Here's the thing: the math usually doesn't work out in your favor. Here's an example.
Manatees
Sell for: 57,000
Breeding cost: 34,200
Breeding Success Rate: 49%
If I do 100 breedings I should get 49 baby manatees, so:
profit: 49 x 57,000 = 2,793,000
cost: 100 x 34,200 = 3,420,000
I've lost half a million; each breeding effort has cost me $6,270. And that's with breeding rates fully loaded, which means I can tack 30% on to the base breeding rate. (Only possible with the love zoo; otherwise +20 is the best you can do with a breeding habitat & watering hole.)
Let's do another: Cougars
Sell for: 450,000
Breeding Cost: 210,000
Breeding %: 43%
100 breedings
43 x 450,000 = 19,350,000
100 x 210,000 = 21 mil
You're out around 1.5 million; each breeding effort costs $16,500.
Can you ever profit off breeding?
Yes! Impalas are profitable as long as you have the love zoo.
Sell for: $210,000
Breeding cost: $82,000
Breeding %: 43%
100 breedings
Profit: 43 x 210,000 = 9,030,000
Cost: 100 x 82,000 = 8,200,000
profit 83,000 = 8,300 / breeding effort
Your formula: (sell price * breeding chance) - breeding cost = avg profit per breed
Your breeding chances: base chance + 40% (assuming love zoo and all equipment)
So, for impalas, I Googled: (210,000 * 43%) - 82,000
and got 8300.
Got any other profitable breeders? Share 'em!
Moorish Idols are uber profitable
(1,350,000 * 49%) - 580,000 = 81,500 profit
Let's look at the rest of the aquarium animals:
Sea Bunny: (2,100,000 * 43%) - 1,090,000 = -187,000
Belugas: (1,500,000 * 42%) - 670,000 = -40,000
Clownfish (4,875 * 47%) - 2,275 = 16 (lol)
Surgeonfish (375,000 * 46%) - 245,000 = -72,500
So the Moorish Idols are the only ones (that I personally have at least two of) that turn a profit.
Serengeti collection breeding costs
Impalas: (210,000 * 43%) - 82,000 = 8300.
Lions: (sell * 45%) - 15000
Leopards: (sell * 43%) - 16500
Flamingo: (21,000 * 45%) - 7000 = 2450
Hippos: (12,000 * 50%) - 8000 = -2000
Meerkats: (7500 * 45%) - 2500 = 875
Hyenas: (105,000 * 52%) - 89000 = -34,400
Black Rhinos: (sell * 45%) - 8000
African Elephants: (sell * 45%) - 600
African Wild Dogs: (sell * 43%) - breed
Cheetah: (sell * 46%) - 1950
Bat-Eared Fox: (sell * 43%) - breed
Caracal: (sell * 43%) - breed
Honey Badger: (sell * 43%) - breed
Nile Crocodile: (sell * 45%) - 500
Pangolin: (sell * 43%) - breed