Frankly, my response would be "so what?"
All of the animals we breed are kept in captivity and abused in various ways until they are killed, wild animals would be unaffected, so what is the net impact on the earth? If anything, a positive one.
Deforestation, which cattle ranching is a large driver of, is causing 100s or 1000s of species to go extinction every year, way more than might be lost if we all stopped eating farmed animals.
I would say… we are not eating animals because they are roaming around freely, we breed them into existence to fatten up and eat or take their produce ie eggs and milk. As the demand to eat them and their produce declines so will the need to breed them into existence. Many farmers are turning their animals over to sanctuaries and many have been rescued and are in sanctuaries so they are not going to go extinct. We don’t eat rhinos, giraffes and elephants which are also not extinct.
I would relate that to how dogs are bred in other countries just for food. If a dog is bred and raised with the knowledge that it will be food, does that make this alright? Or is this not alright solely because in our society we view dogs as pets? It would be better to have no animal suffering and no animals bred than to have billions tortured and killed every year.
Hey, make your dad watch Earthling Ed videos on Youtube, trust me.
I am utterly confused by your dad’s logic. Animals don’t exist because WE breed them. Ummm, more of them would exist if we didn’t KILL them.
Are horses extinct, because people stopped using them as the primary mode of transportation, like they did back in the day, before the advent of mechanical vehicles? No, they’re not extinct. People just stopped breeding them for that purpose enmass. Have him look up Chicken breeds, there are many types still around, because of hobby breeders. Chickens, are not just all white, like the commercial hens & "broiler" chickens. There are Cream Leghorns, Buff Orpingtons, Silkies, Sultans, etc. Chickens, pigs, & cattle, can make great companion animals. However, it would not be a bad thing, for commercial chicken, cattle, & pig breeds to go extinct, because they were selected to have unnatural traits, like overdeveloped muscle mass, which creates extreme disabilities, if the animals are allowed to grow up, because they can’t support their own weight, & thereby suffer terribly. This is why "broiler" chicken are killed at only 8 weeks (2 months) old, & some pigs are killed at only 6 months old.