Dogs can tell by smell if food is spoiled or not

How exactly do dogs know what is or isn’t safe to eat?
Dogs can generally tell by the smell, if the food is spoiled or not. If you try to feed bad food to a dog bad they will try to bury it. When they can’t tell if something is bad or not, via smell, they eat it and then throw it up if it’s bad and then they won’t eat it again.

My dog’s hind legs shake after exercising, but recently they have been shaking while she is at rest. She seems to feel fine otherwise. What could be causing the shaking in her legs?
One explanation may be this: with canine hip dysplasia, there may be muscle wasting in the hind legs, which explains the trembling that your dog experiences in the hind legs. Canine hip dysplasia is an orthopaedic disease in which an abnormal formation of the hip leads to looseness in the hip joints, causing cartilage damage. Progressive arthritis can result, and when it does, it can be crippling. Hip dysplasia is most common among German shepherds, rotweillers, labrador retrievers, golden retrievers, mastiffs, and Saint Bernards.

How many babies can a rabbit have at once?
Female rabbits generally have anywhere from two-10 babies each litter — or more! The babies are born blind and helpless and are taken care of and nursed in the delicately fur-lined nest prepared by their mother. Rabbits usually produce several litters every year.

My guinea pig’s feet are red and swollen. I know it’s not from a dirty cage because mine is always clean. What could be the problem?
Do you have a wire bottom on your cage? If so, then this could be the cause. Use soft bedding.
 
For how many years do guinea pigs live?
If you take good care of them they live upto about five to six years.