Nutritional/Toxicological Dx Flashcards
what is something to always keep in mind when interpreting analytics?
variable
deficient, marginal, normal, high normal, toxic
status range varies and what the animal presents with
What 6 factors influence interpretation of results?
season, age, species/breed, disease/metabolic/physiologic, nutrient, tissues
What is an example of a seasonal factor influence with Cu?
livestock consume vitamin and mineral rich feed in the summer.
nutrients are slowly released during winter when high quality feed is poor
- will see rise in Cu during summer
- a cow with low Cu in fall is deficient and will cause problems by late winter.
same pattern occurs with Vit A and E
What is an example of an age factor influence? VitA/E, Se, Cu, Mn
Vit A/E levels in a fetus or calf may be deficient in an adult
Manganese levels are 2x lower in the fetus/newborn
Se levels are 2x higher in fetus
Cu levels are extremely high in newborn elk livers (other species it is consistant) where the female after birthing several calves is Cu deficient due to sequestration in the fetus
Foals have low Cu concentrations in the blood at birth, by 3 weeks it approaches normal
What is an example of a species difference influencing factor?
suppressed brain cholinesterase activity, indicating acute organophosphate or carbamate toxicity is extremely variable between species
What is noted with species and breed variability with Cu?
difference between sheep and cattle
pigs, horses, avian are different
llama and alpacas do not develop the classical hemolytic crisis associated with Cu poisoning
different breeds of goats
bedlington terries store Cu and develop toxicity quicker
What can be the bodies response to infectious diseases (bacteria, viral, protozoal, parasitic) that influence analysis? what elements is this seen with?
sequester elements to “starve” infectious agents
= low blood, high in liver
normal but out of balance
seen with Zinc, iron as well as Cu and Se
what is a disease in dogs associated with abnormal Cu accumulation? why does high Magnesium occur in addition?
chronic hepatitis in dogs
hemolysis shows high Mg from hemolysis process
What are some physiological states that alter analysis?
starvation and dehydration will suppress brain cholinesterase can be confused with organophosphate and carbamate exposure
Stress = zinc is very low
What is the classical interaction between two nutritional elements influencing analysis? what elements have similar interactions?
molybdenum inhibits the absorption and metoblism of Cu and enhances excretion
normal Cu intake can still have deficiencies
multi-element analysis crucial
Na-Li, zinc-cadmium, Se-Arsenic, Se-Mercury, lead-iron, Cu-zinc etc
What nutritional interaction occurs with Se/Vit E?
may partially replace each other functionally but need both
deficiency of one = disease
marginal def of both = disease
low vit E enhances potential for toxicity for agents that cause oxidative damage (e.g. iron) even though its normal
also extensive iron will deplete Vit E stores..
example
acetominophen poisoning = vit E treatment
iron toxicity = chelator or Vit E
What are two mechanisms that can trap substances in tissue?
ion trapping or protein binding
What is more reliable than blood concentrations?
liver concentrations
What are examples of tissues that can change the analysis of a substance?
Se higher in red blood cell (better than looking at serum or plasma)
- except following injection (time to get into erythrocyte)
cholinesterase activity associated with rbc in most species where humans and avian have more in plasma (caution when giving samples to human hospital)
What can be used to help interpret urine analysis for indicating toxicity or exposure?
urine volume and kidney damage changes concentration
24 urine collection reduced variability
concentration per creatinine levels
