A Complete Analysis of Differential Diagnosis Methods for 10 Swine Diarrheal Infectious Diseases
Differential Diagnosis of 10 Swine Diarrheal Infectious Diseases, So Comprehensive, Save It Now!
1. Piglet red diarrhea
Epidemiological characteristics: It mainly affects newborn piglets from 1 day old to 3 days old. The course of disease is short and the mortality rate is high. Piglets over 1 week old rarely develop the disease.
Characteristic symptoms and lesions: Sudden passage of bloody diarrhea or red-brown loose stool, occasionally vomiting, weak constitution, and rapid death. The characteristic lesions are mainly in the jejunum, which appears dark red on the outside, and the intestinal cavity is filled with blood-containing fluid. The mesenteric lymph nodes are bright red. Sometimes the lesions can extend to the ileum, but the duodenum generally has no lesions.
Laboratory testing: Isolating only the pathogen is of little significance, because this bacterium is ubiquitous in the external environment. The key is to perform a serum neutralization test to confirm the presence of Clostridium welchii type C toxin in the intestines of diseased pigs.
Prevention and control: This disease occurs acutely and death is rapid, so there is often no time fortreatmentortreatmentis not effective. It mainly relies on the routine use of sensitive drugs for prevention. ⟦14 2. Piglet yellow diarrhea
2. Piglet yellow dysentery
Epidemiological characteristics: It mainly occurs in piglets within 1 week of age, especially around 3 days of age. Both the morbidity and mortality rates are very high. Piglets over 7 days of age are less affected. Sows carrying pathogenic Escherichia coli are an important factor in the occurrence of this disease.
Characteristic symptoms and lesions: Sudden onset, passage of yellow mucous-like loose stool or watery stool, mixed with curd-like small pieces and bubbles. The intestines contain a large amount of yellow liquid content and gas. The intestinal mucosa shows acute catarrhal inflammation, most severe in the duodenum, followed by the jejunum and ileum, and milder in the colon.
Laboratory testing: Collect the contents of the anterior segment of the small intestine for bacterial isolation, culture, and identification. Farms with conditions can also perform enterotoxin testing.
Prevention and control: Comprehensive measures focusing on improving feeding management and strengthening sanitation and epidemic prevention are adopted. Sensitive drugs selected through drug sensitivity testing are used forprevention and control, or microecological preparations may be used. Genetically engineered Escherichia coli vaccines can also be used to immunize sows twice before farrowing for prevention.
3. Piglet white diarrhea
Epidemiological characteristics: It usually occurs in piglets from 10 days old to 30 days old, most commonly from 10 days old to 20 days old. It can occur throughout the year, with a relatively high morbidity rate but a low mortality rate. Poor feeding management and poor sanitary conditions are external causes of the disease.
Characteristic symptoms and lesions: Passage of gray-white, paste-like loose stool with a fishy odor. The intestines contain varying amounts of chyme and gas. The intestinal mucosa is congested and hemorrhagic, and the intestinal wall becomes thin.
Laboratory testing: Escherichia coli is isolated from the small intestine and identified by serological methods.
Prevention and control: Basically the same as for piglet yellow diarrhea, but there are more factors affecting the occurrence of this disease. Clinical investigation and analysis should be conducted to identify predisposing factors and overcome them. On this basis,treatmentcan only be effective.
4. Swine dysentery
Epidemiological characteristics: It is most commonly seen in growing pigs from 2 months old to 3 months old after weaning. The morbidity rate is high, the mortality rate is relatively low, and piglets and adult pigs are less affected. There is no seasonality. It spreads slowly, has a long epidemic period, and is prone to relapse. Various stress factors can promote the occurrence and spread of this disease.
Characteristic symptoms and lesions: Diarrhea of varying degrees, with feces full of blood and mucus, appearing brown, red, or black. The large intestinal mucosa develops catarrhal hemorrhagic inflammation, which then progresses to fibrinous necrotizing enteritis.
Laboratory testing: Collect diseased material for direct dark-field microscopy, stained microscopy, or isolation and culture, and identify Brachyspira hyodysenteriae based on morphology, motility characteristics, and culture characteristics.
Prevention and control：treatmentis not effective, while earlytreatmentis effective. It mainly relies on routine prevention. Sensitive antibacterial drugs can be selected, such as mequindox, tetracyclines, or quinolones.
5. Swine paratyphoid
Epidemiological characteristics: It mainly affects piglets from 2 months old to 4 months old, especially piglets shortly after weaning, which are most susceptible. Adult pigs and suckling piglets rarely develop the disease. There is no obvious seasonality, and it occurs sporadically and enzootically.
Characteristic symptoms and lesions: The acute type first has constipation and then diarrhea, with foul-smelling feces, and cyanosis of the skin of the ears, abdomen, and limbs. The chronic type is the most common, with repeated diarrhea, and the feces are porridge-like or watery, yellow-brown, gray-green, or dark brown, with a foul odor. In some cases, eczema-like papules appear on the chest and abdomen. Necropsy shows that the acute type mainly involves septicemic changes; the chronic type mainly shows sunken irregular ulcers and pseudomembranes in the cecum and colon, and gray-white necrotic foci ranging from needle-tip size to millet-grain size in the liver, lymph nodes, and lungs.
Laboratory testing: Collect diseased materials such as liver and spleen for bacterial isolation and identification, also called immunofluorescence testing.
Prevention and control: Importance should be attached to the implementation of comprehensive veterinary hygiene measures. For prevention, piglet paratyphoid vaccine can be inoculated, or sensitive drugs can be added during the susceptible age period.treatment, in addition to selecting sensitive drugs, symptomatictreatmentshould also be supplemented for chronic cases with a longer course of disease and weaker constitution, such as fluid replacement (oral rehydration salts), detoxification (0.5% sodium bicarbonate injection), cardiac support (caffeine sodium benzoate, calcium chloride injection), astringency (charcoal powder, tannalbin), and tonification (glucose injection, vitamin C), etc.
6. Rotavirus infection
Epidemiological characteristics: It occurs more frequently in the cold seasons of late autumn, winter, and early spring, and often occurs as a mixed infection with piglet white diarrhea. It mostly occurs in piglets under 8 weeks of age, especially from 10 days old to 28 days old. The mortality rate is relatively low, and adult pigs are mostly subclinically infected.
Characteristic symptoms and lesions: Piglets have anorexia, vomiting, and diarrhea. The feces are yellow, gray, or black, watery or paste-like. The lesions are mainly limited to the digestive tract. The stomach wall is flaccid, the stomach is filled with curds and milk, the intestinal wall becomes thin, and the contents are gray-yellow or gray-black liquid.
Laboratory testing: Rotavirus can be detected using fluorescent antibodies against rotavirus or immunoelectron microscopy.
Prevention and control: There is no specific therapy, and symptomatictreatmentmay be used. Prevention mainly relies on strengthening feeding management, conscientiously implementing general veterinary epidemic prevention measures, and enhancing the resistance of sows and piglets. In epidemic areas, newborn piglets should be allowed to consume enough colostrum as early as possible to receive the protection of maternal antibodies and reduce and alleviate the disease.
7. Transmissible gastroenteritis
Epidemiological characteristics: It mostly occurs in the cold seasons of winter and spring. Pigs of all ages are susceptible. The morbidity and mortality rates of piglets within 10 days of age are both very high. Diseased pigs over 5 weeks of age rarely die, and older or adult pigs almost never die.
Characteristic symptoms and lesions: Piglets suddenly vomit, have watery diarrhea, and become dehydrated. Adult pigs have mild symptoms, showing only anorexia and short-term diarrhea. The stomachs of piglets are filled with curds, the mucosa of the gastric fundus is mildly congested, the small intestine is congested, with foamy fluid and undigested curds, and the intestinal wall becomes thin and translucent.
Laboratory testing: Immunofluorescence antibody testing, piglet inoculation testing, and serum antibody monitoring can all be used for this disease.
Prevention and control: There is no specific therapy. Antibacterial drugs can be used to prevent secondary or concurrent infections, and symptomatic therapies such as astringency, antidiarrheal treatment, cardiac support, fluid replacement, and tonification can be used. For prevention, attenuated vaccine can be used to vaccinate all pigs on the farm before the epidemic season of this disease, or inactivated vaccine can be used to immunize sows so that piglets obtain passive immunity from milk.
8. Porcine epidemic diarrhea
Epidemiological characteristics: It mostly occurs in cold seasons. Pigs of all sizes develop diarrhea almost simultaneously. Adult pigs can recover within a few days, while some piglets die.
Characteristic symptoms and lesions: Vomiting, watery diarrhea, obvious dehydration, and greatly reduced appetite, very similar to swine transmissible gastroenteritis. The lesions are limited to the small intestine. The intestinal tract is dilated and contains a large amount of yellow liquid, the intestinal wall becomes thin, and the mesenteric lymph nodes are edematous.
Laboratory testing: Fluorescent antibodies against porcine epidemic diarrhea virus or immunoelectron microscopy can be used to detect porcine epidemic diarrhea virus antigen or virus.
Prevention and control: At present, there is no specific therapy. Attenuated or inactivated porcine epidemic diarrhea vaccine can be used for preventive injection. The generaltreatmentmethods are the same as for swine transmissible gastroenteritis.
9. Coccidiosis
Epidemiological characteristics: It occurs more frequently in warm and humid seasons. Piglets from 7 days old to 21 days old are most susceptible. In particular, piglets raised in dark, humid, and poorly sanitized pig houses have a higher morbidity rate.
Characteristic symptoms and lesions: Passage of earth-gray, yellow gelatinous or watery loose stool, mixed with a large amount of mucus and undigested feed. The jejunum and ileum show catarrhal inflammation, the intestinal wall thickens, and mucous exudate adheres to it or necrotic lesions appear.
Laboratory testing: Use the saturated saline flotation method to examine oocysts in feces.
Prevention and control: Creating a good sanitary environment and preventing sows from shedding oocysts are the keys toprevention and controlof this disease. Sulfonamides or amprolium can be selected fortreatment。
10. Iron deficiency anemia
Epidemiological characteristics: There is no obvious seasonality. It occurs more frequently in pig farms where the pig house floor is made of wood boards or cement and no iron supplementation measures are taken. Piglets from 15 days old to 30 days old often develop the disease in large numbers.
Characteristic symptoms and lesions: Decreased appetite, emaciation, mucous membranes as pale as white porcelain, ear shells appearing gray-white under light with almost no visible blood vessels, and alternating diarrhea and constipation. Necropsy shows markedly pale skin and mucous membranes, sometimes with mild yellow staining, and pleural and abdominal effusion. Parenchymal organs show fatty degeneration, the blood is thin, the muscles are pale, and there are inflammatory lesions in the gastrointestinal tract and lungs.
Laboratory testing: Blood testing shows that both hemoglobin and red blood cell counts are decreased.
Prevention and control: Oral or injectable iron supplements can be used, such as iron dextran, iron-cobalt compound, and iron dextran preparations. Timely iron supplementation for piglets at 3 days of age has a reliable preventive effect.