my boxer got very slow

Question
all of the sadden my boxer got very slow. It looks like his system wants to closed down. He is only 7 and he was very energetic. Now maybe cause my sister left for a month he got depressed. i dont know. He dont want to eat, he lost weight and i trying mixing his food with some beef together,but nothing works. he walks very slow and the other day he was sleeping standing up. oh boy i notice also some white liquid dripping from his private part i dont know wht do to. PLEASE ANY SUGGESTIONS???

VERY MUCH APPRECIATED!!!!

Answer
Take your dog to the vet immediately. Any change in behavior to this extent, particularly eating should be seen as an emergency situation. Dogs do not show pain, nor changes in behavior due to illness until it is usually unbearable for them. Take your dog in NOW
Diane