bacterial load of raw milk

No.

Pasteurize.

If we need to refrigerate milk at home, how come we do not refrigerate the cow?

Doorman is right, pasteurize to get rid of bacteria.

Here is a study that used fractionation of the dairy product to compare counts of Mycobacterium avium paratuberculosis in milk, cream, curd, whey and colostrum. The mycobacterium was detectable in all of the fractions, however, 80-90 percent were found in the curd and 10-20 percent in the cream. Whey had the lowest count.

Another study also used centrifugation to recover the same mycobacterium which separated preferentially into the cream and solid fraction. The method was probably used because mycobacteria are especially small and therefore more difficult to detect. Something similar (but also using a soap) was used for detection of Listeria here.

You'll notice that the focus of these studies is not to produce a safe milk by separation from the cream - it is to detect a small amount of dangerous bacteria in a dairy product that is fresh and has no obvious sign of contamination. Remember that any bacteria in the dairy product will quickly multiply given time and favourable conditions for growth. Some are cold tolerant and will even grow in ice cream.. Therefore pasteurize, and enjoy your cream and curds as well as milk.