Reproductive Toxicants and Induced Abortions Flashcards
What 4 plant teratogens do we worry about in the cow?
Locoweed
Poison hemlock
Lupines
Tree tobacco
What 4 abortive plants do we worry about in the cow?
Locoweed
Nitrates
Ponderosa pine
Broomweed
What 3 plant substances cause infertility in the cow?
Locoweed
Fescue
Insecticide
When do we see poison hemlock come out?
Spring time
What does poison hemlock cause in calves?
“Crooked calf syndrome”
When during gestation does the dam have to ingest poison hemlock for it to have its teratogenic effect on the fetus?
Between 50-75 days
What are the 2 substances found in lupines that are teratogenic?
Anagyrine
Ammodendrine
When during gestation does the dam have to ingest lupines for it to have its teratogenic effect on the fetus?
Between 40-70 days.
What is interesting of lupines in small ruminants?
It’s not teratogenic in small ruminants.
How does tobacco affect the fetus?
Arthrogryposis of the forelimbs and curvature of the spine.
When during gestation does the dam have to ingest tobacco for it to have its teratogenic effect on the fetus?
Between 50-75 days.
What is the toxin in locoweed?
Swainsonine
“Ron Swanson goes loco”
What 3 things can locoweed cause?
Neurologic signs
Abortion
Fetal abnormalities
What toxic plant can animals get “hooked” on?
Locoweed
How long do animals need to consume locoweed before they get “hooked” on it?
4-6 weeks
What plant causes the most economic loss?
Locoweed
What s the toxin in ponderosa pine?
Isocupressic acid
What is the abortion rate for consumption of ponderosa pine?
Up to 50%
How long does a dam have to eat ponderosa pine for it to have it’s abortive effect?
Greater than 3 days.
What can be done to reduce ingestion of ponderosa pine?
Feeding corn silage
What are the 4 toxins produces by broomweed or snakeweed?
Monoterpenes
Diterpenes
Saponins
Oxygenated flavonol methy esters
What 2 things does consumption of broomweed or snakeweed cause?
Abortion
Retained fetal membranes
When do you see broomweed and snakeweed?
In the spring.
What produces the toxin associated with fescue?
A fungus (neotyphodium coenophialum)
What is the toxin associated with fesuce?
Ergovaline
What does ergovaline cause?
Peripheral vasoconstriction
What is “Summer Slump” in cattle, and what causes it?
Decreased reproduction/ infertility and decreased milk caused by ergovaline.
What 5 plants accumulate Nitrates?
Johnson grass Sudan grass Oats Wheat Corn
When do we see nitrates especially high?
During drought periods
What 3 things do we see when the dam ingests nitrates?
Fetal hypoxia (d/t methemoglobinemia)
Fetal death
Late gestation abortions
How do you diagnose nitrates as the cause of abortion?
Test ocular fluid of aborted fetuses.
What are 5 reasons to induce abortion in cattle?
Accidental breeding Pregnancy in feedlot heifer Fetal maceration Fetal mummification Hydrops condition
What are the 2 dropsical conditions?
Hydrallantois
Hydramnios
What is hydrallantois?
Abnormal accumulation of allantoic fluid during 5-20 day period of last trimester.
Which condition is more common, hydrallantois or hydramnios?
Hydrallantois.
What are the 3 steps to treating a dropsical condition?
Induce abortion
Slow drainage of fluid (over 24 hours)
Constant monitoring
What is the progesterone source in the cow for the first 150 days?
Luteal
What is the progesterone source in the cow between 150 and 250 days?
The placenta acts as an additional source.
What happens to the source of progesterone in the cow in the final month of pregnancy?
Placental origin declines while luteal P4 continues.
What are the 2 general drugs we use to induce abortion in the cow?
Prostaglandins (Estrumate, Lutalyse)
Corticosteroids (Dexamethasone)
How does PGF2a work to induce abortion?
Acts to cause luteolysis.
NOTE: Has no effect on placental P4 production
How do corticosteroids workto induce abortion?
Reduce placental P4 production
What do you need to know to help pick the drugs that you will use to induce abortion?
The stage of gestation.
NOTE: If you don’t know the stage of gestation, you can just use both PGF2a and corticosteroids.
What is the protocol for abortion in a cow that is between 5-150 days gestation?
Single injection of PGF2a
What is the protocol for abortion in a cow that is between 150 and 240 days gestation?
Remove ovarian AND placental sources of P4 with a combo of 25mg each of PGF2a and corticosteroids.
Abortion after how many days leads to retained fetal membranes in 80% of cows treated?
120 days
What are 3 indications for inducing abortion in a cow?
Severe udder edema
Vaginal Prolapse
Abnormal pregnancy (eg. hydrops)
What is the protocol for inducing parturition in a cow?
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.
