Hormonal Therapy

Question 1

what are prostaglandins?

Answer 1

20-carbon atom derivatives of fatty acids arachadonic acid and di-homo-gamma-linolenic acid

Question 2

what does PGF2alpha do?

Answer 2

luteolytic
causes regression of corpus luteum

Question 3

where is GnRH released?

Answer 3

hypothalamic surge and tonic centers

Question 4

where is oxytocin stored?

Answer 4

posterior lobe of pituitary

Question 5

what are the two components of luteinizing hormone and follicle stimulating hormone?

Answer 5

alpha subunit: identical
beta subunit: changes in each

Question 6

what is alizin/aglepristone?

Answer 6

progesterone antagonist

Question 7

when should you monitor estrus after giving a prostaglandin injection to a cow?

Answer 7

2-6 days after

Question 8

is prostaglandin an effective drug for short-cycling sows?

Answer 8

no: CL not responsive until days 12-14 and naturally lyses at day 15

Question 9

what would you use to suppress estrus in a mare?

Answer 9

altrenogest/regumate (brand for horses)
alternative brand for sows, same drug

Question 10

how would you stimulate onset of first estrus in prepubertal gilts?

Answer 10

PG600
boar exposure
travel
combination

Question 11

what can you use to synchronize estrus in weaned sows?

Answer 11

check for heat 4-6 days post weaning
triptorelin
based on weaning time

Question 12

what can you use to sychronize estrus in pubertal and cyclic gilts?

Answer 12

progesterone
PG600
GnRH
triptorelin

Question 13

is a single dose of prostaglandin effective at inducing abortion in a mare after day 40?

Answer 13

no
endometrial cups have been formed

Question 14

what are thee biochemical classifications of hormone therapy?

Answer 14

peptides
glycoproteins
steroids
prostaglandins

Question 15

which drugs are neuropeptides?

Answer 15

GnRH
oxytocin

Question 16

what are the glycoproteins?

Answer 16

FSH
LH
eCG/PMSG
hCG
AMH

Question 17

what do prostaglandins play a critical role in?

Answer 17

ovulation
passage of early embryo through oviduct
intrauterine migration of conceptus during maternal recognition of pregnancy- mare
cervical relaxation and uterine contraction during parturition

Question 18

which prostaglandins are important in reproduction?

Answer 18

PGF
PGE
PGF2alpha luteolytic: regression CL

Question 19

what are steroid hormones derived from?

Answer 19

cholesterol

Question 20

where are steroid hormones produced?

Answer 20

adrenal cortex and gonads

Question 21

which steroid hormones are responsible for sexual promotion?

Answer 21

estrogen
progesterone
testosterone

Question 22

what is regu-mate/altrenogest?

Answer 22

synthetic progestin

Question 23

what is melengestrol acetate used for?

Answer 23

growth promoting feed additive cattle
estrus suppression heifers for slaughter or breeding management

Question 24

what are some problems with megestrol acetate?

Answer 24

irritating when injected
may induce endometrial hyperplasia/pyometra in bitch/queen
decreases resistance to bacteria and closes cervix: may lead to metritis
exacerbates mammary tumors in bitch
mastitis

Question 25

what is GnRH released by?

Answer 25

hypothalamic surge and tonic centers

Question 26

where is oxytocin synthesized?

Answer 26

posterior lobe of pituitary

Question 27

what is the main side effect of GnRH/deslorelin?

Answer 27

injection site swelling

Question 28

what is triptorelin acetate/GnRH used for?

Answer 28

intravaginal use for weaned sows for single fixed time AI

Question 29

what do you need to have uterine effects of oxytocin?

Answer 29

estrogen priming prior to oxytocin not in mares

Question 30

are FSH and LH antigenic?

Answer 30

yes

Question 31

what are LH and FSH available as?

Answer 31

pituitary, serum, urine extracts

Question 32

what is human chorionic gonadotropin/

Answer 32

LH analog used for LH activity glycoprotein hormone

Question 33

what is a brand name of human chorionic gonadotropin?

Answer 33

PG600

Question 34

what is porcine pituitary-derived follicle stimulating hormone?

Answer 34

glycoprotein hormone only FSH product approved by FDA from swine pituitary, usually has LH contamination

Question 35

what does a progesterone antagonist do?

Answer 35

competitive antagonism of progesterone and blocking the hormone responsible for implantation and pregnancy maintenance

Question 36

how can you terminate a pregnancy in a sheep?

Answer 36

cloprostenol or dinoprost before 55 days (CL maintains until 50-60 days) dexamethasone after 55 days

Question 37

what can you give a cow to induce parturition?

Answer 37

dexamethasone flumethasone