Repro Path Flashcards
compare chromosomal versus gonadal sex determination STAR
gonadal:
-everyone bipotential gonads during development/no default state
-ovaries and testes are gene-directed processes!
chromosomal:
female: XX; no SRY gene
male: XY; SRY gene, encodes for testis determining factor that makes mullerian inhibitory substance, which urges primordial gonad to become a testis
describe phenotypical sex determination STAR
hormonal secretion causes development of secondary sexual characteristics
-internal and external genitalia
what can go wrong with sex determination?
- chromosomal abnormalities
-abnormal number and/or mixture of sex chromosomes - gonadal abnormalities
-failure of effective signal to primitive and undifferentiated gonads - phenotypic abnormalities:
-message did not get through to ensure development of mesonephric vs paramesonephric duct
describe Turner syndrome
- a chromosome is missing!
-need 2 X’s to make all mediators in females, so can’t do that - common in mares
-ovaries are hypoplastic, tract is rudimentary
describe mosaic’s versus chimeras STAR
- mosaicism: occurs when there are 2 or more genetically different cell lines present originating from a single zygote
- chimerism: occurs when there are 2 or more genetically different cells lines present originating from 2 or more zygotes (freemartin)
describe klinefelter’s syndrome STAR
- polysomy: more than one X chromosome isn present
-XXY karyotype or more complex - occurs in stallions, bulls, boars, dogs
- cats: males with tricolor, tortoiseshell, or calico coat types
- also leads to testicular hypoplasia
- MALE CALICO CATS ARE USUALLY MOSAICS AND INFERTILE
describe intersex
- associated with gonadal dysgenesis and a female phenotype
- true hermaphrodite has to have both gonads (ovotestis) = RARE
- male pseudohermaphrodites COMMON
-clitoral hyperplasia
-androgen sensitivity syndrome: inability of tissue to respond to androgens
-5alpha-reductase deficiency: converts testosterone into DHT; feminized or ambiguous ext genitals with a functional testis
-SRY-positive but downstream gene dysregulation: mutation in genes downstream to SRY signaling; testes may form but fail to produce significant testosterone; external genitalia is female
-persistent mullerian duct syndrome: results from AMH mutations or its receptor, leads to persistence of mullerian duct structures (uterus and oviducts) alongside male gonads
describe developmental ovary conditions
- agenesis: RARE
-can be uni or bilateral - hypoplasia:
-XXX and X_ in mares and XXX in cows
-swedish highland cattle: autosomal recessive trait - ovarian remnant syndrome:
-2 different ovaries on each side by splitting during development or complete new ovary formation
-classic history of spayed female in heat or stump pyometra
describe developmental uterus, vagina, vulva conditions
- segmental aplasia: can happen at any portion of repro tubular organs
- imperforate hymen: blocks the flow of secretions and can lead to fluid accumulations or infections
-failure of fusion of caudal part of tube, causing double cervix
where can cysts occur?
not just ovaries!
intraovarian, periovarian, uterine, vaginal, vestibular
describe peri (para) ovarian cysts STAR
EQUINE!!
- an embryonic (wolffian duct) remnant becomes cystic, blocks egg from reaching oviduct
-oocyte released by ovulation but cyst may block ovulation fossa and the ovum pick up by uterine tube
describe ovarian tumors
- epithelium: adenoma/adenocarcinoma
-most common in dogs - carcinomatosis
describe ovarian sex cord tumors
- granulosa cell tumors, thecomas, luetomas, and sustentacular tumors
-granulosa cell tumors: common in cows and horses, usually benign but can be malignant in cats and dogs; on histopath will see follicle-like structures with granulosa cells surrounding eosinophilic material (Carl-Exner bodies); MAY produce testosterone and can get really big in horses
- frequently produce hormones
- generally unilateral and benign
describe teratomas
- germ cell derived neoplasm
- often have bits of bone or liver or other tissue all mixed in together
describe uterine adenocarcinomas STAR
- particularly common in older rabbits
- malignant and metastasize often!!
-come from epithelial cells
describe leiomyomas STAR
- benign form of smooth muscle neoplasia
- usually solitary, but can be multiples
- effects are due to space occupation
-can occlude horns
describe transmissible venereal tumors
- canidae: dogs, foxes, wolves
- macrophage origin, abnormal chromosome number
- transmitted by contact: genital area, face, oral cavity
- karyotype change (change morphology of chromosomes)
describe noninfectious causes of pregnancy failure
- plant toxicity:
-veratrum californicum: ingestion on day 14 - cyclopia - fetal malformation: amorphous globosus (bovine)
- hydroamnios and hydroallantois:
-excessive accumulation of fluid in the amniotic and allantoic sacs
-more common with ARTs such as IVF and somatic cell nuclear cloning
describe dystocia
- major cause of still birth!
- for some reason, fetus stays longer in uterus/vaginal canal
- once engaged in the canal, the uterine vessels are compressed, so it better get out in time to take its first breath or it dies of hypoxia
how do you diagnose stillbirth fetus in the postmortem exam? STAR
- small dam, big fetus: common due to IVF and cloned animals
- edema, congestion: of tongue, ventral cervical area, in front of shoulders
- eponychia: still has slipper on hooves
- atelectasis: lung sinks in water or formalin
describe infectious causes of pregnancy failure
- protozoal infections:
-N. caninum
-T. gondii - viral infections: BHV1, EHV1, EVA
- bacterial infections: brucella!!! and many more
describe infectious abortions STAR
- bacteria, fungus, protozoa are HUGE so they usually infect the PLACENTA and cause placental insufficiency
-fetus dies due to hypoxia and lack of nutrients - viruses: super super tiny so usually pass right through placenta and into the fetus and kill the fetus directly
-some bacteria can infect
how do infectious agents cause fetal death?
- bacteria, fungi, protozoa
-cows: hematogenous spread
-mares: floppy cervix so usually ascending infection
pathogenesis:
-hematogenous or ascending route
-placenta become infected
-microorganism proliferates in trophoblasts in the placenta
-decreased gas and nutrient exchange between mother and fetus
-fetus dies of hypoxia with no evident lesions
describe bacterial placentitis diagnosis STAR WILL BE ON EXAM!!!!!!!!
ABOMASAL/STOMACH contents MUST be collected when the placenta is way too dirty for a proper culture or isolation
most important tissues to collect from a cast of abortion:
-PLACENTA FIRST
-abomasal/stomach fluid if placenta nasty
-from fetus: liver, lung, kidney, brain: all viruses will be here! viral abortions usually have low to none gross and micro lesions
describe brucella abortus STAR
- reportable and zoonotic!!
- spreads via oral, inhalation, and mucosal contact/exposure to infected to placental fluids
- infects pregnant uterus, testes (in bulls), and mammae
- infects trophoblasts!! replicates in periplacentomal and interplacentomal trophoblasts
- necrotizing placentitis (intercotyledonary) with marked efems
-thickening and edema of the intercotyledonary chorioallantois
-fibronecrosis of the intercotyledonary chorion
describe bacterial placentitis due to brucella abortus STAR
- large numbers of bacteria are observed in trophoblasts and there is vasculitis in both maternal and fetal tissues
- fetuses develop pneumonia that ranges from minimal to severe
- granulomas that include multinucleate giant cells in lung, liver, spleen, and lymph nodes
describe campylobacter fetus fetus STAR
- necrotizing placentitis (cotyledonary) and viral fetal hepatic necrosis
- fetus dies of liver failure!!
describe toxoplasma/neospora placentitis
T. gondii: cats and sheep/goats
N. caninum: dogs and cattle
placenta: multifocal areas of necrosis
-WHITE dots in cotyledons = toxo has been here and exploded the cells
death due to placentitis
describe main organisms causing swine fetal death and infertility
- PRRS
- porcine parvovirus
- porcine cicrovirus
- pseudorabies
describe testicular hypoplasia STAR ON EXAM
- bilateral
-in bulls persistently infected with BVD - seminiferous tubules are small, woth marked thickening of basement membrane
describe cryptorchidism STAR ON EXAM
- failure or incomplete descent of testis and associated structures into the scrotum
- descent usually occur before birth in most species except
-dogs: by 3-6 months
-horses; 30 days prepartum and 1st ten days after birth; dx after 2 years of age only - congenital/genetic: testes can be anywhere from caudal to kidney to the external inguinal ring/subcutis
- if animal is lucky, increased body temp causes hypoplasia and also degen/atrophy and lack of spermatogenesis
-affects fertility: uni or nilat
-inheritable - if animal not lucky
-stays up in abdominal cavity, will often become neoplastic (dogs and horses)
describe sustentacular/sertoli cell tumors STAR ON EXAM!!!!!!!
- feminization syndrome due to estrogen secretion, causes prostatic squamous metaplasia
- atrophy: testes and penis
- attractive to other male dogs
- gynecomastia: development of mammary tissue in males
- anemia: bone marrow aplasia
