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Dictionary: estrus

 estrus / oestrus [ZOOL.]   der Östrus Pl.: die Östrus  - Zeit, in der Weibchen paarungsbereit sind   

estrus / oestrus [ZOOL.]   die Brunst Pl.: die Brünste

Dictionary: estrous

 abnormal estrous cycle [MED.]

abnormal oestrous cycle [MED.]      die Zyklusstörung Pl.: die Zyklusstörungen

Dictionary: brünstig

 Adjektive / Adverbien

 in heat  hauptsächlich (Amer.) [ZOOL.]      brünstig

in rut [ZOOL.]            brünstig

on heat  hauptsächlich (Brit.) [ZOOL.]      brünstig ...

Dictionary: Brunst*

Substantive

 ... estrus   / oestrus [ZOOL.]      die Brunst Pl.: die Brünste ...

https://www.collinsdictionary.com/dictionary/...

 estral in American English

(ˈestrəl)

adjective

pertaining to or involving the estrus ...

https://www.merriam-webster.com/dictionary/estral

 estral

variant of estrous

https://www.merriam-webster.com/dictionary/estrous

 estrous

adjective

es•trous ˈe-strəs

1   : of, relating to, or characteristic of estrus

2   : being in heat ...

https://www.collinsdictionary.com/dictionary/...

 estrous in American English

(ˈɛstrəs ; British; usually ˈistrəs )

adjective

of, or having the characteristics of, estrus ...

https://www.wordreference.com/definition/estral

 WordReference Random House Unabridged Dictionary of American English © 2023

estral

es•tral (es′trəl), adj.

   Physiology, Zoologyestrous.

   estr(us) + -al1

 ... oes•trus (es′trəs, ē′strəs), n.

   Zoology, Physiologyestrus.

   Greek oîstros gadfly, sting, madness

   Latin      1690–1700 ...

https://www.britannica.com/animal/dog/Reprodu...

 ...  The female may be receptive a day or two past the time when she would still be fertile. In order to be sure that the breeding is taking place at the optimum time, vaginal smears and blood tests can be done by a veterinarian beginning before estrus and through the estral phase. ...