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Natural Mating in Turkeys Karl E. Nestor Reproduction in turkeys is controlled by the length of daylight. In the wild, the increasing day lengths in the spring stimulate the body of turkeys to produce hormones that are required for the development of the reproduction organs of males and females and are responsible for the desire of turkeys to mate. The turkey is quite different from mammals as the reproduction organs of both males and females are within the body cavity. The testis produces sperm required for fertilization of the egg. The egg is produced by the ovary (normally only the left ovary develops in turkeys). The ovary produces the ovarian follicles that ultimately are the yolks of the egg. The cells involved in the production of a young poult (term for a young turkey) are located in the germinal disk located on the yolk. After mating, sperm are deposited in the oviduct and stored in crypts in the lower portion of the oviduct. They are periodically released and travel up the oviduct and fertilize the cells in the germinal disk near the upper portion of the oviduct (Infundibulum). The yolk travels down the oviduct and other parts of the egg (albumen, shell membranes, and shell) are added. Male and female turkeys differ in many aspects. Males are heavier than females and they develop spurs and beards (some hens develop beards too). The adult tom also differs from the adult hen in facial features. The fleshly part of the face and neck, termed caruncles, are better developed in toms than in hens. The fleshly appendage on the top of the head, termed snood, is larger in toms than in hens. The facial features are termed secondary sexually characteristics and toms can modify the color of the caruncles and length of the snood during sexual display. The sexes also differ in behavior. Courting behavior of toms consists of strutting in the presence of hens. Strutting is commonly accompanied by gobbling and other vocalizations. Sexually mature males (toms) inflate their crop, lower their wings so that the tips of the wing feathers touch the ground, elevate all body feathers so that they stand at right angles to the body, fan their tail feathers and bend back their neck so the neck and head form a hairpin turn and the back of the head touches the erected body feathers. At intervals, hissing sounds are made and the males walk for a few steps while dragging the tips of their primary wing feathers. The fanned tail may be turned toward the hen in an attempt to further impress her. Although females can strut, it is not a common practice. Strutting is most commonly done by adult toms, although an occasional poult has been observed strutting. Mating of the two sexes is without exception initiated by the female. They demonstrate a willingness to mate by assuming a sexual crouch in the immediate vicinity of the male. Females usually remain receptive until mated by the tom or until he is no longer in the vicinity. On occasion, the receptive female with an intense desire to mate will follow the male around until mating occurs. During the actual mating process, the female assumes the sexual crouch, the male walks on the back of the female (termed treading), and holds on by grasping the back of the neck of the female with his beak. Cloacal contact between the tom and hen is made by the hen raising her tail head and the tom lowing his tail head, semen containing sperm is deposited in the oviduct of the female. The tom then walks off the hen and the hen stands up and shakes her feathers. A completed mating usually results in the hen expressing a lack of desire to mate again. A hen displays an intense desire to mate just prior to reaching sexual maturity as measured by first egg and immediately upon termination of broody symptoms (the desire to set on eggs). The hen’s desire to mate is minimal during periods of high egg production. In the wild, turkeys mate and the hens lay a nest full of eggs, set on the eggs until they hatch, and then take care of their young until they are capable of taking care of themselves. When natural matings were used to reproduce turkeys commercially, the females were fitted with cloth saddles to protect the female from damage by the male. Up until about the mid 1950’s commercially grown turkeys were still reproduced via natural mating. In the 60’s and later, commercial turkeys got too big to mate naturally and an artificially mating technique developed in 1937 was used to reproduce all turkeys. Usually heritage strains of turkeys are still reproduced by natural mating as they are not selected for high body weight. Turkeys have a pecking order in which one bird is dominant and can peck all other birds in the flock without being pecked back. There is a second bird in the order that can peck all other birds except the most dominant one. This goes all the way to the bottom where there is a bird that can not peck any other bird. The pecking order is established early and stays rather static except if a bird is injured or gets sick. When several toms are placed with the hens, the most dominant toms will do most of the matings. In fact, if too many toms are used, the frequency of mating will actually be reduced because the toms will spend too much time interacting with each other. When natural mating was used for reproduction of commercial turkeys, quite often single tom pens would be used. The first mating of toms and hens is quite important for turkey fertility. The initial sperm that is deposited during the first mating quite often fertilizes the eggs for several weeks after the mating, even if additional matings occur. It is quite important that the first mating occurs near the time of sexual maturity of females both with natural matings and artificial inseminations. |