Water Quality Flashcards
How does temperature affect water consumption?
extremely cold or hot is not palatable
cold water will also lower feed consumption
What other factors change the palatability of water?
decrease:
- extreme pH, salinity, odour, taste
- sulphate for most species
increase:
- swine and high sulphate water
What factors can water be test for?
microbiology hardness salinity ions agents
What is involved in the microbiology testing of water?
bacterial counts
specifically e.coli counts
What species is e.coli often isolated from? is this a problem?
cattle
has little impact (human problem)
What elements contribute to water hardness?
Ca, Mg, Calcium carbonate
the more mg/L the harder the water
Is water hardness used to assess toxicity?
nope
What is salinity and does it assess water quality?
total dissolved solids after carbonates are converted to oxides and halogens are converted to chloride
“measure of inorganic substances”
- typically Ca, Mg, Na, HCO3, Cl, SO4 ions are involved
sometimes conductivity is measured
- indirectly reflecting ion concentrations
What water has the highest salinity vs lowest?
fresh < brackish < salt < brine
Which species are the most susceptible to salinity?
poultry followed by dairy cattle
most species can tolerate 4-5,000 mg/L
What does high TDS cause in animals?
diarrhea, poor growth
reduced productivity
unfit during periods of heat and stress
What are the limitations with detecting hardness or salinity?
doesn’t get to underlying problem
What are some examples of a more in depth water analysis ?
metals, anions, nitrates, pesticides, ammonia
What indicates hydrogen sulfide decomposition?
rotten egg smell
What indicates high iron in the water?
bitter taste
What indicates insecticide toxicity in water?
dead invertebrates
What are some things to note about the animal when dealing with elevated sulphate in the water? acutely and chronically?
diarrhea
extended exposure will interact with metals (Se, Cu) and produce deficiencies and clinical disease
moderate exposure adaptive response likely
What can cause insecticide/herbicide contamination of water?
run off, spray drift, rain fall, spills, poor disposal, direct application
Why is insecticide/herbicide analysis not routine? what is the typical approach?
expensive and difficult
clinical exam and biochemical assessment followed by tissue sample to assess single agent
good clinical exam, history, post mortem is better than broad analytical eval (sometimes not possible if can see cattle)
What is the unit conversion for ppm -> % /mg?
1ppm = 0.0001% 1% = 10,000ppm 1ppm = 1mg/kg = 1ug/g
will be a question on what is the toxic amount, given dose and concentration
