary between farms, and methods are still being researched as studies have shown contradicting results on stress levels of calves from different methods of weaning.

Traditionally beef calves are weaned by abrupt separation, where the calves are separated from their dams and have no contact with each other, or by fence line weaning where the dam and calf have contact over a fence line.[20] This has shown to cause high stress in both the dams and the calves.[20] Both the dams and the young express high vocalization, reduced feed intake, reduced rumination, and an increased amount of time searching for each other[21] as well as disrupting the social structure of the herd and of the calves.[18] There is evidence that calves can undergo a form of depression post weaning, and have the potential to undergo illness that may need to be treated.[21]

Two step weaning is a newly developed method used to wean off beef calves from their dams. With this method the calf is fitted with a nose flap that prevents suckling for a period of time, after which the calf is separated from the dam preventing contact.[22] The nose flap does not limit the calf from performing any behaviors other than suckling; they are still able to drink and graze normally.[21] Most research has shown that this method reduces the amount of stress that the calves endure. Studies show that prior to separation there is no change in feeding habits, social interaction to other members of the herd.[21] Once the nose flap is removed and the calves are separated from the dams, there has been data showing less vocalization, less pacing and spent more time eating than calves that were weaned on a more traditional method.[21]

Dairy calves are separated from their dam soon after they are born in most dairy operations. In some there is no contact between calf and cow for health related reasons, such as preventing Johne's disease. The main purpose of separating dairy cows from their calves to allow collection and selling of milk. The calves are then fed colostrum from the dam for the first few days, and then milk replacer.[23] Dairy calves do not have ab libitum milk like beef calves. By limiting the amount of milk the calves receive it caused the calves to consume more feed which leads to faster development of the rumen.[23] Dairy calves are usually weaned off milk early, usually at 4–8 weeks of age.[24]

In horses

Weaning in horses usually takes place when the foal is 4 to 5 months old,[25] as by this point the foal no longer needs nutrients beyond what the mare offers.[26] Prior to weaning the foal, there is usually a creep feeder set up to allow the foal to begin consuming feed that the mare cannot access.[26] There are two main approaches to weaning foals, abrupt and gradual weaning.[25] Abrupt weaning is when the mare and foal are separated,[25] usually without contact. Gradual weaning consists of the separating the mare and foal, but still with contact, but not enough contact that allows nursing to occur, and then after a period of time the mare and foal are separated not allowing contact, or, in some cases, sight of each other.[25] Foals that are weaned by the abrupt method have shown to have higher stressful behaviors displayed.[26] Weaning foals in groups for both methods can reduce stress in the foals.[26]

In dogs

With dogs the puppies are slowly weaned off their mother, slowly reducing the amount of milk and care that the mother is giving to them. It generally is started when the puppies are 3–4 weeks old, and usually continues until they are 7–8 weeks old. It is a gradual process that occurs over several weeks. By weaning the puppies slowly, it allows the mothers milk to dry up at a slow pace, making it less stressful for the mother.[27]

Naturally, in the wild, the mother will begin weaning off the puppies because the puppies will start developing teeth which will irritate the mother when the puppies are suckling. This causes her to continually leave the puppies for longer periods of time, causing them to gradually be weaned off their mother. Wild dogs will also regurgitate food to transition the puppies to a new diet.[28]

During this weaning process the puppies will learn from their litter-mates, and from their mother certain behaviors such as understanding dominance, and learning to reduce their biting habit and when to be submissive to others.[27]

While weaning the puppies should be fed a high quality diet that will be fed to them as they grow post weaning. It may be helpful to moisten the food with water or milk replacer for the first while. By feeding the puppies this it causes the puppies to reduce how much they rely on their mother for food.[27]

In rats

Rats that are raised in a laboratory, or are bred for selling purposes,[29] are usually weaned at the age of 3 weeks.[30] If the pups were left with their mother then weaning would not occur until they were older. This can have some health and behavioral benefits in the rats.[30] The main reason that pups are weaned at 3 weeks of age is because often the mother is pregnant again, especially in a laboratory setting or if owned by a rat breeder, and therefore the pups must be weaned off the mother before the next litter is born.[29] By doing this it will prevent trampling of the pups, as well as over crowding, which can easily, especially if the mother is being kept in a monogamous pairs.[30] Generally the pups are separated by sex when weaning occurs, but are never housed alone.[29] After weaning has begun, the pups should be fed a supplemented diet for at least a month, but can be done up to 13 weeks.[31]

In kittens

Weaning kittens involve transitioning the kittens from mother’s milk to solid food.[32] During weaning kittens gradually progress from dependence on a mother’s care to social independence. Ideally, weaning is handled entirely by the mother cat. However, if the kitten, for instance, is separated from its mother weaning may have to be done by someone.[33]

Twenty-four hours after birth, kittens can discriminate between their mothers teat and a foreign teat.[34] Studies indicate that kittens have different preferences when being weaned and this is based on specific prenatal and postnatal exposure to various flavours.[35] For example, kittens exposed to cheese flavor during pregnancy and the first week after birth oriented preferentially toward cheese-flavored chicken.[36] The weaning process normally begins when kittens are around four weeks old, and is usually completed when they reach 8–10 weeks. it is important to remember that abrupt removal from the mother cat can have a negative effect on the kitten’s health and socialization skills.[37] Weaning kittens should be done when the kittens reach 4 weeks old. They should be placed in a separate area for a few hours at a time to reduce their dependence on the mother’s milk and her overall presence. The kittens should be put in their own special area with a litter box, food and water bowls.[38]

See also

References

  1. ^ a b "Longer Breastfeeding Leads to Better Protection". American Academy of Pediatrics. 2010. Archived from the original on 2014-09-08. Retrieved 2012-02-26.
  2. ^ "Your baby's first solid foods". NHS Choices. Archived from the original on 2016-07-18. Retrieved 2016-07-15.
  3. ^ "Introducing solid food". Pregnancy, Birth & Baby. Archived from the original on 2016-07-07. Retrieved 2016-07-15.
  4. ^ "Solids: the first steps" Archived 2010-07-30 at the Wayback Machine. Retrieved 2010-06-28.
  5. ^ "The New Yorker". Archived from the original on 2011-04-05.
  6. ^ a b Pelto, Greta; Zhang, Yuanyuan; Habicht, Jean-Pierre (2010), "Premastication: the second arm of infant and young child feeding for health and survival?", Journal of Maternal and Child Nutrition, Blackwell Publishing Ltd, 6 (1): 4–18, doi:10.1111/j.1740-8709.2009.00200.x, PMID 20073131
  7. ^ Stoltzfus, Rebecca J. (2011), "Iron Interventions for Women and Children in Low-Income Countries", Journal of Nutrition, 141 (4): 756S–762S, doi:10.3945/jn.110.128793, PMID 21367936
  8. ^ Premasticating Food for Weaning African Infants: A Possible Vehicle for transmission of HIV, Elke R. Maritz, Martin Kidd, Mark F. Cotton Pediatrics Vol. 128 No. 3 September 1, 2011 "Archived copy". Archived from the original on 2011-09-24. Retrieved 2013-02-01.CS1 maint: Archived copy as title (link)
  9. ^ a b c Salmon, C.; Shackelford, T.K. (2008). Family Relationships: An Evolutionary Perspective. Oxford University Press. pp. 148–149. ISBN 978-0-19-532051-0.
  10. ^ "Parent-offspring conflict". Archived from the original on 2009-04-02. Retrieved 2009-09-23.
  11. ^ Trivers, R. (2002). Natural selection and social theory. Oxford University Press. pp. 124–126. ISBN 978-0-19-513062-1.
  12. ^ "Gorilla". National Primate Research Center, University of Wisconsin - Madison. Archived from the original on 2009-10-02. Retrieved 2009-09-23.
  13. ^ Packard, J.M., Mech, L.D. & Ream, R.R. "Weaning in an arctic wolf pack:behavior mechanisms" (PDF). pp. 1269–1275. Archived (PDF) from the original on 2009-10-01. Retrieved 2009-09-23.CS1 maint: Multiple names: authors list (link)
  14. ^ a b "A Natural Age of Weaning Archived 2012-03-30 at the Wayback Machine", by Katherine Ann Dettwyler, brief version of chapter "A Time to Wean" in Breastfeeding: Biocultural Perspectives, pp. 39–73, ed. Patricia Stuart-Macadam and Katherine A. Dettwyler, 1995, ISBN 978-0-202-01192-9
  15. ^ Rogoff, B. (2003). The Cultural Nature Of Human Development. Oxford University Press. pp. 64–65. ISBN 0-19-513133-9.
  16. ^ http://ko.cwru.edu/services/musfrming.html Archived November 24, 2010, at the Wayback Machine
  17. ^ "Early Weaning Strategies (Dairy Cattle Nutrition)". Dairy Cattle Nutrition (Penn State Extension). Archived from the original on 2016-11-27. Retrieved 2016-11-26.
  18. ^ a b c "Weaning beef calves". www.dpi.nsw.gov.au. 2007-09-13. Archived from the original on 2016-09-10. Retrieved 2016-11-26.
  19. ^ Filley, S. "Weaning Beef Calves" (PDF). Oregon State University. Archived (PDF) from the original on 2017-08-08.
  20. ^ a b "Weaning - Beef Cattle Research Council". www.beefresearch.ca. Archived from the original on 2016-08-07. Retrieved 2016-11-26.
  21. ^ a b c d e "BC SPCA". BCSPCA. Archived from the original on 2016-11-27. Retrieved 2016-11-26.
  22. ^ Enriquez, Ungerfeld, Quintans, Guidoni, Hotzel (2010). "The effects of alternative weaning methods on behaviour in beef calves". Livestock Science. 128: 20–27. doi:10.1016/j.livsci.2009.10.007.CS1 maint: Multiple names: authors list (link)
  23. ^ a b "AFTER THE CALF IS BORN". www.fao.org. Archived from the original on 2016-11-20. Retrieved 2016-11-26.
  24. ^ "Feeding Young Dairy Calves". The Merck Veterinary Manual. Archived from the original on 2016-11-27.
  25. ^ a b c d "Weaning Your Foal". asci.uvm.edu. Archived from the original on 2015-08-17. Retrieved 2016-11-26.
  26. ^ a b c d Freeman, David. "Weaning and Management of Weanling Horses" (PDF). Oklahoma Cooperative Extension Service. ANSI-3978. Archived (PDF) from the original on 2016-11-27.
  27. ^ a b c "Weaning Puppies: What to Do". WebMD. Archived from the original on 2016-11-29. Retrieved 2016-11-28.
  28. ^ "Breeding - Growing, Lactation, Weaning". Vetwest Animal Hospitals. Archived from the original on 2016-11-29. Retrieved 2016-11-28.
  29. ^ a b c "Rodent Breeding Colony Management – Rats » Research Committees » Boston University". www.bu.edu. Archived from the original on 2016-12-02. Retrieved 2016-12-01.
  30. ^ a b c "Breeding Guide: Birth to Weaning Figure 3". ratguide.com. Archived from the original on 2016-09-12. Retrieved 2016-12-01.
  31. ^ "National Fancy Rat Society". www.nfrs.org. Archived from the original on 2016-09-09. Retrieved 2016-12-01.
  32. ^ "Weaning Kittens: How and When | What to Feed a Kitten | Bottle Feeding Kittens | petMD". www.petmd.com. Archived from the original on 2017-04-07. Retrieved 2017-04-07.
  33. ^ "Weaning a Kitten from Mother's Milk to Solid Food". WebMD. Archived from the original on 2017-04-07. Retrieved 2017-04-07.
  34. ^ Ewer, R.F (1961). Further Observations On Suckling Behaviour in Kittens, Together With Some General Considerations of the Interrelations of Innate and Acquired Responses. south africa. pp. 247–260.
  35. ^ P.G. Hepper1, D.L. Wells1, S. Millsopp1, K. Kraehenbuehl2, S.A. Lyn3 and O. Mauroux (2012). "Prenatal and Early Sucking Influences on Dietary Preference in Newborn, Weaning, and Young Adult Cats" (PDF). Chem Senses. 37: 755–766. doi:10.1093/chemse/bjs062/2/bjs062.pdf (inactive 2018-06-06). Archived (PDF) from the original on 2017-04-07.CS1 maint: Multiple names: authors list (link)
  36. ^ Aure´lie Becques1, Claire Larose2, Patrick Gouat1 and Jessica Serra1 (2009). "Effects of Pre- and Postnatal Olfactogustatory Experience on EarlyPreferences at Birth and Dietary Selection at Weaning in Kittens" (PDF). Chem Senses. 35: 41–45. doi:10.1093/chemse/bjp080/2/bjp080.pdf (inactive 2018-06-06). Archived (PDF) from the original on 2017-04-07.CS1 maint: Multiple names: authors list (link)
  37. ^ Suzanne Hetts, PhD; Marsha L. Heinke, DVM; Daniel Q. Estep (2004). "Behavior wellness concepts or general veterinary practice" (PDF). JAVMA. 225: 4. Archived (PDF) from the original on 2017-04-07 – via ADMIN.CS1 maint: Multiple names: authors list (link)
  38. ^ PetPlace.com. "Weaning Kittens". Archived from the original on 2017-06-08. Retrieved 2017-04-07.
Al aḥqāf

Al-Aḥqāf (Arabic: ٱلْأَحْقَاف‎, "the sand dunes" or "the winding sand tracts") is the 46th chapter (surah) of the Qur'an with 35 verses (ayat). This is the seventh and last chapter starting with the letters ha-mim. It is one of the late Meccan chapters, except for verse 10 and possibly a few others which Muslims believe were revealed in Medina.

The chapter covers various topics: It warns against those who reject the Quran, and reassures those who believe; it instructs Muslims to be virtuous towards their parents; it tells of the Prophet Hud and the punishment that befell his people; and it advises Muhammad to be patient in delivering his message of Islam.

A passage in chapter 15, which talks about a child's gestation and weaning, became the basis by which some Islamic jurists determined that the minimum threshold of fetal viability in Islamic law would be about 25 weeks. The name of the chapter comes from verse 21, where Hud is said to have warned his people "by the sand dunes" (fi al-Ahqaf).

Baby-led weaning

Baby-led weaning (often also referred to as BLW) is a method of adding complementary foods to a baby's diet of breastmilk or formula. A method of food progression, BLW facilitates the development of age appropriate oral motor control while maintaining eating as a positive, interactive experience. Baby-led weaning allows babies to control their solid food consumption by "self-feeding" from the very beginning of their experiences with food. The term weaning should not be taken to imply giving up breastmilk or formula, but simply the introduction of foods other than breastmilk or formula.

Breastfeeding

Breastfeeding, also known as nursing, is the feeding of babies and young children with milk from a woman's breast. Health professionals recommend that breastfeeding begin within the first hour of a baby's life and continue as often and as much as the baby wants. During the first few weeks of life babies may nurse roughly every two to three hours, and the duration of a feeding is usually ten to fifteen minutes on each breast. Older children feed less often. Mothers may pump milk so that it can be used later when breastfeeding is not possible. Breastfeeding has a number of benefits to both mother and baby, which infant formula lacks.Deaths of an estimated 820,000 children under the age of five could be prevented globally every year with increased breastfeeding. Breastfeeding decreases the risk of respiratory tract infections and diarrhea, both in developing and developed countries. Other benefits include lower risks of asthma, food allergies, type 1 diabetes, and leukemia. Breastfeeding may also improve cognitive development and decrease the risk of obesity in adulthood. Mothers may feel pressure to breastfeed, but in the developed world children generally grow up normally when bottle fed.Benefits for the mother include less blood loss following delivery, better uterus shrinkage, and decreased postpartum depression. Breastfeeding delays the return of menstruation and fertility, a phenomenon known as lactational amenorrhea. Long term benefits for the mother include decreased risk of breast cancer, cardiovascular disease, and rheumatoid arthritis. Breastfeeding is less expensive than infant formula.Health organizations, including the World Health Organization (WHO), recommend breastfeeding exclusively for six months. This means that no other foods or drinks other than possibly vitamin D are typically given. After the introduction of foods at six months of age, recommendations include continued breastfeeding until one to two years of age or more. Globally about 38% of infants are only breastfed during their first six months of life. In the United States in 2015, 83% of women begin breastfeeding and 58% were still breastfeeding at 6 months, although only 25% exclusively. Medical conditions that do not allow breastfeeding are rare. Mothers who take certain recreational drugs and medications should not breastfeed. Smoking, limited amounts of alcohol, or coffee are not reasons to avoid breastfeeding.

Female factory

Female factories were based on British bridewells, prisons and workhouses. They were for women convicts transported to the penal colonies of New South Wales and Van Diemen's Land.

An estimated 9,000 convict women were in the 13 female factories, in the colonies of NSW and Van Diemen's Land. This spanned a period of 52 years -1804 to 1856. An estimated 1 in 5 to 1 in 7 Australians are related to these women. The factories were called factories because each was a site of production. The women produced spun wool and flax in all the factories. In the main factories other work was undertaken such as sewing, stocking knitting and straw plaiting. Hard labour included rock breaking and oakum picking.Women were sent to the female factories while awaiting assignment to a household or while awaiting childbirth or weaning or as punishment.

Foal

A foal is an equine up to one year old; this term is used mainly for horses. More specific terms are colt for a male foal and filly for a female foal, and are used until the horse is three or four. When the foal is nursing from its dam (mother), it may also be called a "suckling". After it has been weaned from its dam, it may be called a "weanling". When a mare is pregnant, she is said to be "in foal". When the mare gives birth, she is "foaling", and the impending birth is usually stated as "to foal". A newborn horse is "foaled".

After a horse is one year old, it is no longer a foal, and is a "yearling". There are no special age-related terms for young horses older than yearlings. When young horses reach breeding maturity, the terms change: a filly over three (four in horse racing) is called a mare, and a colt over three is called a stallion. A castrated male horse is called a gelding regardless of age; however, colloquially, the term "gelding colt" is sometimes used until a young gelding is three or four. (There is no specific term for a spayed mare other than a "spayed mare".)

Horses that mature at a small stature are called ponies and occasionally confused with foals. However, body proportions are very different. An adult pony can be ridden and put to work, but a foal, regardless of stature, is too young to be ridden or used as a working animal. Foals, whether they grow up to be horse or pony-sized, can be distinguished from adult horses by their extremely long legs and small, slim bodies. Their heads and eyes also exhibit juvenile characteristics. Although ponies exhibit some neoteny with the wide foreheads and small stature, their body proportions are similar to that of an adult horse. Pony foals are proportionally smaller than adults, but like horse foals, they are slimmer and have proportionally longer legs than their adult parents.

Graz tube weaning model

The Graz tube weaning model (German: Graz Sondenentwöhnung) is a method that supports parents, caregivers and professionals to help and empower medically fragile children with early and post-traumatic eating behavior disorders, particularly tube dependency.

Hamster

Hamsters are rodents (order Rodentia) belonging to the subfamily Cricetinae, which contains 18 species classified in seven genera. They have become established as popular small house pets. The best-known species of hamster is the golden or Syrian hamster (Mesocricetus auratus), which is the type most commonly kept as pets. Other hamster species commonly kept as pets are the three species of dwarf hamster, Campbell's dwarf hamster (Phodopus campbelli), the winter white dwarf hamster (Phodopus sungorus) and the Roborovski hamster (Phodopus roborovskii).

Hamsters are more crepuscular than nocturnal and, in the wild, remain underground during the day to avoid being caught by predators. They feed primarily on seeds, fruits, and vegetation, and will occasionally eat burrowing insects. Physically, they are stout-bodied with distinguishing features that include elongated cheek pouches extending to their shoulders, which they use to carry food back to their burrows, as well as a short tail and fur-covered feet.

Hawkinsinuria

Hawkinsinuria, is an autosomal dominant metabolic disorder affecting the metabolism of tyrosine. Normally, the breakdown of the amino acid tyrosine involves the conversion of 4-hydroxyphenylpyruvate to homogentisate by 4-Hydroxyphenylpyruvate dioxygenase. Complete deficiency of this enzyme would lead to tyrosinemia III. In rare cases, however, the enzyme is still able to produce the reactive intermediate 1,2-epoxyphenyl acetic acid, but is unable to convert this intermediate to homogentisate. The intermediate then spontaneously reacts with glutathione to form 2-L-cystein-S-yl-1,4-dihydroxy-cyclohex-5-en-1-yl acetic acid (hawkinsin).

Patients present with metabolic acidosis during the first year of life (can manifest with metabolic acidosis and growth arrest around the time of weaning off breast milk) which should be treated by a phenylalanine- and tyrosine-restricted diet. The tolerance toward these amino acids normalizes as the patients get older. Then only a chlorine-like smell of the urine indicates the presence of the condition, patients have a normal life and do not require treatment or a special diet.

The production of hawkinsin is the result of a gain-of-function mutation, inheritance of hawkinsinuria is therefore autosomal dominant (presence of a single mutated copy of the gene causes the condition). Most other inborn errors of metabolism are caused by loss-of-function mutations, and hence have recessive inheritance (condition occurs only if both copies are mutated).

Intermittent mandatory ventilation

Intermittent Mandatory Ventilation (IMV) refers to any mode of mechanical ventilation where a regular series of breaths are scheduled but the ventilator senses patient effort and reschedules mandatory breaths based on the calculated need of the patient. Similar to continuous mandatory ventilation in parameters set for the patients pressures and volumes but distinct in its ability to support a patient by either supporting their own effort or providing support when patient effort is not sensed. IMV is frequently paired with additional strategies to improve weaning from ventilator support or to improve cardiovascular stability in patients who may need full life support.

Kitten

A kitten is a juvenile cat. After being born, kittens are totally dependent on their mother for survival and they do not normally open their eyes until after seven to ten days. After about two weeks, kittens quickly develop and begin to explore the world outside the nest. After a further three to four weeks, they begin to eat solid food and grow adult teeth. Domestic kittens are highly social animals and usually enjoy human companionship.

Lactation suppression

Lactation suppression refers to the act of suppressing lactation by medication or other non pharmaceutical means. The breasts may become painful when engorged with milk if breastfeeding is ceased abruptly, or if never started. This may occur if a woman never initiates breastfeeding, or if she is weaning from breastfeeding abruptly. Historically women who did not plan to breastfeed were given diethylstilbestrol and other medications after birth to suppress lactation. However, its use was discontinued, and there are no medications currently approved for lactation suppression in the US and the UK.

Mammary gland

A mammary gland is an exocrine gland in humans and other mammals that produces milk to feed young offspring. Mammals get their name from the Latin word mamma, "breast". The mammary glands are arranged in organs such as the breasts in primates (for example, humans and chimpanzees), the udder in ruminants (for example, cows, goats, and deer), and the dugs of other animals (for example, dogs and cats). Lactorrhea, the occasional production of milk by the glands, can occur in any mammal, but in most mammals, lactation, the production of enough milk for nursing, occurs only in phenotypic females who have gestated in recent months or years. It is directed by hormonal guidance from sex steroids. In a few mammalian species, male lactation can occur. With humans male lactation can occur only under specific circumstances.

Mechanical ventilation

Mechanical ventilation, or assisted ventilation, is the medical term for artificial ventilation where mechanical means are used to assist or replace spontaneous breathing. This may involve a machine called a ventilator, or the breathing may be assisted manually by a suitably qualified professional, such as an anesthesiologist, respiratory therapist, or paramedic, by compressing a bag valve mask device.

Mechanical ventilation is termed "invasive" if it involves any instrument inside the trachea through the mouth, such as an endotracheal tube or the skin, such as a tracheostomy tube.

Face or nasal masks are used for non-invasive ventilation in appropriately selected conscious patients.

The two main types of mechanical ventilation include positive pressure ventilation where air (or another gas mix) is pushed into the lungs through the airways, and negative pressure ventilation where air is, in essence, sucked into the lungs by stimulating movement of the chest. Apart from these two main types there are many specific modes of mechanical ventilation, and their nomenclature has been revised over the decades as the technology has continually developed.

Nose ring (animal)

A nose ring is a ring made of metal designed to be installed through the nasal septum of pigs (to prevent them from rooting) as well as domestic cattle, usually bulls. In pigs, nose rings are alternatively pierced through the rim of the nose. Nose rings are often required for bulls when exhibited at agricultural shows. There is a clip-on ring design used for controlling and directing cattle for handling. Nose rings are used to encourage the weaning of young calves by discouraging them from suckling.

Oldfield mouse

This article is about the North American species Peromyscus polionotus, known as the "oldfield mouse". See Thomasomys for the South American genus also known as "Oldfield mice".

The oldfield mouse or beach mouse (Peromyscus polionotus) is a nocturnal species of rodent in the family Cricetidae. It is found in the southeastern United States on sandy beaches, in corn and cotton fields, and in hedge rows and open timber tracts. Coloration varies with geographic location; inland populations are generally fawn-colored, while coastal populations are lighter or white. The mouse eats seeds, fruits, and occasionally insects, and lives and raises its three to four young (at a time) in a simple burrow. Weaning occurs at 20–25 days, and females may mate at 30 days of age. Predators are those that prey on small mammals. One individual lived in captivity for about five years. The mouse is of least concern to conservationists because it is abundant and widespread, and no major threats exist for the species as a whole, but several subspecies with small distributions are endangered or even extinct.

Rapid shallow breathing index

The rapid shallow breathing index (RSBI) is a tool that is used in the weaning of mechanical ventilation on intensive care units. The RSBI is defined as the ratio of respiratory frequency to tidal volume (f/VT). People on a ventilator who cannot tolerate independent breathing tend to breathe rapidly (high frequency) and shallowly (low tidal volume), and will therefore have a high RSBI.

WUST

WUST (1120 kHz) is an AM radio station licensed to Washington, DC. Its transmitter is located in nearby Fairfax, Virginia. WUST broadcasts paid foreign language programming, including an English language news program from China Radio International and French language programming from Radio France International. WUST operates at 50,000 watts during the day but it must reduce power during early morning hours and go off the air during the night to protect the signal of KMOX in St. Louis, which is the dominant Class A station on 1120 AM.

WUST first signed on in 1947 as WBCC, licensed to the Washington, DC suburb of Bethesda, Maryland with 250 watts of power, broadcasting in the daytime only. It had been a rhythm and blues station. Its call letters came from its studio location at 1120 U Street, NW, later moving to 815 V Street NW, site of today's 9:30 Club.

During the 1950s, DJs Lord Fauntleroy Bandy and "Terrible" Thomas popularized R&B music with high school students, weaning them from Top 40. Part of the appeal of WUST was its location in the red light district of the time.During late August 1963, the ballroom of the WUST studio served as the operations headquarters for the August 28 March on Washington for Jobs and Freedom.On April 6, 2017, WUST filed an application for a Federal Communications Commission construction permit to remain on the air at night with 50 watts. The application was accepted for filing on April 12, 2017.New World Radio sold WUST to Herndon, Virginia-based Potomac Radio Group for $750,000 on September 18, 2018.

Weaning (TV series)

Weaning is a 2013 Chinese romance/family TV series starring Tong Liya and Lei Jiayin. While a love story at heart, the show also explores the Chinese issue of overprotective parents and overdependent children (some of whom need to be "weaned" in their 30s).

Witch's milk

Witch's milk or neonatal milk is milk secreted from the breasts of some newborn human infants of either sex. Neonatal milk secretion is considered a normal physiological occurrence and no treatment or testing is necessary. It is thought to be caused by a combination of the effects of maternal hormones before birth, prolactin, and growth hormone passed through breastfeeding and the postnatal pituitary and thyroid hormone surge in the infant.Breast milk production occurs in about 5% of newborns and can persist for two months though breast buds can persist into childhood. Witch's milk is more likely to be secreted by infants born at full term, and not by prematurely-born infants. The consistency of neonatal milk is estimated to be quite similar to maternal milk. Its production may be also be caused by certain medications. In extremely rare cases neonatal mastitis may develop but it is unclear if it is related to neonatal milk secretion.In some cultures the tradition of removing the milk ("milking") has been reported. This practice can prolong milk production and other problems can not be excluded. While breastfeeding may also contribute to prolonged milk production and breast enlargement, temporary, or permanent weaning is not recommended.In folklore, witch's milk was believed to be a source of nourishment for witches' familiar spirits. It was thought to be stolen from unwatched, sleeping infants. In other cultures expressing milk from the infant's breasts is supposed to contribute to a good breast shape in adulthood.Blood from the nipples is nearly always benign and frequently associated with duct ectasia; it should only be investigated when it is unilateral.

This page is based on a Wikipedia article written by authors (here).
Text is available under the CC BY-SA 3.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.