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Related to letdown: milk letdown




1. A decrease, decline, or relaxation, as of effort or energy.
2. A disappointment: The cancellation of the game was a real letdown.
3. The descent made by an aircraft in order to land.
4. A physiological response in lactating females, activated usually in response to sucking or crying by an infant, in which milk previously secreted into the alveoli of the breasts is released into the ducts that lead to the nipple.

milk letdown

, letdown
The ejection of a mother's milk from the alveoli of the breast into the mammary ducts and to the nipple.


1. the sudden flush of milk flow that occurs when the calf begins to suck or when milking commences in a properly prepared cow. Depends for its occurrence on the release of oxytocin from the pituitary gland in response to massage of the teats and udder. Environmental stimuli such as free electricity and fear or excitement can block the response. Is also sometimes absent in freshly calved cows but the cycle can be triggered by an injection of oxytocin.
2. a horse in overfat condition is said to be letdown; the converse of tuckedup.

milk letdown failure
occurs sporadically in all species. May be due to painful conditions of the teat or sharp teeth of sucker. Anxiety, as in maiden heifers, can be a cause. Other cases occur without obvious reason and respond dramatically to a single injection of oxytocin.
References in periodicals archive ?
ABC Head of Comedy Rick Kalowski said: From the moment The Letdowns pilot went out as part of our Comedy Showroom, it was clear the show had struck a chord with its brilliant blend of laughs and heartbreak the very stuff early parenthood is made of.
It does no good to have a pigment paste that is easy to manufacture and well-dispersed, but flocculates on letdown or otherwise hurts paint properties.
Lucidene[TM] 602 - hard film-forming polymer used as a letdown vehicle and overprint varnish.
Lucidene 370 - hard, non-film forming polymer used as a letdown vehicle for paper and paperboard applications.
Unfortunately, in many paint manufacturing cases, especially with high solids coatings, the letdown process or the letdown solution itself causes the pigment to flocculate.
For example, component or paste-letdown vehicle incompatibilities can be evaluated by placing droplets of two components or paste and letdown next to each other under a cover slip and observing their willingness to mix.
Comments: V48575-GV is a high solids, very fast setting, medium viscosity and yield QS letdown gel vehicle.
The only letdown was the group's choice of bland material and equally colorless presentation.
High pigment loadings (30 to 85%) provide high letdown ratios and maximum tinctorial strength.