Merck Manual

Please confirm that you are a health care professional

honeypot link

Resident Flora


Manuals Staff

Last full review/revision Feb 2020 | Content last modified Oct 2020

A healthy animal lives in harmony with many microorganisms that establish themselves on or in the body. The microorganisms that usually live on or in a particular body site are called the resident flora (or microbiota). The resident flora at each site include several, or even several hundred, different types of microorganisms. Environmental factors such as diet or sanitary conditions influence what microorganisms make up an animal’s resident flora. The resident flora are beneficial, often protecting the body against other organisms that can cause disease. Under normal conditions, if the resident flora are disturbed, they promptly reestablish themselves.

Under certain conditions, microorganisms that are part of an animal’s resident flora may cause disease. Such conditions include the use of antibiotics or a weakened immune system. When antibiotics used to treat an infection kill a large proportion of the resident flora of the skin or intestine, other bacteria or fungi can multiply without being held in check.

Others also read
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Test your knowledge
Neoplasia of the Eye and Associated Structures
Squamous cell carcinoma is a common neoplasm in several species. Ocular squamous cell carcinoma is most common in animals with light pigmentation around the eyes, because sun exposure is one of several predisposing factors. This tumor is common in each of the following species EXCEPT:
Become a Pro at using our website 

Also of Interest

Become a Pro at using our website