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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 ?
Touring nonstop behind The Beautiful Letdown, Switchfoot had no choice but to write and record the bulk of the follow-up album on the road.
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.
Custom formulations are available for pellet dimensions, letdown ratios, and FDA and CONEG certification as well as recycling requirements.
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.
Polyflam flame-retardant concentrates include Polyflam RS 425C3 for 3:1 letdown in high-heat, high-impact PS to give UL 94V-0; and highly stable Polyflam RCP 770 for LDPE and HDPE film with letdown ratios from 10:1 to 4:1.
Comments: V48575-GV is a high solids, very fast setting, medium viscosity and yield QS letdown gel vehicle.
Comments: Surkovar 8051 is a high viscosity high gel letdown varnish for flushes.
Flame-retardant concentrates in PS, ABS, and polyolefin bases supplied for varying letdown ratios.
New high-strength color concentrates are said to provide extra-low letdown ratios in an unusually broad array of plastics, including polyolefins, nylon, ABS, PET, PBT, PBT/ABS blends, and ABS/PC blends.
And although the Bruins are sure to have some rustiness, Bruins junior tailback Maurice Drew said he doesn't expect any letdown in preparing for the Dec.
The colors used, medium dark pewter and very dark pewter, have concentrate letdown ratios of 50:1, providing cost savings over typical ratios of 25:1.