So that the body could serve power, it needs energy. And here it is again, when nature shows its excellence. What is the motoring enthusiasts waited until recently - the hybrid drive their cars, it works in the animal body completely, of course. Automobile hybrid engine is such machine that uses electric power from the battery during the start-ups and low speeds, and it switches to the combustion engine at higher speeds and at greater distances. This reduces overall energy consumption.
And how does it work in the body? The muscle fibres are the special engine there are numerous energy sources. Initially, at the beginning of the the performance such substances are utilized, which are located within the muscle - adenosine triphosphate (ATP) and creatine phosphate. They are available immediately, but very soon exhausted. At maximum load it lasts only a few seconds. Then comes the sugars - glucose and glycogen. Glycogen is composed of many glucose units and thus constitutes the reservoir in the body. A cleavage (combustion) of glucose releases energy (ATP). This way the body functions eg. in racing greyhounds. The dog is capable of a maximum speed of 60 km / h, but keeps it only for about 30-40 seconds. Everything takes place without the use of oxygen in glucose and in that case the lactic acid is formed and accumulates in the muscles. When the amount exceeds a certain threshold, dog is feeling tired, its muscles are burning and hardening and the dog must then slow down or even stop. In contrast to just-described anaerobic sprinting load there is another extreme endurance load which is typical for sledge dogs. Deploying in this case is not maximal, but it takes a very long time. The beginning of "production" power is the same, but glucose is cleaved in the presence of oxygen and thus lactic acid does not accumulate in the muscles. Glycogen stores in the body are also limited, and after a few minutes, the body begins to use the latest energy source - fat, respectively fatty acids from which the fats are assembled. Fatty acids are gradually becoming a vital source of energy and according to length of the burden involved in the production of energy from 70-90%. The body still retains a certain amount of glycogen in the muscles that are used during sudden load increase - eg. steep climb or final finish.
So far we have not mentioned proteins. That's because they are the least desirable source of energy and the body is used only in an emergency when it does not have enough sugar and fat. Proteins can not be stored in the body into stock, their conversion to energy is inefficient and produces the ammonia. Ammonia acts as a poison in the body and therefore must be quickly converted and taken from the body in urine. This does not mean that the body would not need protein, i tis just the opposite. When training is to increase muscle mass and to gradual physiological changes that ensure better supply of oxygen and nutrients to the working muscles. The amount of blood and red blood cells increases, the density of the network of capillaries, the volume of mitochondria (this is actually a cellular "power"), and the activity and amount of digestive enzymes. It follows that increasing the repeated load (training and races) growing need for protein. It is important to provide a dog just that amount of protein which is necessary for growth and tissue repair. Their abundance, but also reduces power shortage.
In the introduction I mentioned the need of energy for muscles. It was the energy from internal resources and the need to supplement feed. The total daily energy consumption depends on the weight, intensity and duration of the load and on the conditions of the environment in which the dog moves. A typical sled dog in the summer is usually kept in shape only in the form of light training, and needs about 800 calories a day. Challenging season race training, long-distance races and freezing temperatures may mean that the same dog will need up to 10,000 calories a day. Only a properly chosen feed will give him a boost of energy. The primary requirement is a high digestibility of raw materials used and balance of nutrients due to its energy content. The dog must obtain the necessary energy in an amount of feed that is actually able to eat and digest. An ideal energy source, in this case fat – will provide it in concentrated form and contribute significantly to overall palatability ration.
Also water demand increases according to the degree and duration of activity, and depending on the ambient temperature.. The normal daily consumption of water is 35 to 50 ml per kilogram body weight, but Sustained load increases three to fivefold. It is caused by increased production of urine because the kidneys must dissipate greater amount of products created during metabolism from the body. During long races the water should be replenished regularly to avoid dehydration. The dog is then not able to maintain their body temperature and performance strongly decreases because more heat must be dissipated by the body surface, which is at the expense of blood flow in strained muscles. It is appropriate to supplement and electrolytes with water, especially sodium, which urine leaves the body.
The literature indicates that a properly designed food for sledge dogs in times of high load should contain more than 4500 kilocalories of metabolizable energy per kilogram, and the following ratio of energy sources: 53% of energy from fat, 32% of energy from protein and 15% of the energy of carbohydrates. The daily ration should be divided into several parts. The dog gets the largest portion of the feed after the work done so had plenty of time to digest. It is suitable to supply dog with water during breaks in the performance, may also be used with During breaks in the performance, it is appropriate to supply the dog, snacks with a high fat and protein may also be. It is good to receive products or food containing L-carnitine during initial and racing season. It is involved in the transport and conversion of fatty acids into energy and can significantly contribute to delaying the onset of muscle fatigue and speed up recovery after exercise. Also supplement of chondroitin and glucosamine can be recommended – it contains nutrients needed to restore the articular cartilage.
Although the type of load racing dogs is significantly different from the load sled dogs, they also feed energy should be concentrated and easy to digest that food intake may not be too high. Energy from fat should be at 42% from protein and 31% from carbohydrates 27%. In both types of loads can also be successfully used method received from human athletes, where the animal immediately after the load feed or drink rich in easily digestible carbohydrates. The body stores of glycogen in the muscles more than usual. This dietary manipulations can increase endurance and strength, which is the quantity in the muscles directly dependent.
Supply of fresh water and a balanced diet is an essential condition for achieving adequate performance. For working and sporting dogs used with any nutritional deficiencies occur much faster and stronger than the dogs in the load current increases the susceptibility of animals to injury hinders and restricts its performance and shortens the active age of his life.
On behalf of Nativia team
Ing. Jan Jirásek
