**1. Introduction**

Artificial insemination (AI) is the manual transfer of semen into the female's vagina. Basically it is a two step procedure: first, collecting semen from the male [1]; and second, inseminating the semen into the female [2]. In poultry, depending on the objectives and goals of the farm or laboratory, there may be intervening steps such as semen dilution, storage, and evaluation.

Artificial insemination is practiced extensively with commercial turkeys. This is primarily the result of selective breeding for a heavier and broader-breasted commercial turkey and the consequent inability of toms to consistently transfer semen to the hen at copulation. The broiler industry has not adapted AI to the extent of the turkey industry but it is occasionally used in pedigree lines and in regions where labor is relatively cheap.

To grasp the magnitude of AI in the turkey industry compared to that of livestock, a hypo‐ thetical flock of 500 breeder hens inseminated with 100 μL of diluted semen (1:1) twice the week before the onset of egg production and once weekly thereafter for the 24 wk of egg production would entail 13,000 inseminations using 650 mL of semen. It should be apparent with these numbers, semen collection and hen inseminations are labor intensive as each male and female must be handled each week.

Looking back over the use of AI in the turkey industry one can safely say that in the 1960s, weekly inseminations were based on semen volume per dose using undiluted semen. In the 1970s and early 1980s, breeder farms began to dilute semen and inseminate a known number of sperm per dose. In the mid-1980s through the 1990s, hens were initially inseminated a week before the onset of lay and inseminations were performed with a known number of 'viable' sperm. Currently, while inseminating before the onset of egg production remains widely practiced, most companies, but not all [3], have gone back to inseminating a known volume of semen or number of sperm per dose, in the 1970s and 1980s.

© 2013 Bakst and Dymond; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

In the following chapter we will review the basics of AI and fertility evaluation in poultry. To better appreciate the biological basis of these techniques, an overview of the reproductive biology of poultry is provided. Detailed descriptions of techniques for the collection, evalua‐ tion, dilution, and storage of poultry semen are available in a recent publication by Bakst and Long [4]. Earlier comprehensive reviews include Lake and Stewart [5], Bakst and Wishart [6], and Bakst and Cecil [7].

is a fibrous reticulum about 2 μm thick. At ovulation, only the inner PL envelops the ovum. While there is no corpus luteum formation in birds, the thecal layers and the granulosa of the post-ovulatory follicle (POF) produce prostaglandins [12] and progesterone, respectively [13-16] then regress over the next 72 hr. The POF has a pocket like appearance after ovulation (Figure 1). On the surface of the inner PL overlying the germinal disc (GD), which is a 3.5 mm di‐ ameter disc of white yolk containing the haploid pronucleus and associated organelles, are sperm receptors. Sperm bind to the receptors overlying the GD, hydrolyze a path through the inner PL, and are incorporated into the ovum. Polyspermy is normal in birds but only one sperm in apposition to the female pronucleus undergoes nuclear decondensation and initiates synga‐

Artificial Insemination in Poultry http://dx.doi.org/10.5772/54918 177

**Figure 1.** The ovary and oviduct of a turkey hen in egg production occupy much of the abdominal cavity. The ovarian follicular hierarchy consisting of ovarian follicles at various stages of develop (7 maturing follicles visible in this photo‐ graph) is observed. The largest follicle, F1 follicle is the next to ovulate. The ovum ovulated about 10 hr earlier has accrued albumen in the magnum (m), a shell membrane in the isthmus, and is observed in the uterus (ut) undergoing shell formation. Its post-ovulatory follicular sheath (POF) appears as an open pocket. The vagina (distal to the uterus

The mature oviduct consists of five anatomically and functionally distinct segments (Figures 1 and 2): the infundibulum, which secretes an albumen-like product that forms the outer PL and prevents pathological polyspermy; the magnum, responsible for deposition of the

and not visible) is embedded in connective tissue and enveloped by the abdominal fat pad.

**2.2. Oviduct**

my, the reconstitution of the diploid number of chromosomes.
