Cow Infertility and Reproductive Diseases Flashcards
What are the 4 types of reproductive failure in cows?
- Failure to ovulate after estrus
- Failure of fertilization
- Embryonic death
- Fetal death
Define pregnancy wastage
Combined embryonic, fetal and neonatal deaths
-most losses occur in embryonic stage prior to maternal recognition
Define infertility
Failure of fertilization to occur, results in a normal cycle length
If embryonic loss occurs after day 16, will cycle length be normal or abnormal?
Abnormal
What is late embryonic loss?
Losses between 30-42 days
-results in abnormal cycle length but no physical signs of abortion
Define fetal death/abortion
Losses after 42 days
-accompanied by physical signs of abortion
Define early embryonic loss
Losses before day 17 of pregnancy (70% of embryonic losses)
- cannot distinguish from infertility
What receptor does interferon tau act on to stimulate maternal recognition of pregnancy?
Blocks Estrogen receptor ER alpha which then results in blockage of oxytocin receptors leading to maternal recognition
What age group of cows is more likely to have late term abortions?
Heifers
What can occur during heavy lactation which affects cows ability to concieve?
Low progesterone levels
How does low progesterone affect high lactating dairy cows from days 1-7, day 8-27, day 38-60 and day 60-90
1-7: affects oocyte quality
8-27: ill timed elongation, histotroph deficiency
28-60: affects placentome growth and vascular development
60-90: can result in unilateral twins
How do you know if a cow may have an infertility issue?
Shes a repeat breeder
-could also be due to poor estrus detection, improper AI timing or handling
What are some important history questions when working up an infertility case?
Vaccination schedule, percentage of herd affected, concurrent clinical signs, husbandry
Which two bacteria are known for causing infertility in females?
Trichomoniasis and campylobacteriosis
What does trichomoniasis cause in cows?
Cows coming back into heat and low preg rates
- diagnose by checking bull (PCR of smegma)
What does campylobacteriosis cause in cows?
Inflammation of the uterus, mucopurulent endometritis
-diagnose with rtPCR of cervical swab or wash
What do mollicute infections (ureaplasma/myocplasma) result in in cows?
vulvovaginitis, cervicitis, emdometritis, salpingitis, abortions, infertility due to reluctance to breed
What disease does bovine herpesvirus 1.2B cause in cows?
Infectious pustular vulvovaginitis, endometritis, and oophoritis
What is the treatment for bovine herpesvirus in cows?
spontaneous recovery after 2 weeks
What urine acquired bacteria can lead to abortion storms and infertility?
Leptospirosis
Name an opportunistic pathogen which can cause degeneration of embryos due to adherence to the zona pelllucida?
Histophilus somnus
How does BVDV contribute to infertility?
It can lead to oophoritis, salpingitis, hormone alteration
Describe endometritis and how it contributes to infertility.
It often follows parturition, copulation or AI
-uterus may be normal on palpation and these cows are rarely systemically affected (prulent exudate=clinical)
-decreases first-service preg rates
Describe the grades of endometritis from 0-3
0: clear or transluscent mucous
1: mucous containing flecks of white or off white pus
2: mucopurulent exudate containing <50% white or off white mucopurulent material
3: exudate containing >50% purulent material (white, yellow or sanguinous)
When is endometritis considered clinical?
When it is a grade 3 21 days or more after parturition or score 2 26 days postpartum
How do you diagnose subclinical endometritis?
Endometrial cytology or biopsy
- >18% neutrophils in uterine cytology 20-33 days post partum or >10% neutrophils 34-47 days post partum
How do you treat a pyometra?
Prostaglandins and time
How is a pyo different than endometritis?
No thickening of the uterine lining
What is the prognosis for mucometra/hydrometra in heifers?
Poor- likely congenital
What is the most common tumor associated with the repro tract of cows?
Uterine lymphosarcoma
-followed by uterine/vaginal carcinoma, leiomyoma and granulosa cell tumors
What is the pathophysiology behind ovarian follicular cysts?
Persistent anovulatory follicles that persists in the absence of a CL
-occurs due to lack of LH surge when follicle reaches ovulatory size
-causes calving interval to be about 50 days longer
What do you do about ovarian follicular cysts?
GnRH agonist or CIDR to restore receptor responsiveness to estradiol in the hypothalamus
-essentially start an ovsynch protocol
How does heat stress affect fertility?
It declines once rectal temp reaches 102.2
-can be affected from 15-19 weeks before ovulation to 2-3 days after ovulation
What type of toxicants can affect fertility?
Phytoestrogens, endocrine disrupting compounds, endophyte infected tall fescue
What percent of heterosexual twin births are affected by freemartinism?
92%
-due to exposure of female fetus to AMH
What is the most commonly recognized non-inflammatory condition resulting in infertility involving the tubular repro tract in the bovine?
Freemartinism
What are the signs of freemartinism?
Small vulva, increased anogenital distance, enlarged clot, vestigial or masculinization of ovaries, short vagina
What can incomplete fusion of the paramesonephric ducts result in?
Vaginal band, double external cervical os, uterine didelphys
