The reproductive system of male
poultry is comprised of a paired testes, epididymis, vasa deferentia and phallus.
The testis is pale yellow in colour and
elliptical in shape. The left testis may be larger than the right depending on
the species but both are functional. In contrast, there are no disparities in
the weight of the right and left testis in broiler breeder cocks. In seasonal
breeding birds, the testes attain 500 folds increase during the breeding season
when compared to those on the non
breeding season. The paired testes unlike in some mammalian species are located
inside the body cavity, and in poultry sperm remain active at the internal body
temperature which is detrimental to the survival of sperm in mammalian species.
In poultry, the testes are located anterior to the cranial lobe of the kidneys.
They are suspended to the body wall via the mesorchium and are covered by the
tunica albuginea and tunica vaginalis.
Each testis is a collection of anastomosing seminiferous tubules, with
associated interstitial tissue covered by a connective tissue capsule. Each
testis is linked to an epididymal duct via vasa deferentia that enters into the
cloaca and the rudimentary copulatory organ.
Keywords: Poultry, cock, genital system, anatomy, physiology
Poultry include all domesticated birds that are kept by man
with the aim producing meat and eggs. These bird species include chicken,
followed by turkey and quails. Other domesticated birds include ducks, guinea
fowl, geese, emu and ostrich 1.
However, apart from the domesticated avian species, studies have also been
carried out in many non-domesticated avian species, of which many exhibits reproductive patterns similar to those
of domesticated species.
importance of poultry products has resulted in numerous studies on poultry with
the major aim of enhancing product output. Genetic and reproductive physiology
has attracted enormous attention in poultry production 2. Unequivocally, an
understanding of the genetic potential, anatomy,
and physiology of poultry reproduction is of paramount importance to enhanced
product output (eggs and meat). Therefore, this chapter focuses on the male reproductive system of poultry and other
related bird species.
The male genital system of poultry is comprised of a pair
of testes (elliptical shaped and light yellow in colour) located close to the cephalic side of the kidneys. Each
testis is joined to epididymal duct through a deferent duct that enters the
cloaca. In the bird, spermatozoa remain
viable within the body temperature unlike in the mammal where sperm is not
viable at body temperature. This is the main reason the testes in man and other
mammalian species are located outside the scrotal sac. There is also a
copulatory organ called phallus which exists
in some poultry species and helps in the introduction of sperm to the female
reproductive tract of the hen. Accessory sex glands found in poultry include
the para cloacal vascular bodies, dorsal
proctodeal and lymphatic folds 3. The prostate, vesicular and Cowper’s glands
are absent in birds 1.