Exam 2: Lecture 14 - Equine nutrition 2

Question 1

what are the problems with bermuda grass even though it is excellent pasture

Answer 1

1. can rapidly become fibrous and cause impaction colic when it is tall and mature
2. coastal bermuda can cause ileal impactions in horses

Question 2

what is the problem with endophyte fungus present in endophyte-infected fescue

Answer 2

1. poor growth
2. prolonged gestation, thickened placenta, agalactia (cant produce enough milk) in mares
3. increased foal mortality

Question 3

what are the problems with alsike clover

Answer 3

1. linked to liver disease in horses
2. neurological signs (hepatic encephalopathy)
3. wasting
4. photosensitization

Question 4

what is the problem with red clover

Answer 4

occasionally contaminated with fungus called rhizoctonia leguminicola

Question 5

what does the fungus, rhizoctonia leguminicola, cause in horses

Answer 5

produces slaframine which is a toxin slowly degraded during storage of hay, also a source of phytoestrogens

Question 6

what is a large contributor of laminitis

Answer 6

high concentrate diet/grain overload

Question 7

how do high concentrate diet/grain overload cause laminitis

Answer 7

1. delivery of too much starch to large intestine
2. high starch fermentation can lead to diarrhea, colic, or laminitis

Question 8

how do we prevent laminitis and high concentrate diets

Answer 8

1. limit concentrate feed to a max of 0.5% of body weight
2. always feed at least 50% of hay

Question 9

T/F: digestibility of starch in small intestine very high for some grains

Answer 9

true!

Question 10

how do large amounts of starch reaching large intestine change the local environment

Answer 10

1. high amounts of grain/fermentable carbs lower intestinal pH
2. lower pH = more gram-negative bacterial die (means there are more gram positive and produce lactic acid)

Question 11

what is the result of too much grain/fermentable carbs reaching large intestine

Answer 11

1. changes in bacterial populations can result in endotoxin release
2. endotoxins
3. diarrhea, colic
4. laminitis

Question 12

T/F: high levels of non-structural carbs (NSC, soluble carbs) in forages can cause laminitis

Answer 12

true!!

Question 13

T/F: ideally fructans, sugars, and starch would all be digested in SI but 30-50% reaches LI where they are rapidily fermented

Answer 13

true

Question 14

what are the problems caused from excessive NSC in LI

Answer 14

1. overgrowth of bacteria that ferment starch and fructans
2. destruction and inflammation of gut wall
3. damage allows absorption of toxins
4. causes laminitis

Question 15

Should WSC, ESC, and ESC + starch be low or high for laminitic horses

Answer 15

ESC should be low
WSC should be low
ESC + starch should be low (<10%)

Question 16

when do fructans accumlate

Answer 16

when rate of photosynthesis exceeds use of energy for growth in plants

(cool weather, after a frost, drought, later in the day)

Question 17

T/F: there are the highest levels of fructans in fall glasses

Answer 17

false! highest levels are in late spring

Question 18

why are fructans dangerous

Answer 18

1. not digested by mammalian enzymes
2. escape SI, rapidly fermented in LI
3. more dangerous than starch

Question 19

what is laminitis

Answer 19

inflammation of laminae of hoof wall that causes pain, separation, rotation/sinking of pedal bone

Question 20

experimentally, how has laminitis been induced

Answer 20

starch 18 g/kg DM

fructans 10g/kg DM aka 5kg per 500kg horse

Question 21

T/F: pasture grasses can accumulate >400g fructans/kg DM

Answer 21

true!!!

Question 22

how can we avoid pasture-associated laminitis

Answer 22

1. restrict grazing, especially in spring
2. supplement with hay made from mature grasses or legume containing hay
3. NSC content of hay can be reduced by about 30% by soaking in water for 30-60 mins
4. analyze grasses and hay for NSC
5. avoid obesity
6. horses with previous laminitis episodes especially at risk

Question 23

T/F: NSC less than 12% may contribute to issues in problem horses

Answer 23

false!! NSC ABOVE 12%

Question 24

what contributes to almost half of the cases of laminitis

Answer 24

grazed lush pastures!! (45.6%)

Question 25

what are the problems with caring for laminitic horses

Answer 25

1. clients have only one big pasture 2. no stalls available 3. short supply of hay 4. lack of owner compliance 5. cost involved in providing ideal care

Question 26

what are the costs involved in providing ideal care of horses with laminitis

Answer 26

1. make a dry lot 2. buy quality hay and have a nutrient analysis performed 3. pay for regular farrier care 4. pay for meds and follow up on case

Question 27

which forage is associated with ileal impactions in horses? A. Tall fescue B. Alsike clover C. Bermuda grass D. Red clover

Answer 27

C. Bermuda grass

Question 28

what are the predisposing factors of cribbing

Answer 28

1. stall weaning vs pasture weaning 2. stall housing following weaning 3. feeding concentrates 4. lack of time at pasture 5. lack of straw bedding in stall

Question 29

what are the problems with cribbing and what are the treatments

Answer 29

problems: causes wear and tear on teeth treatment: increase dietary fiber, remove ledges, electric fence, creosote, dog collar, cribbing collar, sx

Question 30

T/F: Gastric ulcers are most common in performance horses and foals

Answer 30

true!

Question 31

where do gastric ulcers more frequently occur in horses

Answer 31

non-glandular stratified squamous mucosa

Question 32

what are the risk factors of gastric ulcers

Answer 32

1. intense exercise 2. increased stall time 3. meal feeding 4. not having hay available ad libitum

Question 33

T/F: feeding alfalfa and aloe vera juice can be protective for gastric ulcers

Answer 33

true!!

Question 34

what are the ways prevention of gastric ulcers

Answer 34

1. diet 2. management 3. treatment

Question 35

how do we prevent gastric ulcers with diet

Answer 35

1. feed alfalfa or pasture (alfalfa buffers acid) 2. roughage continuously available stimulates saliva which is rich in bicarb 3. avoid large grain meals

Question 36

how do we use management for prevention of gastric ulcers

Answer 36

reduce stress and increase turnout time

Question 37

what can we use for treatment of gastric ulcers

Answer 37

gastrogurd (omeprazole) and ulcergard

Question 38

which type of carb in grass can contribute to excessive LI fermentation and may result in laminitis? A. starch B. fructans C. cellulose D. glucose

Answer 38

B. fructans

Question 39

what is heaves in horses

Answer 39

allergic respiratory disease of horses characterized by chronic cough, nasal discharge, and respiratory difficulty

Question 40

what are other names for heaves

Answer 40

recurrent airway obstruction/COPD/broken wind/emphysema

Question 41

how can we help feed horses with heaves

Answer 41

1. avoid dusty, mold hay 2. feed cubes 3. soak hay 4. avoid hay storage above horses in barn 5. pasture the horse 6. hay gain system (steam sterilizes hay)

Question 42

how long do we need to soak hay for horses with heaves

Answer 42

60 mins in cold water, 30 mins in warm water

Question 43

what is the problem with soaking hay

Answer 43

it will leach out other nutrients!!! about 30% reduction in sugar content and >50% reduction in potassium

Question 44

what is vitamin E deficiency in horses caused by

Answer 44

an issue with poor quality hay and grain

Question 45

what can vitamin E deficiency cause in horses

Answer 45

1. equine degenerative myeloencephalopathy 2. equine lower motor neuron disease

Question 46

what do we see in horses with equine degenerative myeloencephalopathy

Answer 46

1. possible hereditary component or vit E deficiency 2. intracellular damage via oxidation 3. ataxia, proprioceptive deficits, weakness and spasticity of all four limbs with the hind limbs often being the most affected

Question 47

what do we see in horses with equine lower motor neuron disease

Answer 47

1. older horses deficient in vit E for 18 months or longer 2. neurodegenerative disorder of the horse characterized by progressive weakness, fasciculations, muscle wasting, and weight loss

Question 48

why does food get stuck in the esophagus in horses

Answer 48

esophagus passes thru the thoracic inlet and behind the base of the heart

Question 49

when is choke/obstruction common in horses

Answer 49

1. if horse bolts food with chewing properly 2. more common with pelleted feedstuffs, cubes, beet pulp

Question 50

what does choke look like in horses

Answer 50

horse extends head and neck and may have nasal discharge

Question 51

how can we prevent choke in horses

Answer 51

wet to prevent - feed gruel or mash

Question 52

what is leukoencephalomalacia in horses

Answer 52

fumonisin toxicity that causes neurological signs

Question 53

why do we see neurological signs with leukoencephalomalacia

Answer 53

because there is liquefactive necrosis of the cerebral white matter

Question 54

what are the clinical signs we see with leukoencephalomalacia

Answer 54

progressive ataxia, depression, anorexia, delirium, aimless wandering, recumbency, coma and death can occur 12 hrs to 1 weeks after onset of signs