rescue dog

noun
1
a dog that has been rescued after being treated badly
سگ نجات‌یافته, سگ بی‌پناه, سگ بی‌خانمان
2
a dog that is trained to take part in rescue operations
سگ نجات, سگ امداد, سگ نجاتگر, سگ امدادگر
Training a search and rescue dog can take as long as three years.