Large Animal Lab Exam Flashcards
BCS in Bulls
Beef
Scale 1-9
Ideal 6-7
Dairy
Scale 1-5
Using Oxytocin & PGF2 Alpha for Bulls During Electroejaculation
Oxytocin
Increases contractility of epididemus
Increased sperm output
Decrease time to penile protrusion
Decrease amount of stimulation needed
PGF2 Alpha
Increased sperm output in buffalo but not bull
Cranial (anterior) Presentation of Fetus
o Head & feet facing vaginal opening
o Fetlocks & carpal joints bending same direction
Caudal (Posterior) Presentation of Fetus
o Head facing away from vaginal opening
o Feet facing vaginal opening
o Fetlocks & carpal joints bend opposite directions
Transverse Ventral or Dorsal Position of Fetus
o Calf folded in half
o Feet and head face away from vaginal opening
Ventral
Head and chest more ventral than legs
Dorsal
Head and chest more dorsal than legs
Dorsosacral Vs Dorso-ilial Vs Dorsopubic
Dorsosacral
Normal
Dorso-ilial
To the left or right
Dorsopubic
Upside down
When is Vaginal Delivery Possible in Anterior or Posterior Dorsosacral Presentation in Cows
Anterior dorsosacral position
if one person can pull the fetlocks 10 to 15 cm beyond the vulva
Point of the shoulders at the level of the ilial shafts
Posterior dorsosacral position
If the hock can be exteriorized
When is Vaginal Delivery Impossible in Cows
o The head has not moved spontaneously into the pelvis
o Fetus is positioned in the birth canal and the forelimbs are crossed (fetus too wide at the shoulder)
o Hooves are rotated with volar surfaces facing medially (i.e. elbows are forced together)
o Fetus is lodged and does not move when abdominal press occurs
Repulsion; Technique, Requirements
o “Pushing” the fetus away from the pelvis to make room for manipulations
Requirements
Relaxed uterus w/ Clenbuterol or Epinephrine
Eliminate abdominal expulsive efforts w/ Caudal epidural
Lubrication (pump water soluble lubricant)
Can be done manually or use of the Kuhn’s crutch
Rotation
o Turning the fetus on its longitudinal axis
o Partial to take advantage of the largest diameter of the pelvis
o Complete to bring fetus from dorsoilial or dorsopubic to dorsosacral
o Can be done manually using the fetal limbs
o Use of a detorsion rod
Version
o Applied in transverse presentation
o Usually not possible in ventral transverses
Extraction of Calf Fetus w/ Chains
o Loop chains above fetlock
o Half hitch around pastern
o Maximum 2 / 3 persons or 600-800 lpi of force
o one foot at the time
o Pull in arc direction
o Traction on head to avoid neck flexion
o Calf pullers aren’t great
Calf Extraction Technique for Posterior Presentation
o Rotate the fetus 45 to 90 degrees
o Check if there is risk of hip lock by extending the hock outside the vulva
BCS of Dairy Cows
Tuber coxae -> hip joint -> tuber ischii
V shape <3
Curve >3.25
Hooks & pins from behind
Rounded = 3
Angular <3
Indirect Uterine Retraction in Cows
o Grasp cervix and pin to opposite side of palpating arm ->
o Reach for the broad ligament on side of palpating arm ->
o Hook the VENTRAL intercornual ligament ->
o Flip the uterus dorsally
Palpating Cow During Estrus & Immediately After Ovulation
Palpating During Estrus
o Ovary is round and smooth
o Dominant follicle present - Blister-like, fluid filled, continuous with ovarian stroma (12-25 mm)
o High estradiol
o Uterus is toned
o LSRF20UTone
Palpating Immediately After Ovulation
o dominant follicle is replaced by an ovulation depression (OVD)
o Uterus still has some tone or edematous
o Vaginal discharge may be bloody
o LS RFOVD U Tone/edema
Palpating a Cow at Days 0, 1, & 2-3 of her Cycle
Palpating Day 0 of Cow Cycle
o 15-25mm follicle
o Toned uterus
o Estrus
o High estrogen
Palpating Day 1 of Cow Cycle
o OVD
o Toned uterus
o Ovulation
o LH surge
Palpating Day 2-3 of Cow Cycle
o CH1 (Corpus Hemorrhagicum), soft, <1cm diemeter
o Edema
o Metaestrus
o Not responsive to PGF 2 alpha
Palpating a Cow at Days 3-5, 5-6, & 7-17 of her Cycle
Palpating Day 3-5 of Cow Cycle
o CH2, soft, 1-2cm diameter
o some edema or relaxed uterus
o Not responsive to PGF 2 alpha
Palpating Day 5-6 of Cow Cycle
o CH3, 2-3cm diameter
o Relaxed uterus
o Early luteal phase
o Progesterone >2
o Will respond to PGF2 alpha
Palpating Day 7-17 of Cow Cycle
o CL 3, > 2 cm diameter
o Relaxed uterus
o Mid cycle
o Progesterone plateau
o Will respond to PGF2 alpha
Palpating a Cow at Days 17-19 & 20-21 of her Cycle
Day 17-19 of Cow Cycle
o CL 2, 1-2cm diameter
o Uterus beginning to tone
o Proestrus
o PGF2 alpha release
Day 20-21 of Cow Cycle
o CL 1 or no CL, <1cm diameter
o Follicle present
o Toned uterus
o Estrus
o High estrogen
Indications of Pregnant Cow on Palpation
o Amniotic vesicle: palpable 28-60 days
o Fetal membrane slip: 30d to term (MOST IMPORTANT)
o Placentomes: 70d to term
o Fetus: 60d days to term
Pregnancy Diagnosis in Cow on Palpation at 35 Days, 42-45 days, 50 days, & 60 days
35 Days
o Membrane slip - thread
o Amniotic vesicle – 1 finger
42-45 Days
o Membrane slip – string
o Amniotic vesicle – 2 fingers
50 Days
o Membrane slip – both uterine horns
o Amniotic vesicle – 3 fingers
60 Days
o Membrane slip – both uterine horns
o Amniotic vesicle – palm
o Fetus the size of a mouse
o Can sex fetus w/ ultrasound
Pregnancy Diagnosis on Palpation at 75+ days
Placentomes (caruncle + cotyledon)
90 days = dime size
110 days = nickel
120 days = quarter
150 days = half dollar
Fetus
90 days = rat size
120 days = kitten
150 days = cat
180 days = medium dog
Fremitus
o turbulence of blood in the middle uterine artery located in the broad ligament of the pregnant horn.
o NOT a positive sign of pregnancy
When to Inseminate a Cow
o 12hrs after first sign of standing estrus
Proper Bull Semen Handling for Insemination
o LN Tank should not be in contact with floor
o Maintain straw in liquid nitrogen until use ->
o Thaw straw at 95°F (35°C) for 45 seconds ->
o Dry straw and load in a clean warm AI gun ->
o Use plastic protector of cannula to avoid contamination ->
o AI should be performed within 10 minutes of thawing
Cow Insemination Method
o ID cervix ->
o Hold cervix longitudinally & cranially to stretch vaginal tissue ->
o ID external cervical os ->
o Advance gun through cervical rings ->
o Deposit semen in uterine body
o May also be deposited in uterine horn if inseminator is very experienced
Normal Conformation of Equine Vulva & Perineum
o dorsal commissure should not incline more than 10 degrees from vertical
o 2/3 or more of the vulva should be below the horizontal plane of the ischial arch
o Minimal dorsal displacement when pushed
Non-Reproductive Organs Felt on Rectal Palpation of Mare
Left
L kidney
Edge of spleen
Pelvic flexure of large colon
Maybe small colon
Right
Cecum
Uterine Changes During Mare Cycle Felt on Transrectal Palpation
Anestrus
Flaccid uterus
Estrus /follicular Phase
Edematous & heavy uterus
Estrogen dominance
Diestrus/ Luteal Phase
Toned & tubular uterus
Progesterone dominance
Palpation of Mare Ovaries & follicle sizes
o Kidney shape w/ ovulation fossa
o 3x5cm
o Dominant follicle – 28mm
o Pre-ovulatory follicle – 40-60mm, soft, sensitive
o CL NOT palpable
Early – Severe Small Intestinal Distention Felt on Transrectal Palpation of Mare
o Will feel loops of intestine in early
o Will feel firm hotdog shapes if severe
o Ileal impaction
o Ileocecal intussusception
o Strangulating lipoma
o Epiploic foramen entrapment
o Small intestinal volvulus
Signs of Estrus on Ultrasound in Mare
o Uterine/endometrial edema
o Follicle >27mm
o Follicle grows by 5mm/day
Signs of Pre-ovulation on Ultrasound in Mare
o Uterine edema begins to decrease
o Follicular wall develops edema
o Pear shaped follicle
Pregnancy Diagnosis Timing W/ Transrectal Ultrasound or Palpation of a Mare
Ultrasound
Commonly 14 days (may be diagnosed as early as 10 days)
Palpation
Very skilled veterinarian: 18 days
Good skills: 20-22 days
Average skill: 25 – 30 days
Day 1: 35 days
What to Look For on Transrectal Ultrasound for Pregnancy Diagnosis on a Mare
o Over time allantois increase & yolk sac decrease
16-17 days
Vesicle fixation at base of horn
20-21 days
Loss of spherical shape & visible embryo
24-25d
Heartbeat
35d
Endometrial cups
Accessory corpora lutea
42d
Organogenesis
Placentation
Mare Vaginal Exam Tools
Vaginoscope
Plastic or cardboard
Single-use
Visualize the cervix only
Polanski Speculum
Stainless steel
Multiple use
Visualize the entire vaginal vault, cervix, and urethral opening
Best speculum for complete vaginal & Postpartum examination
Performing Uterine Culture or Cytology on a Mare
o Insert instrument halfway into cervix ->
o Remove safety & push 2nd guard in ->
o Push swab or brush gently until it contacts the endometrium ->
o Rotate in the same direction 10-15 revolutions ->
o Retrieve the system in reverse (inner guard, then outer guard, then come out)
Mare Endometrial Biopsy; Basics, Method
o gold standard for fertility prognosis
o can also be used for culture
o Sample size 20x4x3mm
o Sample from the base of the horn, dorsal aspect
How To
Closed biopsy instrument is carried sterilely into the vagina ->
Into uterine cavity through cervix ->
place the arm in the rectum and identify by palpation the jaws of the punch ->
gently depress the uterus by transrectal palpation so an endometrial fold is trapped in the biopsy jaw ->
remove piece of endometrial fold & place in 10% formalin
Kenney-Doig Classification System of Mare Endometrial Biopsies
I
>80% foaling rate
No changes to tissue
IIA
50-80% foaling rate
Slight-moderate cellular infiltrate
<2 fibrotic nests
Can revert to I w/ treatment
IIB
10-50% foaling rate
widespread moderately severe inflammation
2-4 fibrotic nests
Infertility for > 2 seasons
Can revert to IIA with treatment
III
<10% foaling rate
Widespread periglandular and perivascular fibrosis
> 5 nests
Hypoplastic endometrium
Neoplastic endometrium
poor prognosis
