Lecture 14: Melatonin, Serotonin, Sleep, and Species-specific Biological Rhythms

Domestic dogs spend > than or equal to ___ hours/day sleeping/resting- mostly in ___

-12 -scotophase

Lying incudes....

-45 mins of REM -3.5 hours of SWS

Kennel dog time & sleep

-active- 33% -resting- 34% -light SWS- 12% -deep SWS- 15% -REM- 6%

Like dogs, cats have periods of ___ interspersed with periods of ___.

-activity -rest

Moving pigs to a new group disrupts ___ ___ of behavior and physiology due to ___ ___

-circadian rhythms -stress response (fight or flight)

Cats are ___- meaning that they're most active at...

-crepuscular -dusk & dawn

Melatonin synthesis is promoted by ___ and inhibited by ___

-dark -light

Cattle are ___ and sleep about ___ hours/day

-diurnal -4

Horses are predominantly ___ so most grazing activity is during ___

-diurnal -photophase

EEG (electroencephalography): as nerves fire in the brain, they generate ___ ___ that are propagated through neighboring cells, which produces a ___ of electrical activity

-electrical impulses -wave

REM: "sleep of the body" is characterized by...

-high brain activity (high frequency if EEG) and vidid dreams & little to no body movement -dreaming in humans; dreaming in pets? -animal difficult to arouse

For pigs, eating (rooting) ___ to ___% of time budget when housed outdoors

-increases -30%

Serotonin synthesis is promoted by ___ & inhibited by ___

-light -dark

Cattle are entrained to ___ & ___

-light -feeding

SWS: "sleep of the mind" is characterized by...

-low brain activity (low frequency in EEG) -animal fairly easy to arouse

Stabled horse time budget

-moving 2% -drinking 2% -lying 6% -feeding 44% -standing 46%

Serotonin is a ___ produced by the ___

-neurotranmitter -CNS

Melatonin is a hormone produced by the ___ ___ in response to a signal by the ___

-pineal gland -SCN

Przewalski's horse time budget

-resting 11% -moving 12% -standing 22% -grazing 55%

Dogs have ___ periods of activity interspersed with ___.

-short -rest

Primary cow behaviors are...

1. feeding (2-8 hours/day) 2. lying (10-14) 3. standing (4-8) 4. ruminating (12)

What 2 things are used to classify the type of wave?

1. frequency 2. amplitude (voltage)

The main 2 functions of serotonin

1. important in regulating circadian rhythms of body temperature, sleep, and appetite 2. regulates anger, aggression, and mood

Pet cats entrain to...(3)

1. light 2. feeding time 3. owner behavior

The 2 most important hormones in regulating behavior are...

1. melatonin 2. serotonin

Circadian rhythm hormones incude...(4)

1. melatonin 2. serotonin 3. cortisol/corticosterone 4. IGF-1

Importance of sleep (3)

1. occupies 1/6-1/5 of animal's time budget 2. extended sleep deprivation is fatal 3. rebound sleep is observed after short term sleep deprivation

3 main functions of sleep

1. replenish neurotransmitters 2. conserve energy 3. consolidate memories/learning

Types of sleep (2)

1. slow wave sleep (SWS) 2. rapid eye movement (REM)

The 2 main functions of melatonin

1. to signal photoperiod to body tissues (along with cortisol/corticosterone which coordinates body tissues function to approbate time of the day) 2. stimulates immune system

Cats sleep about ___ hours/day and "rest" most of their day

10

Pigs rest ___ hours/day; more than any other domestic species

19

Horses sleep about ___ hours/day

3

Pigs sleep ___ hours/day

8 (6 slow wave & 2 REM)

What major cat behavior (comfort behavior) accounts for 30% of cat's time budget?

????

Horses must lay down (sternal or lateral) for ___ sleep though.

REM

Domestic pigs show ___ activity pattern

diurnal

Feral pigs are often nocturnal (to avoid predators?) whereas farmed pigs are...

diurnal

Beef cattle in summer are both ___ & ___

diurnal & crepuscular

Chickens exhibit ___ & ___ behaviors as well

diurnal & crepuscular

EEG (electroencephalography): ___ are placed on scalp that measure waves of electrical activity in the brain

electrodes

Main activity of the mare is ___

feeding (grazing)- 12 to 19 hours/day

Cattle spend most of the photophase ___

foraging

Providing feed reduces the time spent....

foraging/grazing

Horses spend more time ___ when grass is lower in yield/quality

grazing

Rumination occurs mostly when ___

lying

___ prevents animals from displaying natural behavioral patterns

overcrowding

Pet dog behavior patterns are strongly influenced by ___

owners- active when owner's home

Dogs tend to be the most active in...

photophase

Cattle spend much of the scotophase ___

ruminating

Cattle display circadian rhythms in ___

rumination

Horses have unique ability to have ___ ___ ___ when standing (cows can't do this)

slow wave sleep

Feeding mostly occurs when ___

standing

REM EEG looks just like...

the EEG of an awake person!

Indoor housing reduces time spent...

waling & grazing/foraging