intermediate Reproduction
Allantois---An fetal membrane which contributes to the formation of the umbilical cord and placenta. Also, the allantochorion refers to the membrane formed
Amnion---The intermost placental membrane surroungind the embryo which contains fluids that bathe the embryo
Ampulla---An enlargement or dilation of the passageway; such as the innermost portion of the vas deferens in some male species, which is one of the accessory sex glands
Androgen---A hormone associated with development of secondary sex characteristics
Caruncles---Disc-like area of the uterine endometrial lining which with the fetal cotyledons form a strong connection known as the placentome
Castration---Removal of permanent alteration of the testicles of a male animal
Cells of Leydig---Interstitial cells of the testicle which produce the male sex hormone of androgens
Cervix---Constricted neck like structure located between the vagina and uterine body
Chorion---Outermost placental membrane which makes contact with the maternal uterine endometrial lining
Conception---Union of ovum and sperm; formation of the zygote Corpus albican---Term to denote tiny scars which remain after complete regression of earlier luteum
Corpus luteum---Active tissue which develops on the ovary at the site where an ovum has been shed. If conception does not occur, the tissue gradually disappears. If conception does not occur, the tissue becomes functional, producing progesterone
Cortex---Outer portion of an organ, such as ovary of kidney Cotyledon---Cup-shaped structure; area of the fetal chorion which connect with the uterine caruncles of the maternal host
Cowpers gland(s)---The paired accessory male sex glands posterior to the prostrate and on each side of the urethra
Cremaster muscle---Muscle which suspends the testicles and contracts or relaxes to enhance temperature regulation
Cryptorchid---A male animal where one or hoth of the testicles remained in the body cavity and did not descend into the scrotum during embryonic development, or by time of birth
Embryo---The developing young, during pregnancy, from soon after zygote formation to placentation (fetal stage)
Endometrium---the inner layer of the uterine wall and body Epididymis---A tortuous tube of considerable length leading form the testicle to the vas deferens. The principle site of sperm storage and maturation
Estrous Cycle---Physological events occurring in the reproductive system of a domesticated farm female animal between one estrus period and another; about 17 days in sheep; 22 days in cattle, swine and horses
Estrus---The time when a female is in heat and will breed readily. Also called estrus period
ET---Embryo transfer. Most commonly done with cattle, a 5-6 day old embryo from an elite female is transferred to one of the uterine horns of a recipient female, both horns if two embryos are transferred.
Fetus---The prenatal animal after fetal membranes (placenta) becomes functional; beyond the embryo state
Follicle (ovarian) ---The growth which appears on the surface of the ovary late in the estrous cycle and which contains the developing ovum
Follicle-stimulating hormone---A hormone produced by the pituitary gland that promotes growth of hormone ovarian follicles in the female and sperm in the male
Gestation period---The duration of pregnancy GnRH---Gonadotropin-releasing hormone; controls the release two of hormones from the pituitary, follicle stimulating hormone and luteinizing hormone
Gonad---Testis of a male or ovary of a female; organ which produces sex cells
Hypothalamus---Portion of brain involved in release of certain hormones; also aids in regulation of appetite and body temperature
ICSH---Intersitial-cell-stimulating hormone in the male. Synonymous with the term LH, a hormone produced in the pituitary that stimulates testis production of testosterone
Infundibulum---A funnel-shaped passageway such as the innermost portion of the oviduct of the hen
Intact---Term sometimes used to denote a male animal that has been castrated
Isthmus---A term denoting the relatively short section of the birds reproductive tract where the shell membranes are produced creating the shape of the egg
Luteinizing hormone---A hormone produced by the pituitary gland that causes rupture of ovarian follicles (ovulation) in the female and secretion of testosterone in the male
Medulla---The inner portion of a body organ Myometrium---The muscular wall of the uterus Oogenesis---Process of formation and development of ova Ovary---Female sex organ which produces ova after sexual maturity
Oviduct---Tube leading from each horn of the uterus to the corresponding ovary
Pampiniform plexus---Arrangement of veins about the testicle that aid temperature regulation of the testicles
Placenta---A structure in mammals that provide exchange of nutrients and waste materials between the maternal and fetal system
Polyestrous---Refers to animals which have several estrous cycles per year
Postpartum---After birth Pregnancy---The period of conception to birth Prenatal---Prior to birth Prostaglandin---Certain substances of the body; involved in bringing about regression of the corpus luteum
Prostate gland---A gland that surrounds a portion of the neck of the bladder and the urethra in the male
Puberty---The age when an animal is physiologically mature enough to be capable of sexual reproduction
Scrotum---Sac-like extension from the abdominal cavity of a male that contains the testicles
Semen---A mixture of spermatozoa and fluids from the accessory sex glands; the ejaculate
Seminal vesicles---Paired glands attached to the urethra near the bladder in the male, which produce fluids to carry and nourish the sperm
Seminiferous tubules---Tubular structures within the testicles where spermatozoa are produced
Spayed---Ovaries have been removed or oviducts leading to the uterus have been severed; to render the female sterile
Sperm---The male sex cell, produced by the testicle, and carrying a sample half of the genes of the male
Spermatic cord---Area between testicles and body which includes the vas deferens, and blood, lymphatic, and nerve supply to the testicles
Spermatogenesis---Productions of spermatozoa within the seminiferous tubules of the testicle
Testicle---Male sex organ which produces sperm after sexual maturity
Tunica dartos---Elastic tissue and muscle fibers within the scrotum that contract and relax to aid in temperature regulation of the testicles
Urethra---Portion of urinary tract that carries urine from the bladder; also in males, provides passage for semen ejaculate
Uterus---The female reproductive organ in which an embryo and fetus develops
Zygote---The diploid cell resulting from the union of haploid female and male gametes