I. Summary

Since October 1987, we have observed each fall, apart from the migration of a specie of starlings from north to south of the peninsula, the introduction of certain respiratory diseases in chickens.

This infectious disease, very similar to poultry infectious Bronchitis, is caused due a haemolytic germ from the gender of Haemophillus, having been isolated both in chickens and starlings.

The effect of this infectious disease is very similar to Coryza disease in layers, although the first one has more pathogenic aggressiveness, causing up to 30-40% of casualties if a suitable treatment is not administrated.

It is known the presence of diseases caused by haemolytic germs in poultry such as E. coli, Pasteurella, Haemophillus and Ornithobacterium rhinotracheale, as well as its transmission through bloodsucking factors (Goniocotes gigas) and other animals. This investigation pretends to update the poultry pathology produced by haemolytic germs by supplying new information about its transmission through wild birds.

II.Vector-borne diseases: insects and birds

It is described the transmission of diseases through bloodsucking parasites as vector-borne diseases:

Goinocotes gigas is an external parasite which belongs to the gender of Goinocotes. It is a chewer louse, commonly known as the “large louse of chicken”.

Males are usually 3.3mm long and females about 4mm. They are greyish-white and yellowish, with black tongue-shaped spots only on the edge. Its head is round with hairs arranged radially, and the abdomen is very broad, oval-spheroid.

Lice have a 3 week life cycle, laying eggs in skin or feathers, hatching the larva at 5-8 days and becoming an adult after three changes. They have great mobility and chewing capacity and feed by sucking blood and biting epidermis or bleeding quill of young feathers.

The transmission of these lice usually is by contact among birds. Men and other mammals can host them, but only temporarily as louse is not its main host.

It is usual the transmission of diseases through wild birds which act as carriers.

– Gustafson and Moses in 1935 (cited by Zarzuelo and Gaiano in 1969) showed that 35 wild bird species were receptive to the virus of Newcastle and 16 of them could get infected under natural conditions.

-Brandy and Moses

– Brandly and Moses identified natural outbreaks with clinical disease in chickens, turkeys, guinea fowl, ducks, geese, pigeons, pheasants, partridges, crows and sparrows.

– Kaschula showed how pigeons could act as unapparent carriers of Newcastle disease.

-Zarzuelo and Galiano in 1969 demonstrated the importance of the transmission of viral diseases (in particular the poultry pseudopeste) through wild birds in the Iberian Peninsula. In particular, their studies were based on sparrows, quail, goldfinches and greenfinches.

-Borrell, J. (1990) linked the starling (Sturnus vulgaris) with the production of a respiratory-haemolytic disease in chickens. The starling, which belongs to the Family of Sturnidae, is a migratory bird whose migration coincides with the epidemiology of the disease. In October they fly in large flocks, migrating to Southern Europe or Northern Africa, looking for warmer areas to spend winter.

III.- Haemolytic bacterial diseases in poultry pathology

1.-Poultry cĂłlera (Pasteurella multocida)

Pasteurella is a genus of Gram-negative responsible for the poultry cholera disease, widely spread, which affects domestic and wild birds.

Turkeys and water fowls are more susceptible to Pasteurella than chickens, and among chickens, the older the more susceptible.

It is usually presented as a sudden septicemia, with high mortality and morbidity, although it can also be presented in a chronic and asymptomatic way.

In the acute case, this disease presents the following symptoms: dead birds, fever, depression, anorexia, mucous discharge, ruffled feathers, diarrhea and respiratory rate increase. These injuries are related to vascular disorders: hyperaemia, especially in blood vessels of abdominal viscera; petechial and equimotic haemorrhages in subserosal and subpericardio.The liver presents multiple small necrotic focuses and in turkeys is common the pneumonia.

Chronical injuries are usually related to local infections: swelling due to accumulation of exudate fibrinopurulent in sternal bags, joints and soles of the feet.

It can exist torticollis (infection of meninges, middle ear or cranial bones), exudative conjunctivitis and pharyngitis.

The first diagnosis can be made by signs and injuries although the definitive one will require isolation and identification of Pasteurella. The prevention will include an adequate handling, and the use of bacterinas (with high efficacy). The infectious treatment will include penicillin, tetraciclinas or sulfamids.

Prevention will include appropriate management and use of bacterins (with high efficiency). The anti-infective therapy will include penicillins, tetracyclines or sulfonamides..

2.- Haemolytic Colibacilosis (E. Coli)

Escherichia coli is a Gram-negative bacteria, very important for its pathogeny and world distribution. There are many strains and serovars with different virulence, being the most common in aviculture the serovars belonging to groups O1, O2, O36 and O87.

Its natural transmission is by oral route, although it also can be transmitted by air or contaminated eggs.

Compared with mammals, exotoxins are less common in aviculture. There mainly exist enterotoxins and endotoxins which produce vasculitis followed by septicaemia and lethal shock. The incubation period varies within 24-48 hours. Clinical signs of the disease vary depending on the place of the infection (digestive, reproductive, and respiratory…..).

The common injuries which can be found are the following: haemorrhages in large muscular mass and in fat of the cardiac base where petequiae can be found, which permits to distinguish poultry haemolytic Colibacilosis from non haemolytic.

Poultry haemolytic colibacilosis can be encouraged by the presence of mycotoxins in animal feed, as the ingestion of aflatoxins produces hemorrhagic injuries.

The diagnosis of poultry haemolytic colibacilosis is realized by obtaining pure cultures of E.Coli in common and specific media, from blood, injuries and parenchymal organs. The treatment consists of administration of anti-infective, and the symptomatically use of moisturizing and anti-inflammatory analgesic-antipyretic (we have used antipyrine obtaining excellent results).

As anti-infective, the use of amoxicillin with perfloxacine is indicated due its great results. Prevention of the disease must be based on proper hygiene and vaccination of birds.

3.- Rhinotraqueale Ornithobacterium

Gram-negative bacillus described by Vandamme in 1994 and isolated from respiratory tract in ducks, chickens, partridges and jays by Charlton and in 1993 by Hafez in chickens and ducks.

Clinically it has been linked to weakness, dyspnea, arthritis, growth retardation, expectoration of bleeding mucus, bronchopneumonia serophibrinous with blood in the trachea and bronchi at autopsy, and inflammation fibrinous in thoracic air sacs.

Its diagnosis will be performed by isolation in blood agar under microaerophilic conditions samples of heart, spleen and liver. It also presents slow growth.

Sucrose does not ferment, although glucose, mannose, fructose, galactose, lactulose and maltose do.

Its differential diagnosis will be mainly with Pasteurella. It is believed that many cases of rhinotraqueale Ornithobacterium have been poorly attributed to Pasteurella anatipestifer.

The treatment of choice in addition to symptomatic is the administration of anti-infectives such as amoxicillin, penicillin G and Enrofloxacin.

4.- Poultry Coryza (Haemophillus paragallinarum)

Haemophillus paragallinarum was described for the first time as Bacillus hemoglobinophilus coryzae gallinarum in 1931 (De Blieck). In 1934 (Eliot and Lewis) changed it to the present name as it was not binomial.

It is a facultative anaerobic, with better growth if CO2 is added; requiring in its growth V factor but not X, and requires a medium with 1% sodium clorurote. It does not produce indole or hydrogen sulphide. It regularly ferments glucose and mannose, galactose, fructose, maltose, sucrose and dextrin irregularly.

For its cultivation, it is recommended the use of blood agar or 7 day chicken embryo, inoculated in allantoic cavity (dying at 24-48 hours). In the first case remain viable microorganisms refrigerated 2 weeks, and in the second six weeks.

Haemophillus paragallinarum is the pathogenic agent producer of poultry infectious coryza. This respiratory disease affects chickens (especially at the end of its growth), pheasants and guinea fowls. There are other bird species that are mainly asymptomatic carriers; although they can sometimes suffer any respiratory symptoms. It has high morbidity and low mortality. Its transmission is aerogenous and digestive, its period of incubation varies within 1-3 days, and young animals are more resistant than the old ones. Animals mainly present facial edema, serous abundant, sinusitis, conjunctivitis and nasal sinuses.

IV.- Haemolytic Poultry Choriza

Since October 1987, every autumn we have diagnosed a respiratory disease which mainly affects to chicken. This disease usually begins in early autumn in the North of the Iberian Peninsula and finishes in late autumn in the South of the Iberian Peninsula.

The effects of this disease are very similar to infectious Bronchitis’, with the difference of a screaming breathing, chicken presents white face (produced by a hemolytic anemia) and stops its growth.

Main injuries are in the right lung (mainly in the central area where presents bruises) and in the gallbladder which is enlarged due to the destruction of haemoglobin that leads to bile acids.

Referred birds of at least 50 farms after isolation and culture on blood agar, they achieved in all cases to isolate Haemophilus paragallinarum.

This disease is much more aggressive than the causing of poultry coryza (mentioned earlier) as it presents a mortality rate up to 30%-40%.

Starling (Sturnus vulgaris), which belongs to the family of Sturnidae, is a typical migratory bird of the Iberian Peninsula, whose migration coincides with the epidemiology of the disease.

In October they fly in large flocks, migrating to Southern Europe or Northern Africa, looking for warmer areas to spend winter.

They were captured (near farms with the described pathology) and were submitted to necropsy, where 50 specimens revealed same injuries than in chickens, but less aggressive. Cultures and isolations were done; resulting being fundamentally isolated Haemophillus paragallinarum.

They concluded that carriers (frequently asymptomatic) of the disease were starlings which year by year travel over our territories on their migratory way, being by aerogenous transmission the cause of its disease.

The administered treatment, after the completion of antibiograms, was antibiotic therapy with doxycycline. The administration of doxycycline at low doses during at least 7 days was the best result.

We recommend prophylactic vaccination of breeding birds. Please note that in epizootic zones we recommend the vaccination of broilers apart from the breeding birds.

V.- Conclusions

1.-Poultry pathology produced by hemolytic germs is increasing. This one has a seasonal periodicity related to migration of birds and evolutionary cycles of the rest of the vectors.

2.-It is very important that breeding hens are vaccinated against: hemolytic colibacillosis, poultry cholera, poultry coryza and hemolytic poultry coryza.

3.-We need to take preventive measures in order to control vectors.