Macro Minerals - Exam 3 Flashcards
Calcium absorption
Dependent of calcium status, age, chelating agents
Biological role of Ca
Bones
Milk
Calcium deficiency/imbalance
Can be caused by P or Vit D deficiency
Osteoporosis
Cage layer fatigue
Milk fever
Calcium Toxicosis
Very rare
Osteopetrosis
Urinary calculi
What age groups need extra calcium?
Adolescent and geriatric
Phosphorous absorption
Doudenum
Dependent on source (phytic acid)
Ca:P
Phosphorous excretion
Urine
Biological Role of P
Bone
Every aspect of tissue metabolism
P deficiency & imbalance
Deficiency basically unheard of
Imbalance more common in ruminants
Causes weak bones, reduced production, pica
Levels measured in blood plasma
P toxicosis
Urinary calculi
High P and low Ca causes PTG, resorbs bones and excretes P, leads to bone loss
How to prevent P toxicity
Don’t feed excess commercial grain
add urine acidifiers
feed whole grains
What feeds are high/low in P and Ca
Grains are high in P, low in Ca
Forages are low in P, high in Ca
Magnesium absorption
ileum of monogastrics
reticulorumen of ruminants
Dependent on carbohydrate source (more carbs > more absorption)
More organic acids, less Mg absorption
Ca, P, K adversely affected
Mg excretion
Urine and feces
Mg biological role
Bone developments
Activator for enzymes
Cellular respiration
Important for decarboxylation of alpha-keto acids
Mg deficiencies & imbalances
True deficiencies uncommon
Physiological deficiencies known as grass tetany
More common in spring when cold snaps reduce availability of Mg in grass
Causes neuromuscular symptoms including foaming mouth
Treatment with IV Mg
Urinary and RBC Mg tested (or just treat)
Mg toxicosis
Unlikely except accidental poisoning
Causes lethargy, diarrhea, death
Where is the majority of Mg in the body
50-60%
30% associated with bone P
Where is remaining Mg found
Soft tissues- liver and skeletal muscles
Sodium absorption
Active through intestine
Passive through stomach
Na excretion
Inverse relationship between K and Na
Urine
Biological role of Na
Osmotic pressure regulation
Deficiency of NA
Causes decline in urine excretions
May drink urine
Na Toxicosis
Can be caused by high salt in water
Increased water intake, edema, death
Chickens very sensitive to salt, no more than 2% salt
What is Na always found with
Chloride
Location of K, Na, Cl
K: intracellular
Na: extracellular
Cl: extracellular
Is lots of salt needed in the diet?
No, extensively recycled through endogenous secretions
Large salt intake makes small impact on absorption
Chloride absorption
Passive through intestine
Active through stomach
(Opposite sodium)
Cl excretion
Used to balance sodium excretion by kidney
Biological role of Cl
Component of HCl, stomach acid
Deficiency of Cl
Nonspecific symptoms (Pica, lethargy reduced production)
Cl toxicosis
May affect systemic pH
Potassium Absorption
(Same as Na)
active through intestine
passive through stomach
K excretion
Inverse to sodium to maintain balance
Biological role of K
Maintain nervous impulse conduction in muscles and heart (works with sodium)
K deficiency
Abnormal heart rhythms
K toxicosis
Can cause grass tetany
Sulfur absorption
Organic sources (AA): small intestine
Inorganic (Sulfate): very low absorption
S excretion
Urine and feces
S biological role
Disulfide bonds
AAs: Methionine and Cysteine
Two bonded cysteine: cystine
S Deficiency
Affects microbial population
S toxicosis
Sulfur turned into hydrogen sulfide by bugs
No specific symptoms
What is the relationship between Sulfur and Selenium
Selenium can replace the sulfur in AAs, less toxic form
Tetrathiomolybdate
Molybdenum bonded to 4 sulfurs
Can bond Copper
Excess Mo > Cu deficiency
Less Mo > Cu toxicity
