Equine Nutrition Flashcards

Question

What are the fat soluable vitamins?

Answer 1

- Vitamin K - Vitamin A - Vitamin D - Vitamin E

Answer 2

• Essential fatty acids: linoleic acids and arachidonic acid • Horses can form these FA, so not necessary from the diet • Fats are 2-6% of the meal (DM) usually • Can be increased up to 10% (20% of the daily kcal) gradually with a palatable oil •Also add vitamin E • May be preferable to highly (Due to risk of oxidation) digestible carbohydrates when energy demands are high • Less risk of colic and laminitis

Answer 3

• Calcium and phosphorus comprise 70% of all the minerals in the body. • The bone is the storage pool for these minerals (the ionized calcium in the blood remains constant by drawing from the bone if needed) • P is important for energy metabolism (ATP), membrane function and enzyme regulation • Ca is important for neural function, enzyme activity, cell signaling etc

Answer 4

- Can bind calcium and can have implications on skeletal health in growing foals and mares. - Calcium is mostly absorbed in the small intestines whereas phosphorus is mostly absorbed in the large intestines

Answer 5

* Excess phosphorus impacts calcium absorption more than the other way around * The recommended ratio (Ca:P) is 1:1 -5:1 in the mature horse

Answer 6

• Horse has an appetite for salt and will consume adequate amounts if it is available

Answer 7

Excess salt intake -\> drinking more water -\> more urine • Horses confined to the stall may eat salt out of boredom, may drink more and urinate more • Wet stall Salt toxicity - if water is not available or palatable. - colic - diarrhea - weakness - neuro signs

Answer 8

Slow ingestion of saline free water? If too rapid, cellular edema can occur - Neuro signs

Answer 9

• Uncommon as long as salt is available • May cause weakness • Decreased sweating • Decreased performance • Decreased sweating • Decreased lactation • Pica

Answer 10

Important for normal cardiac function, acid base balance, renal function, neural function. Dependent on activity and physiologic/ Pathologic state.

Answer 11

hypoklemia can cause: Inappetence, fatigue, weakness, lethargy. Can occur with excess sweating (increased aldasterone secretion, increased Na+ retention, increased potassium excretion), diuretics, diarrhea.

Answer 12

- Closely adheres to calcium and phosphorus. - Dietary deficiency is uncommon, high P may reduce absorption as well as hypomagnesemic tetany.

Answer 13

Can cause paralysis of limbs, grass tetany is example. Treatment: Magnesium and Calcium supplementation. More susceptible: Lactating Mares, Fasted animals in transport, animals exposed to young pastures or K+ enriched pastures.

Answer 14

Adenyl cyclase activity, which is required for parathyroid hormone release. ( Which is important for absorption of calcium)

Answer 15

Paradoxically, both excess and deficiency can cause clinical signs of hypothyroidism.

Answer 16

Iodine is important to make triiodothyronine and thyroxine. Low iodine -\> low thyroid hormone production Excess iodine -\> negative feedback for TSH release from pituitary -\> Low thyroid hormone production. You can also see Goiter and hypothyroidism in these patients.

Answer 17

- dry coat - alopecia - impaired growth - decreased bone mineralization - Lethargy, inappetence. - Cold intolerance - Goiter (swelling of thyroid gland)

Answer 18

Copper is important as a cofactor for Super Oxide Dismutase (SOD). Copper promotes oxidation on its own. Copper excess can cause liver and renal damage.

Answer 19

– Collagen/ elastin synthesis (dematuration) – Iron mobilization (deficiency-\> anemia) – Melatonin synthesis (reddening of black hair coat

Answer 20

It inteferes with copper absorption and can cause copper deficiency

Answer 21

• A cofactor to many enzymes including SOD therefore an antioxidant • Zinc excess is uncommon, but zinc can interfere with copper absorption • Zinc deficiency • Parakeratosis in the lower limbs • Decreased food intake

Answer 22

In foals -\> excess may cause joint disease

Answer 23

• Iron deficiency is uncommon • Supplementation: given to race-horses and foals • Can be harmful in foals and is unnecessary (can cause liver failure in foals)

Answer 24

Synergistic effect as antioxidants (low amounts in one require supplementation of the other) • Prevent lipid peroxidation in the cell membranes- glutathione peroxidase

Answer 25

Selenocysteine

Answer 26

Vitamin E and Selenium deficiency

Answer 27

Clinical signs • Lethargy • In foals- unable to curl tongue to suckle • May cause aspiration pneumonia – if tracheal muscles are affected Yellow fat disease- a condition that causes steatitis Steatitis- inflammation of fat stores.

Answer 28

- Low Vitamin E concentration ( plasma levels can be variable) - Can biopsy liver and muscle stores (avoid fat stores, they are not reliable) - High Creatine Kinase, and AST (shows recent muscle damage) - Low RBC glutathione peroxidase (selenium deficiency)

Answer 29

• Selenium and vitamin E can be given prophylactically by muscular injection to foals at birth * Supplement in creep feed (feed Offered to nursing foals) * Supplement the mare’s feed • Vitamin E excess is uncommon (could reduce absorption of other fat-soluble vitamins Toxicity is potential issue -\> 5-10x requirement is toxic (narrow safety range)

Answer 30

- High in leafy greens. * Usually sufficient in fresh pasture * Storage can cause degradation/oxidation * Heat processing can cause degradation * Diets with high fat/oil- increased vitamin E requirement to prevent oxidation.

Answer 31

- Fat soluble vitamins A, D, E, and K - Generally present in adequate amounts in feed • Although can be reduced if stored for long periods - Greater risk for toxicity especially for vitamins A and D due to slow rates of excretion - Fat soluble vitamins share the same absorption mechanisms and can compete with each other

Answer 32

• Water soluble vitamins are rarely deficient or in excess • Can be synthesized endogenously or by colonic microbes • Excess is filtered in the urine and excreted from the body • Requirement can increase if water intake is high or high energy requirements

Answer 33

* Grain mixtures are usually fortified with vitamins * High energy-\> be careful with over-supplementation (can be Expensive) * Additional vitamin supplements could be beneficial if: * Hay/ feed quality is poor or stored for long * Colic/GI disease -\> dysbiosis (less bacterial microflora so less synthesis of vitamins so supplements are important.) * Antibiotics -\> dysbiosis (destruction of gut microflora)

Answer 34

• Species that are commonly found in human probiotics or yoghurt include Lactobacillus, Bifidobacterium and Enterococcus are only 1% of the normal equine GI flora • Firmicutes are most abundant, but not used in most commercial probiotics • Most equine GI disease affect the large intestines so if bacteria does not survive it won’t be useful • Probiotics may not be safe in very young horses (\<2 mo) • Most evidence suggest that some probiotic Lactobacillus strains may survive the GI tract, but do not colonize it • Little evidence of probiotics in horses at present (especially in healthy horses)

Answer 35

Feed to maintain an ideal BCS • May need to increase amount of concentrate in breeding (showing off for female) • Avoid obesity- poor fertility (poor sperm quality when obese)

Answer 36

Maintain BCS of 5-6 • More issues with under nutrition rather than over nutrition • No increase in food intake necessary until last trimester (week 16) of pregnancy

Answer 37

During last trimester increase 12-20% in intake • For Quarterhorse/ Thoroughbred mares an expected increase of 150-200 lbs. in bodyweight during pregnancy

Answer 38

Protein requirement would increase to 8% in the first trimesters and 10% in the last trimester. this is because more protien is needed in the final trimester to produce the fetus' tissues and help support lactation. * High protein feed: legume grass, legume hay * Can balance a meal with grass hay and high protein grain (12% protein DM)

Answer 39

* Protein requirements increase to 13% * Can be balanced with a combination of legume hay or legume grass * If legume hay is provided, grain protein can be 12% * If grass hay is provided, grain protein needs to be at least 16%

Answer 40

• Grass hay is lower in calcium so may need to supplement • Legume hay has enough calcium, but may need to supplement phosphorus

Answer 41

• The main diet is the mare’s milk; however will show interest in other food such as the mare’s grain and creep feed • Creep feed: the feed that is offered to suckling animals (also beef, swine, small ruminants) to support growth in addition to milk • Creep feed would typically include corn, oat, barley

Answer 42

Most foals would wean between 3 and 7 months. You would start to introduce creep feed at 1-3 months.

Answer 43

* Could be the result of accelerated growth * Genetic trait * Common conformational abnormalities: * Toe in * Straight fetlock * Nutritional factors: excess and/or deficiency * Vitamin A * Vitamin D * Calcium * Phosphorous * Mg * Copper * Zinc * Other Causes * Energy excess: Above 120% the requirement according to the NRC * Protein excess? No evidence in foals (or dogs) * Carbohydrate excess? • Increased insulin secretion * Affects growth plate structure

Answer 44

Prevention: * Maintain an ideal BCS (4/9) * Ideal growth rate estimates: * Suckling foals \<1.1 kg per day * Weanling foals \<0.75 kg per day * Prevent rapid growth * Early intervention as needed

Answer 45

Rest / Maintanence: 4-6 (0.33 x kg bodyweight) Performance: 5-6 ( 1.4 x (DER for rest)) Ranch work: 4-5 (1.6 x (DER for rest))

Answer 46

Halter Competition/ Pleasure Horse: 5-6 (1.2 x (DER for Rest)) Race Competition (3 day events): 4-5 (1.9 x(DER for Rest))

Answer 47

* Combination of carbohydrate sources: * Legume grass, green grass, and grains [high energy] * VFA * Oils [10% dry matter] 20% of all energy intake Protein: • Protein requirements are increased in performance horses • Protein is thermogenic • Can negatively affect performance in warm weather • $$$ • High protein feed: alfalfa (legume hay), grass hay, oat hay, grain

Answer 48

This will decrease performance

Answer 49

Do not feed more grain than forage.

Answer 50

• More activity -\> more sweat-\> more electrolyte loss * Electrolytes of concern: Na, Cl, K, Mg, Ca * Legume hay provides Ca, Mg, K but low in Na * Grains- do not provide much electrolytes * Salt blocks * Added salt if sweating for over an hour 1-2 oz per hour

Answer 51

* Water: 30-40 L per day (depends on temperature and activity) * Higher requirement if main diet is dry hay rather than pasture/forage * Water needs to be clean * Restrict access is horse is hot/water too cold ( to prevent colic) * 2-3 L every 15-30 minutes

Answer 52

* Able to feed on lignin-rich, low energy food- Slower GI transit allows increased fermentation * Evolved to survive in a semi-arid mountainous environment * Forager

Answer 53

• Energy requirements are also lower than horses (50-70% of a similar size horse) • Can become obese and develop hyperlipidemia, laminitis and other metabolic complications if fed with horses

Answer 54

- Typical diet would include wheat or barley straw or stover (leaves and stalks of crops such as corn) • Straw can be fed ad-lib - Low energy density

Answer 55

Dental health- important as they consume very high fiber food • Pregnant or lactating jenny (female donkey) and growing donkeys require supplementation with higher energy and protein feeds • Alfalfa • Beet pulp • Rice bran • Supplementation feed should be given in small amounts and mixed with straw • Avoid concentrates in donkeys- high risk for laminitis and colic

Answer 56

* Water should be available in all times when possible * While donkeys are quite resilient and resist dehydration, this is not recommended DON'T DEHYDRATE DONKEY DDD

Answer 57

Full medical history * Housing/environment- inspect if possible * Reproductive history * Detailed diet history * What is being fed, how often, any supplementation * How is the feed offered * Feeding behavior

Answer 58

* Bodyweight can be measured on walk-in scales or estimated: * Lb Bodyweight= Heart girth (in)2 X Length (in) /330 * Kg Bodyweight= Heart girth (cm)2 X Length (cm)/11800 * Heart girth – measured behind elbows at expiration * Length- point of the shoulder to tuber ischii

Answer 59

Most nutrients cannot be adequately determined with lab tests/blood tests • Albumin- can be reduced if protein status is poor, acute inflammation or liver failure • Albumin half life is long (19.4 days) therefore may not reflect acute changes • Decreased creatinine/BUN can indicate poor muscling and protein intake

Answer 60

* Physically assessing feed: appearance, smell * Feeds should be in sealed container * Appropriate temperature and moisture * Oil- sealed, protected from light and high temp * Hay- protected from rain/moisture * Alfalfa – inspect for toxic blister beetles (sometimes present) * Hay – leaf to stem ratio * First cut is less digestible, and leaves are smaller (less nutritious, more legnin) • Second and third cut- richer and more digestible, longer leaves * Hay quality – color (bright green is best; dark brown not good); mold (take core sample and send for testing to get representative sample) * Weigh the feed (not volume) (volume can be misleading) * Estimate pasture/grass intake * Can send a sample to lab analysis

Answer 61

- Rhabdomyolysis is damage/destruction of muscles - Usually the result of extreme exercise and excretion - Especially in race-horses- Thoroughbred, standardbred, Arabian - Results in severe muscle damage that is extensive enough to have considerable metabolic implications

Answer 62

It is possible that horses on a high fat diet and low antioxidant intake are at higher risk of exercise-related oxidative damage - Also reported in sled dogs/sporting dogs and wildlife during capture and transport, and in humans - Can also result for other extensive muscle damage such as trauma, burns, snake bites, electrocution, heat stroke - Other causes: - Vitamin E/ selenium deficiency - Electrolyte imbalance (sweat, heat) - Underlying disease (fever) - Polysaccharide storage myopathy-glycogen storage disorder - Quarter horses - Warmblood - Draft horses

Answer 63

Muscle pain • Swollen muscles  Stiff gait  Myoglobin in the urine may cause red-brown urine  Can progress to renal failure – tubular necrosis due to myoglobinuria  Potassium leakage from myocytes can cause cardiac arrythmia and even cardiac arrest! (Hyperklemia)

Answer 64

- Elevated serum creatine kinase - Elevated serum AST - Elevated serum potassium - Myoglobinuria

Answer 65

 Supportive care- fluids, adjust electrolytes, antioxidants?  Corticosteroids (if in shock)  Nutritional support:  Feed 1-2.5% BW/day  Limit starch to 10%  Limiting starch not only modifies fuel energy use in the muscle, but it also decreases excitability and nervousness  Increase fats (20-25% DE in fat)  Vegetable oils  Associated with decreased HR “calmness”  High fiber  A commercially prepared high-fiber, high-fat, low-starch diet should be offered on a regular basis  These diets are palatable, nutritionally balanced, and designed to maintain a horse’s weight - Reduce stress/ confinement - Allow regular exercise

Answer 66

Hyperlipidemia is common in overweight ponies and in mares  Horses may be thin whereas ponies are often overweight  Many times secondary to stress, disease, pregnancy, lactation or poor feed intake  Clinical signs:  Inappetence  Dullness  Depression  Poor feed intake  Colic  Can cause liver failure

Answer 67

 The pathogenesis is similar with other species:  Free fatty acids are mobilized to provide energy at a rate that exceed their metabolism (fatty acid oxidation or formation of ketone bodies)  Lipids are re-esterified to triglycerides  May accumulate in the liver where they are metabolized to energy  The fat accumulates in hepatocytes and can also cause clots/emboli in blood vessels

Answer 68

 Mortality- high  Treat primary illness  If anorexic- feeding tube is indicated to reverse catabolic state  Insulin- can work with ponies – can stimulate peripheral lipoprotein lipases  Prevention is key!  Maintain an ideal BCS  Address disease and monitor intake  Provide high quality diet for mares during pregnancy and lactation

Answer 69

Colic is a general name for abdominal pain - Many possible causes - If colic is prevalent- check diet, dentition, parasite control - Impaction colic- usually in the large intestines, often can be palpated - Can be caused by: Indigestible food, Sand, pica, poor hydration  Signs of colic include:  Pawing  Rolling  Bloating  Sweating  Distress  Uneasiness  Loss of interest in food and water  Peculiar postures (sitting, stretching)  Absence of gut sounds

Answer 70

Treatment:  Soak food- divide to 3-4 meals  Provide soluble fiber- beet pulp  Wheat bran  Psyllium  Linseed  Provide salt blocks to avoid pica  Flunixin meglumine- reduces the cellular production of prostaglandins but can also mask signs  Gas colic- in large intestines, can palpate  The result of excessive fermentation and gas production  Can be the result of high energy feeds such as grain, lush forage  Sand colic-  Large intestines- hard to palpate  Suspect according to environment and sand in feces  Prevention:  Access to water  Dental health  Avoid excess grain/high energy forage  Slow transition to diet change  Avoid feeding when horses are ‘hot’ after exercise  Encourage owners to become educated on fed quality, dental care, vital signs and recognizing early signs of distress

Answer 71

- Equine colic may be considered medical when it can resolve without surgery, or surgical when there is an impaction that does not respond to medical care  Medical treatment is appropriate if the horse is mildly painful and the cardiovascular system is functioning normally  If evidence of intestinal obstruction with dry ingesta is found on rectal examination, a primary aim of treatment is to rehydrate and evacuate the intestinal contents  If the horse is very painful- pain must be addressed as pain can negatively affect GI motility  Address hydration and electrolyte abnormalities if present  A nasogastric tube may be passed to relive gas

Answer 72

 Laminitis results from disruption of blood flow to the laminae  These laminae structures within the foot secure the coffin bone to the hoof wall  Inflammation often permanently weakens the laminae and interferes with the wall/bone bond  In severe cases, the bone and the hoof wall can separate

Answer 73

Etiology:  Can be caused by certain toxins such as bacterial toxins  This can be the result of GI dysbiosis, nutritional factors, or an infection Excessive carbohydrate intake- incidental grain overload  Grains, green pasture  Gut microbial shift: not all carbohydrate will be digested in the small intestines, fermentation in the large intestines causes acidosis  bacterial die-off and release of endotoxins  Endotoxemia can cause and increase in TPR, colic (within 12-16 hours) laminitis (within 24 hours)  Clinical signs:  Lameness  Pain  Change in the hoof structure in chronic disease  Can be fatal

Answer 74

 Treatment:  Stop fermentation- mineral oil, laxatives  Walk/gentle exercise if not painful or too sick  Banamine  Toxin binding medications- antibiotic polymyxin B can be given IV before toxins cross to the blood; di-tri-octahedral (DTO) smectite (Bio-Sponge) under research  Prevention:  Avoid high sugar/water soluble carbohydrate feed  Soaking hay in water and then removing the water can help reduce the water-solublecarbohydrate that may contribute to dysbiosis

Answer 75

 Equine metabolic syndrome (EMS) is a characteristic collection of clinical signs and clinicopathologic changes in equids that places them at high risk for developing laminitis  Insulin dysregulation, the abnormal insulin response to oral or IV glucose is the hallmark of EMS  Most affected horses are obese, but insulin dysregulation can occur in thinner animals as well  increased regional adiposity in the neck and tailhead regions is typical Hallmark sign: Hyperinsulinemia with normal blood glucose concentrations (insulin resistance) is the hallmark finding.

Answer 76

- Horses with EMS respond to high carbohydrate meals with an exaggerated increase in insulin and higher than normal blood glucose that tapers slowly  Associated signs include infertility, altered ovarian activity, and increased appetite  Can also cause hypertriglyceridemia, increased serum concentrations of leptin, and arterial hypertension  While the cause of this syndrome is not entirely known or understood, obesity appears to be an important risk factor

Answer 77

 Experimentally, high blood insulin levels lead to laminitis due to vasoregulatory actions  Insulin resistance can decrease nitric oxide production and promote vasoconstriction  EMS may be a predisposing factor for pituitary pars intermedia dysfunction (PPID; equine Cushing’s disease)  Diagnosis: oral sugar test (OST) or oral glucose test (OGT) (fasted for 3-12 hours, then given corn syrup and blood drawn at 60 mins, and 90 mins)

Answer 78

Glycemic index: the plasma/blood glucose response to ingestion of a measured amount of feed  The higher glycemic response typically produces a higher insulin response  Corn, oat, and barley all result in increase in blood glucose (BG) within 15 minutes - The glycemic index of hull-less oats is higher with a more rapid increase in BG (higher digestibility)  Barley is of low glycemic index  Pelleting and extrusion tend to reduce the glycemic index  Grass hay has a higher index than legume hay

Answer 79

 Over time, horses may adapt to high glycemic index foods  This results in higher insulin secretion and decreased insulin response  This has chronic negative implications  Appropriate diet: reduce high energy concentrates, fats can be included in small amounts, increase fiber and roughage  Pasture access should be eliminated or severely restricted until body weight is in the desired range  A muzzle could be used to limit feeding  Sudden feed restriction should be avoided- risk of hyperlipidemia/ Hyper TG

Answer 80

Slow steady weight loss After weight loss, previously obese horses will likely have lower energy requirements than their lean counterparts.  Exercise – moderate to allow gradual decrease in adiposity  Avoid overexcretion and rhabdomyolysis

Answer 81

Chronic kidney disease is relatively uncommon in horses  Common causes: high blood pressure, coagulopathies, pyelonephritis and tumors  Renal disease is typically progressive  Unfortunately, no clear diet recommendations- avoid high protein (legumes for example)  Protein \< 8%  Carbohydrate based diet  Adequate hydration

Answer 82

Some horses remain physically active and healthy well into their twenties and others become “geriatric” by mid-teens  Older horses may lose weight and muscle mass although obesity is not uncommon  17% of owners reported weight loss in their elderly horse within the last 12 months  If the horse does not have an underlying metabolic disorder, there may be a benefit to a high caloric density and increased protein diet  Consider the use of more digestible forage (less mature grass hay)  Consider including highly digestible fiber sources such as beet pulp/soy hulls as means to increase the energy intake  Soaking and throwing away the water to reduce as far as possible the water-soluble carbohydrate intake as these may contribute to risks for colic and laminitis

Answer 83

If there are no contraindications: oil as an energy source rather than cereal starch - especially for those animals not being exercised  If any cereals, other than oats, are fed make sure they are processed by cooking (e.g., steam flaking, micronizing) to make the starch more easily digested, reducing the risk of starch overload  Avoid feeding large grain-based meals: restrict meal sizes

Answer 84

 There are little data on feeding hospitalized horses and its association or effect on morbidity and mortality  However, plenty of data exists in people and other species to demonstrate that a catabolic state reduces prognosis  Nutritional intervention should be considered if the horse is not fed for longer than 48 hours in an animal with good physiological status  Less if obese, underlying metabolic disease, growing or very sick  Enteral nutritional support: a nasogastric feeding tube can be passed and used temporarily, or an indwelling esophageal feeding tube can be placed  The horse should be checked for gastric reflux before feeding

Answer 85

check for gastric reflux before feeding

Answer 86

 If the gut function is impaired, parenteral nutrition may be administered  The formula is custom made under a hood  Components used in formulating parenteral nutrition include:  protein in the form of amino acids  carbohydrates in the form of dextrose  lipids in the form of long chain fatty acids  May be safer to avoid in donkeys, ponies and other horses prone to hyperlipidemia  electrolytes and vitamins  The catheter, line and bag must be kept as clean as possible

Equine Nutrition Flashcards

(112 cards)