1. Reproductive and parental behavior
A.J. Zanella
ANS 305

2. Objective
To discuss reproductive behavior in domestic mammals

3. Pre-copulatory and copulatory behavior
Courtship
Motivational aspects
Enhance sperm production
Enhance fertilization
Increase litter size (pigs)
Copulatory responses
Consummatory responses
Most of the current information is on males
Exception dogs and cats

4. Variability in sexual behavior
Males
Courtship is highly variable
Licking & sniffing the female genitalia
Nudging
Vocalizations
Copulation is less variable than courtship

5. Variability in sexual behavior
Females
Courtship (proceptive behavior)
Mounting behavior (cows)
Urination (mares & ewes)
Seeking out & selecting males
Copulatory behavior
Receptive behavior
Passive responses (?)
Exceptions: cats & dogs

6. Domestic mammals (females)
Cyclic nature
Display no interest in males and will not be receptive outside the estrous period
Olfactory, auditory and visual stimuli produced by females have “attractive” qualities to males
Females display preferences for sexual partners
Sows; ewes; bitches & female cats

7. Mate choice and timing of mating

8. The evolution of seasonal breeding
Domestic species evolved in temperate climates
Reduce risk of predation
Avoid delivery at the times when resource are limited
Domestication has altered seasonal reproductive behavior in several species

9. Species Estrous cycle Length Duration
Dog Monoestrous cycle/season (2x) days
Cat Seasonally weeks days
polyestrous days
Horse Seasonally weeks days
polyestrous
Cattle Polyestrous weeks hours
Sheep Seasonally days hours
Goat Seasonally weeks hours
Swine Polyestrous weeks 2-3 days

10. Behavioral signs of estrus
Sensory and motor activity
Increase in general activity
Ovulation in women (Morris & Udry, 1970)
Increase in sensory acuity
Neuronal “re-organization”
Visual
Olfactory
Spatial memory

11. Behavior of estrus females towards males
Proceptive behavior
Females will seek males
Standing behavior
Vocalizations
Urination
Mares, sheep and goats

12. Female responses during copulation
Limited data ?
Copulation causes an increase in uterine motility
Uterine motility follows nuzzling and mounting by a bull
Female cats, 5 to 10 seconds post-intromission, becomes very aroused (eyes dilate, they may turn and hit the male)

13. Behavior of estrus females towards other females
Agonistic interactions
cows; pigs; mares
Increase in vocalizations
Attempts to mount other animals
cows; bitches; sows
Standing while mounted by other animals
Cows (56 times over a 15 hours period)
PRESENCE OF MALES MAY ELICIT MORE PRONOUNCED BEHAVIORAL RESPONSES

14. Sexual behavior of males
Pre-copulatory behavior is highly variable
Beef bulls have a more elaborated courtship display than dairy bulls
Male broiler breeders (domestic fowl) are more aggressive towards females than commercial laying strain males (Millman et a,, 1999)

15. Sexual behavior of males
Investigate the genitalia of the female
Flehmen behavior may follow
Play behavior (dogs)
Mounting
Attempt copulatory intromission by pelvic thrusting

16. Stallion

17. Bull

18. Boar

19. Ram

20. Goat

21. Olfactory stimuli Pheromones Vaginal secretions Urine Preputial gland
Substance produced by one animal which conveys information to other individuals by olfactory means
Vaginal secretions
Urine
Preputial gland
Salivary glands

22. Pheromones Hamsters Dogs Pigs Dimethyl disulfide in vaginal secretions
Methyl-p-hydrobenzoate in urine of bitches
Pigs
Androgenic steroids is saliva of boars

23. Detection of pheromones
Olfactory system
Volatile substances
Vomeronasal organ
Flehmen behavior: head elevation and curling of the upper lip.
Non-volatile substances
Primarily performed by males
Females may show the behavior towards newborn animals or amniotic fluid.

24. Flehmen behavior
Fluid is drawn from the oral cavity through the nasopalatine duct and to the posterior part of the vomeronasal organ.

25. Inclusive reproductive fitness
Males may help close relatives (horses)
Females may support sisters when they are not able to breed
Wolf packs:
only the dominant females have pups
their female relatives help to look after the young

26. Sexual suppression Females Males Honey bees Some primates
Naked mole rats
Males
Stallions

27. Monogamy
Domestic dogs are the only domestic species that retain “some” indicative of monogamous behavior