There are times when the weather will not work well for animal photography. Either the sun is to high in the sky, the weather is bad or the light is completely flat.
My favorite pet photos are done outside with the pet being active. Nevertheless, many owners want a classic pet photo done in the studio.
I am partial to black backgrounds but white also works well
Many designers love white backgrounds because that allows them to separate the animal from the background.
Many owners like to have props added to the set; I find small animals work better with props and large animals work better without.