Feeding Standardbred Racehorses (Pacers, Trotters)

Racing standardbreds have different nutritional needs to gallopers or sprint horses. Pacers and trotters are traditionally worked a lot harder than gallopers. Studies have shown that standardbreds exert about 12 times more effort than a thoroughbred in the preparation period to racing fitness, and are raced, on average, about three times as often. Standardbreds also maintain their all-out speed for longer than gallopers in a race, requiring higher overall levels of fitness and stamina.

Many standardbreds are smaller framed horses, which combined with the physical stress and fatigue of long, hard training, reduces their capacity and appetite to consume large bulky feeds. Rations must be adapted to meet changing exercise needs and appetite limits as a horse progresses through a training program.

Traditionally, standardbreds were not trained and raced until three years of age. Younger horses are now subjected to strenuous training, increasing the need to provide higher energy, protein and mineral concentrations in their rations to meet demands for growth, development and exercise. An inadequate intake of energy will reduce growth and response to training, and often result in weight loss and less than optimum performance.

Basic nutritional requirements for standardbreds

Energy

Energy is required to fuel the body processes and inadequate levels of energy in the diet will limit the performance of the racing standardbred. Standardbreds require almost 2½ times their resting energy intake once they commence hobble-up and regular fast work-outs after conditioning training of long slow distance exercise.

Sources of energy

Oats is typically the major energy source used in race diets. Oats is generally regarded as a “safe” grain as it has a relatively high crude fibre content and a higher starch digestibility. As an energy source, it is comparatively lower in energy and as a result many trainers also incorporate more energy dense grains such as corn and barley. A comparison of these grains is shown in the table below

Table 1. Comparison of grains typically used in racing diets.

Feed	Protein %	Best form to feed to horses	Comments
Oats	11.4	Whole or crimped	Standard and safest grain
Barley	12.8	Soaked whole, steam rolled, flaked	Palatable and well accepted – cool “conditioning” energy working horses
Corn	14.1	Crushed or cracked	Ideal energy dense boost for racing and high-performance horses in place of oats. Limit volume to avoid founder*.

* Chronic overload with high carbohydrate grain can result in low grade laminitis from excess hindgut acid build-up. This can lead to symptoms of a scratchy gait, broken-away hoof edges and foot soreness when a horse is galloped hard. Recent observations indicate that a daily supplement of FOUNDERGUARD^® - starting on half the dose and half the grain level for 2-3 days, and then increased to full grain and daily dose over 2-3 days will help to control these symptoms.

Standardbreds often continue to race until 6-7 years of age, and although older horses under heavy training may have finished growing, extra energy, protein and bone minerals must be provided to repair damaged tissues and reduce the risk of musculoskeletal breakdown as they age.

Fats & oils as an energy source

Over recent years, many standardbred trainers have used polyunsaturated oil as an energy source. The main reasons oil is added to equine diets include improvement of body condition and coat, increasing the energy component of the diet without increasing bulk and decreasing heat produced from digestion of grains. For standardbreds, during extended exercise, aerobic metabolism of fatty acids can delay blood glucose and glycogen depletion, resulting in higher muscle reserves being retained at the end of exercise and lower lactic acid accumulation. Studies also suggest that fat substituted for cereal grains can reduce gut fill and hindgut weight, which may increase speed and reduce fatigue in horses working over distances greater than 1600 m.

Horses race more consistently with a ±7-10 kg variation in bodyweight from their last winning performance. The addition of fat to the ration will also assist in maintaining body condition throughout a long race preparation.

Each oil or fat has a blend of different fatty acids (Omega-3, Omega-6) in its triglyceride content and a correct ratio of these is essential. Canola oil is generally suitable in its pure form. Oil should be added fresh each day to the meal at feed time to prevent oxidation and Vitamin E (such as Virbac’s WHITE-E^®) should be supplemented to ensure best utilisation.

Oil contains about three times as much energy as grain on a weight for weight basis. If the diet is already providing adequate energy, the amount of grain may be reduced and replaced by oil. As a general guide, one cup of vegetable oil would replace about 750 g oats.

Protein

Although the requirement of protein as a percentage of the total ration does not increase significantly with extra exercise, in hard-worked horses such as standardbreds, a ration containing 12-14% good quality crude protein is considered beneficial to maintain muscle mass, bone strength and blood counts. Usually a higher amount of protein is given in early training to promote muscle and blood development, and recent evidence suggests that in hard working horses, this level of protein should be maintained during training to help maintain muscle mass and blood counts.

Horses under stress may benefit from protein supplementation to help maintain muscle size and strength and overall race performance. Extra amounts of high quality protein, such as full fat extruded soyabean meal or cracked/crushed tick beans or crushed lupins daily during the first 6 weeks of training, and for two meals after each trial or race, will provide adequate protein for development, repair and recovery processes.

Excess protein intake must be avoided in racing standardbreds as it increases fermentation heat in the hindgut, increasing body temperature in already hard worked and heavily sweating horses, and elevates heart and respiratory rates. This leads to symptoms of thick windedness during recovery as the horses “blow off“ excess heat, which may add to the risk of blowing after exercise due to dehydration and electrolyte depletion in heavily sweating horses. As such, this can negatively impact overall speed and performance.

Fibre (roughage)

Adequate fibre as hay or chaff must be supplied to balance the high energy diet, ensure efficient hindgut digestive activity and function, and help maintain an adequate reservoir of water to combat dehydration. Feeding a proportion of 60% of concentrate and 40% roughage by weight as chaff and good quality hay (or at least one part grain to two parts volume of chaff and hay) will provide adequate fibre for these important functions, without adding excessive gut volume or weight, or risking digestive upset.

Optimum vitamin, mineral and trace mineral intake for standardbreds

The provision of specific supplements, which is possible when home-mixed feeds are made up each day, provide essential nutrients required by hard working, heavily sweating, repeatedly raced standardbreds in training to correct inadequate levels or imbalances in the diet and meet the changing needs relative to age, stage of training and stress.

Calcium

Standardbreds require adequate calcium to correct the relative deficiency in high grain or fat boosted diets, as well as replace losses due to heavy sweat output (300 mg/L) and increased bone turnover during hard training. Although 3 kg or more of lucerne hay (about 1½ biscuits) daily can provide the major part of the calcium need, a daily supplement of readily available calcium, with Vitamin D to aid its uptake, will provide a more reliable intake of calcium to meet extra requirements.

In most cases a scoopful of CAL-PLUS^® with BIOTIN for every 2 kg of concentrate fed will meet basic requirements and replace sweat loss and help maintain bone and joint strength. The added biotin will also help to maintain good, strong hooves.

Optimum vitamins and trace minerals

A well formulated and balanced quality vitamin and trace element supplement, such as FERAMO^® EVERY HORSE will provide the “foundation” source of essential nutrients for exercise, as well as supplement a basic level of iron, copper and vitamins for blood production, vitamin A to help maintain tendon strength, and B-Complex vitamins, zinc, iodine and selenium for energy utilisation and muscle strength.

A daily supplement of FERAMO^® with CHROMIUM on the other hand provides a similar wide range of vitamins and trace minerals, but also provides 5 mg chromium, a trace mineral that helps utilisation of energy and protein, and maintains muscle strength and growth during early training as a natural anabolic type effect.

Iron

Standardbreds are considered by many trainers to require extra iron in comparison to gallopers. Sweat contains 23 mg iron/L, and average sweat losses of 20 litres daily during exercise and cool down, results in a loss of 450 mg of iron. Therefore, a supplement of iron, in addition to that contained in a daily routine supplement, such as FERAMO EVERY HORSE, is recommended during extended training.

For horses with additional iron requirements, a daily supplement of IRONCYCLEN^® (400 mg iron with copper and cobalt) is recommended during training. A blood booster such as two sachets of FBC BLOODFOOD^® granules containing iron and a full range of blood vitamins and minerals can also be given for 7 – 10 days at 3-week intervals to maintain optimum bone marrow, spleen and liver stores without the need to give injectable iron which comes with a potential associated risk of reaction. A pre-race dose of 2 sachets of FBC Granules for 3 evenings prior to racing will provide extra iron and vitamins required for aerobic metabolism during competition.

Vitamin E

Vitamin E has an antioxidant function and supplementation has been shown to improve track performance in racehorses. It is recognized as a compound which dilates capillaries and preserves capillary walls. It is also known to increase cardiac efficiency significantly and reduce lactic acid production. A supplement of 1000 IU Vitamin E daily, as in pure, natural WHITE-E will provide extra muscle, blood and tissue levels of this important antioxidant to maximise muscle function, oxygen utilisation and performance. It should be noted though that vitamin E supplements should not be given together with iron or copper containing supplements in the same feed.

Optimum electrolytes intake for standardbreds

Electrolytes

Standardbreds in extended jogging work, in preparation for speed work, or those travelled regularly and raced during hot weather will require supplementary body-salt replacement to maintain water intake and replace sweat losses of up to 15-30 litres daily. Electrolyte imbalance, with loss of potassium and chloride in sweat, can lead to dehydration with “dried-out” coat, tucking up in the belly, slow recovery after exercise and reduced performance. Losses of these two salts in heavily sweating horses can also result in the development of alkalosis of the blood over time, with symptoms of spookiness, bad barrier manners and blowing hard (thick-windedness) after a hard work out. Dehydrated horses that are unable to sweat freely to cool during exercise may also pant and blow hard to offload extra heat from exercise during hot weather. A daily supplement of HUMIDIMIX^® will help to replace sweat loss.

Where horses are travelled over long distances a dose of 60 – 80 mL RECHARGE^® over the tongue with cool water provided to drink before and after travelling will help rapidly restore electrolyte and fluid levels and assist with vitality and recovery. Horses with symptoms of dehydration in the 2-3 days prior to racing can also be given 60 mL of RECHARGE over the tongue each morning and evening with access to water, and in most cases a saline drench will not be required.

What to feed standardbred horses

The table below outlines a suggested feeding program for a 450 kg Standardbred in early training and full work (racing), and based on Virbac supplements.

Feed type	Early training	Full work	Purpose in ration
BASE DIET
Oaten chaff	400g	400g	Roughage
Lucerne chaff	400g	400g	Roughage
1Whole Oats	2kg	3kg	Energy
1Steam/rolled barley	1kg	1kg	Energy
2Cracked corn		1kg	Energy
Extruded full fat soyabean meal	250g	250g	Protein
Cracked/Crushed/rolled lupins or tick beans	250 - 500g	250 - 500g	Protein
Black sunflower seeds	250g	250g	Protein/energy/fat
Vegetable Oil	1 cup	1 - 2 cups	Fat as energy
Lucerne/grassy hay	ad lib	ad lib	Roughage
SUPPLEMENT SCHEDULE
CAL-PLUS WITH BIOTIN	60g	30g	Bone & Hoof supplement
FERAMO WITH CHROMIUM	56g	56g	Trace mineral & Vitamins
HUMIDIMIX	45g	45g	Electrolytes
WHITE-E	16g	16g	Vitamin E booster
Salt (sodium chloride)	60g	60g	Electrolyte

Please note, the above feeding program is intended as a guide only. Please alter feeding rates according to individual horse bodyweight and workload. It is recommended that any new feed ingredient be added to the diet in a gradual and step-wise fashion to reduce the risk of digestive upset.

¹ The amount of barley may be increased, and oats reduced for excitable horses and for horses prone to tying up. Please note that barley is more energy dense and weighs heavier than oats. As a guideline, every 1 kg (volume 2 litres) of oats removed may be replaced by 900 g (volume 1.4 litres) of rolled barley.

² Barley may be used in place of corn for excitable horses or horses requiring additional conditioning.

Please be advised that the suggested rations are intended as a guide only. The most reliable method of obtaining nutritional information about ingredients in the diet is by analysis of samples of individual batches of feeds. The values used in these analyses are based on Australian and overseas literature. There may be some variation in the nutrient composition of feeds depending on the quality of the feedstuffs and the feed source. The information provided in this document is based on the National Research Council Nutrient Requirements of Horses (2007) publication. The actual amount of feed offered may need to be altered depending on the horse’s individual metabolism, and the quality of available roughage. If the horse in question has any health concerns, consultation with your veterinarian is advised prior to changes in feeding programs.