Principles of Animal Nutrition Exam 2

What are the seven Macro-minerals?

Calcium, Phosphorus, magnesium, sodium, chlorine, potassium, and sulfur

What are magnesium’s major functions?

Skeletal development, oxidative phosphorylation, ATP-related enzymes, phosphatases, carboxylation, and peptidases

Where is magnesium mainly absorbed?

The ileum

Does magnesium absorption require vitamin D or a carrier?

No; neither is required according to the slides

What does hyperparathyroidism do to magnesium?

Increases urinary Mg loss and reduces serum Mg

What are signs of magnesium deficiency in growing rats?

Anorexia, poor weight gain, low serum Mg, tetany, and hyperemia of ears/extremities

What are signs of magnesium deficiency in pigs?

Weak/ crooked legs, irritability, twitching, reluctance to stand, tetany, and death

What other problems can magnesium deficiency cause?

Osteoporosis, elevated histamine, and kidney calcification/necrosis

Which mineral deficiency causes hypomagnesemia tetany?

Magnesium deficiency

What are potassium’s functions?

Osmotic and acid-base balance, enzyme activity, nutrient uptake, protein synthesis, and heart/kidney integrity

Where is most sodium located?

About 90% is outside cells

Where is most potassium located?

About 90% is inside the cells

What does Na/K ATPase do?

Uses ATP to maintain sodium and potassium gradients across cell membranes

Approximately how much cellular ATP is used for the Na/K pump?

About 25%, according to the lecture slides

What are sodium’s main functions?

osmotic pressure, acid-base balance, and nerve impulse transmission

What are chlorine’s main functions?

extracellular osmotic pressure, acid-base balance, and gastric HCl formation

Where are sodium, potassium, and Chlorine absorbed?

Mainly in the upper small intestine, by passive and active transport

Are Na, K, and Cl significantly absorbed in the stomach?

No

What are signs of potassium deficiency?

Heart ECG changes, kidney lesions, weakness, poor growth, pica, unsteady gait, diarrhea, and possibly death

Which mineral deficiency may cause secondary potassium deficiency?

Magnesium deficiency

What are signs of sodium deficiency in growing animals?

Poor growth and feed efficiency; reduced plasma volume and hemoconcentration

What are signs of sodium deficiency in growing animals?

Reduced milk production and weight loss; animals may drink urine

What are signs of chlorine deficiency?

Poor growth, kidney lesions, low tissue/urinary Cl, and noise-triggered nervous reactions in chicks

What is the common function of Na, K, and Cl?

Maintaining fluid/osmotic and acid-base balance

Which sulfur-containing amino acid are listed?

Methionine, cystine, and cysteine

Which sulfur-containing vitamins are listed?

Biotin and thiamine

What are sulfur’s functions?

Protein, connective-tissue, energy, and acid-base metabolism

What are sulfur’s functions?

Protein, connective-tissue, energy, and acid-base metabolism

Where is sulfate absorbed?

Upper small intestine by actie transport

What are sulfur deficiency signs?

Functional/tissue lesions, increased sulfur-AA needs, and reduced wool growth and weight gain

What is cobalt’s primary nutritional function?

It is component of vitamin B12

What happens with cobalt deficiency in ruminants?

Anorexia, poor growth, emaciation, normocytic normochromic anemia, and possibly death

What organ changes can cobalt deficiency cause?

Liver degeneration and splenic hemosiderosis

What cobalt-deficient dietary range is given for ruminants?

Below about 0.07-0.11 ppm on a dry-matter basis.

What is iodine’s main function?

Constituent of thyroid hormone thyroxine (T4)

What does iodine deficiency do to basal metabolic rate?

Decreases it, with poor growth and reduced gonadal activity

What is the common sign of iodine deficiency?

Goiter, or enlarged thyroid gland

What is iodine deficiency called in young animals?

Cretinism

What is iodine deficiency called in adults?

Myxedema

What skin and hair signs suggest iodine deficiency?

Dry skin and brittle hair or hairlessness

What reproductive signs suggest iodine deficiency?

Abortions, stillbirths, fetal resorption, irregular estrus, and poor male libido/semen

What are goitrogens?

Dietary substances that interfere with thyroid function and may promote goiter

What goitrogen occurs in cassava?

Thiocyanate

What goitrogens occur in cabbage, rape, and mustard?

Glucosinolates

What goitrogen is listed in soybeans?

Glucopeptide

What goitrogen-related compounds are listed in peanuts?

Metabolites of anthocyanin

Which enzymes contain or require zinc?

Carbonic anhydrase, carboxypeptidases, dehydrogenases, alkaline phosphatase, ribonuclease, DNA polymerase

What are zinc’s other functions?

Immune function, protein synthesis, insulin function, and carbohydrate metabolism

What is a classic sign of zinc deficiency in pigs?

Parakeratosis (thickened, hyperkeratinized skin)

What are general signs suggest zinc deficiency in pigs?

Poor growth, anorexia, low plasma Zn, and reduced alkaline phosphatase activity

What are zinc deficiency signs in rats?

Cracked/scarred paws, course hair, and alopecia

What are zinc deficiency signs in sheep?

abnormal wool and horn development

What are zinc deficiency signs in poultry?

Poor feathering and dermatitis

How does zinc deficiency affect bone?

Poor cartilage proliferation, low bone alkaline phosphatase, and reduced bone density

How else does zinc deficiency affect animals?

Poor reproduction, delayed would healing, and impaired glucose tolerance

What are iron’s major functions?

Hemoglobin, myoglobin, metalloenzymes, and heme enzymes for oxygen-related metabolism

Which heme enzymes are listed for iron?

Catalases, peroxidases, and cytochromes

What protein carries iron in blood?

Transferrin

What protein stores iron?

Ferritin, especially in liver, spleen, and bone marrow

What is hemosiderin?

A brown, granular iron-containing pigment

What anemia is characteristic of iron deficiency?

Microcytic, hypochromic anemia

What are iron deficiency signs in piglets?

Pallor, labored breathing, rough coat, poor appetite/growth, and susceptible to disease

What muscle appearance can iron deficiency cause in suckling calves/lambs?

Light-colored muscle

What are copper’s main functions?

Iron metabolism, red blood cells, collagen/elastin, pigmentation, bone, and nervous system integrity

What does ceruloplasmin do?

Regulates iron release from cells with mobilizable iron stores

What does lysyl oxidase support?

Normal elastin formation in the aorta/cardiovascular system

What does cytochrome oxidase support?

Normal myelination of brain and spinal cord cells

What is swayback?

Enzootic neonatal ataxia in lambs associated with copper deficiency

What are neurological sings of copper deficiency?

Incoordination and ataxia, especially in lambs

Why can copper deficiency cause anemia?

Reduced RBC lifespan and impaired iron absorption/utilization

What coats signs suggest copper deficiency?

Steely wool, alopecia, poor fiber growth, and loss of pigmentation (achromotrichia)

What skeletal and cardiovascular signs can copper deficiency cause?

Bone abnormalities, vascular lesions, and hemorrhage

What is manganese needed for in bone?

Chondroitin sulfate and normal skeletal development

What enzymes/metabolism involve manganese?

Glycosyl transferases, carbohydrate metabolism, and liver lipid synthesis

What are skeletal signs of manganese deficiency?

Lameness, bowed/short legs, enlarged joints, and poor skeletal development

What is perosis?

Slipped tendon in birds; a classic manganese deficiency sign

What is chondrodystrophy in birds?

Short, thick legs/wings and parrot beak, associated with manganese deficiency

What eggshell problems follow manganese deficiency?

Reduced eggshell thickness and strength

What is star-grazing posture associated with?

Manganese deficiency in chicks

What reproductive problems can manganese deficiency cause?

Poor estrus/conception, small litters, low hatchability, low libido, and failed spermatogenesis

What enzyme contains selenium?

Glutathione peroxidase

What does glutathione peroxidase do?

Breaks down peroxides and helps preserve cell membrane integrity

What pancreatic functions depend on selenium?

Normal pancreas and pancreatic lipase, supporting fat/tocopherol absorption

What is nutritional muscular dystrophy?

white muscle disease, associated with selenium and/or vitamin E deficiency

Which animals can develop selenium-related white muscle disease?

Lambs, poultry, pigs, and calves

What poultry condition is linked to selenium deficiency?

Exudative diathesis

What liver condition is linked to selenium deficiency?

Liver necrosis (hepatosis dietetica) in rate and pigs

What are the five mineral toxicants covered?

Lead, cadmium, mercury, fluorine, and molybdenum

How can lead enter the body?

GI tract, lungs, and skin

What blood abnormality can lead toxicity cause?

Microcytic, hypochromic anemia

What lab findings suggest lead poisoning?

Elevated blood Pb and urinary aminolevulinic acid

What are lead’s kidney and GI effects?

Kidney pathology; stomach/small-intestine necrosis, bleeding, and ulcers

What are lead’s nervous-system effects?

Petechial hemorrhage, loss of myelin, and cerebrocortical softening

What are lead’s skeletal effects?

Osteoporosis, enlarged joints, and reduced bone matrix formation

What dietary factors can reduce lead toxicity?

Higher Ca, P, Fe, Mg, Zn, vitamin E, ad marginal protein (per slides)

What dietary factors aggravate lead toxicity?

Higher Hg, Cd, Mo, Se, F, and vitamin D (per slides)

What organs are particularly damaged by cadmium?

Testes and kidneys

What other signs can cadmium toxicity cause?

Anemia and depressed growth

What dietary minerals partly reduce cadmium toxicity?

Iron and Calcium

Hoe does mercury disrupt enzymes?

Inhibits enzymes with sulfhydryl (-SH) groups