Rarity and Breeding
The answer is that getting an albino animal in Planet Zoo is completely random. Every time you breed an animal, the offspring has a small chance to be albino. There is nothing you can really do to increase your chances of getting an albino except having more animals to breed.
If you get an albino animal, then you should use that for breeding. Its offspring will have a much higher chance of being an albino. If you get two albino animals of the same species, then these two can be used to breed lots of new albinos.
Some species do not have an albino variant. Check which species have an albino version, and breed them without stopping until you get one.
Albino Genes and Probability
The methods of obtaining albino animals in Planet Zoo is that it is completely random. If one parent is albino, there is a 30% chance. If there is an albino ancestor, even distant relatives, there is a slim chance. The further the albino ancestor, the lower the probability.
Keep breeding, keep introducing new animals to the gene pool, and eventually you may pair animals heterozygous for the albino trait and get an albino baby.
Sandbox Mode and Albinism
Can you get albino animals in sandbox mode Planet Zoo?
Getting an albino animal in sandbox mode in Planet Zoo is also random. As with the standard mode, if you have more animals you increase the odds of obtaining albinos, so breeding is key.
Understanding Albinism
How do animals become albino?
Albinism occurs randomly when animals inherit genes that interrupt melanin production. Melanin determines skin, fur, and eye color. Albinos lack pigmentation, appearing white or pink with reddish eyes. However, not all albino animals have red eyes.
An albino variant exists for some species. The albino gene is recessive, so two non-albinos may produce an albino offspring. With continuous diverse breeding, heterozygous pairings can yield albinos.
Albinism reduces survivability. Albinos lack camouflage from predators and UV protection. But albino animals can survive in nature.