幼犬和成犬通常是因接触到受感染的狗或野生动物的呼吸道分泌物而感染。

Puppies and dogs usually become infected through airborne exposure to the virus contained in respiratory secretions of an infected dog or wild animal.

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所有的狗都有可能感染犬瘟，但是四个月内的幼犬和没有注射过犬瘟疫苗的狗最易感染。

All dogs are at risk but puppies younger than four months old and dogs that have not been vaccinated against canine distemper are at increased risk of acquiring the disease.

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凡参加比赛之狗只必须体健及年满五个月以上，未满五个月之幼犬及怀春雌犬恕不招待。

All participating dogs must be at least 5 months old and in good health. No admission for puppies under 5 months old or bitches in season.

youdao

凡参加比赛之狗只必须体健及年满五个月以上，未满五个月之幼犬及怀春雌犬恕不招待。

All participating dogs must be at least 5 months old and in good health. No admission for puppies under 5 months old or bitches in season.

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