Water

Question 1

what does water contribute to?

Answer 1

• regulatory
• structural

essential for life & most abundant & cheapest

Question 2

what are the functions of water?

Answer 2

• nutrient/waste transport
• metabolic/chemical reactions
• aids digestion/absorption
• regulates body temperature
• regulate ionic concentrations
• body structural component
• lubricates/cushions
• involved in sight & sound
• maintain blood volume & osmotic pressure
• reproduction

Question 3

what are the sources of water?

Answer 3

• drinking:
  
  • tap, stream, direct consumption
• food/feed:
  
  • early morning dew on the grass of grazing ruminants
    range <10% - >90%
• metabolic water (5-10% total)
  
  • liberated during catabolism of body tissue
  • importance depends on species, diet, habitat, and
    ability to conserve water

*kangaroo rat never needs to drink water
- More water obtained via metabolic water than lost
via respiration, urination, fecal losses

Question 4

nutrient composition of adult bovine & plant?

Answer 4

adult bovine: 54%

green plant: 70%

Question 5

factors affecting water intake

Answer 5

requirements not fixed:
- depends on the availability and temperature of the
water
digestive system:
- ruminants > non-ruminants
within species:
- intake varies on production purpose/function
- size age of the animal
- pregnancy, lactation, growth
the type of diet: (IMPORTANT)
- level of intake depends on the type of diet
- green forage vs silage vs hay
environmental temperature & humidity
- ex: mature cattle heat stress
- not stressed 5-6% BW consumption
- stressed >12% BW consumption
physiological function
- lactation, work (sweating)
disease condition
- fever, diarrhea
water quality & accessibility

Question 6

water requirements for humans

Answer 6

humans-adults:
- 1 milliliter
- 2000 ml per 2000 kilocalories
- environmental conditions affecting water intake:
- air conditioning & trade winds

humans-children:
- 1.5 militer

Question 7

water requirements for animals

Answer 7

dairy cattle 10-16 (gallon/day/head)
beef cattle 8-14
horses 8-14
swine 2-4
sheep & goats 1-3
chickens (hens) 8-10
turkeys 10-15

Question 8

dietary factors affecting water intake

Answer 8

feed water: decrease
DM intake: increase
protein content: increase
salt content: increase
indigestible fiber: increase

Question 9

what are palatability and toxic factors affecting water quality?

Answer 9

palatability factors:
- total dissolved solids
- alkalinity
- sulfur
- stagnant water

toxic factors:
- nitrates
- trace minerals (saline water)
- bacteria
- pesticides & herbicides

Question 10

where does water enter our body? where does it go to?

Answer 10

intracellular fluids

extracellular fluids
- interstitial fluid
- plasma

Question 11

where does water loss go?

Answer 11

• urine
  
  • under control of hypothalamus & adrenals
• feces
  
  • intestines - varies on species, type of diet, & health &
    status
• lungs & skin (vaporization) - temp. & activity
• sweat glands - skin

Question 12

water deficiancy

Answer 12

• lack of water = decrease in appetite & productivity
• restriction causes dehydration, loss of water and
  weight loss, increase the loss of electrolytes
• dehydration -> scours ( diarrhea of newborn animals)

Question 13

when water enters/leaves the body, what do the cells look like?

Answer 13

animal cells:
- water enters, the cells swell
- water leaves, the cells shrink

Question 14

importance of osmoregulation?

Answer 14

• maintains correct water balance in the body
• excessive water gain/loss can upset the proper
  functioning of the cells in the organs
• metabolic reactions are affected = organisms may die

Question 15

kidney functions (removal of excess salt)

Answer 15

after eating salty meal -> salt enters blood, concentration of salt increases blood -> man feels thirsty -> drink water -> volume of urine increases -> concentration of urine is higher