Oestrus cycle is present in

The correct answer is Dog

Explanation:

• Several cyclical changes in the activities of ovaries, accessory ducts, hormones occur during the reproductive phase in the females of placental mammals.
• Such changes in the non-primates like cows, sheep, dogs etc., is called the Oestrus cycle.
• In primates like monkeys, humans, apes, it is called the Menstrual cycle.
• In the Oestrus cycle, the endometrium is reabsorbed into the body whereas in the Menstrual cycle the endometrium is shed off in each cycle.