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Megfigyelések csirkék adenovírus okozta zúzógyomorfekélyével kapcsolatban
Abstract
The authors studied two large-scale broiler chicken farms (A and B) where, contrary to the appropriate housing and feeding conditions, the feed consumption decreased, anorexia, retarded growth, anaemia and feather abnormality were experienced. On farm A, the rearing period extended by 4 days, the mortality rate increased by 4% and the mean slaughter weight decreased by 0.5 kg. On farm B, the rearing period did not, but the mortality rate increased by about 7%. The elevated mortality level appeared between 10-15 days and 10-21 days on farm A and B, respectively. Post mortem examination revealed that the lumen of the proventriculus, the gizzard and almost the whole length of the intestine was filled with brownish-red creamy content. In the gizzard, the overlaying keratinoid layer on mucosa was partly detached, brownish-red discoloured and bloody infiltrated. After removing the keratinoid layer, erosions of the mucosa were observed in a diameter of about 0.5-2.0 cm. Histopathological findings included the degeneration or desquamation of the keratinoid layer, necrotic mucosa, degeneration and disappearance of epithel cells, and oedematous lamina propria infiltrated by lymphocytes, macrophages and heterophils. In the affected epithel cells basophilic intranuclear inclusion bodies were observed. Cytopathogenic effect typical of adenoviruses was experienced on the inoculated tissue cultures. Presence of adenoviruses was confirmed by PCR in the supernatant of the passaged tissue culture and in the mucosa of the affected gizzards. The isolated adenoviruses proved to be FAdV-1 by phylogenetic analysis of the sequences of the PCR product. The judgement of the economic impact of the gizzard erosion is a complex problem. In order to get a correct diagnose, it is always necessary to consider all details, including the anamnesis of a flock, the results of clinical and post mortem examination, histopathology, virus isolation and identification.
... Tanimura et al. [1] reported adenoviral gizzard erosion for the first time from a natural outbreak in a flock of layer chickens. Subsequent reports generally originated from broiler flocks in Japan, but more recently also in Europe and Korea [2][3][4][5][6][7][8][9]. Experimental reproduction of adenoviral gizzard erosion by infection with FAdV-1 isolated from field outbreaks has been reported in specificpathogen-free (SPF) layers as well as in commercial broilers. ...
... Similar to this, decreased weight gain was described by Okuda et al. [11] in an experimental study of 1-week-old and 3-week-old commercial broilers. The generated data as well as information collected from field outbreaks [6,8,9] confirm that growth retardation in the course of FAdV-1 induced gizzard erosion may present a serious problem for the economic success of broiler production. Similar to the majority of other experimental studies set up to reproduce gizzard erosion, no other clinical signs were observed in the present investigation. ...
In the present study day-old specific-pathogen-free (SPF) and commercial broilers with maternally derived fowl adenovirus serotype 1 (FAdV-1) antibodies were orally infected with a European "pathogenic" FAdV-1, isolated from broilers showing signs of gizzard erosion. During the experiment, broilers were observed and weighed daily up to 17 days post infection (dpi). Clinically, both infected groups showed significant decrease of weight compared to respective negative control groups. Birds were examined by necropsy at 3, 7, 10, 14 and 17 dpi. Pathological changes in the gizzards were noticed in both experimentally infected groups from 7 dpi onwards. Macroscopically, erosion of the koilin layer and inflammation or ulceration of the gizzard mucosa were observed. Histologically, presence of FAdV-1 in intranuclear inclusion bodies of degenerated glandular epithelial cells was demonstrated by in-situ hybridization and inflammatory cell infiltration of the lamina propria, submucosa and muscle layer was detected. Tissue samples were investigated by a recently developed real-time PCR and the viral DNA load was calculated from gizzard, liver, spleen and cloacal swabs with the highest amounts of FAdV-1 DNA found in the gizzard. For the first time, successful reproduction of clinical signs in broilers as well as pathological lesions in the gizzard were achieved with a European FAdV-1 isolate displaying some genetic differences to so far reported virulent FAdV-1 from Japan. Furthermore, highest viral load in gizzards could be linked with macroscopical and histological lesions. Therefore, the conducted analyses provide important insights into the pathogenesis of adenoviral gizzard erosion.
The authors continuously monitor randomly-collected animal samples for the assessment of adenovirus diversity and to study viral evolution. In the present work, the results of molecular (PCR) screenings of dead or live specimens of different psittacine species are described. Based on the sequence of two fragments amplified from the viral DNA polymerase and the hexon gene, apparently identical siadenoviruses were detected in six dead birds of a domestic breeder, namely in the internal organs of 3 budgerigars (Melopsittacus undulatus), a cockatiel {Nymphicus hollandicus), an eastern rosella (Platycercus eximius) and a scarlet-chested parrot (Neophema splendida), as well as in the throat-swab of a live, red-crowned parakeet (Cyanoramphus novaezelandiae) that was confiscated at the state border and transferred to a zoo. Sequence analyses and phylogenetic calculations confirmed that the detected viruses are identical to psittacine adenovirus type 2 (PsAdV-2). PsAdV-2 was first detected in a plum-headed parakeet (Psittacula cyanocephala) and in an umbrella cockatoo {Cacatúa alba) in the United States. Thus, the present report is the first description of PsAdV-2 in Hungary and also in Europe. The host range of PsAdV-2 includes different bird species, a trait characteristic for avian siadenoviruses. Considering the results of the present survey, the number of parrot species that are potential hosts for PsAdV-2 increased to seven.
Molecular typing of 26 recent fowl adenovirus (FAdV) isolates obtained in Eastern Hungary between 2006 and 2011 was performed. The viruses were isolated on primary chicken embryo liver cell cultures from carcasses of chickens, sent for diagnostic investigation. The isolates were subjected to a PCR to amplify a fragment from the hexon gene. Sequence analysis of the amplicons revealed the presence of all the five FAdV species in the country, among them FAdV-B, which has been barely found in Hungary before. The three strains classified as FAdV-B might represent a novel type within this species, as their nucleotide sequence identity to strain 340 (type FAdV-5) is below the commonly accepted intratype limit. Most of the strains (63%) were classified into species FAdV-E (12 strains) and FAdV-D (7 strains) in the study. Four of the isolates proved to be the mixture of two adenovirus strains belonging to two different FAdV types, in three from these four cases, these two types even belonged to two different species. Analysing the pathological findings bolsters certain established connections between some FAdV types and disease conditions. Gizzard erosion was found in connection with FAdV-1 strains only, and inclusion body hepatitis with FAdV-D and -E strains.
Increased mortality connected with gizzard erosions has been observed in several flocks of White Leghorn chicks in Sweden. Bacterial infection of the gizzard wall was a common finding in chicks that had died from the disease. Infection with Clostridium perfringens is supposed to be the main cause of mortality, but the primary cause of the gizzard lesions has not been established. Resume L'augmentation de la mortalité en relation avec une érosion du gésier a été observée dans différents troupeaux de White Leghorn en Suède. Une infection bactérienne de la paroi du gésier a été communément trouvée chez les poulets mourants de cette maladie. L'infection par Clostridium perfringens est supposée être la principale cause de la mortalité mais l'étiologie primaire de ces lésions du gésier n'a pas été établie. Zusammenfassung Eine erhöhte Mortalität wurde im Zusammenhang mit Magenerosionen in mehreren Herden von Weißen Leghornhühnern in Schweden beobachtet. Bei den durch die Krankheit verendeten Tieren wurde in der Regel eine bakterielle Infektion der Magenwand festgestellt. Vermutlich ist die Infektion mit Clostridium perfringens die Hauptursache der Mortalität. Die primäre Ursache der Magenveränderungen wurde nicht geklärt. Resumen Se observó una mortalidad mayor en conección con erosions de molleja en varias parvadas en aves Leghorn blancas en Suecia. Fue un hallazgo común encontrar infección por bacterias en las paredes de la molleja en las aves que habían muerto por esta enfermedad. Se supone que la principal causa de la mortalidad se debe a una infección por Clostridium perfringens, pero la causa primaria de las lesiones en la molleja no ha sido establecida.
Six experiments have been completed on day-old male cross-bred chicks for periods of up to 2 and 4 weeks to learn more about the role of pyridoxine in the etiology of gizzard erosion. At the end of each experiment, chicks were sacrificed and their gizzards removed and scored for the severity and incidence of erosion. The results of these experiments confirm the previous finding that the severity and incidence of gizzard erosion is increased by B6 deficiency. They further show that taurocholic acid, at 1% of the diet, had a protective effect against this erosion. Feeding B6-adequate rations to chicks that previously had been fed a B6-deficient diet led to partial healing of gizzard erosions. Results also indicate that the feeding of purified diets to growing chickens produces a higher incidence of erosion than that of practical-type diets. Texture of the diet did nt influence the incidence of the erosion, because grinding a practical diet to the same fineness as a purified diet did not increase gizzard erosion. Pair-feeding experiments showed that gizzard erosion in partially starved chicks was not a specific result of anorexia but of deficiencies in certain nutrients, one of which is vitamin B6.
The results of a large scale trial confirmed preliminary findings that the feeding to chicks of a diet containing 4 mg/g of histamine can result in the production of localised lesions in the gizzard and depressed growth rate. This finding supports an earlier suggestion that when dietary fish meal is associated with gizzard erosion the condition is mediated, in part, by the histamine produced by certain types of bacterial spoilage of fish protein.
Cases of focal necrotic pancreatitis and gizzard erosion in chickens are reported. Intranuclear inclusion bodies were seen in necrotic pancreatic acinar cells and necrotic epithelial cells of the gizzard, and electron microscopy demonstrated virus particles in affected gizzard epithelium. Adenovirus antigens were detected immunohistochemically in these intranuclear inclusion bodies. These findings suggest that the necrotizing pancreatitis and gizzard erosion were associated with adenovirus infection.
Gizzard erosions and ulcers are associated with dietary deficiencies and toxins. A retrospective study of histopathology reports over an 8-year period (1985-92) found six cases of adenovirus inclusion body ventriculitis in broiler and leghorn chickens and captive bobwhite quail (Colinus virginianus) in south Georgia. The relationship between intralesional virus and the pathogenesis of ventricular lesions in chicks and quail in the present study is not known. /// Las erosiones de la molleja y las úlceras están asociadas con deficiencias dietéticas y toxinas. En un estudio retrospectivo de los reportes histopatológicos durante un período de ocho años (1985-92) se encontraron seis casos de ventriculitis con cuerpos de inclusión por adenovirus en pollos de engorde y gallinas leghorn, lo mismo que en codornices de Virginia (Colinus virginianus) localizadas en el sur de Georgia. En este estudio no se conoce la relación entre las lesiones virales y la patogenesis de las lesiones ventriculares en pollos y codornices.
Gizzard lesions were formed in specific-pathogen-free (SPF) white leghorn chickens inoculated with fowl adenovirus (FAV). The virus, serotype 1 FAV 99ZH strain (FAV-99ZH), was originally isolated from the gizzard mucosa of commercial broiler chickens exhibiting gizzard erosion with intranuclear inclusion bodies. Five-day-old and 53-day-old SPF white leghorn chickens were inoculated with FAV-99ZH by both oral and ocular routes and then examined at necropsy on days 3, 5, 7, 10, 14, and 21 postinoculation (PI). There were no clinical signs in any of the chickens after the inoculation. Focal gizzard lesions occurred macroscopically, however, in inoculated chickens at several experimental periods. FAV was recovered from tissue samples of the proventriculus, gizzard, pancreas, and rectum by day 10 or 7 PI but was not recovered from liver samples of any of the chickens. These results indicate that FAV isolated from gizzard erosion is able to reproduce gizzard lesions as necrosis and erosion in SPF white leghorn chickens and that it may have a greater degree of tissue tropism in gizzards and other digestive organs than in the liver.
The pathogenicity of a serotype 1 fowl adenovirus (FAV-99ZH), isolated from broiler chickens exhibiting gizzard erosion, was investigated in commercial broiler chickens. Five-, 3-, and 1-wk-old commercial broiler chickens were inoculated with FAV-99ZH by both oral and ocular routes. In the 5-wk-old chickens (trial 1), none of which had the maternal antibody to FAV-99ZH, severe gizzard erosions were observed on days 5, 7, and 10 postinoculation (PI). Among the 3-wk-old chickens (trial 2), which were separated into a control group and three treatment groups according to their maternal antibody titer levels, some chickens showed clinical signs such as depression and anorexia. Compared with the control group, all the treatment groups showed decreased weight gain. One treatment group, moreover, showed significantly decreased (P
Gizzard erosion in broiler chickens was investigated at 18 slaughterhouses in Japan. The condition was observed in 13 of them, and adenoviral gizzard erosion (AGE) was diagnosed histologically, immunohistochemically and virologically in the eroded gizzards from nine of these 13. The antigen-positive intranuclear inclusion body of group 1 fowl adenovirus was observed in the epithelial cells of the affected gizzards, and fowl adenoviruses were isolated from the lesions. In two of the slaughterhouses the total weights of the gizzards disposed of in three years were 3590 kg (0.40 per cent of the gizzards inspected) and 2880 kg (0.19 per cent). Sixteen of the 19 outbreaks of gizzard erosion on 15 farms that were confirmed in three of the slaughterhouses, including the previous two slaughterhouses, were diagnosed as AGE, and the condition was suspected in the other three outbreaks. Most of the adenoviruses isolated were identified as serotype-1 by PCR-restriction fragment length polymorphism. No apparent clinical signs were observed in any of the affected flocks.