Placenta Flashcards
Placenta
6 layers of tissues that can separate mother from offspring
Placenta
Maternal tissues
Blood vessel endothelium
Connective tissue
Epithelium of endometrium
Placenta
Fetal tissue
Chorion
Connective tissue
Blood vessel endothelium
Epitherlial-Chorial Placenta
maternal epithelium of the endometrium is in contact with the fetal chorion - No erosion of the epithelium
Sow, Mare
Have all 6 layers of hte tissue intact throughout pregnancy
Cattle, Sheep (modified epithelial-chorial AKA Syndesmo-chorial)
Endothelial-Chorial Placenta
Maternal blood vessel endothelium is in contact with fetal chorion - the uterine epithelium is eroded over sites of contact with the chorion
2 layers of tissue (epithelium and connective tissue of endometrium) have been removed at fetal-maternal contact sites
Dogs, Cats, and Other
Hemochorial Placenta
Maternal blood is in direct contact with the fetal chorion
3 layers of tissue have been removed at fetal-maternal contact sites
Primates, rats, mice, guinea pigs
Hemoendothelial
Rabbit
5 layers of tissue have been removed at fetal-maternal contact sites
Epithelium and connective tissue of the endometrium, maternal blood vessel endothelium, placental chorion, and placental connective tissue
Chorionic Villous Pattern
Porcine
Diffuse
Chorionic Villous Pattern
Equine
Diffuse, microcotyledonary
Chorionic Villous Pattern
Bovine, Ovine, Caprine
Cotyledonary
Caruncle → maternal
Cotyledon → fetal
Chorionic Villous Pattern
Zonary
Canine, Feline
Chorionic Villous Pattern
Discoid
Primates, Rodents
Male reproductive Tract
Consists of testicles and secondary sex organs
Epididymis, vas deferens, and penis - transport sperm from the testicle to the female reproductive tract
Ampulla - dilation in vas deferens that pools sperm during ejaculation
Three accessory sex glands: Seminal vesicles, porstate and bulbourethral gland
Testicle functions
produce spermatozoa
Produce testosterone
Testicle location
outside the body cavity in the scrotum (many mammals)
Essential for normal sperm formation since this occurs only at a temperature several degrees below normal body temperature
Pampiniform Plexus
found in the neck of the scrotum and serves as important thermoregulatory function
Complex venous netwrok that surrounds the testicular artery and functions as a countercurrent heat exchanger to reduce testicular temperature
Seminiferous tubules
made up of sertoli cells and layers of germ cells
Who has what accessory sex gland?
Bull, Stallion, Boar, Dog, Tom
Seminal vesicle, Prostate, Bulbourethral gland
Penis
Copulatory organ - deposits semen inot vagina or cervix/uterus
Some species have a fibroelastic penis, some have a very vascular penis and some have a bone in the penis
Species with an os penis tend to acheive an erection only after intromission has occurred
Chromosomal Abnormalities
XXX syndrome, XXXY syndrome, XO syndrome are occasionally ientified in animals
These animals often appear normal and are only identified if they are anestrous or fail to conceive offspring
Intersexes
mismatch of chromosomal - gonadal - phenotypic sex
Includes: hermaphrodites, pseudohermaphrodites, and freemartins
Intersexes are more common in goats than in other species
Hermaphrodite
Both ovarian and testicular tissue are present
The amount of testicular tissue present determin the extent of masculinization of the internal and external genitalia
Genetically-linked trait and both parents and all siblings should be remvoed from the breeding population
