Different animals take different time to decompose. Although some animals decompose quickly, their decomposing smell normally prevails the atmosphere for longer than expected. Knowing the duration that it takes for an animal to decompose will you the idea of idea of where to dispose the animal and how. To avoid inconveniencing yourself with the bad smell of the decomposing animal, make sure that you dispose it away from your home and wrap it in nylons. Conditions like snow, ice, and cold surfaces delay the decomposing process, therefore, they should be avoided.
An adult raccoon, an old one to be specific, takes a long time to decompose. Its body is known to be hard for the decomposition-causing factors to degrade it completely within a short time. Its skin is known to hardly absorb moisture which further delays its decomposition. Its inner parts spoil during the first few days, and the maggots starts infiltrating the body of a raccoon after a week. This is when its smell starts to be felt in the environment after its inner structures have been exposed by the maggots. Although its flesh might get decomposed completely after one month, its bones take up to a year for them to get degraded completely.
Rats are small creatures, but they can cause a lot of inconvenience when they are disposed near people's residence due to their bad smell. Their smell is known to persist for long after they decompose hence they should be disposed away from homes. When they decompose, the flesh and the bones turns into soil, nothing remains. The average time that rats take to decompose is three to four weeks depending on the area where they are disposed.
Animals like bats and rodents take long to decompose if they have lived for more than one year because their bones and tendons tend to be extremely hard. Bats and rodents take at least three weeks to decompose, but their smell might remain around for more than four days before the place in which they are disposed retains fresh air again. When you poison rats in your house, they could die in the hidden spaces of your home making them to decompose there and yield a very bad smell that will make your stay very uncomfortable.
The bottom line is that there is no specific known duration that an animal takes to decompose. Some huge animals are known to take even a year while others take only a week. The only caution people should take is to ensure that they dig holes, wrap the animal and burry it to avoid smell. If you can't burry it, then you should go and throw it miles away from your home and other people's homes so that it decomposes without spreading any bad smell to the people around. If you don't know how long an animal takes to decompose, just make sure that you throw it far away from your home to avoid any inconveniencing factors when it starts decomposing.