Feeding and Nutrition I&II

Hindgut fermenters

Horses are non-ruminant herbivores

Only one compartment stomach

But have to digest plant fiber, large cellulose from grass and hay

Microbial fermentation in the cecum

Unlike ruminants which digest fibers by use of multi-chamber stomach, horses, use ___ to break down cellulose

Prefer to eat __ of food steadily throughout the day

Small amounts

Horses don’t have a __

Galbladder

Horses poop automatically when

Stomach is full

Horses are unable to

Regurgitate, vomit, and belch

Long, complex, large intestines and microorganisms in intestines can be upset by rapid changes in feed

Susceptible to colic which is a leading cause of death in horses

Require clean, high quality feed, provided at regular intervals and not subjected to abrupt changes

Sensitive to mold and toxins

Digestion of horse

Esophagus > stomach > small intestines > cecum > large colon > small colon > rectum > anus

Animal selects forage and pick up food with sensitive prehensile lips

Forage nipped with incisors and group by premolars and molars before swallowing

Esophagus

Enters stomach at acute angle, creating a one-way valve and powerful sphincter mechanism at gastro-esophageal junction

Horses cannot vomit

Area of choke

Stomach

• Small for horse’s size

• Capacity only 4 gallons/15 liters

• Works best at 2 gallons

• Several small feedings per day

• Empties when 2/3 full whether processed or not

Stomach capacity

4 gallons/15 liters

Stomach works best at

2 gallons

Stomach empties when __ whether processed or not

2/3 full

Small intestine

• 50 – 70 ft or 15 to 21 meters, holds 10 – 12 gallons or 38 – 45 liters

• Major digestive organ where 50 – 70% of nutrients are absorbed

• Bile from liver, enzymes from pancreas and intestines empty in here

• No gallbladder, bile flows constantly so horse provided with fodder in several small feedings

Cecum

• 1^st section of large intestine known as water gut or hindgut

• Blind end pouch 4ft/1.2 meters, holds 7 – 8 gallons/26 – 30 liters

• Small intestine opens into __ where cellulose plant fiber is fermented by microorganisms for approximately 7 hours

• Microbes produce vitamin K, B-complex, proteins and fatty acids

• Change diet slowly so microorganisms able to modify and adapt to new feedstuffs

Cecum also known as

Water gut or hind gut

Large colon, small colon, rectum

• Make up remainder of the large intestine

Large colon

• 10 – 12 ft/3 – 3.7 meters and holds 20 gallons/76 liters of semi-liquid matter

• Absorption of carbohydrates broken down from cellulose

• Due to twists and turns common site of colic due to impaction

Small colon

10 – 12 ft/3 – 3.7 meters, holds about 5 gallons/19 liters where majority of water absorbed and fecal balls are formed

Rectum

1 ft long, acts as holding chamber for waste which is expelled from the body via anus

Horses need approximately __ in feed daily depending on age and level of work

1.5 – 2.5% of its body weight

Feed for old horses

1.5%

Feed for younger, active horses

2.5%

Horses that are __ prone to obesity while __ need great deal of food just to maintain slim build

• “Easy keepers”

• “Hard keepers”

Easy keepers

Grows fat fast

Hard keeper

Doesn’t gain much weight from eating

Feed horses __ several times daily unless in full-time pasture and provide __ at all times

• Small quantities

• Ffesh, clean water

Horses not ridden daily or subjected to stress can obtain adequate nutrition on

• Pasture or hay alone

• 10 – 12 gallons/day

• Free access to salt block or loose salt

Horses and ponies on regular work need ration of __

Voth forage and concentrate

Improper feeding may develop __ particularly if given spoiled feed, excessive, abrupt changes of ration

Colitis or laminitis

Ponies develop __ due to an imbalance of nutrients and __ if overfed

• Growth disorders

• Osteochondrosis

Equines require 5 main classes of nutrients to survive

• Water

• Energy (fats and carbohydrates)

• Proteins

• Vitamins

• Minerals

Makes up between 62 – 68% of the horse’s body weight

Water

Horses can only live in a few days without water

Dangerously dehydrated if they lose 8 – 10% of their natural body water

  Average horse (1,000 lbs / 450 kgs) drinks

10 – 12 gallons water/day

More so during hot weather, eating dry feed, consuming high levels of salt, potassium, and magnesium

• Hot weather causes horse to sweat

• Salts need to be diluted to prevent kidney stones

Hard working or lactating, water requirement

4x greater than normal

Spends 1 – 8 mins in drinker/day spread out in 

2 – 8 episodes

Feeds eating mixed with saliva to make __ that can easily be swallowed

Moist bolus

Horses produce

• 8 gallons of saliva

• 4 gallons of pee

Nutritional source of energy are fat and carbohydrates

Carbohydrates are metabolized more easily

Heavily exercised, growing, pregnant, or lactating horses need __

Increased energy and proteins

Too much energy in diet with not enough exercise makes horse __

Too high-spirited and difficult to handle

Plants low in fats

9 megacalories per kg of energy

Makes fat difficult to digest and utilize in large quantities

Absence of gallbladder to store bile

Can only have __ in diet without developing diarrhea

15 – 20% fat

Carbohydrates are in the form of

Hay, grass, or grain

Soluble CHO such as starches and sugars broken down into __ in __and absorbed

• Glucose

• Small intestine

Insoluble cellulose is fermented in the __ and broken down into __

• Cecum and large colon

• Volatile fatty acids

Soluble CHO found in

Corn (highest), barley, oats

Forages __ soluble CHO

6 – 30%

Large amounts of starch or high sugar feeds can cause __

Indigestion, colic, fatal colitis or laminitis

Critical building block for muscles and other tissues such as muscle, blood, hormones, hooves, and hair cells

Proteins

Main building block of proteins

Amino acids

Proteins can be found in

Alfalfa and Legumes

Adult horses require __ protein in their diet, __ in lactating mares and young foals

• 8 – 10%

• Higher

Horses not subjected to hard work and extreme conditions have more than adequate amounts of vitamins if

Given fresh, green, leafy forage

Low quality feed and horse under stress or not eating well needs __

Vitamins supplement

Grain required

Vitamin supplementation

Minerals required for maintenance and function of skeleton, nerves and muscles

• Ca, P, Na, K, Cl

• Trace minerals Mg, Se, Cu, Zn, and I

Animals on hay and pasture receive adequate amounts of vitamins except

NaCl

Pastures deficient in trace minerals result to __

Deficiency diseases

Adult horses Ca:P ratio

1:1 or 2:2

Foals Ca:P ratio

3:1

• especially in their first 3 - 4 years

Hard work increases need for minerals as sweating depletes Na, K, Cl

Supplementation for horses in intense training especially in hot weather

Adult horses eat __ of their body weight in dry feed each day, approximately __

• 2 – 2.5%

• 25 lbs / 11 kg

Foals less than 6 months eat __ of their body weight each day

2 - 4%

Solid feeds in 3 categories

• Forages

• Concentrates

• Supplements

Animals’ diet should be 50% forage

Can be 100% forage if the horse doesn’t do anything and its good quality

Animals requiring more energy

Increase grain, decrease forage

Forage should never go __ of horse’s body weight per day

Below 1%

Forage

• Commonly known as “roughage” plant materials

• Legumes or grasses

  •   In pastures or hay

Nutrients in forage depend upon

Maturity of grasses, fertilization, management, and environmental conditions

Grasses

• Timothy, brome, fescue, coastal Bermuda, orchard grasses and Kentucky grass

• Beet pulp high in Vit E

Legumes

• Clover and alfalfa higher in protein, Ca, and energy than grasses

• __ hays higher protein than grass hays, higher mineral particularly Ca but incorrect Ca:P ratio

Hay

• Dried mixture of grasses and legumes

  • Cut, dried, and baled for storage

• Most nutritious when cut before seed heads fully mature and stems become tough and thick

• Color good indicator of nutrients, smell and texture important indicators of quality

• Alfalfa hay compressed into pellets or cubes

• Processed hay more consistent quality and more convenient to ship and store

• Can overfeed and choke

• Can be soaked to produce pulp of thick slurry

Haylage

• Also known as round bale silage or grass sealed in airtight plastic bags

• A silage, therefore, must remain completely sealed as holes and tears can stop preservation properties of fermentation

  • Mold and spoilage

Straw or chaff

• Little nutritional value other than providing fiber

  • Used as fillers and slow down horses that eat too fast

• Add additional fiber when horses fed mostly concentrated feeds

• More useful as beddings

Forages

• Grasses

• Legumes

• Hay

• Haylage

• Straw or Chaff

Concentrates

• Grains

• Oats

• Corn

• Barley

• Wheat

• Mixes and pellets

Grains

Whole or crushed most common form of concentrated feed

Oats

• Most popular grains for horses

• Low digestible energy and higher fiber content than most grains

• Form loose mass in stomach, well-suited to equine digestive system

• More palatable and digestive than other grains

Corn

• Maize

• 2^nd most palatable grain

• Twice as much digestible energy than oats and low in fiber

• Easy to overfeed causing obesity

• Moldy corn poisonous to horses

•   Aspergillus mold

  • Produces aflatoxin that might cause liver cancer

Barley

• Processed to crack seed hull and allow easier digestibility

• Fed in combination with oats and corn

  • COB

Wheat

•   Generally not used as concentrate

• __ bran added to diet for supplemental nutrition in form of bran mash

• High in P, with laxative effect

Mixes and Pellets

• Various grains and additional vitamins and minerals supplements, complete premix feed

• Easy to feed and predictable nutritional quality

• Pelleted form or grains in their original form

Molasses

• Added as binder to keep down dust and increase palatability, called sweet feed (US) and coarse mix (UK)

• Pelleted or extruded feeds (‘nuts” in UK) easier to chew and results in less wasted feed but more expensive

Supplements

• Horses on good hay and pasture does not need

• Horses subjected to stress due to age, intensive athletic work or reproduction may need additional nutrition

  • Extra fat and protein with vitamins and mineral supplements

• Soybean meal common protein supplement, 44% CP

  •   High quality protein with right ration of essential amino acids

• Cottonseed meal, linseed meal, and peanut meal not as common

Feeding practices

• Most horses need only quality forage, water, and salt or mineral block

  • Grains and other concentrates not necessary

•   Horse need measured by weight not by volume

• Provide 3 small feedings per day instead of one or two large ones

Actual amounts of feed depend on

• Age of horse

• Climate

• Work to which the animal is put

• Genetic factors

Age of horse

Foals need more feed

Climate

Animals eat more in a cold climate

Work to which an animal is put

If the animal doesn’t do anything, it doesn’t need a lot of food

Genetic factors

• Hard keeper

• Easy keeper

Hard keeper

Good doers can thrive on small amounts of food, but are prone to obesity and health problems if overfed

Easy keeper

Poor doers, prone to be thin, require considerably more food to maintain a healthy weight