The use of preparations based on cephalosporins in the treatment of chronic mastitis in cows

ORBITOBACTERIOSIS IS A SERIOUS PROBLEM IN THE POULTRY

I.K. Avdosyeva, Ph.D., S.A. Ponomareva

State Scientific-Research Control Institute of Veterinary Medicinal Products and Feed Additives

Respiratory diseases are one of the main problems in the poultry. Оrnitobacteriosis (ORT) takes pride of place among them.

The causative pathogen was isolated for the first time in 1991 in broilers in the South Africa. Later on it was confirmed in the Netherlands, where the bacterium, which had not been known before, was named ORT. ORT was found later in the archive cultures of the 1980s in many countries of the world, however in that time the role of this bacterium in infection pathology was seriously unevaluated.

Оrnitobacteriosis is an infection disease of turkeys and chickens, which is characterized by disorder of infraorbital sinuses, trachea, air sacks and pathogenic path of aerosacculitis, pleuritis and lobar or multilobar pneumonitis.

The causative pathogens – Ornithobacterium rhinotracheale – are gram-negative spatulas that do not form spores. Nowadays 18 serotypes (from A to L) are known.

The source of infection is sick and recovered birds. The causative pathogen is transferred both horizontally and vertically. Bad management, improper environment, high density, violations of the sanitary and veterinary conditions, different infection diseases accompanying the respiratory path disorders facilitate the infection path.

Chickens, turkeys, pheasants, quails, ducks, gooses, doves, guinea fowls and ostriches are susceptible to ORT. Mostly often poultry meat, namely turkeys and broiler chickens, suffer from ORT.

ORT causes the disease by self-active pathogens and also if effected by other agents, like by the Newcastle disease viruses, rhinotracheitis and bacteria (Bordetella avium and E.coli).

Birds previously infected with Newcastle disease viruses being infected with ornitobacteria bear the symptoms of aerosaccultitis and pneumonia clearly expressed in 5-7 days after infection and practically being absent in 2-3 weeks.

Solely poultry infection with ortinobacteria is not accompanied with the respiratory path disorders, although it induces serological reaction close to the one, observed at double infection.

The clinical signs level depends on the ORT strain virulence and is increased at microclimatic violations.

Diagnosis of ornitobacteriosis is made based upon epizootological data, clinical signs, pathoanatomical changes, serological (EIA) and bacteriological tests, as well as the positive biological tests.

Clinical signs:  sneezing, coughing, breath stress due to pneumonia and formation of air bubbles, eyes moistening, swelling of the infraorbital sinuses (in age from 6 up to12-20 weeks), decrease of performance, less weight gain, reduced egg production and egg quality, tenontitis, shin muscle inflammation combined with paw arthritis, that are observed after about 10-14 days after the first symptoms in the respiratory system.

Broilers are suddenly sick at age of 3-5 weeks, mortality level depends on strain (10-20%); turkeys are sick at age of 2-8 weeks; the most severe lesions are observed at the age of over 14 weeks; clinical course is acute, mortality is very high (15-50%). Increase of mortality and decrease of egg production is observed in breeders. At the same time the fertilization and hatchability are not decreased. Significant decrease of egg production and low eggshell quality is observed at layers.

Pathoanatomical changes: mostly unilateral fibrinopurulent inflammation, presence of air bubbles in the abdominal sacks, inflammation of pericardial sac, which is filled with semi-liquid creamy-yellow fibrin, paw arthritis (Fig. 1, 2, 3, 4).

The disease under its main clinical and pathoanatomical changes is mostly characterised as one caused by bacterium of Escherichia coli, Bordetella avium, Pasteurella multocida; by microplasmas: Mycoplasma galisepticum, Mycoplasma meleagridis, Mycoplasma iowa, Mycoplasma synowie; by viruses of TRT, ND and HE, so it is necessary to consider that the clinical course is accompanied in combination of the above said pathogens.

Fig 1. Fibrinopurulent inflammation

Fig 2. Presence of air bubbles in the abdominal sacks

Fig. 3 Fibrous plaques in the abdominal sacks

Fig. 4 Fibrinous peritonitis with fibrous plaques in the abdominal sacks

So, for the effective therapy:

·        it is necessary as soon as possible to define sensibility of ORT bacteria to the antibiotics;

·        to consider that sensibility of some serotypes to medicines rapidly changes;

·        to consider in the therapy practice the accompanying diseases.

Definition of sensibility of the defined ornitobacteriosis races to different antibiotics is provided in Figure 5.

Fig. 5. Sensitivity ratio of ORT strains isolated from respiratory path and paw of turkeys (France) to antibiotics 

The highest percentage of ORT strains isolated in turkeys was sensitive to thylosin and thymulin, while the strains were resistant to erythromycin and flumekvin.

For the prevention and treatment of ORT one is to use:

·        tetracycline;

·        macrolides (tilmicosin, thyamulin);

·        semi-syntactical penicillin (amoxicillin, amoxiclav).   

In Europe tilmicosin in dosage of 10-20 mg per 1 gram of live weight is considered to be the most perspective one.   

List of medicines registered in Ukraine to be used for ORT therapy

(as of 1st May 2015)

TIAMUCOL, TILMICOVET

For broiler breeders there has been developed and is widely used nowadays the inactivated vaccine. However, only rational use of antibiotics allows to eliminate infection both in the broiler breeders and broilers.

Numerous attempts to develop vaccines for the specific immunological prophylaxis performance are being conducted at the moment, but up to now they do not give positive results in turkey meat first of all due to the circulation of 18 serotypes.

Vaccines available in the market include maximum 3 serotypes and are used mainly in broiler breeders:

Ornitil Triple is an inactivated emulsified vaccine developed against ornitobacteriosis of chickens and turkeys should be used in age of 4-6 weeks (Abik, Israel);

Nobivac ORT inac. (Intervet, the Netherlands).

The economic effect of vaccination is doubtful since:

·        vaccination of breeders can defend the breeds while the immunity is not   preserved until slaughtering;

·        in the USA vaccination is made with live vaccine, in Europe, where the usage of live vaccines is prohibited, the broilers are treated with inactivated vaccine twice;

·        only good management, biological safety and in-time anti-bacteriological therapy will effectively defend the birds from ornitobacteriosis.

For prevention of respiratory diseases (micoplasmosys, rhinotracheitis, ornitobacteriosis, pheumomycosis) one should:

·        to conduct air sanitation at birds’ presence with such disinfectors as ecocide C, 1% delegol, vircon, 1.5% brovadez, Javel Clade, Srerillium AB, etc.;

·        to perform iodine sublimation (as prescribed), iodine + alluminium, turpentine + bleaching powder; Dixam, Clinosan, Amosan, Desosan Vigor.

For successful prevention of ornitobacteriosis it is necessary to conduct the whole complex of veterinary and sanitary measures, as well as to ensure permanent serological monitoring of blood serum in EIA to detect the specific antisubstances in order to perform effective antibacteriological therapy, including vaccination of the breeders of meat crosses of chickens and turkeys.