RPM: practice questions (week 1)

breeding goals/pre-breeding mgmt, AI, pregnancy dx, dystocia LA + SA, C-section, gestational/post-partum problems

Transrectal palpation in a cow showing signs of heat reveals a soft, round, fluid-filled structure (about 16 to 17 mm in diameter) in one of the two ovaries. What is the most appropriate description of this structure?

Graafian follicle

What are the firm structures, usually with a crown projecting beyond the surface of the ovary in a cow?

Corpus luteum

-or Corpus albicans

What structure within the ovary of a cow is abnormally large in size, usually greater than 25 mm in diameter?

Follicular cyst

On any given day, approximately how many cows in a group of 100 normal cycling non-pregnant cows are in estrus?

5 cows

-bovine estrous cycle is ~21 days (estrus is ~1 day so: 1/21×100=5)

On any given day, approximately how many cows in a group of 100 normal cycling non-pregnant cows are in proestrus?

15 cows

-bovine estrous cycle is ~21 days (proestrus is ~3 days so: 3/21×100=15)

On any given day, approximately how many cows in a group of 100 normal cycling non-pregnant cows are in metestrus?

20 cows

-bovine estrous cycle is ~21 days (metestrus is ~4 days so: 4/21×100=20)

On any given day, approximately how many cows in a group of 100 normal cycling non-pregnant cows are in diestrus?

60 cows

-bovine estrous cycle is ~21 days (diestrus is ~12 days so: 12/21×100=60)

If you visualize bloody discharge coming from the vulva of a cow, what condition is this likely indicative of?

Metestral bleeding (means cow has ovulated, but may or may not be pregnant)

What are the differences in breeding management between dairy vs. beef cattle?

Dairy: Heat detection followed by AI

Beef: Natural breeding systems → bulls run with cows during breeding season for 2-3mos

What is the most reliable primary sign of estrus in bovine?

Standing to be mounted

What are the common secondary signs of estrus in bovine, which may occur before, during, OR after estrus?

Attempting to mount other cows, clear mucous discharge from vulva, vulvar swelling/hyperemia, bellowing, restlessness, resting chin on other cows

Which heat detection aid will dye the test red in seconds if the cow is in heat/estrus?

Kamar Heatmount detector

What method of estrus detection is based on a secondary sign of estrus rather than standing to be mounted?

Pedometer → detects motion

What clinical signs will you find upon transrectal palpation + laboratory findings of a cow in estrus?

-Edematous + turgid uterus due to high estrogen

-Uterine horns tightly coiled

-Large follicle(s) present on ovary

-CL absent

-Low progesterone

What clinical signs will you find upon transrectal palpation + laboratory findings of a cow in diestrus?

-Relaxed uterus due to low progesterone

-Uterine horns relatively less coiled

-CL present on ovary

-Large follicle(s) may or may not be present

-High progesterone

What signs might you find upon ultrasound of a cow in estrus?

-Uterus may contain intraluminal fluid

-Follicles present on ovaries

What signs might you find upon ultrasound of a cow in diestrus?

-CL appears as soft tissue opacity on ovary + may have central fluid-filled cavity

-Follicles present on ovaries

Which estrus synchronization program in cattle works only in cycling animals with a responsive CL?

PGF2a-based programs → 2 injections 11-14 days apart for best results

-PGF2a regresses CL to start cycle over

What is the most likely outcome if you give an anovular cow an injection of PGF2a?

She will not respond to the injection as there is no CL to respond

Which estrus synchronization program mimics the luteal phase by inhibiting LH secretion + ovulation?

Progestagen-based programs

-works in both cycling + non-cycling animals

What is the ONLY FDA-approved progestagen used for estrus suppression in heifers?

Melengestrol acetate (MGA)

What is the most common GnRH-based estrus synchronization program used in dairy cows?

OvSynch protocol

-synchronizes estrus AND ovulation, but takes the most injections (3) + handlings (4)

What is the cycle for the OvSynch protocol used in dairy cattle for estrus synchronization?

Day 0: 1st GnRH injection → releases LH + FSH

Day 7: PGF2a injection → CL regresses

Day 9: 2nd GnRH injection → induces ovulation as follicle is now present

Day 10: Fixed-Time AI

What is the preferred GnRH-based estrus synchronization program used in beef cattle?

SelectSynch

-less injections (2) + handlings (2) = happier cows

-GnRH + PGF2a given 7 days apart

What is the most powerful stimulus for hastening onset of breeding season in small ruminants (within 3-4 days)?

Ram/Buck Effect

For the ram effect to work, what is the most important requirement?

The ewes must be separated from rams for at least a month prior to introduction of the ram

Estrus can be harder to detect in small ruminants. What are some of the only signs to look out for?

Slightly swollen/congested vulva + restlessness

What is the pheromone produced from testosterone in the submaxillary salivary gland that aids in the “boar effect” to help stimulate the onset of puberty or facilitate the detection of estrus in gilts + sows?

5-a-androstenone

In which species does PGF2a not work to synchronize estrus as their CL are not responsive to it?

Pigs

What are the components of a normal vulva in a mare?

-Upright vulva

-Good apposition of vulvar lips (vulvar seal)

-Have more than 2/3 to ¾ of the vulvar length below the base of pelvis

What can gaping of the vulvar lips or horizontal tipping of the vulva, which is often seen with low BCS/older mares/folding injuries, predispose mares to?

Pneumo-vagina or fecal contamination leading to infertility

After evaluation of the perineal conformation, what is the most logical next step in the BSE for a mare?

Transrectal palpation + ultrasound

In the mare, what are we feeling for as a landmark rather than the cervix during transrectal palpation?

Uterus (uterine bifurcation)

What will the texture + tone of the cervix be like during transrectal palpation of a mare in estrus?

Soft + low tone, difficult to palpate → low progesterone, high estrogen

What will the texture + tone of the cervix be like during transrectal palpation of a mare in diestrus?

Firm + high tone, tightly closed → high progesterone

How does palpation of the uterus during estrus differ in mares than in other species?

Decreased tone rather than increased tone

Where can you palpate the ovaries in the mare?

Just cranial to the iliach arches (10 + 2 o’clock)

What can grade 3 edema or edema during diestrus in the mare be a sign of?

Endometritis

If you visualize intraluminal fluid on ultrasound of the mare, what can this potentially be indicative of?

Pregnancy, Endometritis, or Pyometra

Transrectal examination of a mare indicates that the uterus is turgid with a Grade 2 edema & no intraluminal free fluid. The right ovary has a 40mm follicle & the left ovary has multiple small follicles. What is the best interpretation of these findings?

The mare is in estrus

How does the cervix appear in the mare during estrus upon visual examination?

On the floor of the vagina, pink, + moist

How does the cervix appear in the mare during diestrus upon visual examination?

Relatively dorsal/cranial in the vagina, pale + dry

When is the best time to do a manual/digital examination of the cervix in the mare?

During diestrus → cervix needs to be tightly closed

If evidence of inflammation from an endometrial cytology swab is found in a mare, but no bacteria is observed upon culture & sensitivity ruling out infection, what are the possibilities for these results?

Urine or air in vagina causing irritation

Greater than what number of neutrophils per hpf (view at least 10hpf on 40x) may indicate endometritis in the mare?

>1 neutrophil/hpf

What might a positive cytology (>1 neutrophil/hpf) with a negative culture (no bacterial growth) in a mare most likely indicate?

Non-infectious endometritis

-never just assume this → send multiple samples + test for fungus 1st

What might a negative cytology (<1 neutrophil/hpf) with a positive culture (bacterial growth) in a mare most likely indicate?

Contamination of the swab

Where do you obtain the sample from for an endometrial biopsy in a barren mare?

Base of uterine horn

Under what circumstances might you perform a hysteroscopy in a mare?

Suspect intraluminal foreign bodies (swab tips, glass marble) or Ablation of endometrial cysts

What is the normal orientation of testes within the scrotum of a bull?

Vertical

What is the average duration of spermatogenesis in the bull (sperm life cycle)?

60 days (2 months)

When should you perform a pre-breeding BSE in the bull?

60 days (2 months) prior to breeding

What would be the best sample to collect if we need to test a bull for Trich or Vibrio?

Preputial scraping → specimen live in preputial folds

Bulls with _____ scrotal circumference (SC) produce daughters (heifer calves) that attain puberty ______.

Higher, Earlier

What should normal testes feel like?

Firm + elastic

What is the main clinical sign noted in younger bulls affected by seminal vesiculitis?

Vocalization due to pain

What is the normal color/consistency, motility, & morphology of the semen of a bull, meaning the bull is a satisfactory potential breeder?

Color/consistency: Milky or creamy

Motility: >30%

Morphology: >70%

A 2yo Angus bull is presented for BSE. The bull is physically normal & his scrotal circumference is 36cm. His semen is milky with 50% progressive motility + 80% morphologically normal spermatozoa. What is the most correct evaluation of this bull?

Satisfactory potential breeder

When might you defer your decision to a later date (2 months later at least) during a BSE of a bull that does not meet the minimum requirements?

Young bulls with poor semen quality or mature bulls with a recent disturbance in spermatogenesis (ex: pyrexia)

A 12mo old Angus bull is presented for BSE. The bull is physically normal & his scrotal circumference is 32cm. His semen is watery with poor mass motility, <10% progressive motility, + 30% morphologically normal spermatozoa. What is the most correct recommendation?

Decision deferred; re-examine after 3 months

-young bull

What disease should you be thinking about during canine pre-breeding tests?

Brucella canis

In dogs, what hormone do people prefer to test for as the tests are cheaper?

Progesterone → test EOD

-ovulation occurs 2 days post-LH surge which happens at the same time as progesterone rises

When will you see cornified superficial cells on a vaginal cytology of a female dog?

Under the influence of estrogen

A 3yo Golden Retriever female dog is presented for breeding with chilled semen. The owner reports that the female dog came into heat yesterday. The vaginoscopy + vaginal cytology results are as shown in the pictures. What stage of the estrous cycle is she most likely in?

Proestrus

-pink + swollen, mix of cells

After sequentially monitoring a female dog that was initially in proestrus every other day for two weeks, the vaginoscopy + vaginal cytology results are as shown in the pictures. What stage of the estrous cycle is she most likely in?

Late estrus

-pale + wrinkled, superficial cells

During AI in a sow, the vet advances the insemination catheter through the vagina. Where should the semen be deposited using the conventional insemination technique? 

Cervix

What is the common breeding practice for canines without involvement of a veterinarian?

Breed 2-2 times at 48 hour intervals (ex: Day on 11 + 13)

Why is it best to transport the female dog to the male for conception after confirmation of ovulation has occurred rather than before ovulation?

Transport causes stress, which ↑ cortisol, which ↓ LH, which means no ovulation can occur

How can you manually collect semen from a male dog for vaginal insemination?

Apply pressure behind the bulbus glandis

-use latex-free gloves as latex can kill sperm

What is the best sperm fraction sample to use to assess the prostate in a male dog as this fraction comes only from the prostate?

Post-sperm fraction

What type of semen is more likely to result in higher pregnancy rates & bigger litter sizes when vaginal insemination is used in female dogs?

Fresh semen

A 3yo GSD female dog, who is to be bred with one dose of very expensive imported frozen semen, is examined. After sequential monitoring for ovulation, the vet has determined that she had her LH surge today. What would be the best day to breed the female dog?

After 5 days

-ovulation occurs 2 days post-LH surge, then the breeding window (highest fertility) will be 4-6 days post-LH surge

-if fresh semen, likely would breed after 4 days, but with frozen semen you would breed after 5-6 days

A horse owner asks for your help with hastening the onset of breeding season in a group of mares next year. What recommendation would be helpful in achieving that goal?

Put the mares under artificial light

A breeder wants to hasten the onset of breeding season next year in a group of mares using an artificial lighting program. How early should the program be started to get the earliest response?

November 15th

-fixed photoperiod typically begins 15 Nov-1st Dec, followed by lag period of 60-75 days so mare is ovulating by Feb

Which hormonal method for advancing breeding season in mares will suppress estrus but still allows follicles to grow, so that when we stop the treatment, the mare will be able to come into estrus?

Progesterone → inhibits LH

Which hormonal methods for advancing breeding season in mares are used to induce ovulation or hasten follicular growth + ovulation as long as the follicle is >35mm?

hCG (induce ovulation), GnRH (hasten follicular growth + ovulation)

What are the pre-requisites for using hCG to induce ovulation within 36-48 hours in the mare?

Follicle must be >35mm + Mare should be in estrus

When using GnRH to induce ovulation in the mare, what must you do after the mare has successfully ovulated?

REMOVE IMPLANT → can develop downregulation of GnRH

You used 1500 IU hCG for ovulation induction in a 15yo Standardbred mare & it did not work. What would you do differently in the next cycle?

Use Deslorelin instead of hCG

What method of breeding is allowed to produce a Thoroughbred foal that can be registered?

Natural mating/Live cover

-must also obtain uterine culture prior to breeding

A 5yo Thoroughbred mare is covered today by a resident stallion on the farm after showing receptive behavior on teasing. The stallion is available for multiple matings. What is the most appropriate next step?

Tease the mare day after tomorrow & breed her again if she is still receptive

For fresh semen AI in a horse, where is the semen usually deposited?

Uterine body

How long is fresh vs. chilled vs. frozen semen fertile for after insemination of a mare?

Fresh: 48 hours

Chilled: 24 hours

Frozen: 12 hours

An 8yo Standardbred mare is presented for breeding with chilled semen that is expected to take 24 hours for arrival after it is ordered. The mare has a grade 1 uterine edema & the largest follicle is about 25mm in diameter. What is the correct plan?

Re-examine her tomorrow → follicle is not yet >35mm for hCG to work

A 14yo Warmblood mare is presented for frozen semen breeding. On transrectal ultrasound, you observe a 40mm follicle in the right ovary, multiple small follicles in the left ovary & a grade 2 uterine edema. Which of the following is the best plan?

Give her GnRH, U/S every 6 hours until ovulation, & inseminate immediately after ovulation (12 hour window with frozen semen)

What is the normal post-breeding management for mares?

Uterine lavage with saline or LRS 6-12 hours after breeding

-Oxytocin every 4-6 hours if required

-Caslick’s surgery if required

When is the earliest you can diagnose pregnancy in dairy vs. beef cows via transrectal palpation?

Dairy: 35-42 days

Beef: 6-8 weeks after end of breeding season

What are the four definitive signs of pregnancy in the cow?

1. Amniotic vesicle

2. Fetal membrane/chorioallantoic membrane slip

3. Fetus

4. Placentomes (maternal caruncle + fetal cotyledon)

When should the amniotic vesicle be transrectally palpated in pregnant cows?

Day 42-65

-can be palpated at day 30 but should not do this as it can cause atresia coli

When should the fetal/chorioallantoic membrane slip be transrectally palpable in pregnant cows?

Day 30-end of gestation

When can the fetus be transrectally palpated vs. balloted in the pregnant cow?

Palpated: Day 65-4.5 months, & then after 6 months

Balloted: 4.5-6 months

When can placentomes be transrectally palpated in the pregnant cow?

Day 75-end of gestation

What are the suggestive signs of pregnancy rather than the definitive signs of pregnancy in a cow?

-Asymmetry of the uterine horns

-Resilience + fluctuance of the uterine wall

-Fixation of the cervix

-Hypertrophy + increased blood flow in the middle uterine artery (fremitus)

-Persistent CL

You are checking a herd of beef cows for pregnancy & find a cow in which the cervix appears to be fixed against the pelvic brim. Ballottement indicates a fluid-filled uterus but the fetus is not palpable. Palpation of the uterine wall indicates presence of multiple disc-shaped thickenings (placentomes). What is the correct diagnosis?

Pregnant

-fetus not palpable likely bc it is between 4.5-6 months pregnant

During a preg check visit to a dairy farm, you examine a cow in which the cervix is freely movable & one of the uterine horns feels bigger than the other. One of the ovaries has a CL on it. What is the most appropriate diagnosis?

Inconclusive; re-examine after a few days-a week

When is the earliest we can detect pregnancy in a cow via transrectal ultrasonography?

Day 30

-heartbeat visible day 25 though (fetal viability)

When can we determine the fetal calf gender via transrectal ultrasound?

Day 55-60 → genital tubercle close to umbilicus = male, close to tail = female

What hormonal method performed on day 21 post-insemination is 100% accurate (highly specific) for confirming a cow is NOT pregnant?

Progesterone (milk/serum)

When is the first pregnancy check typically performed via ultrasound in the mare?

Day 14 (2 weeks)

-embryo fixed on day 16

What are some of the main ways we can differentiate an endometrial cyst from an embryo upon ultrasound of the mare?

-Cysts will not move locations, but embryos will upon re-examination later that day

-Embryos will grow at a much faster rate (re-examine a few days later to monitor growth)

-Cysts will not have a heartbeat at 21 days

-Cysts may be much less perfectly spherical