They are all separate genes so he can be homozygous for everything. He is a Perleno so that in and of itself is Homozygous cream on Black bass. He can be also Homozygous black and Homozygous Tab. He could also be Homozygous Agouti but it would be hard to see on a Perleno.
Past all that the sire will give one set of genes to the foal so Unless the mare some some of all of these genes will determine if the foal is Homozygous or not. He can not be homozygous based only on his sire. He needs the same gene from his dam also.
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