Pharmacology hormones and reproduction, etc Flashcards
(40 cards)
List endocrine glands
pituitary
adrenals
thyroid
ovaries /testicles
pancreas
kidneys.
Some factors that influence the hypothalamus are
Odors
Sounds
Sights
Stress
Temperature
Photoperiod (amount of time the animal is exposed to light)
Hormonal feedback
The hypothalamus releases substances that stimulate (related to endocrine system)
the pituitary gland to release trophic (growth-type) hormones, which travel through the blood to various organs. The organs are then stimulated to release other hormones or perform other actions
Negative feedback
Where high levels of hormone decrease the activity of the hypothalamus.
Positive feedback
Low levels of the hormone cause increased activity of the hypothalamus.
neurohormonal reflex (reproduction)
Applies to the release of oxytocin caused by milking, birth, or sensory stimuli associated with milking.
Four phases of reproductive system
Proestrus
Estrus
Diestrus
Anestrus
gonadotropin releasing hormone
(GnRH).
Causes the release follicle stimulating hormone (FSH) and luteinizing hormone (LH).
control the estrous cycles in animals.
Used to treat cystic ovaries in cattle
follicle stimulating hormone
FSH
causes a follicle to form, and this follicle begins to release estrogen
Estrogen
is a hormone that causes the body to transition from proestrus to estrus.
negatively feeds back to the estrogen
increase uterine tones
treats persistent corpus luteums in cattle.
used to help expel retained placentas or to induce abortion
Examples include estradiol and diethylstilbestrol (DES)
Liver
luteinizing hormone
LH
causes the mature follicle to ovulate and begin to form a corpus luteum.
corpus luteum
Begins to release progesterone and starts the cycle into diestrus.
the corpus luteum helps maintain the pregnancy
Progesterone
Growth producing hormone
prepares the uterus for reproduction and also decreases the production of GnRH through negative feedback.
Processed by liver
Gonadotropins
drugs that act like GnRH, LH, or FSH
FSH-p
the p is for pituitary) is used for superovulation and to help breed animals outside of their natural breeding seasons.
used in embryo transfer (ET) programs
Female hormone physiology
hypothalamus releases gonadotropin releasing hormone (GnRH).
causes the pituitary gland to release follicle stimulating hormone and luteinizing hormone,
FSH causes a follicle to form, and begins to
release estrogen.
the body to transitions from proestrus to estrus.
The animal shows signs of heat.
if not fertilized LH causes the mature follicle to ovulate and
begin to form a corpus luteum (ovary).
corpus luteum begins to release progesterone and starts the cycle into diestrus.
Progesterone prepares the uterus for reproduction and also decreases the production of GnRH through negative feedback
Androgens
Male sex hormones and help promote weight gain, red blood cell formation, and tissue anabolism (or growth).
Can help prevent estrus in female dogs.
In horses, they’re sometimes used to help synchronize breeding.
Androgens are regulated as Class III controlled substances, due to their potential for abuse by people.
Processed by the liver
Progestins
have the same effects as progesterone
Prostaglandins
Used to help abort pregnancies, induce parturition (giving birth), or treat pyometra.
Processed by the liver
Bonus - don’t need to do this: Prostaglandins have “prost” as part of their name and include dinoprost tromethamine and cloprostenol sodium.
To help induce labor, aid in the delivery of the newborn, or to help clear the uterus of fluids after birth you can give_____ And it is processed by
Oxytocin
Liver and kidneys
The thyroid gland is involved with many bodily processes, including the following:
Heart rate
Body temperature
Metabolic rate
Metabolism
Skin condition
Thyroid gland hormones
convert iodine into two active hormones, T3 and T4.
T3 is the active form of the hormone, whereas T4 is the inactive form
Hypothyroid animals treatment
supplement the diet of the animal with synthetic T4, (example is levothyroxine).
T4 is much cheaper than T3 and is usually readily converted to T3 in the body.
Some animals lack the enzyme to convert T4 to T3 and will need supplementation with T3 itself, but this phenomenon isn’t common.
Hyperthyroid animals treatment
require a drug that blocks the formation of thyroid hormones.
Radioactive iodine is another treatment that involves an injection taken up into the thyroid gland.
–The radioactivity destroys the thyroid tissue
Surgical removal of a thyroid gland is possible if only one gland is affected,
–hyperthyroid cats can be poor surgical candidates if the disease is advanced.