Infectious bursal disease of chickens

Infectiosis Bursitis gallinarum (Gumboro's disease) An acute viral disease of chickens and turkeys, predominantly 2-15 weeks of age, characterized by inflammation of the bursa of Fabricius, joints, intestines and internal hemorrhages.

HISTORY REFERENCE- the disease was first registered in 1956 in Gumboro County (USA). In 1962 Kostrov described Gumboro disease as a disease. Winterfeld and Hitchner (1962) isolated a virus from sick chickens that caused nephrosonephritis in sick broilers. Therefore, sometimes this disease is called nephroso-nephritis. Later, Karnayup (1965) proved that the symptoms of nephrosonephritis are concomitant, the main and permanent changes are found in the bag of Fabricius, and therefore the disease was called infectious bursitis.

The disease is widespread in many countries of America, Europe, Asia, where industrial poultry farming is developed. Serological data show that the infestation of herds ranges from 2 to 100%. And the reason for this is the constant import of poultry.

PATHENGER- RNA-containing virus from the genus Aviovirus of the Reoviredae family (reoviruses). The size of the virion is 70-75 nm. When 9-day-old embryos are infected in the yolk sac, the virus causes their death after 6 days. In addition to growth retardation, it causes

the appearance of edema, necrotizing foci in the liver, which are typical for all viruses of this group. 3 days after the introduction of the virus-containing material into the fibric sac, changes occur that are characteristic of a natural infection. In the culture of chick embryo fibroblasts, the virus causes a cytopathic effect. In a sick bird, virus-neutralizing and precipitating antibodies are formed.

RESISTANCE - the virus is resistant to ether, chloramine and pH 2.0 is sensitive to trypsin. Indoors, the virus persists in the litter for 52 days. At 56°C does not die within an hour. A solution of chloramine (0.5%) inactivates the virus in 10 minutes, formaldehyde (0.5%) in 6 hours.

EPIZOOTOLOGICAL DATA- chickens of all ages are susceptible to the pathogen, but especially broilers aged 2-15 weeks. The most sensitive are 3-6 week old White Leghorn chickens. In adult chickens, the disease is asymptomatic.

The source of the infectious agent is sick chickens that excrete the virus with droppings.

Infectious bursitis is an extremely contagious disease that is easily transmitted when the birds are packed in. Chickens become infected through infected feed, water. A vertical route of transmission of the virus with infected eggs is not excluded. In the transmission of the pathogen, infected care items, equipment, clothing, and personnel play a certain role.

The possibility of spreading the virus through the air has been proven. The reservoir of the pathogen can be flour beetles.

In fresh epizootic foci, the disease proceeds acutely and subacutely, and in stationary foci, it is chronic and asymptomatic. In a number of farms among birds, immunizing subinfection is mainly recorded.

PATHOGENESIS- consists in the defeat of lymphoid tissues, and first of all, the lymphocytes of the Fabricius bag, spleen, caecal glands of the blind processes are destroyed. The virus penetrates through the digestive tract and after 24-48 hours is localized in the fabric bag, affecting B-lymphocytes.

CLINICAL SIGNS- incubation period 1-2 days. It occurs in chickens under the age of 3 weeks in the form of immunosuppression, which is manifested by increased sensitivity to bacterial infections.

It can occur in an acute form in the first 5-7 days after the disease in chickens aged 3 to 6 weeks of age. In case of low resistance of birds, lethality can reach 90%.

One of the first signs is diarrhea, with the release of yellow liquefied litter, or mucous-watery, white, feathering is disturbed.

Then there is a sudden apathy, trembling, signs of damage to the nervous system. The bird soon loses the ability to move, dies in a state of prostration.

The maximum case for 3-4 days from the beginning of the outbreak,

then the mortality rate decreases.

With a course of the disease of 6-8 days, the incidence is 10-20% of the bird, mortality is 1-15%.

Hematological changes are characterized by lymphopenia and erythrocytosis. For 2 days of illness, the total number of leukocytes decreases, on the 5th day it increases and reaches a maximum on the 7th day after infection.

PATHOANATOMICCHANGES- the corpses are well-fed, but the muscles are dehydrated and pale, the goiter is empty, multiple dotted and striped hemorrhages are revealed, especially often under the skin of the thigh; muscles are dark purple.

Bag of Fabricius greatly increased in volume, more than 2 times, contains gelatinous transudate; in the folds of the bag there are fibrinous overlays, and in severe cases - a bloody liquid.

Puffiness of the liver, necrotic foci, atrophy of the spleen are noted. The pancreas is changed, nephrosis. In the final stage of the disease, edema of the kidneys, atrophy of the Fabricius bag appears. Partial striated hemorrhages in the degenerated skeletal muscle of the myocardium, serous membranes, glandular stomach and intestines.

The most typical histological changes are necrosis

lymphoid elements of the Fabricius bag, thymus, spleen, renal degeneration.

DIAGNOSIS- infectious bursitis is a difficult to detect infection that spreads unnoticed, masked by other diseases and physiological disorders, and only in a typical course is it relatively easy to diagnose by clinical and pathological signs. Take into account the high percentage of morbidity, rapid spread and recurrence within 5-7 days. Confirmation of the diagnosis can be the detection of characteristic changes in the fabric bag.

For the final diagnosis, histological studies are carried out and a bioassay is placed by infecting 9-day-old chicken embryos on the chorioallantoic membrane. Embryos die within 3-5 days after infection.

The virus is identified in RN, RDP and ELISA.

DIFFERENTIAL DIAGNOSIS- exclude coccidiosis, poisoning, infectious bronchitis, hemorrhagic syndrome, fungal infections, Newcastle disease.

TREATMENT- not developed.

IMMUNITY- live and inactivated vaccines of the BG strain (Gumboro disease), IBD (infectious bursal disease), Winterfield-2512 are used.

The first vaccine is administered twice at the age of 7-21 days with an interval of 10-14 days by watering. The second time at the age of 110-120 days

once intramuscularly in the region of the pectoral muscle or in the thigh in a volume of 0.5 ml. Immunity occurs 14-21 days after vaccination and lasts up to a year.

In foreign practice, a vaccine from a weakened strain of infectious bursitis virus is used with drinking water and aerosolized. From foreign vaccines, Nobilis Gumboro D78 and 228E can be used. An inactivated vaccine, Nobilis Gumboro inac, has also been developed.

PREVENTION AND CONTROL- carry out general veterinary and sanitary measures to prevent the introduction of the pathogen into the farm.

The young growth of each technological batch is grown in isolation. The state of bird resistance is controlled by targeted feeding and maintenance.

The air entering the house is filtered and disinfected with ultraviolet rays.

With the appearance of infectious bursitis, restrictions are introduced. Sick and suspicious birds are destroyed. Healthy is vaccinated.

The premises are thoroughly disinfected with solutions of caustic soda, bleach (2-3%), and an aerosol of iodine preparations.

If the disease cannot be stopped by general veterinary and sanitary measures, the incubation of eggs is stopped on the farm and additional health measures are taken.

There are no deadlines for lifting the restriction, they are set by veterinarians, since it is difficult to get rid of this disease, due to the rapid development of this disease as a stationary one.

Infectious bursal disease, or Gumboro disease, is a common disease in chickens under four months of age. It manifests itself in the form of diarrhea, damage to the cloacal sac, kidneys, gastrointestinal tract, intramuscular hemorrhages.

What is Gumboro disease in chickens, how to diagnose it and how to protect yourself from it- we propose to talk in this article.

Gumboro disease: chickens and turkeys get sick

Pathogen bursal disease is a virus of the Birnoviridae family that infects lymphoid cells, causing a sharp decrease in the immunity of birds. The virus targets immature β-lymphocytes containing immunoglobulin M. There are two serotypes, roughly speaking, of the species, of this virus: 1 - affects only chickens, 2 - only turkeys. At the same time, the Gumboro chicken virus exists in several variations (subtypes).

Gumboro disease: how they get infected

Gumboro disease is highly contagious: up to 100% of the birds of one group can get sick, while 40-60% die.

Methods of transmission of the causative agent of Gumboro disease:

An infected bird, sparrows, pigeons, etc. can be carriers of the virus.

Feed, in particular feed pests

At the same time, indoors, the avian bursal disease virus can live up to three months, and in dirty rooms - in dust, non-cleaned cages, equipment can be stored for years. Not afraid of sunlight, outdoors shows resistance. In dry litter, it remains active for about two months, on the surface of glass, walls - about one month.

Gumboro disease: how it manifests

Outwardly, the chicken bursal disease virus manifests itself already on the third day after it enters the bird's body. In general, a feature of the acute form of the course of Gumboro disease (subacute course also occurs) is an unexpected, high incidence of poultry (40-100%), an acute peak in mortality (20-40%) and a quick recovery in 4-7 days.

In this case, the Gumboro virus occurs more often at the age of 6-8 weeks, at 3-4 weeks.

It all starts with diarrhea, the litter becomes watery, yellow-white. Chickens look oppressed, huddle together, their feathers are ruffled, around the cloaca they are dirty. The bird does not eat or drink. In this form, the disease manifests itself for 5-7 days, after which Gumboro disease is often complicated by manifestations or colibacillosis.

At autopsy, a cherry-colored cloacal pouch enlarged by 2-3 times is observed. Often, blood clots can be seen in the cavity. There are hemorrhages under the skin on the chest, wings, thighs and in the glandular stomach.

Already on the third day, changes are observed in the Fabrician bursa: due to edema and accumulation of secretions, it increases in size and becomes gray-yellow. On the fourth day of illness, its weight almost doubles, hemorrhages, cloudy contents and necrotic layers are found in it. Sometimes fix intense hemorrhage, covering the entire bursa. On the 7-9th day, atrophy and fibrosis of the bursa is observed.

However, finally put diagnosis of Gumboro disease in chickens possible only on the basis of laboratory data.

Gumboro disease in chickens: prevention, vaccination, outbreak response

In addition to observing the hygienic rules for keeping poultry, chicken owners are required to regularly deal with carriers of the virus - fluff-eating chickens, and monitor the quality of feed.

Chickens are vaccinated with Gumboro chicken virus vaccines in case of a threat of an outbreak. The following vaccines are used on the territory of Ukraine:

Inactivated vaccine from strain BER-93

Virus vaccines from strains UM-93 and VG-93

Gallivac IBD (France)

Inactivated vaccines N.D.V.+I.B.D+I.B. and Quadractin N.D.V.+I.B.D+I.B.+Reo and NECTIVE FORTE (Israel).

There is no cure for Gumboro disease!

At Diagnosis of Gumboro disease in chickens the farm in which the disease is detected is declared unfavorable and restrictions are introduced in accordance with the Instructions. Two months after the removal of the birds from the dysfunctional farm, they are removed. Carry out a complete disinfection in the household. Farms in which IBD has not been observed for one year are considered safe for bursal disease of chickens.

Tatyana Kuzmenko, member of the editorial board of the Sobcorrespondent of the online publication "AtmAgro. Agroindustrial Bulletin"

Gumboro disease (infectious bursitis of chickens, infectious bursal disease)(Bursitis infectiosa galli - Latin, Infestiosus bursae disease - English) is an acute viral disease of chickens, characterized by apathy, anorexia, diarrhea, lesions of the Fabrician bursa, extensive intramuscular hemorrhages, and kidney damage.

Prevalence. For the first time the disease is described in Gamboro USA (A. Cosgrove, 1962). Currently, it is diagnosed in the USA, Mexico, Canada, England, Germany, France and other European countries, Israel, India, Japan, South Africa.

Economic damage significant. Losses consist of the death of up to 10-20% of the livestock, a high percentage of carcass culling as a result of subcutaneous, intramuscular hemorrhages and exhaustion. Large losses are caused by indirect factors: the weakening of the resistance of the livestock to infectious agents, the decrease in the effectiveness of preventive vaccinations, and, consequently, the possible occurrence of new outbreaks of the disease (epizooty) and further restrictions, as well as the negative impact on the productivity and reproduction of poultry during the egg-laying period.

The causative agent of Gumboro disease related to reoviruses. Its taxonomic position remained uncertain for a long time, and in a number of reports it was designated as picorna- or adenovirus. For some time after registration, the disease was called avian nephrosis and was combined with nephrosonephritis caused by infectious bronchitis virus. No antigenic variants of infectious bursitis virus were found.

The causative agent is relatively thermostable (withstands 30 minutes at 70°C), resistant to acids and alkalis in the pH zone from 2 to 12, lipid solvents, in the dried state in contaminated litter lasts up to 120 days. The virus is rapidly destroyed by the action of disinfectants: formalin, iodine derivatives, chloramine.

The virus is well cultivated in chicken embryos of 9-11 days of age, causes their death 4-6 days after infection on the allantoic membrane or in the yolk sac. They note hemorrhages under the skin, in the kidneys, myocardial degeneration, necrosis and greenish staining of the liver, and hepatopathy is often accompanied by similar staining of the yolk and chlorioallantoic fluid.

Chicken embryo cell cultures are highly sensitive to the virus, in which a cytopathogenic effect is manifested in the form of eosinophilic cytoplasmic inclusions and the formation of syncytium. The virus affects only chickens, although, according to some authors, quails and sparrows also get sick (S. Edgar, 1965). Under experimental conditions, white mice are infected intracerebral at the age of 1 - And days or intraperitoneally - 12-14 days. They die in 5-13 days with signs of nervous disorders, encephalitis and myocarditis are noted at autopsy.

epidemiological data. The source of the pathogen is sick chickens. The disease is acute and subacute. Asymptomatic infection is also possible. Virus carrying in convalescents was not noted. The virus spreads rapidly in poultry flocks. It is transmitted when sick and healthy chickens are kept together, through contaminated feed, water, bedding, droppings, in addition, mechanically - by people, other bird species, insects, especially beetles Alphetobius diaperinas (C. Snedeker et al., 1967). The pathogen enters the body through the mucous membranes of the nasal, oral cavities, conjunctiva in natural conditions, apparently, the bird becomes infected by the alimentary route. Chicks 2-15 weeks old are susceptible, most susceptible at 3-5 weeks of age. The disease is not observed in adult hens and chickens up to 14 days of age, even with artificial infection. The incidence is from 20 to 50;%, but can be extremely high (up to 80%), which to a certain extent depends on the breed, the individual state of the organism, the conditions of keeping and feeding. Lethality is from 0.5 to 20%, sometimes up to 50%, depending on the age of the bird (Fig. 16).
The epizootic spread of infectious bursitis is observed mainly in regions with a temperate climate, less often in tropical countries. The disease spreads especially widely in reproductive farms in the presence of birds of different ages. When the disease occurs, the first sign is a massive acute course, later a subacute and more latent course may prevail.

Pathogenesis. The causative agent of infectious bursitis, orally entered the body, is found in the lymphoid cells of the intestine after 4-5 hours. The latter penetrate into the circulating systems, bypassing the Kupffer cells of the liver, and ensure rapid dissemination of the virus. After 11 hours, it begins to multiply in the Fabrician bursa. The resulting viremia is short-lived, lasting up to two days. Then the virus is found in all parenchymal and lymphoid organs, in the highest concentrations in the Fabrician bursa, where it persists for up to 2 weeks (H. Muller, 1979). The pathogen is excreted in the feces.

The defeat of lymphoid tissue is accompanied by a pronounced immunosuppressive effect, which consists in a significant decrease in the number of lymphocytes up to the suppression of all B-dependent immune functions, especially the primary humoral response (antibody formation). The level of serum complement and blood coagulability decrease, the involvement of immune complexes in the pathogenesis is possible (L. Skeeles, 1979). This leads to a loss of effectiveness of immunization of the affected bird against Newcastle, Marek's diseases, infectious bronchitis, an increase in susceptibility to Marek's disease by 3-6 times. A sufficient level of protection against Newcastle disease is achieved only when day-old chicks are immunized or 2-3 weeks before infection with infectious bursitis virus. Against the background of immunosuppression and the absence of lymphocytes, various infections often worsen or occur, for example, colibacillosis, viral hepatitis with inclusions, gangrenous dermatitis, salmonellosis, coccidiosis (Y. Mogeai, N. Debreuil, 1979).

Clinical signs. The incubation period is from 2-3 days to 1-3 weeks (usually 1 week). Initially, the disease is superacute, reaches a maximum in a few days and lasts about 7 days. Clinically manifested by diarrhea (watery whitish discharge), severe apathy, refusal to feed, disheveledness, trembling. These signs are about the same as with coccidiosis. The bird dies on the 4-7th day, often the fallen chickens lie in a characteristic position: with straightened legs and neck.
With a successful outcome, after a week, the symptoms of the disease disappear (M. Krasselt, I. Phillips, 1976).
pathological changes. An autopsy reveals inflammation and hyperplasia of the Fabrician bursa (2 times enlarged), hemorrhagic lesions from petechiae to diffuse hemorrhages in the skin, muscles and connective tissue, nephritis of the "pale kidney" type. These three indicators are enough to make a diagnosis. In addition, there are (10 to 90%) erosions on the gastric mucosa, hepatitis and liver atrophy, nephritis without kidney hypertrophy, atrophied dark or hypertrophied red spleen, serous pericarditis, sacculitis, perihepatitis, peritonitis (P. Montlaur et al. , 1974).

Histological examination reveals necrosis of lymphoid elements, especially in the Fabrician bursa, as well as foci of proliferative inflammation, hemorrhages in the stroma of the follicles, a general picture of purulent and necrotic inflammation with vacuolization in this organ.

Diagnosis and differential diagnosis. The features of the clinical course of the disease and the characteristic curve of the dependence of lethal outcomes on age are important elements of the epidemiological diagnosis of infectious bursitis. A typical pathological and anatomical triad and pathognomonic signs of a lesion of the Fabrician bursa against the background of the course of an epizootic make it possible to diagnose the disease. Under laboratory conditions, the pathogen is isolated from the pathological material of the Fabrician bursa by infection of chicken embryos, cell cultures, healthy chickens and typical lesions are taken into account.

For serological identification of the pathogen, various modifications of the precipitation reaction in the gel and the neutralization reaction in chicken embryos and cell culture are used. Since embryos from immune chickens are resistant to infection due to fapo-ovarian-transferred antibodies, the results of their infection can be used to characterize the well-being of egg supply farms.

Infectious bursitis is differentiated from the following diseases (I. Brugere-Picoux, 1974):
intestinal coccidiosis- clinically manifested approximately the same, excluded by scatological examination;
Newcastle disease- hemorrhagic lesions, characteristic respiratory symptoms, high contagiousness and lethality can be noted, birds of all ages are susceptible;
fatty liver and kidney syndrome- accompanied by hemorrhages and kidney damage, very rarely ends in death, the carcasses of chickens are pale pink;
nephrosonephritis- caused by infectious bronchitis virus, similar in lesions of parenchymal organs, but accompanied by respiratory disorders and does not affect the bursa of Fabricius;
hemorrhagic syndrome of toxic nature- occurs in case of poisoning with sulfamids or mycotoxins, observed in birds of all ages, hemorrhages are concentrated in the visceral organs;
beriberi A- there is atrophy of the Fabrician bursa, the lesions are limited to the epithelium.

Means of specific prevention. Numerous live vaccines with high immunogenicity have been developed abroad. Examples include gumbo-wax (Italy), LZD-228 (Merier, France), Nobilis (Holland). These vaccines are harmless, do not have an immunosuppressive effect, are effective, are stable during storage and passaging, and are convenient for use.

Chickens are vaccinated intraocularly or by drinking the vaccine at one day of age, as well as intramuscularly in groups. older than 12 weeks. The preparations can be used for complex vaccinations in combination with vaccines against Newcastle and Marek's diseases, infectious bronchitis. An inactivated emulsified vaccine is also available. In general, vaccination of chickens ensures the safety and usefulness of lymphoid tissue. Maternal antibodies in high titers are transferred with the egg and protect the offspring during the first four weeks.

Prevention and control measures are to prevent contacts of healthy chickens with sick ones - sources of the infectious agent and factors of transmission of the virus, to limit the contacts of birds of different ages. Affected herds may be c. depending on economic considerations destroyed or kept in isolation under strict restrictions. It is necessary to carry out disinfection, general hygiene measures. In threatened and dysfunctional farms, birds are vaccinated as a preventive measure.

Infectious bursitis (Infectiosis Bursitis gallinarum) is a viral disease in chickens and turkeys, mainly at 4-12 weeks of age, characterized by inflammation of the bursa of Fabricius, joints and intestines.

Historical reference. The disease was first registered in 1956 in Gamboro County (USA). It was described by Kostrov U962) as Gumboro's disease. Winterfeld and Hitchner (1962) isolated a virus from sick chickens that caused nephrosonephritis in sick broilers. Therefore, sometimes this disease is called nephroso-nephritis. Later, Karnayup (1965) proved that the symptoms of nephrosonephritis are concomitant, the main and permanent changes are found in the bag of Fabricius, and therefore the disease was called infectious bursitis. The disease is widespread in many countries of America, Europe, Asia, where industrial poultry farming is developed.

Pathogen- RNA-containing virus from the genus Aviovirus of the reovirus family. The size of the virion is 60-65 nm. When 9-day-old embryos are infected in the yolk sac, the virus causes their death after 6 days. In addition to growth retardation, it causes the appearance of edema, necrotizing foci in the liver, which are typical for all viruses of this group. 3 days after the introduction of the virus-containing material into the fibric sac, changes occur that are characteristic of a natural infection. In the culture of chick embryo fibroblasts, the virus causes a cytopathic effect. In a sick bird, virus-neutralizing and precipitating antibodies are formed.

Sustainability- the virus is resistant to ether, chloramine and pH 2.0 is sensitive to trypsin. Indoors, the virus persists in the litter for 52 days. At 56 C, it does not die within an hour. A solution of chloramine (0.5%) inactivates the virus in 10 minutes, formaldehyde (0.5%) - in 6 hours.

epidemiological data. Chickens of all ages are susceptible to the pathogen, but especially broilers aged 2-11 weeks. In adult chickens, the disease is asymptomatic. The source of the infectious agent is sick chickens that excrete the virus with droppings. Infectious bursitis is an extremely contagious disease that is easily transmitted when the birds are packed. Chickens become infected through infected feed, water. A vertical route of transmission of the virus with infected eggs is not excluded. In the transmission of the pathogen, infected care items, equipment, clothing, and personnel play a certain role. The possibility of spreading the virus through the air has been proven. The reservoir of the pathogen can be black beetles (Alphiotobius diaperinus). In fresh epizootic foci, the disease proceeds acutely and subacutely, and in stationary ones it is chronic and asymptomatic. In a number of farms among birds, immunizing subinfection is mainly recorded.

Pathogenesis. Not studied enough. Highly virulent strains of the virus, introduced into the bursa of Fabricius, after 12 hours lead to the disease and rapid death of the bird with signs of viral septicemia and massive hemorrhages in the subcutaneous fatty tissue.

Course and symptoms. The disease begins with trembling of the body and signs of damage to the nervous system. The bird soon loses the ability to move. In the future, there are ruffled, anorexia, indigestion, mucus-watery, white litter. The bird dies in a state of prostration. Within 4-5 days of the onset of an outbreak, all birds in the flock usually fall ill.

pathological changes. Reveal multiple point and striped hemorrhages, especially often under the skin of the thigh; dark muscles. The bag of Fabricius is greatly enlarged, contains a gelatin-like transudate in volume; in the folds of the bag fibrinous overlays. Puffiness of the liver, necrotic foci, atrophy of the spleen are noted. In the final stage of the disease, edema of the kidneys, atrophy of the Fabricius bag appears. The most typical histological changes are necrosis of the lymphoid elements of the bursa of Fabricius, thymus, spleen, and ileocecal junction.

Diagnosis. On the basis of epizootological data, clinical signs and pathological changes, one can only suspect infectious bursitis of chickens. For the final diagnosis, histological studies are carried out and a bioassay is placed by infecting 9-day-old chicken embryos on the chorioallantoic membrane. Embryos die within 3-5 days after infection. The virus is identified in the RN and RDP.

differential diagnosis. Exclude coccidiosis, poisoning, food encephalomamecia.

Treatment. Not developed.

Immunity. Is being developed. In foreign practice, a vaccine from a weakened strain of infectious bursitis virus is used with drinking water and aerosolized.

Prevention and control measures. Conduct general veterinary and sanitary measures to prevent the introduction of the pathogen into the economy. Young animals of each technological batch are grown in isolation. The state of bird resistance is controlled by targeted feeding and maintenance. The air entering the house is filtered and disinfected with ultraviolet rays. When an infectious bursitis appears, a sick and suspicious bird is destroyed. The premises are thoroughly disinfected with solutions of caustic soda, bleach (2-3%), and an aerosol of iodine preparations. If the disease cannot be stopped by general veterinary and sanitary measures, the incubation of eggs is stopped on the farm and additional health measures are taken.

19.04.2018

Vaccines for the prevention of infectious bronchitis of chickens (IBK) and Gumboro disease are live and inactivated preparations of imported and domestic production. These drugs are available in the form of monovalent as well as polyvalent vaccines that protect birds from 2-4 different infectious diseases. A huge role is played by live vaccines that provide a rapid immune response, including drugs of modern technology.

Vaccination of birds against IB is carried out intraocularly, intranasally, orally and by the spray method (coarse and fine spraying), against Gumboro disease - orally and in ovo.

Infectious bronchitis of chickens

Infectious bronchitis of chickens (IBK) is a highly contagious viral disease, manifested mainly by damage to the respiratory and reproductive organs and kidneys. The disease affects birds of all ages and is especially dangerous for chickens..

Pathogen IB

Caused by an RNA virus with high genetic variability. Mutations of the pathogen are promoted by a number of factors, including the multiplication of the virus in poultry of different ages, mixed infections, joint circulation of the vaccine and field virus in the same herd.

Many strains of chicken infectious bronchitis virus circulate around the world, which makes it difficult to diagnose and prevent this disease. Currently, the greatest danger to the Russian poultry industry is posed by viral strains of the Massachusetts serotype, viruses of serotypes 793B, as well as highly contagious strains of QX and some other pathogens. Several strains circulate simultaneously in poultry farms, but 1–2 major serotypes usually predominate.

Certain serotypes of infectious bronchitis virus can replicate in various tissues of the bird's body.

IBV serotype Massachusetts (Mass) affects mainly the respiratory organs, causing severe respiratory illness. Immunization against viruses of the Massachusetts serotype can be carried out from the first days of life.

Respiratory strains of IBV lead to mortality (mortality rate 15–35%) and create a favorable background for the development of bacterial infections.

The Massachusetts serotype has become widespread throughout the world and was identified in the 1940s in Europe and the USA.

Later it turned out that a number of strains of IBV viruses also affect the excretory organs, while respiratory symptoms can be expressed to varying degrees.

The nephrosonephritis form of IB is characterized by weak and short-term respiratory symptoms followed by depression; the mortality rate of young animals in this case ranges from 25–30% to 70%. Nephropathogenic properties are most pronounced in the QX strain, which came to Europe from Asia and has been circulating in Russia since the early 2000s.

The highly contagious and pathogenic QX strain actively multiplies in the tissues of the respiratory tract, kidneys, ovaries, and lymphoid tissues of the cecum and colon.

In the 90s of the last century, scientists identified the nephropathogenic serotype 793B, which causes high mortality in broilers. Immunization of chickens against this pathogen is usually carried out during the second vaccination. But there are vaccines that can be used from the age of one day.

Serotypes close to Massachusetts, as well as 793B, are the most common strains of IBV viruses in poultry farms in Russia and Europe; the largest number of immunobiological preparations have been developed to protect against these strains. When used together, sufficient cross-protection against the QX strain occurs.

Some strains of the IBV virus (including M41) can reduce the egg production of birds for a long period (causing a drop in productivity parameters from 30 to 89%), degrade the quality of the egg shell and change their color.

As a result, laying hens with normally expressed secondary sexual characteristics, but incapable of laying eggs due to adhesions of the oviducts as a result of salpingo-oophoritis, provoked by the reproduction of the IBV virus in chickens at an early age, are detected in the farms.

Among the new virulent strains that have appeared over the past few years, it is necessary to highlight VAR 2 (Variant 2), circulating in Asia and the Middle East, and more recently in Central Europe. This virus mainly affects the kidneys, respiratory and reproductive organs.

Given the rapidly increasing infectious pressure of the IBV type QX and 793B and new variant strains of type Option 2 in Europe, the Middle East and Russia, Phibro Animal Health Corporation (USA) has developed a live attenuated vaccine TABIK IB VAR 206. It was created on the basis of a field strain Option 2 (IS/1494/06).

The TABIK IB VAR 206 vaccine is manufactured using Phibro's patented TAbic technology (production of live vaccines in the form of sterile water-soluble tablets). This promising development was appreciated by other major vaccine manufacturers.

Boehringer Ingelheim, based on scientific developments in the production of Sanofi effervescent forms under license from Phibro Animal Health, began producing vaccines in the form of effervescent tablets (NEO line). This dosage form significantly reduces storage space and facilitates the work of veterinarians.

During the study of strains of pathogens of infectious bronchitis of chickens, interesting facts were revealed. For example, a combination of some strains of IB pathogens can cause cross-protection against its other strains. For example, immunization with Ma5 strains of the Massachusetts serotype and serotype 793B protect birds from the highly pathogenic QX strain (vaccination occurs with one, revaccination with another strain). The phenomenon of such a synergistic action of vaccines is called the protectotype. It was discovered by Jane Cook, and today it is the main concept in IB immunity.

IBC protection programs

The infectious bronchitis virus is constantly changing. PCR studies on IBV genome sequencing conducted in Russia in the early 2000s showed that about a third of the viruses are previously unstudied and constitute a group of local strains.

Programs to protect chickens from infectious bronchitis include live and inactivated vaccines. The main purpose of vaccination is to develop bird immunity against a wide range of viral agents. Immunization against IB is carried out once or twice (depending on the recommendations of the drug manufacturer and the epizootic situation in the farm). Chickens are vaccinated from the first day of life, regardless of the level of maternal bodies. The third (additional) revaccination against IB should be carried out in both parent and commercial herds before the start of laying (on the 98th–120th day).

Live vaccines are the main tool for protection against IB in parent flocks, broilers and laying hens. They create an early specific defense that develops in the chick within 2 weeks. The main disadvantage of live vaccines is the potential ability of the vaccine strain to revert to the wild type, restore virulence through mutations. Respiratory disease viruses are able to compete for the same receptor sites in the mucous membrane of the upper respiratory tract. Therefore, when using two live vaccines with a different set of strains in the IBV immunization scheme, it is necessary to observe a time interval of at least 14 days.

Inactivated vaccines are used for young laying hens and parent stock (revaccination), cause the production of maternal antibodies. For vaccination with inactivated vaccines to be effective, a live vaccine must first be administered for primary antigen exposure, at least four to five weeks prior to administration of the inactivated vaccine. The content of several heterologous strains in the inactivated vaccine causes the formation of a high level of antibodies to more strains of the IBV virus. Primary vaccination with a live vaccine, revaccination with an inactivated vaccine provides, on average, protection in 95% of cases, while the combination of two inactivated immunobiological preparations - in about 90%.

Choosing the right preparation for immunization will help identify the type of virus circulating in the herd by PCR and others in specialized laboratories.

From the moment they are born, chickens are threatened not only by IB but also by Newcastle disease. A sufficiently large number of drugs have been created for complex protection against these diseases.

Ceva Sante Animale offered a vaccine for vaccinating day old chicks against Newcastle disease and infectious bronchitis (strain H-120) VITABORN L.

A high-quality vaccine against infectious bronchitis of chickens BRONIPRA-1 (strain H-120) for use on the first day of life is offered by the Spanish company Laboratorios HIPRA, S.A. For Newcastle disease-affected areas, the company also has bivalent vaccines HYPRAVIAR-B1/H120 and HYPRAIAR-CLONE/H120, which have been successfully applied from the first day of life using the large-drop spray method.

Monovaccines for the prevention of infectious bronchitis in chickens

Vaccine	Description	The strain and serotype of the pathogen	Manufacturer
AVIVAC-IBK	live dry	A/91 serotype 793/B	NPP AVIVAC, Russia
AVIVAC-IBK	live dry	H-120 serotype Massachusetts	NPP AVIVAC, Russia
Bioral H120 NEO	live tablet	H120 serotype Massachusetts	Boehringer Ingelheim, France
BRONIPRA-1	live dry	H-120 serotype Massachusetts
Vaccine against infectious bronchitis of chickens from a variant strain PB-07 live dry	live dry	strain PB-07
	live dry	H-120 serotype Massachusetts	FGBI ARRIAH, Russia
Vaccine against infectious bronchitis of chickens from strain H-120 live dry	live dry	H-120 serotype Massachusetts	JSC "Pokrovsky Plant of Biopreparations"
Vaccine against infectious bronchitis of chickens polystrain inactivated emulsified	inactivated emulsified	Taganrog serotype 793/B + strain Kaluga + H-52 serotype Massachusetts	FGBI ARRIAH, Russia
Live dry virus vaccine against infectious bronchitis of chickens (IBK) from strains H-120, PB-07	live dry	H-120 serotype Massachusetts, variant strains PB-07	Kronvet, Russia
Wolvak IB Mass MLV	live dry	modified Massachusetts serotype virus	Boehringer Ingelheim, Germany
Gallyvac IB 88	live lyophilized	CR88121 serotype 793B	Boehringer Ingelheim, France
Gallyvac IB 88 NEO	live tablet	CR88121 serotype 793B	Boehringer Ingelheim, France
Gallimun 793B	dry inactivated	variant strains of serotype 793B	Boehringer Ingelheim, France
	live dry	H-120 serotype Massachusetts	FKP "Shchelkovsky Biokombinat", Russia
Nobilis IB 4/91	live dry	4/91 serotype 793B	Intervet/MSD, The Netherlands
Nobilis IB Ma5	live dry	Ma5 serotype Massachusetts	Intervet International/MSD, The Netherlands
Pulvak IB H120	live dry	H-120 serotype Massachusetts	Zoetis Inc., USA
Pulvak IB QX	live dry	serotype QX (L1148)	Zoetis Inc., USA
Pulvak IB Primer	live dry	H-120 serotype Massachusetts + variant strains D274	Zoetis Inc., USA
Sevak Ayberd	live dry	1/96 serotype 793B	Ceva Sante Animal, France
Sevak MASS L	live dry	B-48 serotype Massachusetts	Ceva Sante Animal, France
Sevak BRON 120 L	live dry	H-120 serotype Massachusetts	Ceva Sante Animal, France
TABIK H-120	live dry tablet	H-120 serotype Massachusetts	Phibro Animal Health, Israel
TABIK IB Var	live dry tablet	233A serotype 793B	Phibro Animal Health, Israel
TABIK IBVAR2-06	live tablet		Phibro Animal Health, Israel
HatchPack IB H120	live frozen	H-120 serotype Massachusetts	Boehringer Ingelheim, France

Immunization of chickens against IB can also be carried out polyvalent drugs:

– produced by Ceva Sante Animale: Sevak Megamun ND-IB-EDS-SHS K, SEVAK NB L, SEVAK VITABRON L;

– produced by Intervet/MSD: Nobilis Ma5 + Clone 30, Nobilis IBmulti + ND + EDS, Nobilis IBm + ND + EDS, Nobilis RT + IBmulti + G + ND;

– manufactured by Laboratorios HIPRA, S.A: HIPRAVIAR-TRT4, HIPRAVIAR-CLONE/H120, HIPRAVIAR-B1/H120, AVISAN MULTI;

- manufactured by Boehringer Ingelheim: Volvac ND + IB + EDS KV, Gallimun 303, Gallimun 407;

– manufactured by Abic Biological Laboratories Ltd (a division of Phibro Animal Health): VH + H120, Quadractin VP 2 , SSS + NB + IB;

– produced by Zoetis: Provak 4, Pulvak Aero;

– produced by AVIVAC: AVIVAC-IBK + NB, AVIVAC NB + IBK + IBB + SSYA + REO

and some other vaccines.

Gumboro disease

Gumboro disease, or infectious bursal disease (GD, IBD) is a highly contagious viral disease of chickens 2–20 weeks of age, accompanied by damage to the bursa of Fabricius, to a lesser extent - other lymphoid organs and kidneys, the presence of hemorrhages in the muscles of the thigh, chest, wing and in mucous membrane of the glandular stomach. Along with Marek's disease, IBD is a major immunosuppressive disease in poultry.

IBB - a blow to the poultry industry

The Gumboro virus was first discovered in the 1950s in the United States. Today it circulates in all countries of the world with developed poultry farming and causes great economic damage. Periodically in Europe, outbreaks of highly virulent strains of IBD are recorded, leading to mortality from 10 to 30% of young birds.

The causative agent of the disease is stable in the external environment. In litter, water, feed, it does not lose its infectious properties for 56 days, on poultry farm equipment - up to 122 days or more.

Infectious bursal disease can occur both in acute and subclinical form, accompanied by a lag in the growth and development of chickens, suppression of their immunity, susceptibility to viral, bacterial and other diseases.

The subclinical form of the disease, no less than its acute course, causes significant damage to farms. According to Intervet/MSD, the returns from growing broilers in Gumboro disease-free flocks are, on average, one-third higher than those earned from growing birds with subclinical disease.

It is possible to detect the IBD virus by ELISA, PCR, diffuse precipitation reaction on agar gel and some other methods.

Modern methods of protection

Live vaccines IBB are used to vaccinate healthy broiler chickens and rearing young meat and egg breeds. They provide the rapid formation of immunity. The frequency of vaccination is double or single, depending on the recommendation of the manufacturer of a particular drug. Live vaccines against Gumboro disease are given 6 to 8 weeks before the administration of the inactivated vaccine. The disadvantages of live IBD vaccines include immunosuppression, which provokes an insufficient response to vaccination and increases the likelihood of developing other infectious and parasitic diseases.

The range of industrial strains is quite extensive. For example, vaccines containing a moderately attenuated strain of the Gamboro disease virus are available, such as AviPro Presize (Elanco) - LC-75, Nobilis Gamboro 228E (Intervet / MSD) - strain 228E, HYPRAGAMBORO-GM97 (Laboratorios HIPRA, S.A.). To protect poultry, an intermediate vaccine strain Winterfield 2512 is used, which is part of the imported and domestic immunobiological preparations Sevak TRANSMUNE (Ceva Sante Animale), KHIPRAGAMBORO-SN / 80 (Laboratorios HIPRA, S.A.), AVIVAC-IBB ​​(SPE "AVIVAC"). There are vaccines containing weakly attenuated (hot) strains, for example, TABIK MB (Phibro Animal Health) - MB strain, etc.

Prevention of Gumboro disease is hampered by the presence of maternal heterogeneous antibodies in chickens. With a high level of maternal antibodies, the vaccine virus is quickly recognized and neutralized by the cells of the chick's immune system.

Thanks to a special innovative technology, Ceva Sante Animale specialists created immunocomplex vaccine Sevak TRANSMUNE, which allows solving the problem of preventing Gamboro disease in chickens with a heterogeneous level of maternal antibodies. The vaccine is administered once to chicken embryos at the age of 18.5 days by the method in ovo or day old broiler chickens subcutaneously. After the vaccine virus replicates, the immune response culminates in the formation of protective antibodies against Gumboro disease.

At the origins of the creation of immunocomplex vaccines was Embrex, owned by Zoetis, a manufacturer of equipment for in ovo vaccination.

There are other similar drugs. Based on strain 2512 of the Gamboro virus and antibodies from hyperimmune blood serum of SPF chickens, Zoetis has developed the drug Bursaplex.

Cloned live vaccine HIPRAGAMBORO-CH/80 has a minimal immunosuppressive effect on the bird's body and has a high antigenic activity and immunogenicity. Designed for use in prosperous, disadvantaged and threatened breeding and commercial poultry farms. Contains a culture of fibroblasts of SPF chicken embryos infected with the cloned CH/80 virus of the Gumboro disease strain Winterfield 2512. Chickens are vaccinated twice starting from the age of 7 days.

Along with immune complex preparations, recombinant vaccines do not require monitoring of maternal antibody levels.

Recombinant live vaccine Vaxitec HVT + IBD is manufactured by leading health expert Boehringer Ingelheim. The V2 gene, cloned from the Faragher 52/70 strain, is inserted into the vaccine, and the turkey herpes virus serves as a vector. The drug is administered to chickens of meat and egg breeds once at a daily age or in ovo and provides protection against both classical and variant and highly virulent strains.

Thanks to ongoing developments in the field of recombinant and immunocomplex vaccines, it is possible to take a step towards the eradication of a number of animal viruses.

But writing off classic drugs is still premature. A properly selected traditional live vaccine based on an intermediate strain provides the necessary level of protection. This is evidenced by a number of studies, including those of Phibro Animal Health specialists.

Domestic manufacturers offer vaccines with a wide range of topical vaccine strains. The preparations are produced on modern equipment and meet international standards. A great contribution to the protection of poultry health and ensuring food security in Russia is made by the vaccines of NPP AVIVAC, FKP Schelkovo Biokombinat and FGBI ARRIAH.

In 2018, a new drug was registered by the FGBU “Federal Center for Animal Health” (“ARRIAH”). The basis of the live dry vaccine Gamboromiks is a combination of strains of Gumboro disease Winterfield 2512 and GD, positioned as "intermediate" and "hot" variants of the virus.

Monovalent vaccines against Gumboro disease

Vaccine	Dosage form	Strain	Manufacturer
AviPro Presize	live dry		Elanco, Germany
AVIVAC-IBB	live dry		NPP AVIVAC, Russia
AVIVAC-IBB	live dry		NPP AVIVAC, Russia
AVIVAC-IBB	live dry	Winterfield 2512	NPP AVIVAC, Russia
AVIVAC-IBB	liquid inactivated		NPP AVIVAC, Russia
Bursaplex	live dry	2512 + antibodies of hyperimmune blood serum of SPF-chickens	Zoetis Inc., USA
Bursin Plus	live dry	Lukert, protein stabilizer H	Zoetis Inc., USA
Vaccine against infectious bursal disease from the strain "VNIVIP" live dry	live dry		FKP "Shchelkovsky Biokombinat", Russia
Virus vaccine against infectious bursal disease from strain "BG"	live dry		FGBI ARRIAH, Russia
Virus vaccine against infectious bursal disease from the strain "Winterfield 2512"	live dry	Winterfield 2512	FGBI ARRIAH, Russia
Gamboromix	virus vaccine against infectious bursal disease live dry	Winterfield and BG	FGBI ARRIAH, Russia
Nobilis Gumboro D78	live dry		Intervet/MSD, The Netherlands
Nobilis Gamboro 228E	live dry		Intervet/MSD, The Netherlands
Pulvak Bursa F	live dry		Zoetis Inc., USA
	dry live		Phibro Animal Health, Israel
SEVAK IBD L	live dry	Winterfield 2515, G-61	Ceva Sante Animal, France
SEVAK GUMBO L	live dry		Ceva Sante Animal, France
HIPRAGAMBORO-SN/80	live dry	Winterfield 2512, CH/80 clone	Laboratorios HIPRA, S.A., Spain
HIPRAGAMBORO-GM97	live dry		Laboratorios HIPRA, S.A., Spain
Transmoon IBD	dry live	Winterfield 2515 + complex of immunoglobulins from hyperimmune blood serum of SPF-chickens	Ceva Sante Animal, France

Inactivated vaccines against IBD are used as part of polyvalent preparations for parent stock. They ensure the creation of the proper level of maternal antibodies in chickens.

Polyvalent vaccines against Gumboro disease are presented:

– Nobilis RT + IBmulti + G + ND (Intervet/MSD);

– HIPRAVIAR-TRT4 (Laboratorios HIPRA, S.A.);

– Sevak ND-IB-IBD-EDS K (Ceva Sante Animale);

– Provak 4 (Zoetis Inc.);

– Vaxitec HVT + IBD, Bursa Guard REO (Boehringer Ingelheim);

– Quadractin VP 2 (Abic Biological Laboratories Ltd, a division of Phibro Animal Health)

and some other vaccines, including those manufactured in Russia.

Number of impressions: 2243
Author: V. Lavrenova, Marketing Specialist, Agricultural Technologies Publishing House