Avian Nutrition: Electrolytes

[Snowbird]

OVERVIEW:

The concentration and balance of electrolytes in a bird’s intracellular and extracellular fluids are critical for life and are therefore tightly regulated. Among the dietary minerals, sodium and potassium are the positively charged and chloride is the negatively charged electrolyte minerals. A bird’s dietary requirement for these minerals must be considered in two ways: the minimum amount of each needed for each cellular function and the balance between different electrolytes necessary to optimize important osmotic (diffusion of water through cell membranes), and acid-base relationships.

FUNCTIONS:

There are systems and chemicals which enable secretion, absorption and the coordination of the net levels of electrolytes in the body. All three of these minerals are extremely important to maintaining ionic balance in body fluids. Sodium is the predominant extracellular cation (+) and functions to maintain plasma volume and osmolarity (the concentration of the osmotic solution), potassium the predominant intracellular cation that performs the same function. The potential energy resulting from the separation of these two cations—a kind of tension between them across the cell membrane—drives nerve impulses and other forms of cellular communication. Chloride (-) plays a similar role in the extracellular environment. Concentration of Chloride anions results in Hydrochloric acid in the stomach—a major aid to gastric digestion. All of these minerals also function as regulatory and cofactor roles with a wide variety of enzymes. They also function as active cotransports of many nutrients and waste products across cell membranes and provide osmotic drive for water movement.

DIETARY ELECTROLYTE BALANCE:

Maintenance of constant internal pH is critical to the function of all physiological processes and the structural integrity of macromolecules. When dietary organic acids and bases metabolize, they contribute to states of alkalosis and acidosis. Dietary electrolyte balance is usually expressed as Na+, K+, CL- since most organic acids and bases are associated them.

The appropriate electrolyte balance is dependent on the physiological state of the bird and the species. The physiological state is important, because processes such as bone formation, eggshell deposition, ketosis, lactic acidosis, and respiratory rate affect the bird’s acid—base balance. For example it is known that racing pigeons are more efficient with thermoregulation in a more acidic condition.

The acid—base balance of chickens has been extensively studied (and pigeons and other grain eaters) and the range for optimal growth is well known. Outside of this optimum range poor bone mineralization and a variety of anomalies with the legs and joints occur as well as well as thin egg shells. In hot weather, a panting bird is exhaling CO2 and this loss causes an alkalosis condition that is corrected with acidified diets as well as water. Different classes of birds have wide variation in optimum acid—base range.

REQUIREMENT:

Grain eaters require between 0.1% and 0.2% of dry dietary matter during growth and egg production. The maintenance requirement is about 0.05%. Na and Cl should be about 1:1 ratio by weight, although dietary potassium modifies the ideal ratio by affecting the overall electrolyte balance. High levels of Na or K increase the Cl requirement and conversely high dietary Cl increases the Na/K need.

DEFICIENCIES:

There is a sizable reserve pool of these minerals in bone. But this pool is mobilized in a fasting condition and not so readily in a deficient diet condition. Chloride deficiency causes poor egg production, dehydration, and a bird that is easily stressed by noise. The primary signs of insufficient dietary potassium are reduced appetite, muscle weakness, respiratory distress, and cardiac weakness. A sodium deficiency causes decreased plasma fluid volume, low blood pressure, decreased bone strength, poor growth, and a reduction in reproductive capacity.

It has been proven that birds have a specific appetite for sodium chloride. When deficient, they develop a craving and actually seek out salt sources. All species that have been examined can easily choose between diets identical in all aspects except sodium chloride concentration in order to meet their requirements and avoid excesses. When a choice is not given, birds typically do not increase their consumption of low-salt foods in order to obtain their electrolyte requirement—they do not over consume metabolizable energy in order to meet their requirement for sodium or chloride.

Regurgitating parent birds need extra electrolytes and diarrhea and other gastrointestinal disturbances increase the secretion and decrease the absorption of electrolytes, markedly increasing the requirement—electrolyte replacement therapy is a common component of the veterinary care given birds suffering from intestinal infections.

If an aviary bird (without access to outside foraging) is not given dietary salt, there will be a deficiency condition with consequences to long term health. Platt (1951) raised White King Pigeons on yellow corn (35%), milo (25%), wheat (20%) and green peas (20%) over a period of 18 months and supplemented the grain with several mineral mixtures. Oyster shell alone was insufficient, but a mixture of oyster shell (85%), ash (10%), and sodium chloride (5%) compared very well with all the more complex supplementation when various parameters of squab production were used as a criteria of adequacy (size, rate and extent of weight gain, health, perhaps other parameters). It may be a factor that pigeons drink water up to and well over 10% of their body weight per day, which may result in a higher rate of salt excretion.

Salt may be offered on the side and the birds observed.

TOXICITY:

Even birds without salt glands have a high tolerance for salt if fresh water is available. Pheasants and quail can tolerate a 5% salt diet if water is available.


Note about kinds of salt: If the salt you use is very white and flows nicely, then it is probably bleached, kiln dried, heated over 1000 degrees, or altered with chemicals or pollutants. These salts have little or no trace elements. There are salts from the sea and salts mined from unpolluted ancient deposits in Utah that are cheap and contain natural and unpolluted trace minerals of calcium, potassium, sulphur, magnesium, iron, phosphorus, iodine, manganese, copper, and zinc. Many think the taste is better as well.

[Trees Gray]

Snowbird, I hope you are keeping all this information for quick reference.

Once again, the closest to nature the ingredients are, the better balanced and utilized through the blood vessels and the tissue. The artifical coloring and flavorings in products like Gatorade make it a poor choice for rehydrating.

Too few products are actually tested to see if they help in stamina and performance. A good rehydration product should keep blood levels constant and not drained while excercising.

Treesa

[Christina Coughlin]

My vet suggested the use of plain, clear pedialite for use on sick, recently caught, or over heated birds from parrots to pigeons and even chickens. I have used it now for about 5 years and have always had great results. I mix it in baby food and will use it in place of water depending on the situation. I have never had a bird refuse to drink it, not even the most picky. My vet is really into natural remedies with the birds so I know this is probably the safest method right now for me to use (since I can use it on anyone), the added bonus being that I can get it anywhere in an emergency even the gas station has it!