Cross Species - Chemistry Energy & Metabolism Flashcards
what are some non-pathological factors that can influence energy/protein metabolism results on a chemistry panel?
sample handling can cause hemolysis or failure to separate serum from red cells, interference from sample lipemia/icterus/in vivo hemolysis, & analyzer erros from limitations of in-clinic analyzers (failure to accurately measure significantly increased values)
what medications are know to cause pseudohypochloremia & ALP increases in dogs?
hypochloridemia - potassium bromide, increased ALP - steroids
what is the primary cellular energy source?
glucose
what is glucose derived from?
dietary carb metabolism, hepatic gluconeogenesis, & glycogenolysis
what controls glucose levels? changes in it do what?
insulin - pathologic changes will affect BG
what is the stress response of hyperglycemia? what animals is it seen in?
stress - transient increase from release of epinephrine/cortisol that is most pronounced in cats - also a negative prognostic indicator in cattle/horses with disease
why do we see hyperglycemia in end stage equine metabolic syndrome?
chronic insulin resistance causes poor tissue response to insulin, so you will see hyperglycemia despite hyperinsulinemia
what are counter-regulatory hormones that can cause hyperglycemia?
growth hormone in feline acromegaly, pregnancy (also growth hormone), steroids from stress, cushing’s, & PPID
what causes spurious hypoglycemia?
failure to separate serum & cells in a timely fashion causes red cell glucose consumption
what are the top causes of hypoglycemia?
insulinoma, sepsis, addison’s, liver dysfunction/shunt, starvation in neonatal puppies, canine xylitol toxicosis, exertional hypoglycemia in hunting dogs/endurance horses
what are the renal threshold values for glucose in dogs, cats, horses, & cows?
dogs: 180-200, cats: 280-290, horses: 160-180, & cattle: 100-140
is glucosuria diagnostic for diabetes mellitus?
no - only indicates that the renal threshold has been exceeded for any reason
how is fructosamine used to diagnose diabetes in small animals?
evaluates the BG over a longer period of time (2-3 weeks) if increased, prolonged hyperglycemia consistent with diabetes mellitus
what is the metabolism & excretion of cholesterol?
part of lipoproteins in blood that is mainly excreted in bile
what are the top metabolic causes of hypercholesterolemia? what are some others?
diabetes mellitus, cushing’s, & pancreatitis - others include canine hypothyroidism, & cholestasis/extrahepatic biliary obstruction in dogs/cats
what are the two main classes of triglycerides measured in serum?
chylomicrons & low-density lipoproteins
T/F: hypertriglyceridemia can cause visible serum lipemia
TRUE
what are the top causes of hypertriglyceridemia in dogs & cats?
post-prandial in dogs/cats, if fasting dogs/cats, diabetes/cushing’s/pancreatitis
what are the top causes of hypertriglyceridemia in horses?
PPID, EMS, excessive energy balance (hyperlipidemia syndrome) in any horse off of feed but especially in donkeys, mini horses, late term pregnancy, & obese horses
what is the purpose of measuring non-esterified fatty acids in dairy cattle?
to assess excessive negative energy balance in the herd rather than individuals
when are NEFAs measured in dairy cattle?
prepartum: 2-14 days before calving & postpartum: 3-14 days in milk
what does an increase in NEFA in a dairy cow suggest?
the need to increase dietary energy density
what is BHB? where do they come from in cows? what other ketones are included but not measurable?
beta-hydroxybutyrate, in ruminants from NEFA & VFA from rumen metabolism - other ketones include acetone & acetoacetate
what is the main cause of elevated ketones in dogs/cats?
DKA
what is the main cause of elevated BHB in dairy cows?
bovine ketosis post-calving
what are some causes of increased BHB?
negative energy balance stimulates lipolysis & excessive absorption of butyrate due to feeding spoiled silage
total protein is normally divided 50/50 between what values?
albumin & globulin
what is the normal albumin globulin ratio?
1 to 1
what is the production & purpose of albumin?
synthesized by the liver, significant contributor to plasma oncotic pressure, & carrier protein
what causes increased albumin?
dehydration
what are the top causes of hypoalbuminemia?
iatrogenic from overhydration, decreased production from liver dysfunction or acute phase inflammatory response
in PLN, what protein is lost?
albumin
in PLE, what proteins are lost?
albumin & globulin
what are 2 ways in which albumin can be lost in the body?
hemorrhage & third spacing (loss in body cavity effusion)
what is included in globulins?
all non-albumin proteins
electrophoresis divides globulins into what?
alpha (acute phase proteins), beta (acute phase proteins), & gamma (immunoglobulins)
how are globulins calculated if not measured?
total proteins - albumin
what are the top causes of hyperglobulinemia?
inflammatory disease, active immune response (polyclonal gammopathy, FIP), in horses, gi parasitism & liver disease, & neoplasia (monoclonal gammopathy - multiple myeloma or lymphoma)
what is the top cause of hypoglobulinemia in foals?
congenital/inherited immunodeficiency in foals
what is fibrinogen? how long does it take to see changes in the numbers of it?
acute phase protein made by the liver that increases with inflammation - takes 24-48 hours to see an increase or decrease
what animals do we routinely measure fibrinogen on?
horses & ruminants as an adjunct to a CBC
what are the top causes of hypocholesterolemia?
hepatic dysfunction/shunt, in dogs, malabsorption/maldigestion (PLE), & in dairy cattle, lipidosis (increased NEFA:cholesterol ratio)
