Nitrates Flashcards
Nitrate sources are…
Plants and commerical fertilizers or stored feces that accumulate in the vegetative tissues (not in the fruits and grains)
Nitrates are high when farmers cut when its _______ and highest conc. of nitrates are where in the plant?
Wet and overcast; are closer to the ground in the distal parts of the stem.
When are nitrate levels the highest?
Just prior to flowering and drop off rapidly after pollination and when grain/fruits “set”
When are the high risk periods for nitrate/nitrite poisonings?
Heavy fertilization, runoff unto water, drought, cloudy days (or at night- lower level of photosynth.), desiccation (wilting) of plant makes it more conc.
Nitrates and nitrite are ___ soluble and they are easily leached into ___ ____
water; ground water
____ is more toxic than _____
Nitrite; Nitrate
Ensiling contributes to ?
Silo burps– anaerobic fermentation resulting in some of the nitrate converting to oxides of nitrogen. Can be deadly at very high doses
How much exposure to nitrates is considered safe?
Less than 5000ppm
______% of nitrates in cattle feed is an issue if fed for more than ___ days
0.3% (3000ppm) for 3 days
What animals are most susceptible to nitrate poisoning? What does it cause?
Ruminants; causes oxidation of Hgb to methemoglobin (ferrous iron) which results in tissue anoxia and death
Nitrates require ___ days to return to normal levels. Low and high temps with _____ levels.
14 days; increase levels
Nitrate poisoning etiology:
Nitrogen fertilizers increase the levels, soil deficient in P, K, S, MO, acidic soil, feeding hay that was rained on
Nitrate toxicity (CHRONIC):
Chronic exposure: poor growth rate, abortions, infertility, Vit A def, goiters, high morbidity to disease
Nitrate poisoning clinical signs per species:
Cattle are most affected, then goats/sheep, and lastly horses and swine
Clinical signs of nitrate poisoning:
Cyanosis, brown cast to mmm, Dark, chocolate colored blood, tachy, muscle tremors, GI signs, abortions
