Electrolyte Solutions for Summer By Dr Ruth Davis BVSc
The hot summer months increase the need for body salt replacement in both racing and breeding greyhounds.  The increased level of panting needed to keep down the body temperature depletes fluid and salts from the body.  Without adequate supplementation of the important electrolytes potassium, sodium, chloride and magnesium, problems such as dehydration, loss of performance and muscle cramping may occur.    Greyhounds are typically poor drinkers and may only consume 500-750 mL of water per day.  Another 1 litre of fluid may be obtained from meat, vegetables and moistened dry food.  Greyhounds can however, lose over 200 mL of fluid per hour when panting.  Therefore any factor that causes prolonged panting can lead to dehydration.   Heat, excitement, nervousness, prolonged walking, traveling and racing can all cause dehydration in greyhounds.   PROBLEMS ASSOCIATED WITH ELECTROLYTE DEFICIENCIES or IMBALANCES Chronic dehydration Muscle cramping Loss of performance Nervousness Dehydration Dehydration is one of the most common problems found in racing greyhounds particularly during the summer.   Clinical signs are usually easy to recognise and include a dull, dried out coat, a slow "skin pinch" return over the neck and shoulders, a tucked up belly and passage of small volumes of concentrated urine. Dehydration can be due to loss of body fluid only, or to the loss of both fluid and body salts.  The first type is known as simple dehydration where only the fluid content of the body is depleted.  This may be due to shallow panting after exercise or traveling or to lack of drinking water.  As the fluid content of the blood decreases, the body salt concentration is increased, which stimulates the thirst response, leading to drinking if water is available and replacement of the lost fluid. The second, more serious type of dehydration is known as chronic dehydration.   In this form of dehydration both fluid and body salts are depleted, preventing the thirst response from being triggered.  If electrolyte supplements are not given the greyhound is unlikely to drink sufficient water to correct its dehydration.  This form of dehydration is most common in excitable, hard walking greyhounds that pant more forcibly than normal.   It is theorized that this results in higher amounts of water loss from the lungs and an increased loss of salts, particularly potassium, from the kidneys.  Chronically dehydrated greyhounds often suffer from a loss of racing performance, poor recovery after racing and an increased risk of cramping. Tips to Avoid Dehydration during Summer Provide a constant supply of fresh clean drinking water.  Use a heavy bowl that can't be tipped over and place the bowl in a shady area of the kennel.  Greyhounds are likely to drink more water if it is kept cool.   Some dogs will drink better if the water is flavoured with honey, Vegemite or stock cubes.   Provided a daily electrolyte supplement such as BETACEL that is designed specifically for greyhounds.  A 3 g dose of BETACEL should be given to both racing greyhounds and brood bitches. This dose can be doubled to 6 g per day, split between the morning and evening meals, in very hot weather.  In addition to providing potassium, chloride, sodium, magnesium and citrate and lactate salts acid buffering salts, BETACEL will switch on the thirst response and encourage the greyhound to drink. It is very important not to use electrolyte supplements designed for humans or horses as these products are usually too high in sodium and too low in potassium for greyhounds.   Remember that greyhounds pant to cool their bodies, while horses and humans sweat.   These two different cooling mechanisms lead to completely different levels of electrolyte loss.  Too much sodium can be detrimental to a greyhound's health and performance. Extra potassium in the form of BETA-K tablets should be provided to greyhounds prone to dehydration.  All greyhounds that are "hard walkers", barkers or are prone to muscle cramping will benefit from this potassium "boost".  BETA-K is a specially coated slow release tablet that ensures a constant supply of potassium to the greyhound.  Always give the tablet over the tongue and ensure that the dog swallows it whole, as chewing will destroy the slow release coating. Give one BETA-K tablet over the tongue just prior to the morning meal during hot weather.  Nervy, barking greyhounds may require extra potassium all year round to prevent chronic dehydration. It is also advantageous during hot weather to give 2 BETA-K tablets over the tongue 4-6 hours before the race start time. Moisten dry food or biscuits for 15 minutes prior to feeding with water, milk, meaty broth or vegetable cooking water to a mushy but not sloppy consistency.   Adding extra fat to the diet provides extra "metabolic" water that is released as the fat is digested.  Two tablespoons (30-50g) of fat can be added to lean meat diets to increase the fat content during summer.    Provide well-ventilated kennels during hot weather.  High, ventilated, gabled roofs are better than low flat sheds.  Locating kennels in shady areas and the use of light coloured reflective paint help to keep the interiors cool.   Provide a rapid rehydration fluid such as RECHARGE after trialling, racing or travelling.  RECHARGE is the greyhound equivalent of a "sports drink" and is designed to quickly replace the fluids and electrolytes lost during exercise or traveling, without having to wait for the dog to consume a full meal.  When traveling to race give 2 teaspoons of Recharge in a cup of cool water prior to kenneling at the track, and again after racing.    Once the greyhound is fit, reduce the amount of walking to ½ - 1 kilometre per day, as prolonged walking can lead to chronic dehydration particularly if the greyhound is a hard walker.   A combination of, electrolyte supplementation, feeding modifications, good management and common sense will help to avoid dehydration and maintain performance in your greyhounds, even during the hotter months.