Clones are not always gonna be an exact stamp of the animal they are cloned from...genotypically they are as close as you can possibly make one and should produce about the same. But phenotypically there are a lot of things that can be variables. Undoubtedly they are not all gonna be carried by the same cow so there are differences in development in utero, they arent all gonna be born under the exact same climatic situation so that will cause some difference, other things can also affect development...did one get sick and not the other, did they all eat the same thing, did they all eat as well...a lot of things influence phenotype, thus they arent all gonna look the same.