Harm of Ammonia to Livestock and Poultry Farming and Countermeasures (Part II)

Table 2 The Impact of Ammonia Concentration on Certain Production Performance and Respiratory Disease Incidence in Pigs (Cao Jin, 2003 )

Note: 1. Different lowercase letters in the same row indicate significant differences. P<0.05 )

    2. Production performance-to-price ratio ={ Control group pig length 1KG Required feed cost (yuan) ÷ Pig weight gain in the experimental group 1KG Required feed cost (yuan) + Treatment cost (yuan) } × 100 %

2.1.3 Affect the immune efficacy of vaccines

In livestock and poultry houses with poor ventilation and inadequate management, when the concentration of ammonia in the air is too high and the exposure duration is prolonged, it can damage the cilia. — The function of the mucosal structure leads to respiratory infections and associated inflammation. More seriously, it will impair the ability of respiratory-associated lymphoid tissues to respond to antigens.

Song Yi [8] ( 2009 ) and others found through experiments that low-concentration ammonia gas (ammonia concentration < 40mg/kg ) Exposure does not affect the immune response to the attenuated Newcastle disease vaccine, whereas high concentrations of ammonia ( 50-80mg/kg ) Exposure significantly reduces the increase in antibody titers following immunization with a live attenuated Newcastle disease vaccine. Furthermore, it was found that broiler chickens exposed to high concentrations of ammonia... 6 One week later, the increase in antibody titers following immunization with the attenuated Newcastle disease vaccine was significantly lower in the experimental group than in the control group and the low-concentration ammonia group. These experimental results indicate that broiler chickens exposed to ammonia concentrations exceeding... 50mg/kg In this environment, the immune efficacy of the attenuated Newcastle disease vaccine is significantly reduced, and broilers become more susceptible to Newcastle disease. Meanwhile, this experiment also found that exposure to a high-concentration ammonia environment leads to changes in serum lysozyme levels and... NK Cell cytotoxic activity is reduced.

3. Measures to Reduce Ammonia Emissions

3 . 1 Select sites scientifically and rationally, and strengthen daily management of livestock and poultry.

Livestock and poultry farms should be located in areas that are elevated, dry, have open terrain, convenient drainage, and good ventilation—areas that are free from nearby residential zones, chemical plants, slaughterhouses, and mining areas, which tend to generate significant pollution. The design of pig houses should be rational, ensuring the thorough and timely removal of waste materials such as manure, bedding, and wastewater, thereby minimizing the generation of harmful gases inside the sheds. Daily management should be strengthened: manure, urine, and wastewater must be promptly and thoroughly cleaned out of livestock and poultry houses to maintain cleanliness. Additionally, the drinking water system should be comprehensively inspected, flushed, and disinfected regularly to ensure smooth water flow, eliminate dripping or leaking, and keep the area dry. It is also crucial to maintain an appropriate stocking density; excessively high stocking densities can easily lead to a dramatic increase in ammonia production as temperatures rise, posing serious health risks to animals. Therefore, proper ventilation and air exchange are particularly important, enabling the timely and complete removal of harmful gases generated inside the sheds. Generally, ventilation and air exchange should be carried out at noon on clear days when temperatures are relatively high.  
3.2 Optimize feed formulations to reduce ammonia emissions.  

Diets formulated according to the “ideal protein pattern”—that is, diets in which amino acid levels are optimized to match the animal’s requirements—can improve digestibility, particularly enhancing the utilization of dietary protein and amino acids and reducing ammonia emissions within the barn. Canh T T [9] (1998) According to the report, for every decrease in the crude protein level of the diet calculated using an ideal model, 1 %, the release of ammonia from feces and urine decreases. 10 %~ 12.5 %. By employing amino acid balance nutrition technology and appropriately adding synthetic amino acids to the basal diet while reducing the crude protein level accordingly, we can both conserve protein feed resources and decrease nitrogen excretion in livestock and poultry manure. Aarnink [10] Wait ( 1995 ) The experiment showed that when the crude protein content per kilogram of diet is reduced, 10g At that time, the ammonia nitrogen in the excreta decreased accordingly. 9 %. Stutton [11] Wait ( 1998 ) The study found that the crude protein level in the diet ranged from 18 % to decrease 10 %, then add synthetic amino acids, and the ammonia nitrogen and total nitrogen in the excreta will decrease accordingly. 40 % and 42 %.   Acids and phenolic byproducts from tyrosine degradation pose serious threats to the health of both humans and animals. Hobbs et al (1996) By adding synthetic amino acids to the diet, the protein levels in the diets for growing pigs and finishing pigs were adjusted from... 21 % to decrease 14 %, from 19 % to decrease 13 %, resulting in a reduction in urinary nitrogen excretion. 40 % (P<0 . 01) It also significantly reduced the odorous substances in both feces and urine.

3.3 Reduce ammonia emissions by adding feed additives.

3.3.1 Adding probiotics reduces ammonia emissions.

Probiotic preparations help enhance the body's metabolic functions, improve feed utilization, and boost production performance. They also reduce livestock and poultry excreta, yielding significant economic, social, and ecological benefits. Bacillus species produce aminoxidase and enzymes that decompose hydrogen sulfide in the large intestine, enabling them to completely oxidize odorous indole compounds into substances that are odorless, non-toxic, and environmentally friendly. Meanwhile, Bacillus strains possess enzymes capable of utilizing ammonia, thereby helping to lower blood ammonia levels. An Yongyi [12] ( 1997 ) Studies have found that feeding live microbial preparations dominated by yeast or Bacillus can significantly reduce ammonia production. The former can assimilate uric acid, inhibit the production of ammoniacal nitrogen, and increase protein nitrogen; the latter can reduce amino acid deamination in the intestine or enhance the intestine’s capacity to bind ammonia. Liao Xindi [13] ( 2002 ) Studies have shown: Adding [substance] to the normal diet of growing pigs... 0.05 % live bacterial agent; continuous use of the live bacterial agent 10 After the treatment, the ammonia levels in the two pens were reduced respectively. 40.28 % and 56.46 %, total nitrogen and ammonia nitrogen in urine decreased. 25 % and 38 %. Zhang Xilei [14] ( 2006 ) The trial showed that adding [something] per ton of complete feed... 50g Feeding broilers with Bacillus licheniformis not only reduces ammonia emissions inside the poultry house but also improves the growth performance of broilers. Bu Changying [15] ( 2008 ) Added to the experimental feed 0.1% 、 0.3% 、 0.5% All three levels of Bacillus strains can enhance the utilization of dietary protein by broiler chickens and significantly reduce... 14 Age in days and 28 Urease activity in the excreta of day-old broilers and the emission of ammonia from their excreta. Zhang Liping [16] ( 2010 ) Added separately to broiler diets 0、0.5、 l 、3、 5 g/kg enzyme preparations ( The main ingredients include Bacillus licheniformis, Enterococcus faecalis, Lactobacillus acidophilus, and others. ) The study examined the effects of enzyme preparations on the total airborne bacterial count in broiler houses and the ammonia concentration in fermented manure. The experimental results showed that, compared to the control group, adding [enzyme preparation] to the diet... 3g / kilogram The enzyme preparation can significantly reduce the microbial content in the air and decrease the ammonia concentration. (P<0.05) 。 

3.3.2  Add enzyme preparations or acid preparations to enhance nitrogen utilization.  
　　The addition of enzyme preparations and acid preparations to enhance nutrient digestibility has been widely demonstrated. There are many types of feed enzymes available; generally, they can be categorized into two major groups: digestive enzymes and non-digestive enzymes. Digestive enzymes have substrates and mechanisms of action similar to those of the digestive enzymes normally secreted by the animal’s gastrointestinal tract. They primarily include amylase, protease, and lipase. Non-digestive enzyme preparations mainly include phytase, cellulase, and xylanase. Beta- Dextranase, pectinase, and others. In production, these enzyme preparations are typically used in a selective combination based on the characteristics of the diet. Zhang Keying [17] Wait ( 2001 ) Research indicates that adding [something] to piglet feed... 500  Unit / Kilogram of phytase can significantly improve the production performance of piglets, increase the ileal digestibility of tryptophan, and enhance the utilization of phosphorus and protein.

3.3.3 Add non-starch polysaccharides ( NSP ) Reduce ammonia emissions 　

The study found that increasing non-starch polysaccharides in the diet... (NSP) The content can reduce urinary nitrogen excretion and increase fecal nitrogen excretion. Since the rate at which urinary nitrogen is converted into ammonia is significantly higher than that of fecal nitrogen, increasing the level of non-starch polysaccharides in the diet will help reduce both the production and emission of ammonia. Cruiser Wait ( 1993 ) Research indicates that adding [something] to pig feed... 10%-22% non-starch polysaccharides ( NSP ), which can reduce urinary nitrogen excretion. 35%-39% Increased fecal nitrogen 20%-80% [18] When non-starch polysaccharides in feed... NSP ) Content from 14% Increase to 31% At that time, the ratio of urinary nitrogen to fecal nitrogen was from 3.8 Reduce to 1.2 [19] 。

3.3.4  Add a chemical deodorizer to reduce ammonia emissions.
　　Currently, among the additives that show relatively good deodorizing effects are silicate-based materials such as zeolites and bentonite. Zeolites adsorb gas molecules and water molecules through their three-dimensional porous channels on the surface, thereby reducing the production of ammonia and other harmful gases in livestock buildings. At the same time, they can also lower the humidity of air and manure within the building, achieving the goal of odor control. Shi Qinghe added bentonite to feed, which helps bind ammonia in feces and urine, thus reducing the emission of ammonia. Meanwhile, some researchers have also explored adding [something] to animal feed. 120 mg/kg The deodorizing agent significantly reduced the results in the experimental phase. 5 ~ 7 The concentration of ammonia in the pigsty increased the pigs' daily weight gain. 9.4 %.  
3.3.5  Adding plant extracts reduces ammonia emissions.
　　Plant extracts have garnered widespread attention for their ability to eliminate odorous compounds accumulated in the gastrointestinal tract, thereby effectively reducing unpleasant odors. The ammonia- and odor-control premix feed developed by Wen Lixin et al. can significantly reduce the production of harmful gases such as ammonia and hydrogen sulfide within pig houses. When added to pig feed, it... 65 g/T Yucca extract, for animal feeding 600 Piglets and growing pigs 60 d The ammonia emissions from the pigsty have been reduced. 26 %. In crude protein content 16 % and 14 When yucca extract is added to 10% of the pig feed, the volatilization of ammonia in pig houses is reduced accordingly. 48.8 %, 33.50 %.
3.3 .6  Other methods to reduce ammonia emissions  
　　Treating manure and bedding with certain chemical substances is highly effective in reducing ammonia levels. These substances can absorb ammonia from both manure and bedding; for example, hydrogen peroxide, potassium permanganate, copper sulfate, benzoic acid, and acetic acid all have odor-inhibiting effects. Use... 4 % copper sulfate or 2 Using benzoic acid to treat bedding material can effectively control or reduce ammonia concentrations.
4  Summary and Outlook  
　　With the rapid development of the livestock and poultry breeding industry, harmful gases in livestock and poultry houses... —— It has become a well-recognized fact that ammonia seriously affects the health and production performance of animals. Moreover, the issue of ammonia-induced environmental pollution around livestock barns is becoming increasingly prominent. Therefore, how to achieve coordinated development between animal husbandry and the environment has emerged as a key concern for people. Air quality is closely linked to the health of livestock and poultry, as well as to human health. Thus, it is essential to adopt effective measures to reduce emissions of harmful gases such as ammonia. By applying the concept of healthy ecological farming—taking into account comprehensive factors including environmental control, daily management practices, feed formulation, and regulation of metabolic processes within the body—we can control ammonia generation at its source, thereby reducing disease incidence, enabling producers to reap greater economic benefits, and ensuring better protection of our living environment.