Weaning
Encyclopedia
Weaning is the process of gradually introducing a mammal
infant
, either human or animal, to what will be its adult diet and 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 no longer receives any breast milk (or bottled substitute).
Soft, runny food such as mashed fruit and vegetables or premasticated
foods are introduced to babies in the early stages of weaning, as they do not have teeth and are unable to chew. Certain foods are recommended to be avoided, such as those containing nuts or high levels of gluten
, salt
, or sugar
. The United Kingdom's NHS recommends withholding nuts, eggs and shellfish until a baby is six months old, in order to reduce allergic reactions. 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 allergic reactions.
s. 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. But, assuming the current infant shares 50% of the future offsprings' 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). Weaning conflict has been studied for a variety of mammal species, including primate
s and canine
s.
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 .
For pet
carnivore
s 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.
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
infant
Infant
A newborn or baby is the very young offspring of a human or other mammal. A newborn is an infant who is within hours, days, or up to a few weeks from birth. In medical contexts, newborn or neonate refers to an infant in the first 28 days after birth...
, either human or animal, to what will be its adult diet and withdrawing the supply of its mother's milk
Milk
Milk is a white liquid produced by the mammary glands of mammals. It is the primary source of nutrition for young mammals before they are able to digest other types of food. Early-lactation milk contains colostrum, which carries the mother's antibodies to the baby and can reduce the risk of many...
.
The process takes place only in mammals, as only mammals produce milk. The infant is considered to be fully weaned once it no longer receives any breast milk (or bottled substitute).
Weaning in human infants
Solid food is gradually introduced to a baby's diet, alongside its previous diet of breast or formula milk, at around six months (though this varies slightly from child to child). Before this, a child's digestive system and kidneys are still developing and are not yet ready to deal with solid food.Soft, runny food such as mashed fruit and vegetables or premasticated
Premastication
Premastication or pre-chewing is the act of chewing food for the purpose of physically breaking it down in order to feed another that is incapable of masticating the food by themselves. This is often done by the mother or relatives of a baby to produce baby food capable of being consumed by the...
foods are introduced to babies in the early stages of weaning, as they do not have teeth and are unable to chew. Certain foods are recommended to be avoided, such as those containing nuts or high levels of gluten
Gluten
Gluten is a protein composite found in foods processed from wheat and related grain species, including barley and rye...
, salt
Salt
In chemistry, salts are ionic compounds that result from the neutralization reaction of an acid and a base. They are composed of cations and anions so that the product is electrically neutral...
, or sugar
Sugar
Sugar is a class of edible crystalline carbohydrates, mainly sucrose, lactose, and fructose, characterized by a sweet flavor.Sucrose in its refined form primarily comes from sugar cane and sugar beet...
. The United Kingdom's NHS recommends withholding nuts, eggs and shellfish until a baby is six months old, in order to reduce allergic reactions. 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 allergic reactions.
Weaning conflict
Weaning conflict occurs when the mother wishes to stop nursing but the infant wishes to continue. 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. 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 geneGene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
s. 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. But, assuming the current infant shares 50% of the future offsprings' 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). Weaning conflict has been studied for a variety of mammal species, including primate
Primate
A primate is a mammal of the order Primates , which contains prosimians and simians. Primates arose from ancestors that lived in the trees of tropical forests; many primate characteristics represent adaptations to life in this challenging three-dimensional environment...
s and canine
Dog
The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...
s.
Cultural variations in age at time of weaning
The age at which children are normatively weaned can vary significantly between cultures, "from 6 months to 5 1/2 years". There is often a cultural expectation in the United States that children be weaned early, and there have been scientific studies performed to validate this expectation. However, as Barbara Rogoff has noted, citing a 1953 study by Whiting & Child, 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."Weaning in other mammals
In science, miceMICE
-Fiction:*Mice , alien species in The Hitchhiker's Guide to the Galaxy*The Mice -Acronyms:* "Meetings, Incentives, Conferencing, Exhibitions", facilities terminology for events...
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 .
For pet
Pet
A pet is a household animal kept for companionship and a person's enjoyment, as opposed to wild animals or to livestock, laboratory animals, working animals or sport animals, which are kept for economic or productive reasons. The most popular pets are noted for their loyal or playful...
carnivore
Carnivore
A carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of animal tissue, whether through predation or scavenging...
s 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.
See also
- BreastfeedingBreastfeedingBreastfeeding is the feeding of an infant or young child with breast milk directly from female human breasts rather than from a baby bottle or other container. Babies have a sucking reflex that enables them to suck and swallow milk. It is recommended that mothers breastfeed for six months or...
- Baby-led weaning
- Baby foodBaby foodBaby food is any food, other than breastmilk or infant formula, that is made specifically for infants, roughly between the ages of four to six months to 2 years. The food comes in multiple varieties and tastes, can be produced by many manufacturers, or may be table food that the rest of the family...
- LactationLactationLactation describes the secretion of milk from the mammary glands and the period of time that a mother lactates to feed her young. The process occurs in all female mammals, however it predates mammals. In humans the process of feeding milk is called breastfeeding or nursing...
- Male lactationMale lactationMale lactation in zoology means production of milk from mammary glands in the presence of physiological stimuli connected with nursing infants. It is well documented in the Dayak fruit bat.The term male lactation is not used in human medicine...
- ProlactinProlactinProlactin also known as luteotropic hormone is a protein that in humans is encoded by the PRL gene.Prolactin is a peptide hormone discovered by Henry Friesen...