Chapter 5

Reproductive processes must work properly for new animals to be produced. You need to know about the reproductive organs of animals and their functions to breed animals. The primary reproductive organ of the female is the ovary. The ovary produces female gametes, or sex cells that can unite with other sex cells. It is a mature sex cell capable of a union that produces an individual organism. The primary reproductive organ of the male is the testicle. Testicles produce male gametes or sperm. Two testicles are held externally in the scrotum of mammals and internally in the body cavity of male poultry and fish. Chapter 5 Introduction to Livestock and Companion Animals2

Reproduction involves a series of events that must be properly timed. Chapter 5 Introduction to Livestock and Companion Animals3 Puberty is the time at which animals reach a level of sexual development that makes them capable of reproduction. Fertilization is the union of a sperm and an egg. Gestation is the period of pregnancy. Parturition is the process of giving birth. Lactation is the production of milk. Incubation is the development of a new animal in the fertile egg of egg-laying species. Spawning is the release of eggs by a female fish and the subsequent fertilization by the male.

The use of artificial insemination (AI) today is more common than natural service in some species, such as dairy cattle and turkeys. Chapter 5 Introduction to Livestock and Companion Animals4 Artificial insemination is placing semen in the female reproductive tract by artificial techniques. Sexed semen has been prepared to produce all male or all female offspring. Estrous synchronization is bringing a group of animals into heat simultaneously to help schedule breeding and birthing. Embryo transfer is moving embryos from one female (donor) to the reproductive tract of another female (recipient). Cloning is the production of one or more exact genetic copies of an animal. Genetic engineering is removing, modifying, or adding genes to DNA.

Reproduction is the process by which offspring are produced. Animals naturally reproduce sexually. Reproductive efficiency is important to animal producers. Animals must breed and regularly produce offspring. Male and female animals have distinctive reproductive organs and systems. Reproductive development goes through several phases. New technology, such as AI, is used in reproduction. People must consider the ethics of the newer technology. Chapter 5 Introduction to Livestock and Companion Animals5