109. Ovary and Uterus Flashcards
anatomy of the ovary
capsule –tunica albuginea (covered by peritoneum)ovarian bursa–double fold of peritoneum, blocked during ovulation by fimbriae of the infundibulumcortex—contains folliclesmesovarium from which arises the suspensory ligament and continuous with proper ligament and round ligament (passes thru inguinal canal)mesometrium/broad ligament
vascular supply to the ovary
–ovarian arteries from aorta–ovarian vein (R—VC, L–left renal vein)
what marks the junction of the peritoneum (mesosalpinx) with the mucus membrane lining of the uterine tube
fimbriae of the infundibulum near the opening of the ovarian bursaopening of the uterine tube into the uterine horn is called uterine osmium (tubulouterine junction–sphincter for passage of sperm and blastocysts)
layers or tunics of the uterus
–serosa–muscularis (myometrium)–smooth muscle inner thick circular, outter thing longitudinal –mucosa (endometrium)***thickest consists of epithelial cells that are occasionally ciliated and simple branched tubular glands
difference in dog vs cat cervix
dogs—diagonal across uterovaginal jxn (internal faces dorsal)cats—lies horizontal
vascular supply to the uterus
uterine arteries (branch of vaginal artery) anastomose with ovarian arteries
typical cycle stages and hormone release
–anestrus (low P, LH but E slowly climbs up)–proestrus (peak E, slow climb P during late proestrus, LH surge right before estrus/ovulation)–estrus (LH and E come back down, steady increase P) **cornified epithelial cells–metestrus/diestrus (steady decrease in P if no pregnancy or stays elevated if pregnant) 21-28 days of the ovarian cyclecats have a fifth stage of NONestrus during non cycling periods
difference in ovulation dogs vs cats
cats—induced (not dependent on E) ovulators (the formation of CL requires induced ovulation and the CL stays functional for 37 days)dogs—spontaneous ovulates (dependent on E) and then P maintains CL for 60-100 d in non pregnant bitches before it regresses
gestational length in bitches
57-72 days from first mating64 days from ovulation64-66 days from LH surge*accurate65 days +/- 3 days from P levels >1.5 ng/ml
detecting a fetal skeleton on radiographs
DAY 42 (or ~ 20 days before birth)
minimum data base abnormalities of a pregnant bitch
–normochromic anemia—hemodilution by increased plasma volume–mild leukocytosis, hypercholesterolemia, hyperproteinemia–HYPERGLYCEMIA from insulin resistance
signs of impending parturition
- < 2-3 ng/ml P 18-30 hr before giving birth2. temp drops <99-100 F 10-14 hr before giving birth (unreliable in cats)3. transcutaneous whelping monitors
three stages of parturition
I. nonvisable uterine contractions, nesting behavior–24 hrII and III. alternate as each fetus (II) and placenta (III) are passed; active uterine contractions presentlasts up to 36 hrsafter whelping, uterus involutes, lochia (odorless green brown hemorrhagic discharge) 4-6 weeks or longer
signs of distress during parturition
though normal pregnancy can take up to 36 hrs….dystocia should be considered if……1. lack of progression from stage I to II within 12-24 hrs2. active abdominal straining > 30 min b4 a puppy is seen3. time lag btwn puppies should not > 4 hrs4. failure to deliver pups within 36 hr5. lochia without delivery6. obstructed birth canal/fetal malposition on digital examination7. lack of Ferguson’s reflex (massage cervix and release endogenous oxytocin)8. signs of toxemia/systemic illness
time btwn first and last kittens was less the 6 hours in how many parturitions
86%(quicker than in dogs)
benefits of sterilization
- counteracts overpopulation2. decreases the likelihood of an animal being relinquished 3. may correct sexually dimorphic aggression (aggression btwn male and females in a house; NOT resolve nonsexual dimorphic behaviors)4. reduces the risk of mammary neoplasia 5. reduces the risk of pyometra and other uterine/ovarian diseases
incidence of pyometra in dogs
25% of intact bitches require treatment for pyometra by 10 yrs of agehormonal changes (diestrus) lead to cystic endometrial hyperplasia and secondary infxn (usually under P which stimulates gland secretion, suppresses uterine contraction and decreases ability of mononuclear cells to proliferate which dampens the immune response)ECOLItx with surgery OHE led to excellent px and survival in > 90%; peritonitis present 70% (with drains)
tumor types and diseases that have been overrepresented in gonadectomized animals
–TCC–OSA–HSA–Diabetes mellitus (cats)–Hypothyroidism (female dogs)–OBESTITY/decr metabolic rate (most common reported factor)–USMI (female—20% spayed dogs; multifactorial dz)–UTI (female dogs)–CCLR?
risks of timing of OHE to early
traditionally 6-9 mo (others 4 mo/after immunizations)shelters 6-16 weeks: riskS1. severe hypothermia— incr SA:V and less fat/vasoconstrictive reflexes, shaving/solutions2. hypoglycemia–inadequate liver stores and fx; avoid prolong fasting, give dextrose fluids3. immature liver/kidney fx–lack p450 enzymes in liver, leading to higher unbound drugs in circulation, risk side effects–need lower doses; inadequate kidney fx and low USG; inadequate RAAS system–prone to NSAID side effects4. incr demand on heart–avoid antichoinergicsIF appropriate surgery and anesthesia, prepubertal OHE does NOT carry incr risk
T/Fanticholinergics are recommended in pediatrics
FALSEdo NOT use anticholinergics in pediatric animals bcthey lack vagal tone and brady cardia may actually be more indicative of hypoxia (supplement oxygen)neonates (< 3weeks) may benefit from anticholinergics bc CO is more related to HR