Tetatogenic inheritance

Question 1

what is tetraogenesis

Answer 1

-abnormal development influenced by drugs, viruses, chemicals, radiation, inutero
-therefore a mammalian phenomenon
-environmental influenced during gestation

Question 2

examples of tetraogenesis

Answer 2

-twisted leg (cattle)
-cyclopia (lambs)
-cleft pallet (cattle, dogs)
-heart defects (sheep)

Question 3

what is the biological threshold

Answer 3

-developmental processes that occur on a fixed schedule
-at a fixed period in gestation, disruptions or delays cause that organ to be incompletely developed

Question 4

neural tube closure in humans

Answer 4

-start with your neural plate flat open and you anterotary and postouitary side
-neural groove somites (folding)
-then develop neural fold (starts to zip/close)
-completely closes and turns into neural tube

Question 5

what happens if ends dont close in neural tube closure

Answer 5

spina bifida

Question 6

what is spina bifida

Answer 6

-neural tube doesnt close by day 25 in gestation
-more common in cockasians and hispanic
-but environmental factors play a big role

Question 7

causes spinal bifida risks

Answer 7

-maternal folic acid deficiency
-exposure to high temperatures in early pregnancy (pronged fever or hot tub use)
-maternal insulin dependent diabetes
-medications (anti seizure)

Question 8

cleft lip and palate

Answer 8

-in utero development of face at 7-9wks (cattle)
-fixed time period of facial development
-delay (fever, virus)
-face not finished
-failed fusion of nasal process

-more common in bulldog breeds (genetic component?)
-maybe multifactorial but also congenital so not sure where to classify
-more common when more then one child effected
-drugs due to illness
-smoking

Question 9

teratogenesis factors

Answer 9

-genetic background:
-predisposition to the teratogen
-predisposition to the malformation

-exposure:
-time & length
-dose

Question 10

teratogenesis generlizations

Answer 10

-animal pregnant or lactating at time of exposure (rarely through male)
-few effects last from prior conception
-most effects have a two week delay
-“preimplantation” a “safe” period or embryo dies
-primarly congenital defects

Question 11

developmental stage at time of exposure

Answer 11

blastocyst-lethality
organogenesis-structural defect
histogenesis-microscopic changes
growth-stunting

Question 12

access of the teratogenic agent

Answer 12

-direct:
-radiation
-microwave
-ultrasound

-indirect
-maternal blood via the placenta (alters absorption and doses)

Question 13

physical teratogens

Answer 13

-temperature:
-fever, overheating, hypothermia
-ultrasound:
-high frequency sound wave used to direct preg test but has possibility of thermal damage
-electromagnetic field:
-power towers
-appears more bone abnormalities but not 100% confirmed or denied

Question 14

biological teratognes

Answer 14

-malnutrition
-viruses
-disease
-twinning

Question 15

different types of malnutrition teratogens

Answer 15

-malnutritioin
-specific dietary deficiencies
-specific foods

Question 16

malnutrition teratogen

Answer 16

-generally low birth weigh

Question 17

specific dietary deficiencies

Answer 17

twisted legs (arthogruposis)
due to manganese deficencies

Question 18

specific teratogen foods

Answer 18

-locoweed
-lupine
-veratrum spp
-sudan grass
-tobacco stocks

Question 19

lupine

Answer 19

-grows in cypresshills region
-crooked calf disease
-high conc of alkaloids

Question 20

locoweed

Answer 20

abortions+malformations in sheep and cattle

Question 21

vetatrum spp

Answer 21

-grows in foot hills
-cyclopia in lambs if ewes ingest about day 14 of gestation
-poison of the rizomes on plant

Question 22

sudan grass

Answer 22

-arthrogryposis in horses
-also cows but not as severe
-not native to NA

Question 23

tobacco stocks

Answer 23

-byproduct of the cig industry
-when fed to pigs piglets developed stiff and swollen joints
-and a lot of stillborn
tetarogen=nicotine

Question 24

biological teratogen: viruses (bovine viral diarrhea)

Answer 24

-abortion
-CNS damage
-persistent in infected calves
-weak small

Question 25

biological teratogen: disease-diabeates

Answer 25

-diabetes in dogs
-spikes and dips in glucose prob the teratogen
-babies born from diabetics= higher congenital defects (spinabifida)

Question 26

biological teratogen: twinning mortality

Answer 26

-twin mortality:
-horses (draft twin more easy)
-90% abort
-~50% of live births survive
-cattle: 30-40% abort

Question 27

biological teratogen twin morbidity

Answer 27

-premature birth typical
-low birth weigh (~75% of average)
-respiratory problems (under developed lungs)

-positioning effects
-limb deformities

-freemartinism

Question 28

chemical teratogens

Answer 28

-food additives
-pollutants
-drugs

Question 29

chemical teratogens: food additives

Answer 29

-ethoxyguin (dog food preservative)
-skin problems
-abortion?
-animal feed additive
-reduction of use- several countries do now allow use

Question 30

chemical teratogens: pollutants

Answer 30

sour gas
-increased sulfur because plants take it up which decreases selenium
-white muscle disease in calves

Question 31

chemical teratogens: drugs (wormers)

Answer 31

-albendazole
-anury- agenesis of the tail, anus, CNS in cattle & sheep
-rumental ok in lactation sheep and animals
-ivermectin found to be ok during gestation

Question 32

chemical teratogens: drugs (antibiotics)

Answer 32

-chloramphenicol
-can not be used in food producing animals
-aplastic anemia in humans (bone marrow damage form milk)
-would this occur in pups?
-regulations are made to protect humans not animals

Question 33

chemical teratogens: drugs (medications)

Answer 33

-prescribes for seizures
-can cause a broad spectrum of major defects (5/77 human pregnancies)
-and mildly depressed congenital and language abillities
-but… frequent seizures can cause hypoxia and fetal distress and/or defects