Repro Path

Question 1

compare chromosomal versus gonadal sex determination STAR

Answer 1

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

Question 2

describe phenotypical sex determination STAR

Answer 2

hormonal secretion causes development of secondary sexual characteristics

-internal and external genitalia

Question 3

what can go wrong with sex determination?

Answer 3

1. chromosomal abnormalities
   -abnormal number and/or mixture of sex chromosomes
2. gonadal abnormalities
   -failure of effective signal to primitive and undifferentiated gonads
3. phenotypic abnormalities:
   -message did not get through to ensure development of mesonephric vs paramesonephric duct

Question 4

describe Turner syndrome

Answer 4

1. a chromosome is missing!
   -need 2 X’s to make all mediators in females, so can’t do that
2. common in mares
   -ovaries are hypoplastic, tract is rudimentary

Question 5

describe mosaic’s versus chimeras STAR

Answer 5

1. mosaicism: occurs when there are 2 or more genetically different cell lines present originating from a single zygote
2. chimerism: occurs when there are 2 or more genetically different cells lines present originating from 2 or more zygotes (freemartin)

Question 6

describe klinefelter’s syndrome STAR

Answer 6

1. polysomy: more than one X chromosome isn present
   -XXY karyotype or more complex
2. occurs in stallions, bulls, boars, dogs
3. cats: males with tricolor, tortoiseshell, or calico coat types
4. also leads to testicular hypoplasia
5. MALE CALICO CATS ARE USUALLY MOSAICS AND INFERTILE

Question 7

describe intersex

Answer 7

1. associated with gonadal dysgenesis and a female phenotype
2. true hermaphrodite has to have both gonads (ovotestis) = RARE
3. 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

Question 8

describe developmental ovary conditions

Answer 8

1. agenesis: RARE
   -can be uni or bilateral
2. hypoplasia:
   -XXX and X_ in mares and XXX in cows
   -swedish highland cattle: autosomal recessive trait
3. 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

Question 9

describe developmental uterus, vagina, vulva conditions

Answer 9

1. segmental aplasia: can happen at any portion of repro tubular organs
2. 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

Question 10

where can cysts occur?

Answer 10

not just ovaries!

intraovarian, periovarian, uterine, vaginal, vestibular

Question 11

describe peri (para) ovarian cysts STAR

Answer 11

EQUINE!!

1. 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

Question 12

describe ovarian tumors

Answer 12

1. epithelium: adenoma/adenocarcinoma
   -most common in dogs
2. carcinomatosis

Question 13

describe ovarian sex cord tumors

Answer 13

1. 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

2. frequently produce hormones
3. generally unilateral and benign

Question 14

describe teratomas

Answer 14

1. germ cell derived neoplasm
2. often have bits of bone or liver or other tissue all mixed in together

Question 15

describe uterine adenocarcinomas STAR

Answer 15

1. particularly common in older rabbits
2. malignant and metastasize often!!
   -come from epithelial cells

Question 16

describe leiomyomas STAR

Answer 16

1. benign form of smooth muscle neoplasia
2. usually solitary, but can be multiples
3. effects are due to space occupation
   -can occlude horns

Question 17

describe transmissible venereal tumors

Answer 17

1. canidae: dogs, foxes, wolves
2. macrophage origin, abnormal chromosome number
3. transmitted by contact: genital area, face, oral cavity
4. karyotype change (change morphology of chromosomes)

Question 18

describe noninfectious causes of pregnancy failure

Answer 18

1. plant toxicity:
   -veratrum californicum: ingestion on day 14 - cyclopia
2. fetal malformation: amorphous globosus (bovine)
3. 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

Question 19

describe dystocia

Answer 19

1. major cause of still birth!
2. for some reason, fetus stays longer in uterus/vaginal canal
3. 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

Question 20

how do you diagnose stillbirth fetus in the postmortem exam? STAR

Answer 20

1. small dam, big fetus: common due to IVF and cloned animals
2. edema, congestion: of tongue, ventral cervical area, in front of shoulders
3. eponychia: still has slipper on hooves
4. atelectasis: lung sinks in water or formalin

Question 21

describe infectious causes of pregnancy failure

Answer 21

1. protozoal infections:
   -N. caninum
   -T. gondii
2. viral infections: BHV1, EHV1, EVA
3. bacterial infections: brucella!!! and many more

Question 22

describe infectious abortions STAR

Answer 22

1. bacteria, fungus, protozoa are HUGE so they usually infect the PLACENTA and cause placental insufficiency
   -fetus dies due to hypoxia and lack of nutrients
2. viruses: super super tiny so usually pass right through placenta and into the fetus and kill the fetus directly

-some bacteria can infect

Question 23

how do infectious agents cause fetal death?

Answer 23

1. 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

Question 24

describe bacterial placentitis diagnosis STAR WILL BE ON EXAM!!!!!!!!

Answer 24

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

Question 25

describe brucella abortus STAR

Answer 25

1. reportable and zoonotic!! 2. spreads via oral, inhalation, and mucosal contact/exposure to infected to placental fluids 3. infects pregnant uterus, testes (in bulls), and mammae 4. infects trophoblasts!! replicates in periplacentomal and interplacentomal trophoblasts 5. necrotizing placentitis (intercotyledonary) with marked efems -thickening and edema of the intercotyledonary chorioallantois -fibronecrosis of the intercotyledonary chorion

Question 26

describe bacterial placentitis due to brucella abortus STAR

Answer 26

1. large numbers of bacteria are observed in trophoblasts and there is vasculitis in both maternal and fetal tissues 2. fetuses develop pneumonia that ranges from minimal to severe 3. granulomas that include multinucleate giant cells in lung, liver, spleen, and lymph nodes

Question 27

describe campylobacter fetus fetus STAR

Answer 27

1. necrotizing placentitis (cotyledonary) and viral fetal hepatic necrosis 2. fetus dies of liver failure!!

Question 28

describe toxoplasma/neospora placentitis

Answer 28

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

Question 29

describe main organisms causing swine fetal death and infertility

Answer 29

1. PRRS 2. porcine parvovirus 3. porcine cicrovirus 4. pseudorabies

Question 30

describe testicular hypoplasia STAR ON EXAM

Answer 30

1. bilateral -in bulls persistently infected with BVD 2. seminiferous tubules are small, woth marked thickening of basement membrane

Question 31

describe cryptorchidism STAR ON EXAM

Answer 31

1. failure or incomplete descent of testis and associated structures into the scrotum 2. 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 3. congenital/genetic: testes can be anywhere from caudal to kidney to the external inguinal ring/subcutis 4. if animal is lucky, increased body temp causes hypoplasia and also degen/atrophy and lack of spermatogenesis -affects fertility: uni or nilat -inheritable 5. if animal not lucky -stays up in abdominal cavity, will often become neoplastic (dogs and horses)

Question 32

describe sustentacular/sertoli cell tumors STAR ON EXAM!!!!!!!

Answer 32

1. feminization syndrome due to estrogen secretion, causes prostatic squamous metaplasia 2. atrophy: testes and penis 3. attractive to other male dogs 4. gynecomastia: development of mammary tissue in males 5. anemia: bone marrow aplasia