This is a bit tricky. Let me start with the first sentence:
Possible alternatives: "lasts", "days", "phase". Animal Sex Tube Zoo Sex Pony Horse Sex
Continuing this way for each word, ensuring that proper nouns are left as they are but included in the three options if possible, and all other words are given three synonyms. This is a bit tricky
Words to consider: "valuable", "insights", "biology", "welfare". Animal Sex Tube Zoo Sex Pony Horse Sex
"Breeding"
Horses and ponies procreate through a process called ‘natural service|natural service|natural service’, where a stallion (masculine horse) interbreeds with a mare.