Viral diseases of birds. How to recognize bird pox? Bird pox. Common infectious diseases of chickens (infectious and invasive): symptoms, treatment and prevention Infectious diseases of exotic wild birds

Smallpox

In canaries, smallpox has been known for a very long time and its course is severe. Under natural conditions, smallpox has been recorded in guinea fowl, pheasants, peacocks, ornamental birds and songbirds. Of the free-living birds, the infection was found in sparrows, doves, wood accentors, and ostriches. Smallpox causes the greatest economic losses to canary farmers, leading to mass death of birds. Sparrows and finches were sensitive to the canarypox virus. 10-14 days after the incubation period, clinical signs of the disease appear, occurring in various forms. Often dies suddenly, without visible clinical signs. At autopsy, pinpoint hemorrhages are revealed in the lungs and cardiac muscles. The acute pulmonary form is accompanied by severe shortness of breath, conjunctivitis, blepharitis and rhinitis. Poultry farmers call this disease breathlessness disease. There are thickenings of the skin in the corners of the beak, under the beak, on the neck and head, the mucous membranes of the nasal cavity and larynx are very red and inflamed. In males, deposits form on the beak, eyes, wings and legs. Bubbles containing a clear liquid form on the eyelids of the eyes, which later turns blood red. Death occurs within 2-3 days. At autopsy, swelling of the liver and an increase in the volume of the spleen are determined.

Sometimes smallpox proceeds in a peculiar way, with the formation of dense formations in the feather follicles located in the chest area, on the wings; at autopsy, pericarditis and diphtheroid deposits on the cardiac membrane are found in dead birds, pericarditis, and clouding of the walls of the air sacs.

The chronic form of smallpox usually occurs in the form of skin lesions. Pockmarks form on transverse areas of the body (wings, beak, eyelids, eyes, sole, foot). The general condition of the bird is impaired, and the toes may fall off. Usually this disease lasts about 3 weeks and only when tumors develop does the disease prolong.

The diagnosis should be made on the basis of clinical signs, histological studies of the skin, lungs, trachea, and detection of Bolinger bodies. As a preventive measure, active immunization is recommended, which is carried out with a weak homologous canary virus. Inactivated strains of the smallpox virus do not create intense immunity.

Newcastle disease

This disease is most dangerous for chickens, turkeys, and guinea fowl, but can affect all species of parrot birds and some species of granivores. The literature describes many cases of Newcastle disease in gray parrots, Amazons, quails, and pheasants.

Free-living birds are susceptible to Newcastle disease. The disease has been recorded in sparrows, jackdaws, blackbirds, goldfinches, starlings, crossbills, bullfinches, Muscovy tits, greenfinches, chaffinches, hawks, sparrow hawks, owls, kestrels, and pygmy owls.

Etiology and properties of the pathogen. The disease is caused by a filter virus; it has hemagglutination properties against the red blood cells of pigeons, chickens, turkeys, frogs, and guinea pigs. This property is used to study isolated strains and typify the virus in experiments with the hemagglutination delay reaction (RDHA).

Based on their hemolytic activity, virus strains are divided into highly active and weakly active. The virus is easily cultivated on 9-12-day chicken embryos and tissue cultures.

In addition to the Newcastle disease virus, there is a virus in nature that causes classical plague (European plague), but it is distinguished by the lack of hemolytic activity, sensitivity to acidic environments (pH 5.0) and antigenic properties when staging CSC and precipitation.

The resistance of the pathogen to the action of physical and chemical factors depends on the protein environment in which the viral particle is located and the pH of the environment.

In summer, the virus dies in bird corpses after 30 days, and in frozen corpses it persists for over 300 days. The action of disinfectants is usually quickly killed by a 3% solution of bleach, 2% sodium hydroxide, 4-5% solution of xylonaftha.

The bird becomes infected through nutritional and aerogenic methods. The virus is released from the mucus of the upper respiratory tract and oral cavity, with droppings, infecting the environment. The virus is able to be released during the incubation period 24 hours after infection of the bird, but it can be detected in the body of recovered birds within 5-7 days after recovery. In a protracted process involving damage to the nervous system, the virus is localized for a long time in the brain.

Clinical signs vary depending on the virulence of the epizootic strains of the virus, the age of the bird and the conditions of detention that influence the course of the disease. In the typical course of Newcastle disease, there is an increase in temperature by 1-2°C, decreased appetite, lethargy, and drowsiness. Damage to the respiratory system in the form of suffocation is observed in 40-70% of sick birds, intestinal disorders - in 88% (with the release of liquid feces, colored green). Often viscous mucus is released from the oral cavity, the bird sneezes and makes swallowing movements. Massive cases of conjunctivitis caused by the pseudoplague virus have been established. Acute cases of the disease are often accompanied by the death of the bird.

In addition to the acute form of the infection, numerous cases of mild and asymptomatic infection are currently being recorded. At the same time, it can be very difficult to determine the degree of coverage.

Clinical symptoms are not typical: loss of appetite, diarrhea, rhinitis, conjunctivitis and shortness of breath. Only in individual birds do severe disorders of the central nervous system occur: neck crooking, muscle tremors, ataxia and paralysis. In experimentally infected wild birds, the disease occurs mainly in the form of nervous symptoms; in sparrows and jackdaws - movement disorders, convulsions, in hawks - convulsions. All birds of prey had blood that was virulent for chickens.

In sparrows that spontaneously become ill with Newcastle disease, ataxia is observed, body swaying, loss of balance, which they try to restore by leaning on their wings; convulsions with stretching of the head and neck, even drowsiness and coma. In dead parrots, swelling of the lungs, brain, and serous pericarditis is found. The disease progresses very quickly, death occurs within 3 days. Before death, symptoms of apoplexy are noted, accompanied by the leading clinical sign in the form of twisting of the neck, paralysis of the legs and wings, and convulsions. In some birds, the disease passes in a latent form without clinical signs, but such birds pose a great danger as a source of infection. Elucidation of the causes of the latent and atypical course of infection showed that their appearance depends on the presence of weakly virulent strains of viruses in natural conditions, varying degrees of immunity in infected birds, the widespread use of antibiotics and other factors.

Much work on the isolation and typification of naturally weakened strains of viruses has been carried out by many researchers in various countries. As a result, several strains were isolated: Vie “La Sota”, “Florence”. These virus strains often do not cause clinical signs of disease, but the presence of antibodies can be detected by testing the blood serum of infected birds.

Pathological changes. At autopsy, hemorrhages are found on the mucous membranes of the stomach, intestines, and serous covers of the peritoneum.

In the subacute course of the disease, inflammation of the air sacs, necrosis of areas of the liver, hepatitis, diphtheritic inflammation and the formation of ulcers on the intestinal mucosa often occur. Certain strains of viruses can cause predominantly serous-fibrinous peritonitis, inflammation of the lungs and air sacs. Histological examination reveals damage to blood vessels in the acute phase of the disease, and proliferative processes around the reticuloendothelial tissue in chronic cases.

Diagnostics. The diagnosis of Newcastle disease is made taking into account epidemiological, clinical and pathological data with mandatory laboratory tests for isolation and typing of the virus. The virus is isolated from the brain, liver, and spleen of sick and dead birds. From these organs, a suspension is prepared in physiological solution (1:10), to 1 ml of which 3-5 thousand units of penicillin and streptomycin are added to suppress microflora. The suspension is kept for 30 minutes in test tubes to allow large tissue particles to settle; then the supernatant is used to perform a bioassay on 30-60-day-old chickens susceptible to the disease and to infect 9-12-day-old embryos. Embryos are susceptible to infection by various methods of administration of the suspension. The death of embryos occurs after 48-72 hours; The dead are found to have massive pinpoint hemorrhages in various organs.

Chorialantoic fluid is taken from dead embryos, which is examined using the hemagglutination reaction (RHA) and the delayed hemagglutination reaction (RDHA). RZGA has also found wide application in the study of blood serum of recovered birds and testing the strength of novaccination immunity.

To stage RZHA, it is necessary to have a viral antigen (extraembryonic fluids of pseudoplague-infected embryos are often used), physiological solution, test blood serum and a 1% suspension of washed chicken erythrocytes.

First, the hemagglutination reaction is used to determine the highest titer at which the virus causes hemagglutination. For RZGA, it is necessary to dilute the virus 4 times less compared to the highest titer (for example, the highest titer is 1: 640, the working titer of the virus in RZGA is 1: 160).

The test sera in a dose of 0.25 ml, added to test tubes, are successively diluted with equal volumes of physiological solution. 0.25 ml of antigen in working titer is added to the diluted sera, then the liquids are shaken and kept for 30 minutes at room temperature. During this time, the antigen interacts with the antibody, if the latter is in the serum. Subsequently, 0.5 ml of a 1% suspension of chicken erythrocytes is introduced into the mixture of antigen with blood serum and left for 45-60 minutes, after which the results of the reaction are taken into account. Depending on the presence of antibodies and their reaction with the antigen, red blood cells settle to the bottom of the test tube, and in the absence of antibodies, they stick together into lumps. The antihemagglutinin titer is considered to be the highest dilution of blood serum that causes a complete delay in hemagglutination. As a control in the reaction, blood sera containing antibodies and normal sera without antibodies are used.

Differential diagnosis. It is necessary to exclude poultry poisoning, pasteurellosis, infectious laryngotracheitis, chicken typhus, spirochetosis, and classical plague.

In case of poisoning, a certain group of birds that received food containing toxic substances is affected. To exclude poisoning, replace the suspect food and perform a biotest for toxicity by feeding it to a separate group of birds. When opening a dead bird after poisoning, the entire gastrointestinal tract is most often affected; there are no hemorrhages in other organs.

Pasteurellosis is characterized by rapid death of birds; The causative agent of pasteurellosis can be isolated from all internal organs.

With infectious laryngotracheitis in birds, the conjunctiva of the eyes, larynx, and trachea are affected; there are no changes in the gastrointestinal tract. In dead birds, hemorrhages in the larynx and mucohemorrhagic plugs in the trachea are detected.

Prevention has not yet been fully developed. For preventive purposes, all types of live and inactivated vaccines used in poultry farming are used. When comparing the results of immunization in different species of parrots, the most durable and intense immunity is formed in cockatoos and Amazons; the results are somewhat worse in budgies. Immunity develops over 8 days, its activity lasts 2 months, so vaccination of parrots should be carried out in the same way as chickens, twice with a 3-4 week break to achieve the duration of immunity. When a disease appears, it is necessary to type the virus and regularly disinfect the premises.

Psittacosis (ornithosis)

Psittacosis is a viral disease of humans, animals and birds. Virus strains isolated from parrots are commonly called the causative agents of psittacosis; they are especially pathogenic for humans. It has been established that the spread of the virus among birds is significant. Currently, there are 125 species of birds that have been diagnosed with psittacosis.

Etiology and properties of the pathogen. The pathogen belongs to the group psittacosis, lymphogranulomatosis, designated as bedsonia psittacy. Bedsonia strains have varying infectivity and pathology. Some cause severe illness and death, others cause subclinical processes. Infection occurs through aerogenic dust. During the acute stage of the disease, the bird releases the pathogen into the environment with secretions and droppings. Dust particles rising into the air when inhaled enter the lungs of humans and birds. A young bird in a nest can become infected through contact with an adult. A decrease in resistance in poultry (transportation, unhygienic keeping) causes an outbreak of the disease. During mass transportation of imported birds, which is always accompanied by stress, outbreaks and deaths from ornithosis are noted.

If quarantine measures are not observed during the sale of parrots, the disease spreads widely.

The size of the elementary bodies of the virus varies from 250 to 350 mmk. Elementary bodies develop in cytoplasmic inclusions, passing through a series of transitional forms. Cytoplasmic inclusions represent, as it were, a colony of the virus - at the beginning of the cycle from immature, and at the end - from mature elementary bodies.

The viral DNA in the cytoplasm is surrounded by a matrix containing RNA. Under a microscope, RNA and DNA inclusions are visible. Elementary bodies are found in the cytoplasm of cells, and when they are destroyed, they are found outside the cells. They are located in the form of large clusters - “mulberries”, in small groups, chains or pairs. Some strains are toxic and agglutinate the erythrocytes of birds and mammals. Broad-spectrum antibiotics inhibit the virus.

Elementary bodies of psittacosis are retained by finely porous Berkfeld filter suppositories and Seitz plates. Elementary bodies are coccoid in shape and stain well using the Romanovsky-Macchiavell method. Ornithosis easily infects 10-11-day-old chicken embryos, the death of which occurs 2-5 days after infection. The virus is contained in the skin of the embryo and choriallantoic membranes in dilution U-5-U-8.

The causative agent of psittacosis has hemagglutination properties against the red blood cells of mammals and birds; agglutinins accumulate in the blood of recovered animals and birds.

Epizootological data. Under natural conditions, geese, pheasants, and pigeons suffer from psittacosis, but birds from the parrot family are most susceptible. Young birds are more sensitive to infection than adult birds. Artificial infection is achieved by introducing the virus intranasally, intraperitoneally, intracerebrally, intravenously, subcutaneously and orally.

The source of infection is often a sick virus-carrying bird, which releases microorganisms with nasal mucus, when sneezing, coughing, or in feces.

A bird that has had psittacosis usually remains a virus carrier for a long time. In poor conditions, with overcrowding of birds and inadequate feeding, latent infection becomes generalized, accompanied by dissemination of the virus into the external environment. Latently infected adult birds can infect chicks in their nests. The peculiarity of this disease is that it is dangerous for humans; it is characteristic of many species of birds (pigeons, turkeys, sparrows), so there is another name for the disease - psittacosis. This term unites all types of birds, including parrots. The name psittacosis appeared at the end of the last century after a serious illness in people with bronchopneumonia, which arose from contact with imported parrots. Regular epidemics appeared in many countries, so a law was passed according to which all livestock must be destroyed if a disease is suspected. Despite strict regulations, psittacosis could not be eradicated. There is a high possibility of the disease spreading to free-living birds.

The virus is released through excrement and nasal mucus, which contaminate the plumage and surrounding objects.

Poultry under natural conditions becomes infected through airborne droplets when particles of infected material enter.

Clinical symptoms. Psittacosis occurs in parrots with uncharacteristic symptoms; clinical signs, common to all other diseases, often cause deviations in the function of the respiratory tract - rhinitis, shortness of breath, spasms during breathing.

In parrots, the disease occurs in asymptomatic, acute and chronic forms. Clinical signs are not very characteristic: lack of appetite, drowsiness, weakness, profuse diarrhea, leading to exhaustion and death. Under unfavorable conditions for keeping poultry, clinical signs intensify.

In young pigeons, acute infection is often observed during the fledging period. Bilateral conjunctivitis, photophobia, and exudate from the nasal openings occur; pigeons are apathetic, have intestinal upset, and have green droppings. In adult pigeons, in addition to these signs, there is inflammation of the air sacs, as a result of which wheezing can be heard at a distance; paralysis of wings and legs.

Pathological changes are varied and depend on the stage of the process and the virulence of the pathogen. Autopsy of corpses reveals clouding of the walls of the air sacs and deposition of fibrinous exudate, which also covers the liver and heart sac. Peritonitis often occurs in birds.

Small pinpoint necrotic foci are identified in the liver, the spleen is enlarged, and gray-white foci are also visible on the section in the lungs. The intestinal mucosa is catarrhal-hemorrhagically inflamed.

In pigeons, accumulations of exudate and catarrhal enteritis with large foci of necrosis in the pancreas are noticeable in the abdominal cavity.

When opening the accessory cavities, mucus and cheesy masses are found in the nasal cavity.

Considering the danger of human infection, precautions must be taken when sending pathological material to the laboratory for research. The bird's corpse is wrapped in several layers of gauze soaked in a 5° solution of Lysol (phenol, 20% alkali).

Diagnostic tests for ornithosis are carried out in well-equipped veterinary laboratories. Pieces of pathological material are ground in a mortar with quartz sand in a phosphate buffer (pH 7.4) in a ratio of 1:10. The suspension is poured into a test tube and left for 1-2 hours until large particles settle, then 500 units of penicillin and 250 units of streptomycin are added to 1 ml of liquid. White mice are infected with the test liquid intranasally, intracerebrally and intraperitoneally, which die after 3-10 days; 6-day-old chicken embryos are infected into the yolk sac.

Imprint smears are made from the liver, brain, and lungs of white mice, which are fixed with methyl alcohol and stained with Giemsa solution for 4 minutes, 0.25% fuchsin solution in distilled water (with differentiation for 1 s), 0.5% - solution of citric acid and finish staining with a 1% aqueous solution of methylene blue (10-20s). Then the smear is washed with water, dried and examined under an immersion microscope system (X90 lens). Elementary bodies are painted ruby ​​red, and the protoplasm of cells is blue.

To diagnose latent infection, bird blood serum is examined for RSC. To perform RSC, blood from the bird is taken from the heart, the resulting serum is diluted with saline 1:8 and heated for 30 minutes in a water bath at a temperature of 57-58°. Test sera should be stored frozen. In the future, the reaction is carried out using the generally accepted or indirect RSC method. Mass studies of poultry are possible through the use of ornithosis allergen.

Differential diagnosis. The disease must be differentiated from respiratory diseases of birds (respiratory mycoplasmosis, viral sinusitis, waterfowl paratyphoid fever).

Considering that differential diagnostic data is sometimes insufficient and psittacosis can occur in association with respiratory mycoplasmosis, laboratory tests are necessary in all cases of diagnosing psittacosis.

Viral laryngotracheitis

The disease is caused by a virus. There is no consensus on the size of viral particles; it depends on the location - higher in the cytoplasm than in the nucleus of the affected cell.

Electron microscopic examination of the viral particle showed that it consists of a shell and internal contents. Spherical particles of the virus easily pass through Berkefeld filters and Seitz plates.

The infectious laryngotracheitis virus is easily cultivated on 9-12-day-old chick embryos, in which, 3-5 days after infection, grayish-white foci the size of a millet grain appear, covering the chorioallantoic membrane. Sometimes a large nodule is found only at the site of injection of the virus. Allantoic fluid in dead embryos contains fibrin flakes.

A study of the stability of the virus in the external environment showed that tracheal exudate containing the virus, diluted with a 50% glycerol solution in phosphate buffer at a temperature of 37°, retains virulent properties for 7-14 days, at -4° - 217 days.

This disease often affects birds of the gallinaceous order and pheasants, but there are cases of the disease in canaries with a fatal outcome.

Symptoms The bird loses mobility, appetite, breathing is difficult - with noises, sneezing, coughing, secretion leaking from the lateral corner of the eye. Frequent signs of the disease are conjunctivitis and sinusitis.

Pathological signs. In the typical form of the disease, a caseous plug is found in the lumen of the larynx, and muco-hemorrhagic exudate is found throughout the trachea.

In the contents of the trachea, desquamated epithelial tissue and cellular elements are detected. In smears prepared from tracheal epithelial tissue, acidophilic intranuclear inclusion bodies are sometimes found. The bodies appear 12-20 hours after the bird is infected.

Changes in other organs are less typical. When the lumen of the larynx and trachea is blocked, blood stagnates in the parenchymal organs, the heart is enlarged in volume, the intestinal mucosa and cloaca are inflamed.

In a complicated form of infectious laryngotracheitis with respiratory mycoplasmosis, colibacillosis, pasteurellosis, in addition to the listed pathological changes, one can detect inflammation of the air sacs, hemorrhages on the heart, spleen and serous membranes of internal organs,

Diagnosis of infectious laryngotracheitis in birds presents certain difficulties only when the disease occurs without typical clinical symptoms and is caused by weakly virulent strains of viruses. Virological studies, in addition to diagnosing infectious laryngotracheitis, are also necessary when deciding on the use of the vaccine in a dysfunctional household. Diagnosis is based on the isolation and typing of the virus according to accepted guidelines. When making a diagnosis, the affected larynx, trachea, and conjunctival mucosa from a bird are used in the first 7-10 days of the onset of the disease. It has been established that during this period, virus shedding is most active. The diagnostic complex consists of infection of chicken embryos, a bioassay for poultry susceptibility, microscopic and serological studies.

Microscopic changes in infected embryos appear after 2.5-3 days and are most pronounced by the 5-6th day. It has been established that the formation of small nodular lesions on the chorioallantoic membrane is caused by weakly virulent viruses that are difficult to interact with specific serum in the neutralization reaction. During acute outbreaks of the disease, fusion-virulent strains of viruses are released, causing large-focal formations on the choriallanthops membrane. Subsequently, extraembryonic fluids are used for virus typing.

From dead and sick birds, fingerprint smears are prepared from the mucous membranes of the trachea and larynx and stained with Giemsa paint to detect inclusion bodies. The inclusions are polymorphic, stained red and clearly visible against the blue background of the cytoplasm.

In recent years, much work has been done on the use of various serological methods for the diagnosis of infectious laryngotracheitis in birds.

Among the methods that have been used, the neutralization reaction with serums should be mentioned. For this purpose, rabbits and cockerels are hyperimmunized with a suspension of the shell containing the virus.

Viral hepatitis

In zoos, viral hepatitis is common in newly imported birds. Outbreaks of the disease are explained by latent infection, which is activated after transport stress.

The hepatitis virus does not have hemagglutinating properties, is resistant to chloroform, and is easily cultivated on chicken, duck, goose embryos, as well as on cell cultures of renal, hepatic and dermal muscle tissue of duck embryos treated with trypsin. In tissue culture, the virus has a cytopathogenic effect.

Depending on the virulence of the viruses and the age of the embryos, 5-90% of infected embryos may die after 48-96 hours. Long-term passage of the virus on chicken embryos leads to its weakening, while passage on duck embryos restores its virulent properties.

The hepatitis virus is sensitive to high temperatures; heating to 56° causes its death within 60 minutes. The hepatitis virus died 10 minutes after exposure to ultraviolet rays at a distance of 60 cm from the PRK-7 source.

For disinfection, a 1% solution of formaldehyde is used, which causes inactivation of the virus after 3 hours, a 4% hot solution (40-45°) of sodium hydroxide with an exposure of 12 hours, a solution of sodium hypochlorite containing 1.5% active chlorine, 1 2% free alkali, 5% cold solution of iodine monochloride kills the virus within 1 hour.

Clinical signs. The disease is accompanied by poorly expressed clinical signs and sudden death of the bird. Before death, the bird loses its appetite, is in a depressed state, and the abdominal wall is tense as a result of an enlarged liver.

Most of the infected chicks after 72-96 hours, regardless of the method of introducing the virus, became lethargic, refused to feed, in some cases convulsive movements, stretching of limbs, yawning, and narrowing of the palpebral fissure were observed, but these clinical signs gradually disappeared.

Pathological changes. In dead chicks, the most characteristic changes are found in the liver. In most cases, the size of the liver is increased, its color varies from reddish-red to brown. The gallbladder is full; in some cases, the area of ​​the liver adjacent to the gallbladder becomes greenish in color. Throughout the liver there are pinpoint and large focal hemorrhages penetrating into the thickness of the parenchyma; the hemorrhages are clearly distinguished against the background of a discolored liver. In addition to changes in the liver, hemorrhagic ascites, pulmonary leakage, pericarditis and fibrinous-diphtheritic deposits on the wall of the air sac are sometimes detected. In some cases, inflammation of the kidneys and hemorrhagic ascites occur. When opening the cranial cavity, strong injection of the vessels of the meninges and small pinpoint hemorrhages are sometimes noted.

Diagnostics. To make a diagnosis, it is necessary to take into account the suddenness and speed of the onset and spread of infection, the age-related susceptibility of the bird, and characteristic clinical and pathological changes. In the farm where the disease is registered for the first time, it is necessary to conduct laboratory tests to isolate the virus and its typification.

To infect chicken and duck embryos, a simplified method of virus accumulation can be used.

Differential diagnosis of viral hepatitis from similar diseases is based on taking into account the epizootological features of the course of the disease (suddenness and rapidity of spread under normal feeding and housing conditions), the age of the bird, the clinical picture and pathoanatomical changes. It is necessary to exclude paratyphoid fever, viral sinusitis, and poisoning.

To treat and prevent the disease, hyperimmune blood serum is used; there is a vaccine against viral hepatitis, which is used in accordance with the instructions as directed by a veterinarian.

Infectious hepatitis and splenitis owls. The disease is caused by a little-studied virus that leads to the formation of lesions in the liver and spleen that resemble tuberculosis. At autopsy, diphtheroid enteritis, stomatitis, proventriculitis and individual foci of necrosis in the lungs and kidneys are found. In most cases, in contrast to the tuberculosis process, the lesions do not react and do not have a demarcation zone of proliferation. It was possible to experimentally transfer the disease to healthy birds.

Infectious sinusitis (flu)

The disease occurs in the form of catarrhal inflammation of the mucous membranes of the upper respiratory tract.

Etiology and properties of the pathogen. Sinusitis is caused by a virus that freely penetrates bacteria-retaining filters. The size of the viral particle is about 80-120 mm. Its morphological properties are similar to the human influenza A virus. The virus is easily cultivated on 9-10-day chicken and 14-15-day duck embryos using various methods of infection. It was found that after several passages in embryos, the virus significantly increases its virulent properties. The ability of the sinusitis virus to be easily cultivated on various surviving tissues with a pronounced cytopathogenic effect, the ability to agglutinate erythrocytes of poultry, monkeys, guinea pigs, horses, and cattle has been determined.

The blood serum of those who have had sinusitis contains antibodies that delay hemagglutination and neutralize the virus. The stability of the virus in the external environment has been little studied, but by analogy with the human influenza virus, it can be assumed that it is sensitive to ultraviolet rays and is quickly inactivated when heated.

Epizootological data. Viral hepatitis affects all types of exotic birds, especially young birds in the first 30 days of life; in rare cases, infection is observed in older birds. However, the disease is most common in waterfowl in zoos. The extent of spread (up to 90%) of sinusitis depends on predisposing factors, fluctuations in the virulence of the virus and the age-related susceptibility of ducklings.

Symptoms The main clinical signs are: sneezing, constant shaking of the head, when pressing on the cornea of ​​the beak, sticky exudate is released from the nasal openings, which causes blockage of the openings; As a result, patients breathe with their mouths open. In addition to rhinitis, conjunctivitis and keratitis occur. The bird constantly cleans its nose on its perch or paw. The plumage on the head is glued together. Due to the filling of the infraorbital sinuses with fluid, a change in the configuration of the head occurs, sometimes with atrophy of the eyeball. In the acute form of the infection, sudden convulsive attacks may occur, during which the bird dies. In recent years, cases of influenza in the form of gastroenteritis have been reported. The chronic course of the infection is accompanied by growth retardation, and the disease lasts for a period of 5-10 days to 2 months. Viral sinusitis often occurs in association with other infections (paratyphoid fever, pasteurellosis, staphylococcosis, colibacillosis).

Pathological changes. The chick's corpse is emaciated, the feathers in the head area are stained with exudate, the conjunctiva of the eye is hyperemic, and curdled masses are found underneath it. In the paranasal and nasal cavities there is an accumulation of liquid sticky mucous exudate. Often the air sacs become inflamed, the wall of which is thickened and clouded; the liver is enlarged, with congestion.

Diagnostics. To exclude other infectious diseases, it is necessary to culture the nutrient media and perform a bioassay on susceptible ducklings. The filtrate of the emulsion under study is used to infect 10-15-day-old ducklings into the cavity of the facial sinus using a syringe with a thin needle. In addition, chicken embryos can be used to isolate the virus. With a positive bioassay, the above-described clinical signs appear in ducklings after 5-7 days. The bioassay does not give a positive result if the virus has weak virulence.

It is necessary to differentiate viral sinusitis from paratyphoid fever, pastorellosis, aerocystitis, and viral hepatitis.

Paratyphoid fever affects the bird in the first days of life, accompanied by intestinal upset and rapid death. At autopsies of corpses, massive hemorrhages in the internal organs are found. To exclude paratyphoid fever, cultures are done on elective nutrient media. Antibiotics and furazolidone are effective for paratyphoid fever.

With viral hepatitis, massive pinpoint hemorrhages are found in the liver.

Pastrellosis affects growing young and adult birds. It is possible to isolate a virulent culture of pasteurellosis from the internal organs of the dead.



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04.09.2017

Raising chickens on a personal plot is quite a profitable business and can be a good help for feeding a family, because chicken meat and eggs are a tasty, healthy and nutritious product.

When examining chickens, you must first pay attention to the general condition of the birds and how they move their legs, wings and neck. Then you should take a close look at their skin, as well as their breathing, the color of the comb and “earrings”.

If the bird is healthy, it is usually cheerful and active, behaves quite actively and has an excellent appetite. At the same time, their comb and earrings are strong and have a bright red color.

Pseudo or Asian plague (Newcastle disease)

This is a dangerous viral disease that is transmitted by airborne droplets. First of all, the disease affects the internal organs.

Signs and symptoms of the disease are as follows: the bird becomes lethargic, weakened, practically does not move and breathes heavily. The infected chicken's droppings are liquid, and from time to time it turns over and falls on its swollen belly.

The disease is considered incurable.

To prevent the disease, it is necessary to give chickens special vaccinations, try to keep the chicken coop clean and tidy, and change the dry straw bedding more often. Such simple measures significantly reduce the likelihood of an epidemic.

Chicken typhus or pullorosis

The disease is also transmitted by airborne droplets and primarily affects adult birds. The symptoms of the disease are as follows: the chicken drinks a lot of water and develops a saggy, deformed belly. With this disease, the chicken becomes lethargic, weak, her breathing quickens, and the comb becomes flabby and faded.

To prevent the disease, it is necessary to disinfect the chicken coop from time to time and keep the house clean.

The disease can be treated with special antibiotics after an accurate diagnosis has been established.

Paratyphoid or Salmonellosis

It is an extremely dangerous viral disease because it affects the internal organs of birds. The disease is caused by harmful bacteria "Salmonella" and is transmitted by air.

The meat and eggs of sick birds should never be eaten, since the human body can also become infected with this disease.

Symptoms: birds stop feeding, they become lethargic and weak, their breathing is impaired, their eyes are watery and they drink a lot of water.

To prevent the disease, special vaccinations should be carried out and birds should be given drinking water, previously diluted with potassium permanganate.

Streptococcosis

The disease affects the internal organs of birds.

Signs of infection: weakness, lethargy, elevated body temperature, disturbances in the gastrointestinal tract. Cramps and joint inflammation are also possible.

Infected birds must be isolated immediately.

The disease, after establishing an accurate diagnosis, is treated with antibiotics.

Chicken tuberculosis

The disease is transmitted by air and affects the internal organs and lungs of birds.

Symptoms: weakness, loss of activity and mobility, the comb loses its rich red color, becomes pale and flaccid. Earrings become dull and wrinkled.

The disease is extremely dangerous and cannot be treated, so infected birds must be urgently isolated and then eliminated.

In order to prevent the disease, it is necessary to keep the poultry house clean and dry, and from time to time carry out complete disinfection.

Diphtheria (Smallpox)

Small rodents can carry this dangerous disease. The disease is severe and can develop into a chronic disease. It can only be cured at an early stage of infection.

Symptoms include the appearance of red spots on the birds' skin, weakness and lethargy. Infected chickens have difficulty swallowing.

In order to resist infection, young animals are vaccinated. An important factor in prevention is cleanliness in the chicken coop.

Parrot disease or Ornithosis

An extremely dangerous disease that spreads through the air and through droppings. It affects the respiratory and digestive organs and affects the nervous system of birds.

Symptoms of the disease: the birds' breathing becomes heavy, hoarse, mucus flows from the chicken's beak, and the droppings become liquid.

For prevention, add a pinch of potassium permanganate to drinking water intended for chickens, and the birds’ diet must necessarily contain mineral bait and vitamins (fresh greens).

If you get sick, use antibiotics.

Omphalitis

The disease usually appears as a result of insufficient care of birds.

Symptoms of the disease: an inflammatory process in which various formations appear in the navel area, lethargy, and weakness. Infected chickens usually stay in one group.

Antibiotics are used for treatment, and the infected area is treated with a special disinfectant solution.

To prevent the disease, it is necessary to keep the chicken coop clean and dry, for which you need to change the straw bedding as often as possible.

Neurolymphomatosis

With this dangerous disease in chickens, the nervous system and internal organs are primarily affected. In severe cases, blindness and complete paralysis may even occur.

This disease cannot be treated, so infected birds must be isolated and eliminated.

To prevent the disease, early vaccination of young animals is used.

Colinfection or Colisepticemia

This dangerous disease affects most of the internal organs of birds. Spreads through E. coli.

The main cause of the disease is inappropriate living conditions and insufficient care. Infection can also occur due to birds eating low-quality and expired food (chickens do not distinguish suitable food from spoiled and moldy food, so they can easily become poisoned).

Symptoms of the disease: birds lose appetite, breathing changes (becomes uneven and hoarse), and severe thirst appears.

The disease is treated with antibiotics.

Coccidiosis

The cause of the disease is most often low-quality or incomplete food. In birds, the kidneys are primarily affected.

Symptoms: loose stools (possibly with blood), wings become flaccid and droop to the ground, earrings and comb have a faded color.

As a preventive measure, it is necessary to add fish oil, fresh greens (alfalfa, nettle leaves, clover), and mineral supplements to the birds’ diet.

Encephalomyelitis

A dangerous viral disease that is transmitted by air and contact.

In most cases, the disease leads to the death of all infected birds, since the attack primarily occurs on their nervous system.

Symptoms of the disease: loose stools, trembling legs, lethargy and weakness. Complete paralysis is possible.

As preventive measures, birds should be provided with good care and high-quality, nutritious nutrition. The chicken coop must be kept clean. The straw bedding must be dry.

Sinusitis

The infection is transmitted by airborne droplets and primarily affects the respiratory system of birds, therefore the symptoms of the disease are quite easy to determine, since the functioning of the respiratory system in chickens is disrupted, even to the point of convulsions. In this case, liquid may ooze from the beak.

To prevent the disease, vitamins (fresh green food) must be added to the birds’ diet.

Birds infected with the virus are treated with antibiotics.

Laryngotracheitis

This infection is transmitted by airborne droplets and affects the upper respiratory tract of birds.

Symptoms include uneven breathing and wheezing, possible coughing (with blood), and convulsions.

As preventive measures, it is necessary to vaccinate young animals on time and give chickens a drinking solution with the addition of potassium permanganate.

Chicken flu

A very dangerous disease that is transmitted by airborne droplets. The respiratory and gastrointestinal tracts are primarily affected.

The disease is incurable, so all infected birds must be urgently isolated and eliminated immediately.

Symptoms: lethargy, liquid droppings, uneven breathing with wheezing, the comb and earrings lose their rich red color and acquire a blue tint.

Trichomoniasis

A very serious illness. Chickens become infected through food or drinking water.

Symptoms of the disease: lethargy and weakness of birds, the beak is constantly open, and the wings are lowered to the ground.

To prevent disease, birds should be provided with good care and nutritious, high-quality nutrition.

In any case, owners of household plots need to remember that only a qualified doctor can identify the disease and make a correct diagnosis of poultry, therefore, if symptoms of the above diseases are detected, the first step is to isolate the chickens, and then immediately seek help from the nearest veterinary service .

Viral diseases of poultry.

An acute disease that causes mass infections and death of poultry. The ways of spreading the disease are varied: from sick birds, with feed, with droppings, during the transportation of dead poultry meat, by air, through service personnel, and from wild birds.
All types of birds and in any age group are affected by the plague. The disease passes especially quickly, the incubation period lasts from 2 to 18 days, very often 4-5 days.

If the virus is highly virulent, the bird dies before pathological changes appear. As a rule, when suffering from plague, you can see uncharacteristic calmness in poultry, drowsiness, lack of appetite, and loose stools. Farm birds are crowded together, coordination of movements is upset, feathers are ruffled, some birds are on their sides, they are feverish. Body temperatures, as a rule, decrease, and due to the lack of a swallowing reflex, saliva flows from the beak. The fatal outcome of birds reaches 100%.

Sick and dead birds must be killed (burned or buried to great depths, sprinkled with quicklime). An effective means of preventing plague appears to be vaccination, as well as strict hygiene of poultry keeping.

Smallpox. The smallpox virus is particularly persistent in the external environment and can remain active in different objects for up to a year. Very often, smallpox is observed in the autumn and winter. The infection can spread through wounds in the oral cavity, on the comb, earrings, and on the skin. The carriers of the disease are mosquitoes, ticks, lice and other insects.

Smallpox affects all types of poultry and in any age group, but farm poultry in the age group of 5-12 months often gets sick. Smallpox also occurs in wild birds (pigeons, pheasants, partridges). The disease passes especially quickly - from 4 to 14 days.

Accompanied by severe damage to the skin (on the non-feathered part of the body, fingers, paws, crest, earrings, etc.

Skin lesions appear with the appearance of white spots, which then grow together, forming large necrotic lesions. The disease can be in the form of diphtheria, when the tongues and larynx are affected, as a result of which swallowing becomes more difficult. A distinctive sign of smallpox is the presence of scabs on open areas of the skin of farm birds, difficulty swallowing, emaciation, and drowsiness.

If smallpox occurs in a herd, sick birds must be culled and killed; the remaining birds must be given better nutrition and hygiene. The main criterion for prevention seems to be poultry vaccination. Immunity of farm poultry after vaccination - 6-12 months.

Laryngotracheitis. The virus is located in the mucous membrane of the upper respiratory tract and is spread by coughing. The disease spreads through the respiratory tract from a sick bird, through the air, through equipment, water, feed, and also through bedding. Chickens most often get sick with laryngotracheitis. Clinical symptoms appear within 2-3 days; In this case, labored breathing can be observed, the bird stretches its body and head forward, its eyes are closed, it gasps for air for a long time, gurgling and wheezing can be heard, while its head shakes violently. When you cough, blood clots come out, and sometimes foamy discharge appears from the eyes and nostrils.

Laryngotracheitis in poultry can occur in acute and chronic forms. In its acute form, the disease spreads quickly, affecting a significant number of poultry, with mortality reaching up to 70% of the population. To prevent the disease, poultry is vaccinated with a live vaccine. In case of severe damage, the herd must be slaughtered and, after thorough disinfection of the premises, equipment and inventory, replaced with new livestock.

Viral hepatitis- acute disease of ducks. The persistence of the virus is particularly high; it can survive in the external environment for up to 3-5 months. The infection spreads from sick birds, through equipment, through the air, with feed, service personnel, from wild birds (ducks) and other ways. Mainly, hepatitis affects young animals in the age group from 2 to 20 days. Viral hepatitis passes especially quickly (instantly) and causes death in ducklings within an hour. It is difficult to determine the disease in advance; as a rule, the condition of the ducklings is satisfactory, but when moving, the sick ones begin to lag behind the herd, and then fall on their side or back and die after a short attempt to get up. The mortality rate for hepatitis reaches 80% or more.

During the period of bird illness, treatment measures do not have a good effect.

The most important preventive measures are rapid identification of the disease and culling of unhealthy birds at the right time.

Vaccination at the right time can prevent the disease. General preventive measures include increased nutrition of farm poultry, provision of greenery, insolation, and organization of dry and clean bedding.

Currently, there is a high risk of infectious diseases. The use of antibiotics for the purpose of prevention, treatment and as growth stimulants has caused the emergence of highly resistant forms of microorganisms.

A large amount of poultry is concentrated in our region, mainly broiler production (about 15 million heads).

In solving the problems facing the poultry industry, the role of the veterinary service is increasing as never before.

The domestic poultry industry is experiencing a shortage of breeding resources: with today's meat production volumes, more than 500 million imported hatching eggs and about 5 million day-old hybrid meat cross chicks are imported annually.

The causative agents of such infectious diseases as infectious bursal disease, infectious anemia, pseudovirus infection, infectious avian encephalomyelitis, etc. were brought to Russia with imported breeding products. Until 1990, 5 main infectious diseases were recorded in industrial poultry farming (Newcastle disease, chicken infectious bronchitis (IB), infectious laryngotracheitis (ILT), Marek's disease, smallpox), currently there are more than 15 of them.

According to statistical data, mortality from infectious diseases annually amounts to more than 2 million poultry heads, the damage amounts to up to 100 million rubles (data for the Bryansk region).

In the first place are colibacillosis, Marek's disease, Gambor's disease, mycoplasmosis, salmonellosis, IB, etc.

According to the Ministry of Agriculture of Russia, more than 500 unfavorable points for infectious diseases of birds are identified annually. In conditions of market saturation with domestic poultry products, without resolving issues of veterinary welfare, we will not be able to enter foreign markets.

The potential danger of epizootic outbreaks of infectious diseases remains high. Over the past 10-15 years, the pathogenic properties of many pathogens in industrial poultry farming have undergone significant changes, which is caused by a significant increase in the productivity of new crosses and increased contacts with foreign poultry enterprises.

The current level of specific prevention in poultry farming requires at least 10 immunizations of livestock against viral diseases.

Outbreaks of infectious poultry diseases periodically occur in different countries of the world (the most common are Newcastle disease (ND), influenza, IBD, IBD, infectious bursal disease (IBD, Gumboro disease, infectious bursitis of chickens)).

These are highly contagious (contagious) diseases that cause significant economic loss when they occur. Smallpox, tuberculosis, chlamydia, infectious anemia, etc. are recorded less frequently.

Viral diseases are usually sporadic, occurring in isolated cases at individual poultry farms and in the private sector.

In the Bryansk region, no infectious viral diseases of birds have been registered for a number of years.

In Russia, the main place in the structure of infectious diseases is occupied by colibacillosis up to 75%, Marek's disease 7%, salmonellosis 5%, leukemia 1.5%, mycoplasmosis 1.5%. Coccal infections are less common - pseudomonosis, streptococcosis, staphyloccocosis, etc. In the context of large-scale poultry farming, which is typical for Russia, one of the main ways to combat infectious diseases is vaccine prevention. Currently, up to 16 infections (including serovars) are prevented using vaccines. Creation of intense immunity against most of them requires repeated administration.

An important element in organizing anti-epizootic measures, which should be carried out by farm veterinary specialists and district veterinary services, is the vaccination of birds among the population. The epizootic situation in households today leaves much to be desired. No one has ever vaccinated poultry in the private sector before, and only now they are starting to vaccinate poultry against influenza and Newcastle disease.

Planning of anti-epizootic measures must be carried out according to the epizootic situation, first of all in the farm itself, then in the region in which it is located, and also depending on the supplier of breeding products, the planned livestock, and the frequency of vaccine use. The vaccination schedule should be the same both in the breeding farm and in the farm of the buyer of the breeding products. A special approach should be taken specifically for breeding poultry farms. The well-being of the farms that consume their products depends on their well-being.

Today, many are still asking the question: is it necessary to vaccinate birds at all? In this regard, it should be remembered that the costs of biological products account for 3-5% in the structure of product costs. You need to know that with Marek's disease, mortality occurs in up to 20% of the livestock, with 10% culling, Gumboro disease kills up to 30% of the livestock, Newcastle disease - up to 100%, with a decrease in productivity by 100%. Infectious bronchitis leads to mortality, decreased productivity and deterioration in egg quality by 10% for each position. Thanks to the use of high-quality vaccines, mortality from Marek's disease has decreased by 19 times. Effective vaccines against infectious laryngotracheitis have been introduced into production. The incidence of these infections has been reduced to zero.

In our region, existing poultry farms operate in closed mode, and visits by unauthorized persons are prohibited. Plans for anti-epizootic measures are communicated to everyone. The intensity of immunity is monitored according to NB, IBD, IBC, ILT,decreased egg production syndrome-76 (SSY-76) etc. More than 60 thousand studies are carried out per year - the intensity of immunity is within normal limits. About 1 billion poultry of all ages are subject to vaccinations and treatments. All enterprises have created a supply of disinfectants (formalin, caustic soda, ecocide, bleach, dezoline, etc.). Workers are provided with special clothing and shoes, undergo annual medical examinations, and are prohibited from keeping poultry at home. All these measures taken ensure the well-being of infectious diseases of poultry.

Bird flu

Avian influenza is an acute contagious viral disease characterized by general depression, edema, damage to the respiratory and digestive organs, and manifests itself in epizootic outbreaks. Characterized by depression; loss of sensation; cyanosis of visible mucous membranes, comb, earrings; swelling of the subcutaneous tissue, head and neck areas; diarrhea. Death can reach up to 100% of patients. Drowsiness, sneezing, wheezing, shortness of breath, nasal discharge (lacrimation, ruffled plumage, retarded growth and development, possible damage to the nervous system) are observed. In adult birds, egg production decreases. The influenza virus has more than 100 serovars from 15 bird species.

In 2015, avian influenza was not registered among poultry in poultry farms and households in Russia. Among wild birds, it was recorded in the Astrakhan region (pelicans), the Republic of Tyva (terns), and the Trans-Baikal Territory (swans).

Sources of infection are sick birds, the infection is transmitted by airborne droplets, the virus is released in feces, through infected food, water. The source may be migratory birds.

At autopsy, rhinitis, sinusitis, conjunctivitis, pneumonia, enteritis, nephritis, etc. are noted.

Avian influenza should be differentiated from Newcastle disease, infectious bronchitis of chickens, infectious laryngotracheitis, hemophilia, respiratory mycoplasmosis.

The virus is quite stable, direct sunlight disinfects it within 50-55 hours, at t = 55°-60° C in 30-50 minutes, at t = 70° C in 2 minutes. The virus persists in frozen poultry meat for 287 days, in bone marrow for 303 days, in corpses for 30 days, and in feathers for 20 days.

The diagnosis is made based on clinical signs, pathological changes, epizootological data, and laboratory tests. Treatment for avian influenza has not been developed.

For specific prevention, inactivated aluminum hydroxide vaccine against avian influenza type A and liquid inactivated avian influenza vaccine are used. Immunity occurs 3 days after repeated vaccination and lasts up to 6 months.

When avian influenza is detected, quarantine is imposed, health measures are carried out, quarantine is lifted 3 weeks after the final disinfection and completion of all measures of the health plan.

Newcastle disease

Newcastle disease is a highly contagious viral disease of birds, mainly chickens, characterized by pneumonia, encephalitis, multiple pinpoint hemorrhages, and damage to internal organs. Registered on all continents. Causes enormous economic damage and is considered a particularly dangerous infection. First described in 1927.

In 2015, Newcastle disease was registered in 3 constituent entities of the Russian Federation, and a total of 63 birds became ill. The disease was detected in domestic pigeons: in the city of Saratov, 20 pigeons fell ill, in the Ivanovo region, Teikovsky district, village. Morozovo - 42 heads and in Moscow - 1 pigeon fell ill (“Theater of Illusions”). As a result of veterinary-sanitary, preventive and anti-epizootic measures to eliminate the disease, these disadvantaged areas have been improved.

The incubation period lasts from 5 to 15 days. There is depression, weakness, respiratory distress, diarrhea mixed with blood, tremors, paralysis of the paws, wings, the bird may die without any signs, mortality can reach up to 90%, mainly in young animals, old birds rarely die. Egg production decreases and its complete cessation is possible.

When autopsying bird corpses, inflammation of the mucous membranes of the nose, oral cavity, and esophagus is detected; hemorrhages in the form of a belt are visible at the border of the glandular and muscular sections of the stomach. In the small intestine there are foci of necrosis, the spleen is in a state of atrophy. The heart muscle is flabby with pinpoint hemorrhages. In the brain and spinal cord there are phenomena of edema and hyperemia. The virus is quite stable; at t = 56°C it is destroyed in 5 minutes to 6 hours. When frozen, it can be stored for up to 2 years.

Farm poultry are often exposed to pathogenic microorganisms, which result in the development of viral diseases. The most likely causes of infection are:

• placing young birds together with old chickens;
• the sick animal is among healthy birds;
• introduction of infected food into the chicken diet.

Important! If at least one animal shows signs of damage to the body, it must be isolated from the rest of the chickens! This will help avoid mass infection.

Symptoms and treatment features

In order to avoid infection of chickens, it is necessary to promptly identify and begin treatment of sick birds. Let's look at the symptoms of the most common diseases of these farm animals, as well as treatment methods.

Laryngotracheitis

This disease develops in an acute form. Its danger lies in the fact that laryngotracheitis can affect not only chickens, but also other poultry, since it is transmitted by airborne droplets. A sick bird exhibits inflammatory processes on the surface of the larynx and trachea, and conjunctivitis is also pronounced. A sick bird has the following signs characteristic of laryngotracheitis:

1. labored breathing;
2. the chicken stops laying eggs;
3. wheezing is heard during breathing.

The advanced form of laryngotracheitis is practically untreatable. But in the early stages you can get rid of the disease. For this, Tromexin is used in the amount of 2 g per 1 liter of purified water per day. The duration of such treatment should be at least 5 days.

Psittacosis

With the development of this disease, damage to the respiratory tract, gastrointestinal tract, and central nervous system is observed. The following signs are characteristic of ornithosis in chickens:

• inflammation of the eyes, clouding of the iris;
• impaired coordination of movements;
• discharge of mucus from the sinuses;
• intestinal problems, diarrhea;
• weakening of the wings.

In order to cure a bird, you need to use antibacterial drugs such as Ampicillin, Terramycin, Morphocycline, etc. You should also include vitamins A and E in your diet.

Prostagonymosis

This pathology in chickens is characterized by damage to the oviduct, as well as the bursa of Fabricius. The main signs of prostagonymosis are:

1. laying eggs without shells, releasing whites, yolks and dissolved shells;
2. loss of appetite;
3. weakness;
4. abdominal enlargement.

You can rid your animal of this disease using Hexachloroethane or carbon tetrachloride.

Pasteurellosis

Another name for this disease is avian cholera. It can occur in both acute and chronic forms. It is a lesion of the chicken body by a pathogenic microorganism called pasteurella. Characteristic symptoms of an animal infected with pasteurellosis are:

• poor mobility;
• increased body temperature;
• decreased appetite;
• digestive system disorders, diarrhea;
• discharge of mucus from the nose;
• difficulty breathing;
• the comb and earrings change their shade;
• paw joints enlarge.

Pasteurellosis is treated with Sulfamethazine, which should be added to food. It is also necessary to saturate the sick chicken’s body with vitamins.

Sinusitis

This disease is characterized by damage to the upper respiratory tract. A chicken infected with this virus exhibits the following symptoms:

1. discharge of mucus from the eyes and nose;
2. eyelids become very swollen;
3. convulsions;
4. gluing feathers on the head.

An animal can be cured of sinusitis by using antibacterial drugs. The most effective medicine in this case is Terramycin. Also, some chicken breeders use chlortetracycline, which should be added to the feed. The average duration of treatment is about 1 week.

Mycoplasmosis

The causative agent of this disease is a virus called mycoplasma. It affects the upper respiratory tract of chickens.

Most often, older birds are susceptible to mycoplasmosis.

This disease is characterized by the following symptoms:

• difficulty breathing along with coughing or sneezing;
• discharge of mucus from the nose;
• inflammation and redness of the mucous membrane of the eye;
• disruption of the functioning of the gastrointestinal tract.

In order to rid the animal of this disease, oxytetracycline or chlortetracycline should be added to the food for 1 week in the amount of 0.4 g per 1 kg of feed.

Hemophilosis

This disease is characterized by inflammation of the upper respiratory tract. Haemophilus influenzae can be present even in healthy chickens. Activation of the virus occurs as a result of a lack of vitamins or hypothermia of birds. A sick chicken exhibits the following symptoms:

1. severe exhaustion;
2. discharge of watery fluid from the eyes and nose;
3. difficulty breathing with wheezing and an open beak;
4. swelling of the eyelids, which may result in blindness.

The bird also gives off an unpleasant odor after some time.

To cure an animal, you should regularly wash its eyes and sinuses to remove accumulated and dried liquid. After this, carefully inject antibacterial drugs into the nasal openings. In addition, Sulfadimezin, Spopadazine or Etazol must be added to the water that the bird drinks.

Bird flu

This is a disease that affects the gastrointestinal tract and upper respiratory tract. Bird flu is extremely severe. If a sick bird is not isolated in a timely manner, mass destruction can occur very quickly. The following symptoms can be observed in a sick bird:

• increased body temperature;
• severe diarrhea;
• earrings and comb become bluish in color;
• lethargy, weakness;
• difficulty breathing with wheezing.

This disease in chickens cannot be treated. Therefore, after an accurate diagnosis has been established, the sick animal is killed and then burned. This will help avoid infecting other chickens.

Coccidiosis

1. apathetic state;
2. birds spend almost all their time in the roost;
3. exhaustion of the body as a result of loss of appetite;
4. stool excretion becomes frequent and changes color from greenish to bloody;
5. the mucous membranes and comb turn pale;
6. the wings are lowered down, the feathers are ruffled;
7. violation of the musculoskeletal system.

In order to remove coccidia from the chicken’s body, the following medications are added to the water: Furagin, Furazolidone, Sulfadimezin, Norsulfazol or Coccidin. The duration of use of these medications is at least 1 week.

Infectious bronchitis

This disease affects the upper respiratory tract in young animals. As for adult chickens, the functioning of their reproductive activity is disrupted. The number of eggs laid decreases significantly, and after a while disappears completely. The causative agent of infectious bronchitis in chickens is a virus called virion. It is very easily transmitted by airborne droplets or through objects touched by an infected animal.

Infectious bronchitis is characterized by the following symptoms:

• severe cough and difficulty breathing in young chickens;
• discharge of excessive mucus from the nose;
• loss of appetite;
• constant feeling of cold;
• growth and development slows down;
• reduction in the number of eggs laid;
• severe diarrhea.

Attention! After establishing an accurate diagnosis, it is necessary to kill the chicken and then burn it. This is an incurable disease that requires quarantine as a result of the discovery of a sick animal.

The room in which the infected chicken was located should be regularly disinfected using Lugol's solution, aluminum iodide and other products intended for this purpose.

Preventive measures

In order to avoid the development of viral diseases in chickens, the chicken breeder must adhere to the following rules:

1. place young birds separately from adult chickens;
2. a sick chicken must be kept in a separate room, not allowed to have contact with healthy animals until complete recovery;
3. if the chicken is seriously ill, then it is better to get rid of it in order to avoid infection of other animals;
4. regular treatment of the chicken coop with disinfectants, at least once a month;
5. Provide chickens with a balanced diet with added vitamins.

Every farm owner should know the first signs of the most common chicken diseases. This will help you respond to the disease in a timely manner by sending the sick chicken to the veterinarian, as well as provide her with the required assistance. This will help avoid infection of all animals, since such consequences cause serious losses to the chicken breeder.

It should also not be forgotten that The most effective method of preventing viral diseases is animal vaccination. They will protect them from the entry and active development of pathogenic microorganisms. Any purchased chicken must withstand quarantine, being in a separate room from other animals for at least 1 month.