NAVLE（北美执业兽医考题）Day 791

Q1:A dog presents to your clinic with tenesmus and swelling near the anus as seen in the image. On examination, there is a fluctuant swelling lateral to the anus, and on rectal exam, you note lateral dilatation of the rectum. Which of the following is the most common signalment for dogs presenting with this problem?一只狗由于里急后重和如下图的肛门周围肿胀前来就诊。体格检查时你发现其肛门周围存在有波动性的肿胀部位，直肠检查时你还发现直肠侧向的扩张。以下哪项是患有此类疾病的狗的特征描述？[图片]