Mechanism of action of drinking water acidifier
1. Reduce the pH value of drinking water, inhibit harmful bacteria, and purify water quality
In large-scale farms, there are a large number of microorganisms such as Escherichia coli, Salmonella, mold and fungi in closed water towers, drinking water lines and drinking water with poor water sources, which pose a huge threat to the health of poultry. Most harmful bacteria are suitable for growth in a neutral to alkaline pH value, such as Escherichia coli 6.0-8.0, Salmonella 6.0-7.5, Staphylococcus aureus 6.8-7.5, Streptococcus 6.0-7.5, Clostridium 6.0-7.5, Clostridium perfringens 7.2-7.5. When the pH value is less than 4.0, a large number of harmful bacteria will be inactivated.
Adding drinking water acidifiers can reduce the pH of drinking water and effectively inhibit the reproduction of harmful bacteria through a dual mechanism of action: ① Fumaric acid, citric acid, etc. can indirectly inhibit bacterial growth by reducing the pH value of the intercellular matrix of pathogens and destroying the osmotic pressure system of pathogens; ② Formic acid, acetic acid, propionic acid, butyric acid, etc. can reduce the pH value of the environment while the undissociated molecules penetrate the cell wall of G- bacteria through passive diffusion and active transport mechanisms to enter the cell, dissociate H+ and RCOO- in the relatively alkaline environment of the cell, and inhibit the metabolism of certain macromolecules such as DNA, RNA, protein or lipids, cell membrane components, etc. by reducing the intracellular pH value, thereby achieving the effect of sterilization and purification of water quality. Ren Fangkui et al. found that drinking water acidifiers (mainly formic acid + ammonium formate) can significantly reduce the pH value of water, and when added at a rate of 0.2%, it can significantly inhibit the growth and reproduction of pathogenic microorganisms in the water line such as Escherichia coli.
2. Reduce gastrointestinal pH, increase digestive enzyme activity, and promote digestion and absorption of nutrients
The optimal pH of pepsin is 2.0-3.5. When the pH exceeds 3.5, the activity is significantly reduced. When the pH exceeds 6.0, pepsin is inactivated. When the acidifier enters the gastrointestinal tract of poultry, H+ and RCOO- will be released immediately. The dissociated H+ will reduce the pH value of the gastrointestinal tract, thereby increasing the activity of pepsin, improving the utilization rate of protein and feed. Organic acids can also convert inactive pepsin into active pepsin and stimulate the duodenum to secrete trypsin, further promoting the digestion and absorption of protein. Xiao Qin et al.’s research shows that a composite acidifier containing phosphoric acid, fumaric acid and formic acid can significantly reduce the pH of the crop, duodenum, jejunum and ileum of broilers at 42 days of age, and the pH in the digestive tract is linearly related to the addition level of the acidifier.
In addition, an acidic environment can promote the body’s absorption and utilization of minerals. Most minerals are easily soluble in acid, and organic acid anions can complex with elements such as calcium, phosphorus, magnesium, and zinc to promote the digestion of minerals and reduce the excretion of minerals and nitrogen and phosphorus, thereby reducing environmental pollution. Kirchegessner et al. found that fumaric acid can improve the apparent absorption and deposition of calcium, phosphorus, and zinc. Acidic environments can also promote the activity of enzyme preparations. At the same time, organic acids can delay the time of digestion and emptying, providing more reaction time for enzymes and substrates. For example, organic acids and phytase show synergistic effects, thereby improving the utilization rate of mineral elements by livestock and poultry.
3. Inhibit the growth of harmful bacteria and improve intestinal microbial flora
The number and distribution of beneficial and harmful bacteria in the digestive tract will directly affect the digestion and absorption of nutrients by livestock and poultry, and have a significant direct impact on the growth of livestock and poultry. When harmful bacteria dominate the digestive tract, they will inhibit the growth of animals, and vice versa, they will promote the growth of animals. The main beneficial bacteria in the intestines of poultry are bifidobacteria and lactobacilli, and the main harmful bacteria are Escherichia coli, Salmonella and Staphylococcus aureus. Previous studies have shown that formic acid in acidifiers can inhibit the growth of Salmonella, and malic acid or citric acid can inhibit the growth of Escherichia coli. Dong Wenwen et al.’s research shows that drinking water acidifiers can inhibit the growth of Escherichia coli and Salmonella and promote the production performance of laying hens. Guo Yujun et al.’s research shows that drinking water acidifiers can reduce the acidity of drinking water and inhibit the growth of Escherichia coli, Salmonella and Staphylococcus aureus, thereby improving the microbial flora of broiler intestines. Research by He Jikai and others shows that adding 0.1% liquid organic acid to drinking water can improve intestinal health by regulating the intestinal microbial flora of laying hens, promote the proliferation of beneficial bacteria, and thus reduce pathogenic diarrhea in laying hens.
4. Improve the anti-stress ability of poultry and improve the body’s immunity
The immune system is the most important disease defense barrier for poultry and plays a key role in the healthy breeding of poultry. Acidifiers reduce a series of stress reactions caused by environmental changes by regulating the body’s acid-base balance. When the body is under stress, fumaric acid, citric acid, etc. participate in the rapid synthesis of ATP in the tricarboxylic acid cycle, provide energy for poultry under stress, improve the body’s ability to resist external stress, and thus improve the body’s immunity. The research results of Zhu Tao et al. show that butyrate can be directly absorbed by the small intestine, provide energy for rapid cell differentiation, promote intestinal epithelial cell renewal, and stimulate the repair of intestinal villi. Previous studies have shown that organic acids can increase the weight of lymphatic organs and spleen weight, increase the immune organ index of yellow-feathered broilers, reduce intestinal inflammation of broilers, and improve the immunity of broilers. Organic acids such as lactic acid and butyric acid can also synthesize glucose through pathways such as gluconeogenesis, thereby ensuring the normal nutrient supply and material metabolism of poultry, and indirectly affecting the normal operation of the immune system. Guo Yujun’s research shows that adding compound acidifiers to drinking water can reduce the levels of pro-inflammatory factors in the intestines and serum, reduce inflammation in the body, and thus improve the immune function of broilers.
