sexual behavior Flashcards
true/false: sexual behavior is one of the weakest “drive” in animals
false: strongest
adequate ______ in breeding animals
libido
what happens when promoting opportunity for mating to occur?
survival of the fittest
if we have improvements in animal husbandry then why do we still see problems with breeding programs?
◼ Seasonal breeders
◼ Artificial lighting
◼ Poor libido
◼ Mate selection preferences
when an animal has poor libido, what is an alternative for mating?
AI
what are the 3 stages of sexual behavior
- precopulatory- proceptive
- copulatory- receptive
- postcopulatory- refractory
what are some things that happen precopulatory?
search for sexual partner courtship sexual arousal sexual activity of female - estrus males - potentially anytime
who is courtship initiated by?
the female
what are signs that courtship may be intiated
◼ Pheromones
◼ Vocalization
◼ Increased physical activity
◼ Postural changes
what can cause a more aggressive courtship by the male?
Mounting activity in cattle
◼ Initiate courtship behavior in cattle
list identification of sexual partner
◼ Olfactory
◼ Visual
◼ Auditory
◼ Tactile
how can you tell a female is coming into estrus?
Show increased physical activity: ◼ Locomotion ◼ Milling around ◼ Increased phonation ◼ Agonistic behavior towards other females
Marked increased activity at time of ovulation
Series of highly specific courtship behaviors begin:
◼ Sniffing of vulva ◼ Urination in presence of male ◼ Flehmen ◼ Chin resting ◼ Circling ◼ Increased phonation
what is the flehmen response?
Behavior facilitates transfer of pheromones & other scents into the vomeronasal organ (VNO, or Jacobson’s organ)
where is the vomeronasal organ (VNO, or Jacobson’s organ) located at?
Located above the roof of the mouth via a duct which exits just behind the front teeth of the animal
what is the duct which exits just behind the front teeth of the animal
nasopalantine duct
what is lordosis?
Mating posture by estrus female
◼ Sows
◼ Cats
what does lordosis trigger and what is it associated with?
◼ Triggers significant sexual arousal by male
◼ Associated with willingness to mate
what is copulatory characterized by?
Mounting, intromission, ejaculation
what are examples of short copulators
bull
ram
what is an example of sustained copulators
boar
what is an example of an intermediate copulator
stallion
define intromission
Entrance of the penis into vagina
define ejaculation
Expulsion of semen into female reproductive tract
define copulation
◼ Degree of learning –male
◼ Past sexual experience important
what is postcopulatory characterized by?
◼ Dismount, refractory period
◼ Male, female or both will not engage in another period of copulatory behavior
define the refractory period of postcopulation
Time during which a second copulation will not take place
what are behaviors of postcopulatory
Gentle grooming, nuzzling, vocal emissions
list the factors that sexual behavior depends on
◼ Physiological
◼ Environmental
◼ Psychological
how can physiological, environmental, psychological factors be categorized?
- Genetic sex of animal
- Perinatal organization of hormones
- Past social & sexual experiences
- Adult actions of hormones & anatomical status
- Attractiveness of potential mate
- External environment
when is the sex of the animal determined and what develops
conception
ovaries or testes develop
when is sexual behavior programmed?
during prenatal development
when is the brain programmed to be either male or female?
during embryogenesis
early embryo is ______ with regard to sex
neutral
when does the brain become feminized?
when there is influence of extremely limited quantities of estradiol
define feminization
development of female-like behavior
what is the role of α-fetoprotein produced during development?
prevents (binds) estradiol from crossing BBB & entering brain
during development why does the brain become fully feminized?
because it has not been exposed to estrogen
α-fetoprotein does not bind _________, which can do what?
testosterone
which can cross BBB and be converted to estradiol
what causes masculinization of the brain in developing males?
high concentration of estradiol
developing males results in the ability of embryo to develop male-like behavior ________
postnatally
although dogs castrated at birth had penes that were very small, all dogs still do what?
urinate in a masculine posture
what was the response of dogs castrated at birth to exogenous testosterone from dogs castrated as adults?
no different response to intact dogs
what happened with dogs castrated at birth in terms of exposure to estrus females?
attracted and mounted them, underdeveloped external genitalia prohibited normal intromission
what happened with dogs castrated at birth when treated with estrogen as adults?
◼ Showed sexual receptive behavior toward other males
◼ Neonatal androgens “defeminize” males
what was the result of female puppies treated with androgen in utero & neonatally were altered anatomically?
◼ No external vagina
◼ Small phalluses
◼ Urinted in male posture half the time
what happened with adults females when treated with androgen in utero & neonatally were altered anatomically?
◼ Overiectomized & treated w/ female hormones or male hormones
what was the result of dogs on estrogen treatment?
no effect on the dogs showing female sexual behavior
◼ Wouldn’t stand to be mounted
◼ Had been defeminized
what was the result of dogs treated with testosterone?
Experimental dogs would mount other female dogs in heat
what is a freemartin
Abnormal embryogenesis of female repro tract
◼ Unique condition during formation of placenta in the cow
embryonic membranes fuse to form common ________ in freemartins
chorion
because of the shared blood supply in freemartin what happened to the embryos?
◼ Embryos exposed to same hormones
◼ Female exposed to testoterone & antimullerian hormone from male fetus
with freemartin, which genitalia developed first?
testes occurs before ovaries
what is the role of the antimullerian hormone?
Inhibits growth of paramesonephric ducts
mullerian ducts
what happens to the paramesonephric ducts as the female reproductive tract develops?
don’t develop completely
in freemartin, what happened when the ovaries cease to grow?
◼ Don’t develop completely
◼ Don’t produce estrogen
◼ Can produce testosterone
true/false: Higher levels of androgens or hormones will increase libido or receptivity
false
true/false: Hormonal treatment will not cure aberrant sexual behavior
true
what is the purpose of ovarian hormones?
Attraction to & receptivity to male mounting
which ovarian hormone is significant to cats and pigs
estrogen
which ovarian hormones are significant to dogs and sheep?
estrogen and progesterone
what is the purpose of ovariectomies
Abolishes estrus behavior in females
define orchiectomy
Abolishes sexual behavior in males
true/false: The more experienced the male, the longer sexual behavior will persist after castration
true
which pubertal castration is more effective at eliminating sexual behavior, pre or post?
Pre-pubertal castration
why are anatomical factors important for castration?
b/c small penis precludes successful intromission
Neural damage to penis results in:
◼ Mis-orientation in tomcats
◼ Failure to ejaculate in bulls
what is the result of desensitization of the vagina in cats?
inhibits ovulation
what and why is it important for successful intromission and ejaculation of tomcats?
penile spines which induces ovulation
what are animals influenced by in terms of social and sexual experience that is more common than abnormal hormone levels?
influenced by lack of adequate sexual experience
describe lack of socialization
◼ Raised in isolation
◼ Suppresses sexual behavior in males
what is the most obvious effect of lack of socialization to conspecifics is on sexual behavior
critical periods
what was the result of male dogs raised in isolation from other dogs from 3 weeks of age
◼ Normal libido toward estrus bitches
◼ Orientation was wrong
◼ Mount improperly & seldom achieve intromission
◼ Probably an effect of lack of mounting experience
- Large part of puppy play
what happened to boars raised in isolation form three weeks old?
very little sexual behavior
what happened to the all male groups when boars were raised in isolation from three weeks old?
◼ Individuals direct their sexual attention to other
males
◼ Dominant males may continue to mount other males even in presence of estrus females
◼ Some homosexual behavior will cease over time
- Breeding efficiency is affected
what are causes of negative sexual experiences?
◼ During mating -deleterious effects on future sexual behavior ◼ Overt aggression by sexual partner ◼ Rough handling by stock person ◼ Injury sustained during mating
what kind of animals do we see more attractiveness of a potential mate?
higher mammals
what does attractiveness of estrous bitch’s urine depend on?
hormonal state
when females were treated with either estrogen or testosterone, which urine were the males more attracted to?
female’s urine treated with estrogen
what is the purpose of the marking behavior of males
Attempt to mask attractiveness of bitch urine
why may females show individual preference for one male over another?
female’s innate preferences or past experiences
what can make a male’s preference be physiological?
pheromone release
why can males show individual mate preference?
◼ Psychological or idiosynchratic
◼ May be evolutionary basis
◼ Males may prefer females that are similar, but not too similar
-Same gene pool propagated without inbreeding
what are some examples of distractions in terms of external environment?
◼ Too many observers
◼ Slippery footing
how may the presence of another male be an effect of the external environment?
stimulates sexual behavior
what is an example of the time of day being an external environmental factor
Cows show more signs of estrus at night
how can introducing novel stimulus animal enhance sexual behavior
coolidge effect- Restoration of mating behavior in males when original female is replaced by novel female
how can a change in settings enhance sexual behavior?
new environment
how can sexual preparation enhance sexual behavior?
◼ Maximizes output of spermatozoa per ejaculate ◼ Prolong pre-copulatory stage
◼ False mounting
- Mounting without intromission
◼ Restraint
- Prevent from mounting when 2-3 feet from female
idiosynchratic
male’s personal preference to mate with a specific female
