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Water is an indispensable and irreplaceable nutrient for animals. The digestion and absorption of feed, the transportation and metabolism of nutrition, the excretion of feces and urine, the growth and reproduction, the lactation and other processes must involve water. Safe and scientific water supply is of great significance to pig production.
At present, many pig farms only pay attention to the quantity of water supply and neglect the quality of water. In the process of water intake and supply, there is a lack of effective protection and disinfection, which makes it difficult to control water-borne diseases, especially diarrhea diseases. So we have to borrow pig equipment to supply water. It is understood that at present, the water for pig breeding in rural and suburban areas mainly comes from untreated rainwater and polluted untreated groundwater. If such water is used for large-scale pig breeding, it will certainly harm the health of pigs, even the health of breeding and management personnel. Therefore, we should attach great importance to the regular detection and continuous disinfection of drinking water in large-scale pig farms.
In order to standardize the safety standards of water for farms, our government has also issued a series of standards for drinking water for livestock and poultry in recent years. According to the agricultural industry standard of the people's Republic of China green agricultural animal health standard (NY / t473-2001), the quality of drinking water for livestock and poultry should meet the requirements of the sanitary standard for drinking water (gb5749-85) officially issued by China, and the quality of drinking water for livestock and poultry in pollution-free food（ Ny5027) also has clear regulations on the quality of drinking water for livestock and poultry. In addition to specific regulations on the physical and chemical indicators and detection methods of drinking water, the standards for microorganisms in drinking water are: total bacteria < 100 / ml; total coliform group < 3 / L. See Table 2
The problem of water quality is mainly related to microbial pollution and nitrite content. The pathogenic microorganism in water has a great influence on the health of pigs. Among the diseases of swine, the water mediated diseases include viral diseases, bacterial diseases and parasitic diseases. The viral diseases mainly include swine fever, foot-and-mouth disease, infectious gastroenteritis, epidemic diarrhea, rotavirus disease, PRRS, PR, and reovirus; Bacterial diseases mainly include carbon blast, Leptospira, Escherichia coli, erysipelas suis, Salmonella, Brucella, Streptococcus, swine dysentery, Clostridium perfringens type C, proliferative enteropathy, Staphylococcus, etc.; parasites mainly include Ascaris, arthroderma, coccidiosis, whipworm, etc., and there are about 20 kinds of diseases that can be transmitted by water. These diseases do not exist in a pig farm at the same time, but there are many waterborne infectious diseases in the same pig farm at the same time, and they exist in the pig farm for a long time and continuously lead to the occurrence of diseases in the pig herd. Nitrates exist in surface and underground water. Nitrates can be converted into nitrites, which are toxic. No toxicity was produced until nitrate was transformed into nitrite. The concentration of nitrite in water below 100mg / kg is safe, but when the concentration of nitrate in water is higher than 100mg / kg, hemoglobin can be converted into methemoglobin. Methemoglobin in the blood can not transport enough oxygen to the tissues. If the content of methemoglobin in the blood is too high, it may lead to the death of pigs. In addition, surface water and groundwater contain many mineral elements, such as iron, sulfur, chlorine and magnesium. These minerals can form complex with calcium, magnesium, sodium and so on to form the total soluble substances in water. When the total soluble substances in water exceed 5 g / L, it will cause diarrhea in pigs and affect their production performance.