in-and-in

American  

[in-uhnd-in, -uhn-] / ˈɪn əndˈɪn, -ən- /

adverb

1. repeatedly within the same family, strain, etc..

   to breed stock in-and-in.

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in-and-in British  

adjective

1. (of breeding) carried out repeatedly among closely related individuals of the same species to eliminate or intensify certain characteristics

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Etymology

Origin of in-and-in

First recorded in 1620–30

Example Sentences

In the latter case breeding in-and-in is usually found to result in decided and rapid deterioration.

From The Principles of Breeding or, Glimpses at the Physiological Laws involved in the Reproduction and Improvement of Domestic Animals by Goodale, S. L.

Many of them are miserably poor; their flocks are reduced and deteriorated from disease and in-and-in breeding; their wagons are battered and dilapidated; they themselves look degraded and sunken and miserable.

From Tales of South Africa by Bryden, H.A.

Time flies, but sin breeds in-and-in,   And a father's grief is stern; Robin is dead, and a distant kin   Now calls himself Kildearn.

From Wilson's Tales of the Borders and of Scotland, Volume XXIV. by Leighton, Alexander

The changes which can be rung on three distinct strains of blood, without in-and-in breeding close enough to be attended with any considerable danger, are innumerable.

From Sheep, Swine, and Poultry Embracing the History and Varieties of Each; The Best Modes of Breeding; Their Feeding and Management; Together with etc. by Jennings, Robert

The two principles to be held in mind were, "Breed from the best," and "Breed in-and-in," with a cautious and occasional introduction of new strains.

From Studies in the Psychology of Sex, Volume 6 Sex in Relation to Society by Ellis, Havelock