Reproduction T1 Flashcards
Lectures covered in T1 for Final Exam
How long does it take for Spermatogenesis?
What is important to not about immature Spermatoza?
40-50 days. These sperm are immature and are unable to fertalise as they are immobile. They must tranverse the Epididymas to mature taking 10-14days.
Ejaculation can happen at sperm age of 60-65days
How many waves of follicle growth does
Horses
Cows
have?
- Horses 1-2 per cycle
- Cows 2-3 per cycle
In the Bitch
- Age at puberty
- Gestation Period
- Lenght of Pro-oestrus
- Lenght of Oestrus
- Time of ovulation
- Optimum time to breed
- Breeding Season
- Age at puberty - 8months
- Gestation Period - 64 days from fertile mating
- Lenght of pro-oestrus - 9 days
- Lenght of Oestrus - 9 days
- Time of ovulation - 2 days after LH surge
- Optimum time to breed - 3-6 days after LH surge (natural mating every 2-3days of standing oestrus
- Breeding Season - 2 seasons a year
Oestrogen such as oestradiol-17B
Where is it made
What does it to to the body
- Made by granulosa cells
- Causes Oestrous behaviour
- Preparation of tract for mating, pregnancy
What is the common causes for reproductive dysfunciont involving Pregnancy Loss
- Early Embryonic Loss
- 25-40% early Embryonic lost in farm species
- Causes
- Uterine infections
- Hormonal imbalance eg progesteron dificiency
- Maternal undernutrition (severe)
- Heat
- Stress, maternal disease
- Toxins eg urea
- Foetal Death
In a dog when can you see a skeleton in an xray?
From day 46
What size should the calipers measure on stallion Testies
8.5-11.5cms
How do you dect oestrus in a Sow?
- Vulval swelling and reddening 24-48hrs before standing oestrus
- Standing in responce to back pressure
- Teasing with the boar with nose to nose contact, sows ears will prick up, eyes will become restless, Honking.
- Go off feed
- Tacky vulval discharge
- Breed before ovulation
- Gestation = 115 days. 3months, 3weeks, 3days
- In oestrus for 2 days
In a mare you have 2 embryos what do you do?
- Day 14-16
- Crush the smaller one (Bilateral)
- Unilateral - separate and crush one
- Day 17-34
- Crush one
- Abort both with PG - can still cycle again
- Day 35-60
- Endometrial cups have formed (eCG) - (no more cycles for the season)
- Abort both with multiple PG injections
- Bilateral
- Crush one
- Day 61-90
- Most will abort if left
- Abort both with multiple PG injections
- Surgical removal if bilateral
- Day 91-150
- Most will abort
- After 90 days foetus has passed over pelvic ledge into abdomen
- Unilateral
- Transabdominal US-guided foetal cardiac puncture, inject KCL or procaine penicillin
Explain the reproductive cycle in a bitch and how it differece from other domestic animals
- Bitch in pro-oestrus for about 9 days then in oestrus for about 9 days (average)
- Can be difficult to determine on behavioral signs alone when she is in season, when she changes from pro-oestrus to oestrus
- LH surge happens about the time the bitch goes form pro-oestrus to oestrus
- Ovulation occurs approximately 2 days later
- Ovulation takes place sometime early in oestrus
- Bitch ovulates a primary oocyte compared to other species whihc ovulate a secondary oocyte
- This primary ooocyte requires 2-3 days after ovulation to mature ready for fertalisation
- Fertile period is soem 2 says after ovulation but there is no physical sign that indicates this exact time.
- Sperm can last up to 5 days in the bitch
What test could you do to ensure all of the ovary has been removed after a bitch/queen spey?
Blood test for Anti-Mullerian hormone
What are the 5 classes of follicles and explain
- Primordial - oocyte, without zona pellucida, one cell layer round
- Committed - start to grow, first slowly, develop zona pellucida, granulosa and thecal cells form. Local regulation of growth. Develop receptors for FSH and LH, but grow independently of these hormones.
- Gonadotrophin responsive - fluid filled antrum forms, growth slow then speeds up. Granulosa cells proliferate and become sensitive to FSH
- Gonadotrophin dependent - absolute requirement for FSH, stimulates enzymes and oestradiol produced. LH receptors also appear.
- Ovulatory - granulosa cells with large number ofr FSH and LH receptors, , large fluid-filled antrum, lots of oestradiol
What is the correct name for Vibrio?
Campylobacter fetus venerealis
What is the common causes for reproductive dysfunciont involving Anoestrus
- True Anoestrus
- Normal part of the cycle (eg Bitch)
- Seasonal: Mare long day breeder, ewe short day breeder
- Nurtitional : Poor energy in diet
- Lactational: Pregnancy steroids inhibit hypothalamus , sucking (+ undernutrition) inhibit tonic GnRH and LH secreation
- Aging
- Stress
- Abnormalities of Uterus, Ovaries :Ovairan hypoplasia, freemartinism
- Persistent production of progesterone ; Cystic ovaries, uterine disae (no PG0, pregnancy/pseudopregnancy/lost pregnancy, still have a CL - prolonged dioestrus
What are the anatomical protections of a mares uterus?
- Three seals
- Vulva
- Vestibulo-Vaginal Seal
- Cervix
- In oestrus the cervix is open
- If there is poor perineal conformation or other seals do not work properly, contamination with urine/faeces is possible
In a sow
- Age at puberty
- Gestation Period
- Lenght of Oestrus cycle
- Lenght of Oestrus
- Time of ovulation
- Breeding Season
- Age at puberty - 7months
- Gestation Period - 115days
- Lenght of Oestrus cycle - 21days
- Lenght of Oestrus - 2 days
- Time of ovulation - 36 hrs into oestrus
- Breeding Season - Polyoestrus all year
What happens to the granulosa cells once the follicle has ovulated?
- Once ovulated the granulosa cells become luteinized in responce to LH binding to receptors acquired by these cells late in the frollicular phase. These cells then develop into the corpus luteum (CL) and the cells proliferate and hypertrophy to fill in the follicular cavity.
What does the Luteal cells secrete?
Progesterone
How does inhibin work?
- It is produced within the mature granulosa cell and it inhibits the tonic release of gonadotrophins, so that while the dominant follicle can continue to grow after a certain point, other follicles will not get the stimulation of FSH and therefore will not develop.
- The increasing oestrogens also stimulate a final surge of LH which enables final maturation and ovulation.
What specific organisms can cause Post-Service endrometritis in a cow?
- Campylobacter fetus venerealis (Vibrio)
- Tritrichomonas foetus (Trich)
Veneral transmission during mating
Bulls generally asymptomatic carriers
Infection can be carried in semen at AI
Cause uterine inflammation, preventing conception or causing embrynic death
How can you tell a bitch will soon give birth?
- Check rectal temp, when it drops below 37oC parturition is usually within 24hrs
- Mammary development - time and degree of development depend on age, prior births (DDX - Pseudopregnancy in the bithc)
- Vulval Changes - swollen and softened
- Pelvic Changes - Ligaments relax
- Lose appetite
What happens if a pregnant mare aborts after day 45?
Probably wont cycle again this season due to the endometrial cups being formed.
How do you diagnose Cryptorchidism?
- Palpation, Ultrasound for presence of testis in scrotum
- Hormaonal tests for testosterone broduced by intra-abdominal testis; may need to stimulate testosterone production by using hormones eg drug with LH or GnRH activity.
Name the Artificial vaginas available for Stallions
- Missouri
- Colorado
- Hannover
- Roanoke
- Japanese
Progesterone
Where is it made?
What does it do?
- Made by the corpus luteum
- Hormone of pregnancy
- Decreases uterine motility
What are the two stages of the Bitch Oestrus cycle, how long do they last and what signs are displayed?
- Prooestrus
- average 9 days (5-20days)
- Blood stained discharge, swollen vulva, attractive to male but wont stand
- Oestrus
- Average 9 days (5-15days)
- Discharge clear/yellow, bitch will stand for dog, “flag” tail to one side
- Dioestrus: no longer interested in male, leteal period (65d pregnancy, 50-80d diestrus)
- Anoestrus: no ovarian activity at all 80-240days
The bitch ovulates a couple of days into oestrus, ovulates primary oocytes wich take 2 days to mature. Therefore breed around or after the time of ovulation.
How to you treat pyometra in
Cow
Mare
Dog
- Cow
- Cervix is often closed to to progesteron, retained CL so give PG used to cause luteolysis, myometrial contracton, uterine evacuation
- Intrauterine flush with saline, antiseptic or ABX
- Systemic antibiotics if required
- Mare
- Usually secondary to cervical adhesions and damage, preventing draining of fluid from uterus
- Retained CL distended uterus does not produce PF
- Prain purulent material, flush with saline, daily flush and recover fluid. (Oxytocin after flushing)
- PG to cause luteolysis and uterine contractions
- Often irreversible due to cervix damage, surgical hysterectomy for riding horse.
- Bitch
- Usually older bitches
- Following oestrus cycle upto 2-3months afterwards
- Endotoxaemic, polyuria/polydypsia
- Xray/US abdom, fluid distention of uterus, no foetuses
- Treatment
- Surgically remove uterus (complete OVH) with aggressive supportive therapy pre/post surgery
- Remove progesterone effects, Aglepristone (progesterone blocking drug)
- PG - Luteolytic and uterotonic however not registered for use in small animals and can have nasty side effects
- ABx to limit systemic illness
What hormones do granulosa cells
Respond to?
Produce?
- FSH - mainly
- Oestrogens and Inhibin
In a dog what are the three fractions of ejaculate and their volumes?
- Three fractions
- Presperm :
- Clear <1ml
- Sperm-rich
- 1-3ml cloudy
- Post sperm
- Clear up to 15ml
- Presperm :
What are some male reasons for not mating?
- Decreased libido
- Inability to mount
- Failure of erection
- Failure of intromission
how do you diagnose abortion?
- History, animals affected, stage of gestation
- Damn : serology (Paired) uterine/cervical swab/fluid for culture
- Placenta : gross appearance, histolgy, culture, amniotic fluid
- Foetus : serology, gross appearance, age, stage of development lesions, histolgy, lung, liver, kidney, brain, spleen, gut, skin. Culture stomach fluid, lung, liver
Where is LH and FSH released from?
Anterior Pituitary
What are some clincial signs of uterine disease
- Anoestrus
- Short
- Sycle
- Failure to conceive
- Early Embryonic Loss
- Abortion
- Post-Partum problems
Describe the fertalisation process
- Sperm travels up to the oviduct (approx 30mins in most species)
- Fertalisation happens in the ampulla of the oviduct
- Sperm
- Capacitation
- membrane altered, increased tail motility, sperm metabolism
- Acrosome reaction
- enzymes in acrosome activated, so they can penetrate the zona pellucida
- Capacitation
- Fusion of sperm activates oocyte which continues to final stage of meiosis
- Sperm and oocyte chromatin mix and recondense
- Chromosomes reaggregate to form diploid organism
In a Mare
- Age at puberty
- Gestation Period
- Lenght of Oestrus cycle
- Lenght of Oestrus
- Time of ovulation
- Optimum time to breed
- Breeding Season
- Age at puberty - 18months
- Gestation Period - 336 days
- Lenght of Oestrus cycle - 21 days
- Lenght of Oestrus - 5-6 days
- Time of Ovulation - 5th day of heat
- Optimum time to breed - 2nd - 5th day of heat, Follicle 35-40mm in diameter and soft
- Breeding Season - Spring and Summer (Long day breeders)
Cystic Ovarian Disease in Cows
Pathogenesis
Diagnosis
Treatment
- Pathogenesis
- Lack of LH, Stress and Negative energy balance at peak lactation
- Luteal (of luetal tissue) thick walled
- Follicular large and thin walled
- Diagnosis
- Behavious, Anoestrus (70-80%), Nymphomania, irregular and prolonged cycles (20-30%)
- Can be palpated but hard to tell between the two types
- Ultrasonography to determine thickness of wall
- Follicular - <3mm
- Treatment
- 60% spontaneously regress in the early post partum period
- Causing a LH surge should result in sufficient luteinisation of the cysts such that they then produce enough progesteron to cause normal feedback on the hypothalamus.
What oestrus detection methods are used for Mares ?
- Tend not to show oestrus behaviour to each other so regular teasing with a stallion is required.
- The mare in oestrus will be interested in the stallion and come up to him,
- Squat and urinate and evert the clitoris (known as winking)
- Breed before ovulation, when she has a large follicle (>40mm, soft) and is in heat.
Discuss the factors which can predispose or lead to utering infection in domestic animals
- Hormonal environment
- Oestrogen increases resistance to infection
- Progesteron decreases resistant
- Infectious organisms
- Bacteria
- Staph (skin)
- Strep (resp tract)
- Coliforms (faecal contamination
- Specific venereal pathogens
- Taylorella
- Campylobacter
- Brucella
- Viruses
- Herpes
- Pther
- Fungi
- Protozoa
- Tritrichomonas
- Bacteria
What tests can you do on a Bitch to ensure the optimum time for mating?
- Plasma Progesterone
- Vaginal Exfoliative Cytology - looking for cornified cells
- Behavioural signs
Explain Spring heat in mares
- Incresed light (photoperiod) kicks in GnRH which stimulates FSH
- Ovary responds by initiating follicular development
- Increased Oestrogens cause behavioural oestrus However because there is insufficient LH the follicles regress without ovulating.
- This process repeats 3-4 times until there is sufficient LH being made to cause the LH surge, follicular maturation and ovulation.
Using Ultrasound in a cow what stages can you diagnose pregnancy and age?
- Can detect from about 20days, very small amount of fluid spread throughout horns
- Day 22 - 6mm spot in allantois
- Day 28 - embryo 10mm long
- Day 38 - Embryo 20mm long
- Day58 - embryo about 55 mm long
- Little placentomes from about day 42
When does Brucella abortus abort?
- Mid gestation
- DX bacterial isolation eg fetal abomasal fluid, lung, placenta, uterine fluid, milk
- Zoonotic
How long is the Oestrous cycle in a Mare?
How long are they in Oestrus?
How long is the Luteal Phase?
- 21-22days
- In oestrus 5-6days, ovulate towards the end
- Luteal phase ~14days
For Anoestrus reproductive dysfunction describe the common causes
- No oestrus cycling, no behavioural oestrus
- Can be due to total reproductive quiescence, ovarian shut down, or due to the negative feedback of progesterone on the hypothalamus shutting down further cycles
Draw what an ultrasound of a mare’s foetus would be each week
When might you write a certificate of pregnancy for the mare?
Your client lives too far away for you to rectal the mare and asks about a blood test for pregnancy. At what stage of pregnancy would you test and for what?
- You can test for eCG (Pregnant Mare Serum Gonadotrophin) once the endometrial cups form around day 35.
- You wouldnt write a Pregnancy certificate until you test the urine for Oestrogen suplphate after day 100
Can Bull get be cured of Vibrio
- Young bulls can clear the infection
- Older bulls become lifelong persistent carriers
If the animal is not pregnant how does the cycle start again?
Explain the Structure of Sperm
What is Proestrus?
The period of follicular development before an animal is actually ready to be mated
List the disorders that can happen at parturition
- Dystocia
- Stillbirth
- Retained foetal membranes (Placenta)
- Infections
Explain the Process of Spermatogenesis
Spermatogonium
Spermatogonia
Spermatocyte
Spermatids
Spermatozoa
What is the sequellae of RFM?
- Endometritis
- Endotoxaemia
- Delayed return to service
- Delayed conception, poor conception
A client rings to tell you that their bitch has a green discharge but no puppies have been born. Should they worry?
- This is critical as the baby may no longer be getting oxygen from the mother. It is usually called the Meconium
Describe the methods of examination of the female reproductive tract
- External genitalia
- Vulva, conformation, placement, apposition of vulval lips, general perineal conformation especially in mares
- Check for size, swelling
- For breeding animal also examine mammary glands
- Vaginal Exam
- Should not contaminate tract, clean vulva throughly
- Palpation : digital exam of bitch larger animals can palpate whole vagina
- Speculum - sterile procedure, visualise
- Check for strictures, intact hymen, adhesions, abnormal growths, varicocoeles, tears etc
- Vaginal exfoliative cytology
- Endoscope
- Examination of the Cervix
- Can visualise via speculum to determine stage of oestrous cycle in mares.
- Oestrus : Soft, Dark pink and floppy
- Check after parturition for tears,adhesions
- Manually palpate per vagina, per rectum in large animals
- May visualise with endoscope - only way to see in the bitch.
- Can visualise via speculum to determine stage of oestrous cycle in mares.
- Examination of the uterus
- Uterine Palpation
- per rectum or transabdominally
- Palpate for tone, size, fluid etc
- Palpate both horns to the tips and body of uterus
- Palpable lesions include
- pyometra
- endometritis - thickened doughy pitting large cysts
- Palpate for signs of pregnancy
- Ultrasonography
- Per rectum in mares possible also in cows
- Scan from ovary to ovary along both horns and across body
- Look for luminal fluid, cysts, pregnancy, uterine folds, oedema etc
- Transabdominally (less resolution using 3.5MHz probe)
- Endometrial swabbing
- Sterile procedure to sample cells and organisms within uterus
- Large animals: pass through cervix
- Small animals: surgical procedure or via endoscopu
- Swab guarded or open
- Used for cytology or culture
- Endometrial Biopsy
- Piece of endometrium biopsied with jawed forceps
- Fix and stain, examine for inflammatory cells, organisms, glandular structures.
- Uterine Palpation
- Examination of the ovaries
- Transrectal palpation
- US examination : transrectal in large animals and transabdominal for small animals.
- Examination of the Oviduct
- Should be palpated especially in cows for adhesions, thickening and cysts. US can show lesions. Patency can be tested through the use of dyes.
- Hormonal Analysis
- Progesterone
- Useful to assay to determine if ovulation has occured but not definitive as a preg test.
- Oestrogens
- Oestrone sulphate is produced by foetus in pigs, horse and concentrations can indicate pregnancy and foetel viability. Sme can be tested in urine (Horses)
- Gonadotrophins
- eCG and hCG produced by placenta can be measured in blood or urine to test pregnancy
- Progesterone
What is the common causes for reproductive dysfunciont involving Failure to conceive
- Ovulatory FFailure : mares early in season, insufficient LH, Cows with cystic ovaries
- Fertilisation Failure