Feeding Related Problems in Horses Exam 2

Question 1

What two things need to be considered when selecting feeds for horses?

Answer 1

-nutritional value
-feed quality

Question 2

How to determine nutritional value?

Answer 2

-nutrient requirements vary
-choose feeds that meet needs closely
-avoid deficiencies

Question 3

How to determine feed quality?

Answer 3

choose feeds that are free from
-toxins
-microbial contaminants
-insect contaminants
-injurious materials

Question 4

What can white mold cause?

Answer 4

respiratory inflammation

Question 5

What can tall fescue become infected with?

Answer 5

endophytes

Question 6

Where is tall fescue common?

Answer 6

in the Southeastern US

Question 7

Endophyte

Answer 7

a fungus that lives inside the plant
-conveys some hardiness

Question 8

What do endophytes produce?

Answer 8

ergot alkaloids (including ergovaline)

Question 9

What affect does ergot alkaloids have on animals?

Answer 9

-a negative affect
-vasoconstriction (leads to more heat stress)
-hormonal disregulation

Question 10

What horses are most negatively affected by endophyte infected tall fescue?

Answer 10

late term pregnant mares

Question 11

What are the signs/problems caused by infected mares?

Answer 11

-delayed/absent mammary development (no milk)
-prolonged gestation
-large weak foals
-placental thickening (“red bag” at foaling)
-dystocia

Question 12

What occurs during normal foaling?

Answer 12

the pale white/gray amnion comes out first and the chorionic surface of the placenta is still in the uterus

Question 13

What occurs during red bag foaling?

Answer 13

the placenta has prematurely separated and the chorionic surface appears first

Question 14

How to prevent endophyte infections

Answer 14

limit exposure of late term pregnant mares
-eliminate infected tall fescue from broodmare fields
-use tall fescue varieties without the toxic endophyte
-use other grasses in paddocks

Question 15

When does ergot alkaloid production increase?

Answer 15

when the plant is actively growing (April, May, June)

Question 16

When does ergot alkaloid production decrease?

Answer 16

when the plant is dormant (winter)

Question 17

What time of year is there more risk to mares foaling?

Answer 17

late spring (rather than Jan. and Feb.)

Question 18

Domperidone

Answer 18

a drug that will speed up foaling (won’t reverse the effects on the foal but will get the foal out asap)

Question 19

EquineLeukoencephalomalacia (ELEM)

Answer 19

central nervous system dysfunction associated with brain damage
-“moldy corn poisoning”

Question 20

Symptoms of ELEM

Answer 20

-ataxia
-circling/head pressing
-recumbency
-death

Question 21

Treatment of ELEM

Answer 21

no significant treatment, but supportive therapy

Question 22

What specific mold causes ELEM?

Answer 22

fusarium moniliforme (a type of myotoxin)

Question 23

Fusarium moniliforme

Answer 23

-mycotoxin
-produces fumonisins

Question 24

What animal is especially sensitive to fusarium moniliforme?

Answer 24

horses (more than cattle/swine/etc.)

Question 25

What does mold usually associate with?

Answer 25

poor growing conditions (drought, high humidity, flooding, etc.)

Question 26

Do fines or whole kernels have higher concentrations of mold and why?

Answer 26

fines doe because the moldy corn kernels break more easily

Question 27

How can ELEM be prevented?

Answer 27

testing corn used in horse feeds, and contaminated corn should not be put in those horse feeds

Question 28

What do blister beetles produce?

Answer 28

cantharidin

Question 29

Symptoms of blister beetles

Answer 29

-contact irritant-mouth and GI (causes blisters) -affects kidneys and heart -cardiac irregularities -death

Question 30

What are the first signs of blister beetles?

Answer 30

mouth blisters and GI upset (colic/diarrhea)

Question 31

How many grams of beetles are considered toxic?

Answer 31

4-6 grams (not a lot)

Question 32

When are horses exposed to blister beetles?

Answer 32

-alfalfa hay -beetles are attracted to flowers

Question 33

When is contamination more likely occuring?

Answer 33

during flowering

Question 34

When do beetles become adults?

Answer 34

in late spring/summer

Question 35

Where are blister beetles less common?

Answer 35

in cooler climates

Question 36

Selenium

Answer 36

an essential nutrient found in the soil (trace mineral)

Question 37

Where in the US is selenium soil distribution low?

Answer 37

-north midwest -florida -north west coast -canada

Question 38

When may horses be deficient in selenium?

Answer 38

when they are fed forage only diets in selenium low parts of the country

Question 39

Who is selenium deficiency most commonly identified in?

Answer 39

in neonates from dams in low Se areas that are not receiving fortified grain mixes

Question 40

What else can be involved in Se deficiency?

Answer 40

vitamin E deficiency

Question 41

What can Se deficiency cause?

Answer 41

nutritional muscular dystrophy (White muscle disease)

Question 42

Symptoms of Se deficiency

Answer 42

-weak foals when born -foals become weak when exercised -skeletal and cardiac muscle affected -white muscle disease

Question 43

How to prevent Se deficiency

Answer 43

provide adequate Se diets

Question 44

How narrow/wide is the margin between Se deficiency and Se excess?

Answer 44

very narrow (most narrow margin nutrient)

Question 45

Symptoms of chronic toxicity of Se

Answer 45

loss of hair and hooves

Question 46

Toxicity of Se affects what?

Answer 46

the bonding in certain sulfur containing amino acids

Question 47

When does chronic Se excess/toxicity exposure occur?

Answer 47

-consumption of Se accumulator plants in high Se areas -over supplementation

Question 48

When is Se toxicity relatively uncommon (unless oversupplmented)

Answer 48

KY

Question 49

Symptoms of acute Se toxicity

Answer 49

-muscle dysfunction -cardiac dysregulation -death

Question 50

When does acute Se toxicity exposure occur?

Answer 50

injectable Se overdose

Question 51

What are some other feed related problems in horses?

Answer 51

-feed contamination by antibiotics/growth promoting compounds used in other species -feed mixing errors that add too much of a nutrient -feed contamination by rodents/wildlife