Common causes of liver rupture and bleeding in laying hens

1. Liver rupture process

As an important nutritional and detoxifying organ, the liver is damaged by toxins, viruses, and bacteria. The first step is to undergo a compensatory hyperplasia stage, that is, liver enlargement (some diseases seriously damage the liver and do not show swelling stage); The second step is the formation of lesions in the liver tissue, such as fatty liver cells, blood vessel wall damage, hemangioma formation, tissue brittleness, etc.; the third step is quantitative changes leading to qualitative changes. When liver lesions reach a certain level, the liver is seriously damaged and thrombin Insufficient secretion of blood leads to decreased coagulation ability of the blood. Once there are predisposing factors such as strenuous exercise, squeezing, trampling, abnormal egg production and defecation, liver rupture, massive bleeding, and subsequent death can occur.

2. Causes of liver rupture and bleeding

2.1 Viruses

2.1.1 Hepatitis E infection

It is the main cause of hepatitis-splenomegaly syndrome, which can lead to liver and spleen enlargement and bleeding. The symptoms of this disease are mild in the early stage of infection alone, and the mortality rate is not high. However, the onset period is long and can lead to a mortality rate of 90% in the entire population after 100 days. The situation can be serious when mixed with other illnesses.

2.1.2 Adenovirus

Adenovirus infection, also known as inclusion body hepatitis, can cause liver deformation, necrosis and cell changes. It can also cause a 10% decrease in egg production, slow growth, excessive fat deposition, decreased cholesterol and triglyceride levels, and cause respiratory symptoms, Tenosynovitis.

2.1.3 Avian leukemia

It can lead to significant enlargement and hardening of the liver, with diffuse gray tumor infiltration, causing the liver to appear mottled or granular, making the liver very brittle, and causing thrombosis in the liver and spleen, causing infarction and rupture. In some cases, multiple hemangioma may occur in internal organs, which may rupture and bleed easily.

2.2 Bacteria

2.2.1 Campylobacter jejuni

When poultry is naturally infected, there are usually no clinical symptoms, but when mixed with other diseases or when the immunity of the chickens is extremely low, it can lead to vibrio hepatitis, liver enlargement, necrosis and bleeding.

2.2.2 Salmonella pullorum

It can lead to enlargement and congestion of the liver, spleen, and kidneys, and sometimes ascites. Chicks may die suddenly without symptoms. The main pathological changes in adult chickens include deformation and discoloration of follicles, cysts or nodules, caseous exudation of fallopian tubes, and fibrous Peritonitis and perihepatitis; pericarditis, pericardial transparency decreases and thickens, and pericardial fluid turbidity increases.

2.2.3 Avian cholera

It can cause liver enlargement, and multiple small focal coagulation necrosis areas and heterophil cell infiltration areas can be seen.

2.2.4 Streptococcus septicemia

It can cause liver congestion and swelling, with red, brown, and white necrotic lesions ranging from corn-shaped to 1 cm in size.

2.2.5 Staphylococcus aureus

Can cause multiple organ necrosis (including liver) and granuloma.

2.3 Protozoal diseases

Such as histomoniasis (blackhead disease), leukoprotozoa, etc.

2.3.1 Histomoniasis

Also known as infectious cecal hepatitis or blackhead disease. This disease generally does not have serious consequences when it exists alone. However, when combined with other pathogenic bacteria, such as Eimeria tenella, Escherichia coli, Clostridium, etc., severe lesions may occur. The main diseased organs are the cecum and liver; the cecal wall It becomes thickened, congested, has a large amount of exudate, and gradually cheeses, eventually forming a cheese-like intestinal core; the liver forms a round and sunken necrotic focus, which is swollen and turns green or yellow-green.

2.3.2 Leukocytosis

Also known as white coronavirus, it can cause systemic bleeding and extensive bleeding in internal organs such as liver, lungs, and kidneys. Some internal organs and muscle tissue have small white nodules (merozoites).

2.4 Poisoning

Such as mycotoxin poisoning, drug poisoning, etc.

2.4.1 Mycotoxin poisoning

Mycotoxins are mainly toxic and harmful substances produced by molds, including ergot alkaloids, aflatoxins, trichothecenes, fusarium toxins, ochratoxins, oosporin, citrinin, and fumagillin It can lead to liver poisoning, tissue hyperplasia, multifocal necrosis and bleeding, tissue structure destruction and protein and DNA synthesis obstruction, liver necrosis, degeneration, liver failure, hepatocyte vacuolization, and liver color white, yellow-green. The liver tissue undergoes compensatory hyperplasia and swelling in the early stage and atrophy in the later stage. This disease occurs frequently, and the problem of feed mold should be checked first when diagnosing.

2.4.2 Drug poisoning

For example, sulfonamide drug poisoning can cause extensive bleeding in the skin, muscles, and internal organs, and the liver will be enlarged and appear light red or jaundice, with scattered petechiae and focal necrosis.

2.5 Nutritional and metabolic diseases

For example, fatty liver syndrome, also known as fatty liver hemorrhage syndrome, is a nutritional and metabolic disease with complex causes. It occurs frequently during the peak egg production period. It can cause liver rupture, blood or blood clots in the abdominal cavity, and liver enlargement and edges. Blunt, greasy and greasy, brown or light yellow, brittle.

2.6 Other reasons

2.6.1 Stress

Such as group transportation, vaccination, temperature changes, feed changes, poor ventilation, etc.

2.6.2 Changes in physiological stages

Such as starting production or entering peak period.

2.6.3 Infection with some other diseases

Leading to decreased immunity or collapse of the immune system.

3. Preventive measures and treatment measures

3.1 Carry out on-site disease purification, start with the introduction of high-quality chicks, and refuse to buy one get one free or buy one get two free.

3.2 Carry out on-site environmental control to reduce the total number of bacteria and viruses per unit area in the site.

3.3 Try to reduce, alleviate or avoid various stresses.

3.4 Ensure adequate drinking water and hygiene.

3.5 Provide high-quality balanced diets to ensure no mildew and sufficient and reasonable vitamins and trace elements. Add less and more frequently, and add as much as you eat to ensure nutrition, reduce waste, and avoid mildew.

3.6 Needles should be changed frequently during epidemic prevention to avoid artificial spread of diseases.

3.7 According to the physiological stage of laying hens, some anti-stress, liver-protecting and kidney-protecting drugs are regularly used for prevention.

3.8 If you do not take care of your illness, you should actively treat it if you find signs of it to prevent secondary infections. If possible, the cause should be investigated and traced, and samples should be sent to the laboratory to isolate the virus strain/strain for diagnosis.

3.9 If you are found to be infected with a disease that has no therapeutic value, you must decisively stop losses and eliminate the entire group.