Theriogenology Week 9 PDF

✨ Review this stuff: - the MOA b/w hCG and GnRH -hCG is LH-like - GnRH takes longer (goes to ant. pit) - mare already ovulated - AI - shorten luteal phase and use PGF2a - flushing donor/ recipient - 21 d cycle, 4-7 heat, 24-48 hrs in there (ov.) - donor - ov. Wed. (day 0) will be flushed during day...

✨ Review this stuff: - the MOA b/w hCG and GnRH -hCG is LH-like - GnRH takes longer (goes to ant. pit) - mare already ovulated - AI - shorten luteal phase and use PGF2a - flushing donor/ recipient - 21 d cycle, 4-7 heat, 24-48 hrs in there (ov.) - donor - ov. Wed. (day 0) will be flushed during day 8 that means you will be at post-ov day 8 - need to induce recipient mare around the same time that donor was ovulated (want her in diestrus) - infxs endometritis - tx: lavage, abx - embryo fixation - day 16 - sample type methods - swab, lavage, bx - Q fb question - lost pregnancy @55d, is there a problem w/ cycling her? yes - Q - supplementation until 120 d; (placenta/ CLs takes over w/ relaxin) - heartbeat 25d - Q doppler (KNOW PICTURES of doppler) - facebook q: day 8 embryo - anembryonic vesicle vibes / blighted embryo - fluid was there theriogenology week 9 Ashley Vasel non-infectious causes of abortion umbilical cord torsion uterine body pregnancy fescue toxicosis normal cord is ~55cm with 4-5 twists embryo fixed in uterine body fescue grass contaminated with fungus (acremonium) – move horse off fetus is highly mobile composed of: 2 arteries, 1 vein, urachus longer cords at risk for torsion fetus moves a lot, messing w/ circulation pathologic cords have > 7 twists CS: edema, hemorrhage, dilation of urachus placental insufficiency pasture! placenta is not big enough thickened placenta, no udder devel., check shape of placenta surgically agalactaie, low relaxin [] – has a conical shape prolonged gestation → less dilation IF dx early, terminate pregnancy for → low relaxin so no relaxation.... → her safety dystocia tx: supplement with dopamine receptor antagonist sulpiride or domperidone before birth Try to get milk by adding the dopamine receptor antagonist vet prep J VET PREP J VET PREP J - nocardia is worse than just placentitis bc the baby tries to conserve its E - note: tx baby needs estrogen - do thats why you add altre. placentitis ascending from vagina to cervix and attack placenta nocardioform placentitis hematogenous infection causing sporadic abortion fetal infection occurs (via umbilicus or amniotic fluid) #1. Streptococcus zooepidemicus, #2 E. coli / #1. Candida use normal Combined Thickness of Uterus and Placenta vs. placentitis uterus to evaluate placentitis focal placentitis, esp. uterine body and base of horns DIFFERENT bact causing HEMATOGENOUS SPPREAD characteristic exudate notice exudate accumulating b/w placenta and uterus & thickening norm. thickness correlates with stage of preg. → 9mo preg., 9mm thickness diagnostics look at fetal fluid! should be black but if abnormal you will see gray spots!! serum amyloid A – normal = 5, placentitis = 500-800!! estrogens – the fetus is supposed to make them! allantoic fluid amniotic fluid fetal heart rate IF decreased (< 60bpm for a prolonged time), trying to conserve resources clinical signs treatment early disease antimicrobials (TMS, ceftiofur) mare shows no signs, pregnancy is just lost late pregnancy (7-9mo) inflamed placenta → baby stressed, incr. fetal HR, hypoxia premature devel. of mammary glands or lactation, cr. vaginal secretion anti-inflam. (flunixin, pentoxifylline [makes RBCs more deformable to help with capillay circulation]) altrenogest – placentitis mares get 2x a dose that a healthy would get estrogen VET PREP J abortion & placentitis EHV-1 (equine herpes) late abortion mare is infected → rapid placental detachment & abortion → fetus is seen fresh within its membranes mycotic – Aspergillus fumigatus & Candida sporadic not always ascending, could be d/t feed contamination history of stress, mixing of groups, recent travel, etc. assoc. with chr. extensive placentitis at cervical star necropsy: pulmonary edema, hepatic necrosis white thick lesions – can look like ringworm isolate – intranuclear inclusion bodies on histo! mare reproductive loss syndrome (MRLS) prevent with vaccinations! – 5, 7, 9mo of gestation Spring 2001 in Kentucky 1/3 of mares aborted Leptospirosis d/t Eastern tent caterpillars abort late fall – November with no CS theory: mares in contact with wildlife are affected could use equine vx setae from caterpillar penetrate intestine → bacteremia OR setae entered circulation → penetrated the placenta early and late pregnancy losses U/S = debris in fetal fluid instead of anechoic / black non-repro lesion = uveitis, fibrin pericarditis, encephalitis VET PREP J vet prep J vet prep J VET PREP J vet prep! ZUKU J other conditions uterine torsion hydrops rare in mares bc broad ligament holds uterus v. stable rare in mares occurs mid to late pregnancy slowly develops a very large abdomen unrelated to parturition vs. cows and camelids it occurs for them during the stage of labor and is a cause of dystocia!!! 1st she will be uncomfy trying to breathe – abort! help with parturition, uterus is too stretched colic signs / abdominal pain if successful, mare and baby can survive diagnose via rectal palpation – easy to dx ruptured prepubic tendon correct by standing flank laparotomy and flip back into difficult to fix normal position acute condition could try... and correct by rolling salvaging the foal good prognosis once corrected prevent straining by passing tracheal tube do an abdominal body wrap VET PREP J vet prep J FOALING & DY S T O C I A foaling ex Q: mare in gest. day 360, breed with idk what semen; - what should you do? nothing. GESTATION CAN BE THAT LONG length of gestation pregnant mare care 335-342d – variable parasite control, routine dentrsiry, etc. premature < 320d may go over 365d without complication nutriton – do not over feed! obesity can lead to dystocia 5-10d longer early in season continue regular exercise J can prevent early season long pregnancy by using artificial lighting fetal wellness monitoring ergot alkaloids / fescue toxicity can prolong combined thickness of uterus and placenta vaccination fetal HR, vaginal discharge, udder development inactivated vx sfae just waiting for birth to happen MLV safe → EHV1, WNV, intranasal strangles / influenza normal birth do NOT use Venez. Eq. Encepahlitis (VEE) vx – abortion risk! booster for tetanus before birth booster rabies IF left to their own, foals will birth in the middle of the night bad if you are unaware and they have foaling problems (which are a common occurrence) mares can uniquely control when actual birth occurs vet prep J foaling (cont.) signs of impending parturition first stage of parturition – 1-24hrs move base of tail side to side and up and down closer to birth → tail base is easier to manipulate bc sacrosciatic ligament is softening cervix relaxes and uterine contractions begin vulva longer and softer mammary gland development teat fills in final days ~48hrs before birth teats leak a waxy viscous colostrum pre-monitory changes measure mammary gland secretion starts as serum-like → electrolyte changes to milk (secretions change) posture to urinate, pawing, sweating, restless lay down and get up frequently second stage of parturition - ~15min rupture of the CHORIOALLANTOIS → expulsion of allantoic fluid FIRST see white, translucent membrane amnion that surrounds fetus THEN fetal expulsion – fetal oversize almost never happens J third stage of parturition - ~1hr incr. Ca, decr. Na, incr. K – tastes sweet (less Na.. so less salty) passage of fetal membranes drop in pH – to 6.4 post-parturition can attach an alarm – magnets pull apart when vulva lips open → alarm – but alarms when mare is laying so cameras are good too mare will lick baby and encourage it to get up and nurse IF baby has not suckled by 2hrs → milk mare → stick tube in foal so it gets its colostrum vet prep normal parturition goals: 1hr = foal stands up 2hr = foal is nursing 3hrs = deliver the placenta & meconium evaluating the placenta - the surfaces had different colors weigh it, but don’t have to fun fact: should way 11% of the foal’s BW lay out placenta and see if it is intact, check for changes in color, look for signs of placentitis white and black arrows point at horns clear arrow is pointing at amnion bottom left redness is the rupture of the cervical star allantoic surface chorionic surface foaling (cont.) abnormal placenta hippomane tip of horn not intact, so a piece of placenta is stuck somewhere! present in the allantoic space! (normal ball of formed cells) unruptured cervical star (picture) ossified yolk sac bony structure, sometimes happens but not abnormal hyperplasia normal vairant abnormal amnion should be clear if big and thick check on baby, may need intervention not baby poop LOL birth unruptured chorion aka red bag placenta detached & cervical star is at the vulva lots of uterus detached from placenta indicates foal has been hypoxic – emergency!! cut the chorion and deliver the fetus ASAP colostrum – passive transfer of immunity (IgG) to bb!! measure with radial immunodiffusion – > 8,000 IgG is v good or brix refractometer – want > 20-30!!! vet prep J vet prep J vet prep J dystocia usually due to malposture maternal fetal disproportion is very rare caution: J-lube is toxic to the abdomen, caution if this patient will need sx!! C-section if baby is alive and high value equine anesthesia is a headache – their lungs are huge and they’re on their back fetotomy indications: dead fetus, plenty of space to work (dilated cervix) ideally be able to cut the foal into 3 not the cheaper option inducing abortion daily PGF2a injection dilate cervix with PGE2 then give a low dose of oxytocin inducing lactation mom is not making milk or we need a nurse mare 1. high dose of estradiol daily for 5-7d 2. also give an antidopaminergic – domperidone/sulpiride induces prolactin, so helps prod. milk can hand milk 4-5d after this introduce baby to mom 3-5d after milking give PGF2a IF mare has a CL so that way we can move forward with making milk post-partum mare monitor for.... retained fetal membranes placental passage want it out in an hour non-pregnant horn > pregnant horn bc it was not attached / relevant so deeper in there concern if it takes > 3hrs – laminitis !!! prevent laminitis!! – always our biggest concern! lochia foot pads / ice uterine involution caution for metritis uterine prolapse NSAIDs, antibiotics very rare d/t prolonged parturition or other disease when putting back, be sure its back in the normal position THEN give frequent small doses of oxytocin uterine atery rupture catastrophic!! usually older mares freq. small doses of oxytocin dutch technique: place catheter in veins of umbilical cords, inflate with air or water, will detach placenta from uterus J exercise, gentle manual extraction VET PREP J vet prep J foal heat breeding – aka first cycle of the mare after birth gestation and foaling causes very little change to the uterus can ovulate (7-10d post-parturition) and get pregnant very quickly again owners will rush to breed their horse but there is a much higher rate of loss! wait until the next cycle before breeding could give PGF2a to induce a shorter cycle and then breed neonatal isoerythrolysis aka jaundice foal syndrome mom’s antibodies attack the foal’s RBC you can screen mom to prevent this usually more common in multiparous dams (not a first time mama) Vet prep: for neonatal isoerythrolysis to occur, which of these pairs must mate? stallion POSITIVE for Qa or + Aa mare NEGATIVE for Qa or - Aa....so the foal gets the antigen from dad, meanwhile mom is negative when mom gets exposed to the foal’s RBCs antigens she will make antibodies bc like who tf r u lemme protect myself tf the baby is born, drinks moms colostrum full of immunoglobulins, then boom gives those antibodies to the thirsty lil baby, acute hemolysis occurs in the foal vet prep J vet prep J vet prep J vet prep J stallions using a male with an extraordinary athletic carrier or a big producer (good offspring) high fertility can impregnant as many females as possible in a short period differences among horse breeds thoroughbred → can only use live sperm types of stud fee commercialization a life foal guarantee single service (whether preg. or not) breeding dose / straws (frozen semen) not commercialized in thoroughbred tho breeding season not as imp. in stallions compared to mares, duh males are always going to produce sperm could travel stallion to diff. areas to breed with mares in season 2 breeding soundness exam when to perform investigating a problem fertility probs or semen collection epididymis tail of epididymis should be caudal - IF cranial = torsion!! scrotum and prepuce routine pre-season / freezing look for swelling, wounds, etc. pre-sale d/t trauma, hernia, cutaneous habronemiasis, etc. history penis ID’ing horse is imp.! esp. for future conflicts manual extraction not possible want them to have libido and mating ability use sedation and they will expose it – acepromazine or xylazine musculoskeletal – lameness exam caution, ace can cause penile priapism inherited defects → do not breed eval. gland and urethral process scrotum (testis & epididymis) internal genitalia presence, size, swelling, shape (oval & symmetric) accessory glands: seminal vesicles, ampulla, prostate, bulbourethral gland positioned horizontal with body of horse fibroelastic consistency eval. by rectal palpation, U/S, or endoscopy (an upside down image) total scrotal width and testicular volume w/ Pachymeter sedation! excitement can result in fluid turgidity or ejaculation mature width = 4.5-6cm | height = 5-8cm | length = 8.5-12cm 3 diameters to evaluate the volume measuring testes anechoic line = central vein (R) can use ultrasound to get accurate measurements start with pampiniform plexus (L) could do after semen collection bc stallion is more relaxed disorders: plugged ampullae, seminal vesiculitis, tumors, urethral rent 3 accessory glands on U/S 4 semen collection requires lots of training chemical ejaculation – last option pre-collection low success rates L this xylazine is going to give me the best ejaculation of my life usually need an ovariectomized mare or mare in estrus d/t an adrenergic response to excite the stallion imipramine IV wash / lavage the penis with water !! reduces need to respond to ejaculation esp. the urethral fossa!! then dry it! if you do not clean semen will be dirty, full of cells, etc. forms of semen collection artificial vagina can give give oral form 1hr prior xylazine (most commonly) or detomidine oxytocin stallion’s behavior during collection req.: 42-48oC water temp., pressure, lube tail movements with a dummy he can mount (most common) contraction of perianal muscles or just on ground with artificial vagina manual manipulation – uncommon condom tap dance urethral pulses 5 semen analysis use a nylon filter to get gel out of the semen! morphology be sure you’re maintaining 35oC – normal sperm environ. > 60% – head + acrosome, midpiece, tail min. 1 billion (× 109) progressively motile, morphologically normal sperm in the second of two ejaculates collected 1hr apart after a week of sexual rest obj. analysis using computer assisted technology (CASA) goals DIC (differential interference contrast) – gold standard, $$$ gel free vol. (filtered semen) = 50ml stains: Karras, Diff-Quick, eosin-nigrosin color and consistency = white to gray (looks like milk) viability – checking plasma membrane integrity odor = suis generis be sure you can have an acrosomal rxn for fertilization sperm concentration ~120 million per mL evaluation 5-15 billion sperm per total ejaculate Newbauer champer (#1) = manual count Densimeter = [] via density of semen hiposmotic test using water, looking for a non-bent tail eosin-negrosin stain white = viable pink = bad fluorescent microscopy green = viable Nucleo counter – most precise = [] via DNA seminal plasma alkaline phosphatase motility protein is prod. in high levels (25,000) in the epididymis > 60% IF low < 1500 consider pathology subjectively via microscope or use objectively with CASA IF there is a blockage, sample will be < 100 u/L pH other tests 6.8-7.2 DNA stability, culture, cytology, hormone assays (ex. testosterone) 6 compensable vs. non-compensable defects compensable defect uncompensable defects will not be able to fertilize and compete with normal sperm double your sperm dose & you will compensate this defect can reach the oocyte and compete but it will never develop doubling the sperm dose will do nothing 7 factors that can affect semen freq. of semen collection first ejaculate will have a high number of sperm but a reduced quality second ejaculate will have reduced sperm number and increased sperm quality min. 1 billion (× 109) progressively motile, morphologically normal sperm in the second of two ejaculates collected 1hr apart after a week of sexual rest season, pathology, age and breed, therapies (hormones) 8 processing semen for AI fresh semen cooled semen frozen semen at least 500 million progressively motile sperm to impregnant mare use 1 billion progressively motile sperm (double dose) use 800 million to 1 billion sperm usually 8 0.5ml straws 9