Application of Allicin as a Feed Additive
Allicin is the collective term for the main bioactive components in garlic. In China, allicin has a long history of use as a medicine. It is a broad-spectrum antibacterial agent with multiple biological functions such as anti-inflammatory, blood pressure-lowering, blood lipid-lowering, platelet aggregation-inhibiting, anti-cancer and anti-viral effects. Its use as a feed additive in livestock and aquaculture was developed through research and exploitation based on the development of rural farming, and it has promotional value. The author now introduces the application techniques as follows for readers' reference.
(I) Functional effects of allicin
1. Bactericidal action. Allicin has good inhibitory and killing effects on Escherichia coli, Salmonella, Pseudomonas aeruginosa and other bacteria that cause diseases in livestock and aquatic animals. It is particularly effective against enteritis in dairy cows and meat pigs, gill rot disease, red skin disease in grass carp, and explosive infectious diseases in fish. It is currently an effective approach for disease prevention and control in rural areas to save investment in developing the farming industry.
2. Improving feed palatability. In recent years, many farmers, in order to reduce feed costs, often use feed ingredients with poor palatability or add some growth-promoting drugs in compound feed, causing decreased feed intake or refusal to eat in farmed animals, resulting in slow growth and emaciation. Adding allicin can significantly improve feed palatability and increase feed intake.
Allicin attracts animals to consume feed through the smell of garlic, stimulating their appetite and thereby increasing feed intake. The vast majority of animals, especially fish, greatly favor the smell of allicin.
3. Improving production performance. Allicin can not only increase animal feed intake, but also prevent and treat multiple diseases, improve immune function, improve the functions of various system tissues in the animal body, promote gastrointestinal motility and the secretion of various digestive enzymes, and improve the digestion and utilization of feed by livestock and fish, thereby improving production performance and reducing feed costs.
Under the action of enzymes, allicin can be converted into alliin and excreted in the form of feces and urine, which can prevent the reproduction and growth of pests in farming and improve the environment of pens and ponds.
(II) Usage methods and dosage of allicin. Adding fresh garlic. Most commonly, fresh garlic is mashed, chopped, or ground into garlic paste using a meat grinder, and then added to the feed. Alternatively, fresh garlic is mixed with feed ingredients and then crushed. The proportion of fresh garlic added to feed is 1%-10%, added according to the size of the livestock and poultry, generally divided into three categories: small, medium, and large (i.e., small 1%-2%, medium 2%-4% or 5%-6%, large 8%-10%).
(III) Application effects of allicin in livestock production. The author conducted trials at the county's foreign trade breeding hen farm. Compared with breeding hens fed feed without added allicin, adding 50, 67, 84, and 100 mg of allicin per kg of daily ration increased the egg production rate by 2.73%, 5.95%, 11.10%, and 7.83% respectively, with significant differences. Trials on dairy cows showed that allicin can give concentrated feed a rich natural aroma and has a strong feeding-attractant effect on dairy cows. Statistics show that the daily milk yield per dairy cow can be increased by 2.28 kg, the intake of roughage can be reduced by 0.08 kg/day, and income can be increased by 6-8 yuan per day. In trials on lactating sows, it was found that allicin can increase feed intake in pigs. Trials on piglets weaned at 15-28 days showed that feeding feed with 100 mg/kg of added allicin increased the daily weight gain of piglets and reduced the feed-to-meat ratio, with significant differences compared with piglets fed feed without added allicin.
(IV) Effects of allicin in fish production. Yanxia Reservoir in Tongshan County, Hubei Province, fed tilapia with allicin at 500 mg/kg for 45 days and found that allicin has a strong feeding-attractant effect; feed conversion improved by 11%, the comprehensive biological evaluation value of the feed increased by 12%, the survival rate increased by 2%-5%, and the weight gain rate also increased to some extent. Rujiatian Reservoir in Tongshan County found that allicin has a very good feeding-attractant effect on crucian carp, grass carp, and common carp. The Enan Feed Additive Technology Development Service Center in Hubei Province used air-dried garlic bulbs with roots, ground them into powder with a meat grinder, heated and distilled them to obtain a mixed liquid of oil and water, and after separation obtained garlic oil, which was added at 0.008% of the bait weight to feed grass carp; the survival rate increased by more than 15%, and feeding tilapia increased weight gain by 10%-15%.
(V) Application prospects of allicin. Based on the above practices, allicin can significantly improve production performance, reduce the incidence of disease, reduce mortality, and increase farming benefits. It can partially replace antibiotics, thereby reducing microbial drug resistance, and has beneficial effects on the health of livestock and fish. Adding allicin to feed can serve as one approach to solving the antibiotic problem.