The bioactivity of active compounds is often reduced when exposed to air, moisture, or heat. Pet food loses 30% to 50% of vitamins during processing. Similarly, poultry feeding enzymes become unstable and lose potency when subjected to air, high temperatures, humidity, and steam during the pelleting process. The activity of phytase enzymes, used for better phosphorus absorption in poultry and pigs, is significantly reduced during hot summer months. Probiotic bacteria are also fragile requiring storage in dry conditions. Vitamin C is unstable, and prolonged storage of animal feed enriched with vitamin C leads to losing health benefits.
Low stability and interactions
Many oils go quickly rancid, such as omega-3 fatty acids, commonly used as a supplement for animals. The minerals encounter interaction reactions as they pass through the gastrointestinal tract. Elevated levels of molybdenum, selenium, iron and sulphur interfere with copper absorption, and copper deficiency is a severe problem for cows, sheep, and goats.
Drugs and supplements often face mixing challenges. In warm weather, minerals may turn into hard pellets making it difficult to combine them with feed ingredients.
Delivery challenge due to taste and odour
The delivery of drugs and supplements is a common challenge due to the taste, odour or texture. The pills, the most common form of medication and supplements, are often disguised with chicken, beef, or fish flavours. But even this does not guarantee success. In addition, the pills usually have a low absorption rate and cause stomach irritation. Using baked snacks and kibbles as a disguise has shortcomings as high temperature destroys heat-sensitive compounds, such as probiotics, enzymes and flavonoids. Soft-moist treats are an alternative, but moisture and acidity negate their viability.
To solve the problem of drug administration, companies offer “pill guns”, but it is not the ideal solution. Crushing pills into a powder can reduce the effectiveness of certain drugs. Drugs in liquid form have better absorption and cause minor stomach irritation, but the taste may be a concern. A similar taste issue is encountered with drugs in a powdered form. Sick animals, who eat less, may not receive the optimal drug dosage.
Today, medications may come as injections or implants that slowly release in the body or as aerosols and transdermal patches that deliver drugs through the skin to the bloodstream. However, not all can be suitable. Also, the drugs can be deposited on the fur, ingested by the animal, and cause airway irritation.
Delivery challenge due to pH
Medicated feeds, such as antibiotics, used to increase growth and protect from pathogens have recently come under scrutiny due to the development of antibiotic resistance in humans. The trend shifts from the emphasis on productivity to safety, and the manufacturers turn towards probiotics and enzymes, known to promote gut health, thereby lessening the use of antibiotics. But probiotics are affected by packaging and storage conditions, as well as by pH. The challenge is to get the living microorganisms to survive the stomach’s acidic environment to reach the intestines.
There are many supplements and drugs sensitive to the acidic environments of the stomach, for example, L-arginine (used to repair animals’ wounds or fractures), feed proteins and lysine hydrochloride (to increase milk production in lactating dairy cows). The challenge is to pass through the gastrointestinal tract to reach the hindgut of monogastric animals.