Reproductive Toxicants and Induced Abortions

Question 1

What 4 plant teratogens do we worry about in the cow?

Answer 1

Locoweed
Poison hemlock
Lupines
Tree tobacco

Question 2

What 4 abortive plants do we worry about in the cow?

Answer 2

Locoweed
Nitrates
Ponderosa pine
Broomweed

Question 3

What 3 plant substances cause infertility in the cow?

Answer 3

Locoweed
Fescue
Insecticide

Question 4

When do we see poison hemlock come out?

Answer 4

Spring time

Question 5

What does poison hemlock cause in calves?

Answer 5

“Crooked calf syndrome”

Question 6

When during gestation does the dam have to ingest poison hemlock for it to have its teratogenic effect on the fetus?

Answer 6

Between 50-75 days

Question 7

What are the 2 substances found in lupines that are teratogenic?

Answer 7

Anagyrine

Ammodendrine

Question 8

When during gestation does the dam have to ingest lupines for it to have its teratogenic effect on the fetus?

Answer 8

Between 40-70 days.

Question 9

What is interesting of lupines in small ruminants?

Answer 9

It’s not teratogenic in small ruminants.

Question 10

How does tobacco affect the fetus?

Answer 10

Arthrogryposis of the forelimbs and curvature of the spine.

Question 11

When during gestation does the dam have to ingest tobacco for it to have its teratogenic effect on the fetus?

Answer 11

Between 50-75 days.

Question 12

What is the toxin in locoweed?

Answer 12

Swainsonine

“Ron Swanson goes loco”

Question 13

What 3 things can locoweed cause?

Answer 13

Neurologic signs
Abortion
Fetal abnormalities

Question 14

What toxic plant can animals get “hooked” on?

Answer 14

Locoweed

Question 15

How long do animals need to consume locoweed before they get “hooked” on it?

Answer 15

4-6 weeks

Question 16

What plant causes the most economic loss?

Answer 16

Locoweed

Question 17

What s the toxin in ponderosa pine?

Answer 17

Isocupressic acid

Question 18

What is the abortion rate for consumption of ponderosa pine?

Answer 18

Up to 50%

Question 19

How long does a dam have to eat ponderosa pine for it to have it’s abortive effect?

Answer 19

Greater than 3 days.

Question 20

What can be done to reduce ingestion of ponderosa pine?

Answer 20

Feeding corn silage

Question 21

What are the 4 toxins produces by broomweed or snakeweed?

Answer 21

Monoterpenes
Diterpenes
Saponins
Oxygenated flavonol methy esters

Question 22

What 2 things does consumption of broomweed or snakeweed cause?

Answer 22

Abortion

Retained fetal membranes

Question 23

When do you see broomweed and snakeweed?

Answer 23

In the spring.

Question 24

What produces the toxin associated with fescue?

Answer 24

A fungus (neotyphodium coenophialum)

Question 25

What is the toxin associated with fesuce?

Answer 25

Ergovaline

Question 26

What does ergovaline cause?

Answer 26

Peripheral vasoconstriction

Question 27

What is “Summer Slump” in cattle, and what causes it?

Answer 27

Decreased reproduction/ infertility and decreased milk caused by ergovaline.

Question 28

What 5 plants accumulate Nitrates?

Answer 28

Johnson grass
Sudan grass
Oats
Wheat
Corn

Question 29

When do we see nitrates especially high?

Answer 29

During drought periods

Question 30

What 3 things do we see when the dam ingests nitrates?

Answer 30

Fetal hypoxia (d/t methemoglobinemia)
Fetal death
Late gestation abortions

Question 31

How do you diagnose nitrates as the cause of abortion?

Answer 31

Test ocular fluid of aborted fetuses.

Question 32

What are 5 reasons to induce abortion in cattle?

Answer 32

Accidental breeding
Pregnancy in feedlot heifer
Fetal maceration
Fetal mummification
Hydrops condition

Question 33

What are the 2 dropsical conditions?

Answer 33

Hydrallantois

Hydramnios

Question 34

What is hydrallantois?

Answer 34

Abnormal accumulation of allantoic fluid during 5-20 day period of last trimester.

Question 35

Which condition is more common, hydrallantois or hydramnios?

Answer 35

Hydrallantois.

Question 36

What are the 3 steps to treating a dropsical condition?

Answer 36

Induce abortion
Slow drainage of fluid (over 24 hours)
Constant monitoring

Question 37

What is the progesterone source in the cow for the first 150 days?

Answer 37

Luteal

Question 38

What is the progesterone source in the cow between 150 and 250 days?

Answer 38

The placenta acts as an additional source.

Question 39

What happens to the source of progesterone in the cow in the final month of pregnancy?

Answer 39

Placental origin declines while luteal P4 continues.

Question 40

What are the 2 general drugs we use to induce abortion in the cow?

Answer 40

Prostaglandins (Estrumate, Lutalyse)

Corticosteroids (Dexamethasone)

Question 41

How does PGF2a work to induce abortion?

Answer 41

Acts to cause luteolysis.

NOTE: Has no effect on placental P4 production

Question 42

How do corticosteroids workto induce abortion?

Answer 42

Reduce placental P4 production

Question 43

What do you need to know to help pick the drugs that you will use to induce abortion?

Answer 43

The stage of gestation.

NOTE: If you don’t know the stage of gestation, you can just use both PGF2a and corticosteroids.

Question 44

What is the protocol for abortion in a cow that is between 5-150 days gestation?

Answer 44

Single injection of PGF2a

Question 45

What is the protocol for abortion in a cow that is between 150 and 240 days gestation?

Answer 45

Remove ovarian AND placental sources of P4 with a combo of 25mg each of PGF2a and corticosteroids.

Question 46

Abortion after how many days leads to retained fetal membranes in 80% of cows treated?

Answer 46

120 days

Question 47

What are 3 indications for inducing abortion in a cow?

Answer 47

Severe udder edema
Vaginal Prolapse
Abnormal pregnancy (eg. hydrops)

Question 48

What is the protocol for inducing parturition in a cow?

Answer 48

Best protocol is 25mg each of PGF2a and dexamethasone. Reliable delivery within 40 hours

NOTE: You could just give PGF2a alone to induce parturition within 2-3 days.