(1) bacterial diarrhea 1. Piglet red dysentery: Piglet red dysentery is caused by the toxin produced by Clostridium welchii type C, which mainly occurs in piglets under 3 days old and can occur all year round. Pigs with this disease are characterized by red feces and intestinal mucosal necrosis. Sick pigs have low spirits, loss of appetite, bleeding and dysentery. The feces of some sick pigs contain necrotic tissue fragments and small bubbles, which are smelly. Most of the cases are acute, with rapid onset, short course of disease and high mortality in pigs. The death time of the most acute cases is 1 ~ 2 days, the death time of acute cases is 5 ~ 7 days, and a few chronic cases have intermittent or persistent diarrhea. Autopsy showed that the intestinal cavity was full of blood samples, the intestinal mucosa was congested, bleeding and easy to fall off, the mesentery was congested and the mesenteric lymph nodes were bright red and swollen. 2. Yellow scour of piglets: The pathogen of yellow scour of piglets is Escherichia coli, which mainly occurs in piglets born within 65,438+0 weeks, and piglets born at the age of 65,438+0 ~ 3 days are the most common. This disease is more common in summer. Sick pigs are depressed, lose appetite, dry mouth, lose weight quickly, and discharge yellow or yellow-white paste feces, which contain small pieces of coagulated milk and have a bad smell. In severe cases, the pig's anus is slack, fecal incontinence, tail, perineum and hind legs are dirty, and the anus is red or purple. At autopsy, the dead pig showed intestinal swelling, a large amount of yellow liquid contents and gas, and acute catarrhal inflammatory changes in intestinal mucosa, with duodenum being the most serious, jejunum and ileum being the second, and colon being the lighter. 3. Piglet dysentery: Piglet dysentery is caused by Escherichia coli infection. Severe climate change, rainy and humid weather, insufficient milk for sows, and too thick or thick milk will all cause the disease. The disease mostly occurs in piglets aged 7-30 days, especially in piglets aged 7- 14 days, and the disease is more serious. Piglets over 1 month are rare, and the course of disease is usually 2-7 days. Sick pigs are characterized by discharging white or grayish white pasty or pasty malodorous feces. The sick pig has a hunched back, rough fur and messy anus covered with feces. Autopsy of dead pigs showed that the colon contents were pasty, pasty or ointment, milky white or grayish white, and some of them adhered to the mucosa, which was not easy to be completely peeled off. Catarrhal inflammatory changes occurred in intestinal mucosa, and mesenteric lymph nodes were slightly swollen. 4. Swine dysentery: Swine dysentery is caused by the interaction between treponema suis and anaerobic bacteria in the intestine. It mostly occurs in piglets aged 7- 12 weeks. The body temperature of sick pigs reached 40-4 1℃ at the beginning of the disease, and yellow or gray soft stools were discharged, and soon the food was reduced. In the later stage, the feces are watery, often mixed with blood, mucus and mucosa, and then the feces are oily or peptone-like. The sick pig hunched his back and hung his stomach, losing weight rapidly, losing appetite and increasing thirst. Finally, the sick pig died because of dehydration failure. 5. piglet paratyphoid: piglet paratyphoid is caused by salmonella. It mostly occurs in piglets aged 2-4 months. The occurrence of the disease has no obvious seasonality, and it mostly occurs in rainy and humid seasons. Acute cases show symptoms of septicemia. Pigs suddenly get sick, their body temperature rises, they lose appetite, constipation occurs at the initial stage of the disease, and then diarrhea, which leads to foul smell and loose feces. Two to three days after the onset, the sick pig's nose, ears and inner skin of limbs turned purple, and the sick pig became listless, bowed his head and stood still, his gait trembled, his body temperature dropped, and he died soon. Chronic diseases are the most common diseases. The sick pig's body temperature rose slightly and he was listless. Constipation at the beginning of the disease, followed by persistent or intermittent diarrhea. Yellow or yellow-green odor and loose stools mixed with blood, necrotic tissue or cellulose flakes are discharged, and sick pigs gradually lose weight. Autopsy of dead pigs: Acute cases show septic pathological changes; chronic cases show diffuse necrosis and erosion, with a layer of grayish yellow or yellowish green chaff on the surface, rough and thickened intestinal wall, and needle-like grayish yellow necrotic foci or grayish white nodules are often seen in liver, spleen and mesenteric lymph. Supplementary answer:

(2) Viral diarrhea

1. Porcine epidemic diarrhea (PEDV): Porcine epidemic diarrhea mainly occurs in the cold season of late winter and early spring, and it occurs more frequently from 10 to March of the following year. Pigs of all ages are susceptible to infection, but piglets under 1-5 days old have the highest infection rate, the most serious symptoms and the highest mortality rate. The sick pig's body temperature is normal or slightly elevated, and it is listless and has a decreased appetite. Older pigs have mild symptoms, while younger pigs have severe symptoms. Piglets often vomit at the early stage of onset, discharge gray or yellow porridge or watery stool, and have a bad smell. Autopsy showed that the small intestine was full of yellow contents, the intestinal wall became thinner, the mesentery was dendritic congestion, and the mesenteric lymph nodes were edema.

2. Swine transmissible gastroenteritis (TGEV): Swine transmissible gastroenteritis is easy to infect pigs of all ages, but it is more common in pigs under 2 weeks old, and the mortality rate is higher. Sick piglets often vomit after sucking breast milk, and soon they have severe diarrhea, yellow or gray watery stools, and the feces are often mixed with undigested curd, which smells bad. The younger the sick pig, the shorter the course of disease and the higher the mortality rate.

3. Rotavirus disease (PVV): Rotavirus disease is the most common in late winter and early spring, which mostly occurs in piglets under 2 months old, with a mortality rate of more than 50%. Sick pigs are depressed, unwilling to walk, often vomit after eating, discharge yellow or taupe water samples or pasty loose stools, and often die within 3-7 days due to diarrhea and dehydration.

In addition, piglets with classical swine fever and pseudorabies also have diarrhea symptoms, but pigs with classical swine fever generally have constipation and diarrhea alternately.

(3) Parasitic diarrhea Piglet diarrhea caused by parasitic diseases is often caused by coccidia, roundworms and trypanosomes, which are more common in pigs over 20 days old. Generally speaking, pigs will suffer from chronic diarrhea. Usually, sick pigs will have diarrhea, accompanied by symptoms such as loss of appetite, cough, dyspnea and anemia. Some cases of diarrhea and constipation appear alternately, and some cases are accompanied by symptoms of elevated body temperature. Sick pigs are stunted, gradually lose weight, die of exhaustion or form "stiff pigs".

Non-disease diarrhea

1. Too high content of protein in piglet feed causes piglet diarrhea: due to the imperfect digestive function of suckling piglets and weaning piglets, due to insufficient secretion of digestive enzymes, the pH value of stomach contents is high (the normal pH value of pig stomach contents is 3 ~ 4, while the pH value of piglet stomach contents is 5 ~ 7), the development of small intestinal villi is slow, and the pepsin activity is low, so the piglet's ability to absorb and utilize protein is poor. For example, the high content of protein in the feed of suckling piglets and weaning piglets will not only waste the feed on protein, increase the feeding cost of piglets, but also easily lead to indigestion and diarrhea of piglets.

Supplementary answer: 2. Excessive crude fiber content in feed leads to diarrhea in piglets: pigs are omnivores. Appropriate crude fiber content in pig feed can promote gastrointestinal peristalsis and enhance digestive function of pigs, but excessive crude fiber content in pig feed will be counterproductive, especially for piglets. If the content of crude fiber in piglet feed exceeds 4%, it will not only reduce the ability of piglets to absorb nutrients, but also easily cause diarrhea in piglets.

3. Lack of nutritional factors leads to piglet diarrhea: Piglets lack vitamins (such as folic acid, nicotinic acid, pantothenic acid), minerals or other essential nutrients (such as trace elements of zinc, selenium, iron and copper), which will lead to decreased piglet resistance and diarrhea. Sick piglets excrete pale yellow, white, gray-green paste or watery stench and thin feces.

4. Diarrhea of piglets caused by stress factors: Because the immune system and digestive system of piglets are not well developed, piglets are very sensitive to various stress factors, such as separation of mother and child after weaning, changes in feed, changes in the same group of piglets, immunity, castration, temperature, humidity, environmental changes, etc., which will cause a series of stress reactions, and eventually lead to reduced feed intake and indigestion of piglets, resulting in diarrhea.

In addition, feeding piglets with moldy and deteriorated feed, frozen feed and undercooked bean products is easy to cause poisoning and diarrhea.

Second, toxic diarrhea in piglets

Once diarrhea occurs in piglets, the gastrointestinal tract of piglets will be damaged to varying degrees. Even after treatment, the gastrointestinal function of piglets will be difficult to return to normal, which will directly affect the digestion and absorption of nutrients, resulting in different degrees of decline in feed reward and weight gain. Therefore, in order to effectively prevent the occurrence of piglet diarrhea, a series of comprehensive prevention and control measures must be taken on the basis of adhering to the principle that prevention is more important than treatment. Specifically, the following comprehensive prevention and control measures can be taken to prevent piglet diarrhea:

(1) Do a good job of vaccination to enhance the immunity of piglets. Pregnant sows were injected with/kloc-0 vaccine (K88K99 vaccine) about 2 1 day before delivery, and polyvalent piglets were taken orally 1 2 days after birth to stop diarrhea. In addition, farms (households) should selectively inject piglets with Clostridium welchii, porcine epidemic diarrhea, porcine transmissible gastroenteritis and rotavirus vaccine according to the local epidemic situation to enhance the immunity of piglets.

(2) Do a good job in environmental sanitation to prevent germs from invading farms (households). They should establish a strict and perfect disinfection system, regularly disinfect the environment, pigsty and utensils, and regularly clean and disinfect sow breasts. Especially, before piglets suck breast milk for the first time 1 time, they should use 0. 1% potassium permanganate solution to clean and disinfect the dirt on the nipples and abdomen of sows. In order to nip in the bud, you can use.