3Role of the male Produce ample amounts of viable sperm Willing and able to deliver semen (containing sperm)to femaleto AI
4Anatomy of MALE Paired TESTES Epididimyis Vas deferens Penis Scrotum Accessory Sex Glands
5Scrotum Testes descend from near kidney at or near birth failure: monorchid or chryptorchidMaintains temp 4-8° cooler than body
6Temp regulation in testes External Cremaster musclecontracts when cold, relaxes when warmtunica dartos (smooth muscles in skin)contract when coldpampiniform plexusheat exchanger in blood above testicleesp. stallion & boar
7The major species differences are related to which accessory sex glands are present and the structure of the penis.
8Spermatogenesis occurs within the seminiferous tubules of the testes under the metablic and hormonal support of sustentacular and interstitial cells (Sertoli’s cells).Sperm are stored and mature in the epididymes until resorption or ejaculation.
9Sperm are produced continually in great numbers Bull = 5 BILLION sperm per ejaculateRegulated by FSHCells of Leydig secrete testosteroneRegulated by LH
10Secretions of the accessory glands contribute to the formation of the semen. The penis contains vascular and connective tissue specializations to produce erection which facilitates intromission.
11The mammalian male reproductive tract consists of the testes, a duct system, and related glands.
12Testes & epididymisSperm are produced in the testis and mature in the epididymis.
13Ductus deferans (vas deferens) The ductus deferens (vas deferens) propel sperm to the urethraduring ejaculation.
31Sustenticular cellsThe outlines of sustentacular cells are not distinct. Maturingspermatozoa are found embedded, head first, in the sustentacularcells, which provide mechanical support, protection and possiblynutrition for the developing spermatozoa.
34Factors affecting sperm production Sexual maturityHeredityUnderfeedingNutrients like Vitamin A, E, proteinTemperatureTestis sizeAbnormalities
35Male ReviewSpermatogenesis occurs in the seminiferous tubules of the testes.Sustentacular and interstitial cells aid the development of spermatogonia into spermatozoa with a nuclear head, mitochondria filled midpiece and a microtubule tail.
36Sperm are stored and mature as they move through the head, body and tail of the epididymis and into the ductus deferens.Seminal fluid is formed by the addition of nutrients, buffers and lubricants from the accessory sex glands(e.g. vesicular, bulbourethral, prostate and ampulla.
37There is variation among species as to which glands are present. The penis may contain an os penis in addition to vascular sinuses, (corpus spongiosum and cavernosum) to produce erection.The urethra is also shared by the urinary tract.