Cow Infertility and Reproductive Diseases

Question 1

What are the 4 types of reproductive failure in cows?

Answer 1

1. Failure to ovulate after estrus
2. Failure of fertilization
3. Embryonic death
4. Fetal death

Question 2

Define pregnancy wastage

Answer 2

Combined embryonic, fetal and neonatal deaths
-most losses occur in embryonic stage prior to maternal recognition

Question 3

Define infertility

Answer 3

Failure of fertilization to occur, results in a normal cycle length

Question 4

If embryonic loss occurs after day 16, will cycle length be normal or abnormal?

Answer 4

Abnormal

Question 5

What is late embryonic loss?

Answer 5

Losses between 30-42 days
-results in abnormal cycle length but no physical signs of abortion

Question 6

Define fetal death/abortion

Answer 6

Losses after 42 days
-accompanied by physical signs of abortion

Question 7

Define early embryonic loss

Answer 7

Losses before day 17 of pregnancy (70% of embryonic losses)
- cannot distinguish from infertility

Question 8

What receptor does interferon tau act on to stimulate maternal recognition of pregnancy?

Answer 8

Blocks Estrogen receptor ER alpha which then results in blockage of oxytocin receptors leading to maternal recognition

Question 9

What age group of cows is more likely to have late term abortions?

Answer 9

Heifers

Question 10

What can occur during heavy lactation which affects cows ability to concieve?

Answer 10

Low progesterone levels

Question 11

How does low progesterone affect high lactating dairy cows from days 1-7, day 8-27, day 38-60 and day 60-90

Answer 11

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

Question 12

How do you know if a cow may have an infertility issue?

Answer 12

Shes a repeat breeder
-could also be due to poor estrus detection, improper AI timing or handling

Question 13

What are some important history questions when working up an infertility case?

Answer 13

Vaccination schedule, percentage of herd affected, concurrent clinical signs, husbandry

Question 14

Which two bacteria are known for causing infertility in females?

Answer 14

Trichomoniasis and campylobacteriosis

Question 15

What does trichomoniasis cause in cows?

Answer 15

Cows coming back into heat and low preg rates
- diagnose by checking bull (PCR of smegma)

Question 16

What does campylobacteriosis cause in cows?

Answer 16

Inflammation of the uterus, mucopurulent endometritis
-diagnose with rtPCR of cervical swab or wash

Question 17

What do mollicute infections (ureaplasma/myocplasma) result in in cows?

Answer 17

vulvovaginitis, cervicitis, emdometritis, salpingitis, abortions, infertility due to reluctance to breed

Question 18

What disease does bovine herpesvirus 1.2B cause in cows?

Answer 18

Infectious pustular vulvovaginitis, endometritis, and oophoritis

Question 19

What is the treatment for bovine herpesvirus in cows?

Answer 19

spontaneous recovery after 2 weeks

Question 20

What urine acquired bacteria can lead to abortion storms and infertility?

Answer 20

Leptospirosis

Question 21

Name an opportunistic pathogen which can cause degeneration of embryos due to adherence to the zona pelllucida?

Answer 21

Histophilus somnus

Question 22

How does BVDV contribute to infertility?

Answer 22

It can lead to oophoritis, salpingitis, hormone alteration

Question 23

Describe endometritis and how it contributes to infertility.

Answer 23

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

Question 24

Describe the grades of endometritis from 0-3

Answer 24

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)

Question 25

When is endometritis considered clinical?

Answer 25

When it is a grade 3 21 days or more after parturition or score 2 26 days postpartum

Question 26

How do you diagnose subclinical endometritis?

Answer 26

Endometrial cytology or biopsy
- >18% neutrophils in uterine cytology 20-33 days post partum or >10% neutrophils 34-47 days post partum

Question 27

How do you treat a pyometra?

Answer 27

Prostaglandins and time

Question 28

How is a pyo different than endometritis?

Answer 28

No thickening of the uterine lining

Question 29

What is the prognosis for mucometra/hydrometra in heifers?

Answer 29

Poor- likely congenital

Question 30

What is the most common tumor associated with the repro tract of cows?

Answer 30

Uterine lymphosarcoma
-followed by uterine/vaginal carcinoma, leiomyoma and granulosa cell tumors

Question 31

What is the pathophysiology behind ovarian follicular cysts?

Answer 31

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

Question 32

What do you do about ovarian follicular cysts?

Answer 32

GnRH agonist or CIDR to restore receptor responsiveness to estradiol in the hypothalamus
-essentially start an ovsynch protocol

Question 33

How does heat stress affect fertility?

Answer 33

It declines once rectal temp reaches 102.2
-can be affected from 15-19 weeks before ovulation to 2-3 days after ovulation

Question 34

What type of toxicants can affect fertility?

Answer 34

Phytoestrogens, endocrine disrupting compounds, endophyte infected tall fescue

Question 35

What percent of heterosexual twin births are affected by freemartinism?

Answer 35

92%
-due to exposure of female fetus to AMH

Question 36

What is the most commonly recognized non-inflammatory condition resulting in infertility involving the tubular repro tract in the bovine?

Answer 36

Freemartinism

Question 37

What are the signs of freemartinism?

Answer 37

Small vulva, increased anogenital distance, enlarged clot, vestigial or masculinization of ovaries, short vagina

Question 38

What can incomplete fusion of the paramesonephric ducts result in?

Answer 38

Vaginal band, double external cervical os, uterine didelphys