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This work was undertaken to assess the long-term impacts of a ruminal transponder, used for electronic identification, on ruminal motility and on health and performance of cattle, as well as to study the electromagnetic effects on ruminal bacteria in vitro. A passive transponder (51.4 g, 67 x 17 mm) was delivered into the forestomachs of 8 calves, 32 bulls, 10 heifers, and 40 dairy cows. Final readability was 87.5% in calves, 96.9% in bulls, 90% in heifers, and 100% in cows at 481, 360, 650, and 601 d, respectively, after transponder administration. The transponder did not affect production or reproduction of cows over a 2-yr period, or performance of bulls, or mortality compared with control animals. Chewing movements per bolus were lower (P < 0.01) in treated animals than in controls (49.6 vs. 52.2, 51.2 vs. 63.6, and 57.0 vs. 59.7 for bulls, heifers, and cows, respectively). Regurgitation frequency (number of boluses/10 min) tended to be greater in treated cattle: 12.4 vs. 11.3 (P = 0.07), 11.3 vs. 10.6, and 11.3 vs. 10.7 (P = 0.08) for bulls, heifers, and cows, respectively. Rumination patterns of calves fitted with transponders within the first weeks of life were similar to controls. During the experiment, 43 treated animals (8 calves, 29 bulls, and 6 cows) were slaughtered. Thirty transponders were localized in the reticulum (3 calves, 24 bulls, and 3 cows), 11 in the rumen (4 calves, 4 bulls, and 3 cows), and 2 were not recovered (1 calf and 1 bull). Within the calves, 57% of the boluses were found in the rumen. In 8 reticula (2 calves and 6 bulls) and 1 rumen (1 cow), an impression left by physical contact of the transponder was observed, although histological examination did not reveal specific lesions in the mucosa of the dystrophic areas. In strained, whole ruminal contents incubated in vitro, pH values were lower after 24 and 48 h (P < 0.001) of continuous exposure to an electromagnetic field induced by the transponder-reading system. After 48 h of incubation, total bacterial numbers and NH 3 -N concentration were greater (P < 0.001) in exposed flasks than in controls. These data indicate that the transponder may alter, via mechanical action, the reticuloruminal mucosa and rumination patterns. Furthermore, the transponder may increase, via its electromagnetic action, the growth rate and metabolic activity of ruminal bacteria.

Adrenocortical and thyroidal hormones are physiological indicators of various forms of stress in the fowl. In order to establish possible variations in corticosterone levels, blood samples were collected from ISA Brown hens reared in three different housing systems (cage, floor and organic way). Results showed that corticosterone concentrations were highest in caged hens, intermediate in organic reared hens and lowest in floor reared hens. It could be assumed that in the last one system birds have an adequate space in controlled environment that permits them to satisfy, though partially, their behavioural needs without the presence of different chronic stress factors acting in the other systems.

Summary An outbreak is reported of inclusion body hepatitis in psittacines from a private aviary, in which several birds aged between 35 and 75 days had died without showing any clinical signs. Histological examination of the livers revealed severe hepatic damage with presence of large basophilic intranuclear inclusion bodies. Avian adenoviruses were isolated from the affected livers. Characterization of the isolates by means of restriction endonuclease analysis showed that they were similar to reference strain SR49 (serotype 3) which is associated with inclusion body hepatitis in chickens. This finding was confirmed by the virus neutralization test.

Twenty-seven cases of nephroblastoma were observed in 54 culled light meat broilers during a 1-year period. The tumours were generally unilateral and varied in size. Metastases were not observed. Histopathological studies showed epithelial and mesenchymal structures at different stages of development. Ultramicroscopy and immunohistochemistry findings revealed viral particles in intercellular spaces and in the lumen of the tubules not morphologically unlike avian leukosis/sarcoma viruses.

This paper describes an outbreak of disease caused by Hafnia alvei in pullets. Cloudy swelling and the fatty degeneration of liver associated with splenic lymphocytic depletion were the most preminent lesions. The organism was identified by biochemical tests and by a Hafnia-specific bacteriophage test. Laying hens and pullets were infected experimentally with the organism by the oral and intraperitoneal route, and the clinical and pathological effects were similar to those observed in naturally infected subjects. The use of more sensitive diagnostic tests is suggested to avoid the possibility of a misdiagnosis due to similarities between this organism and Salmonella species. Resume Infection a Hafnia alvei chez des poulettes en Italie Cet article decrit un cas de maladie causee par Hafnia alvei chez des poulettes. Les lesions les plus preeminentes ont ete une degenerescence graisseuse du foie qui avait une apparence gonflee et marbree, et une depletion lymphocytaire au niveau de la rate. Le germe a ete id...

During a survey effected in a meat pigeon slaughterhouse of central Italy, atrophy of primary lymphoid organs (bursa of Fabricius and thymus) and hypoplasia of bone marrow were observed. Histologic, ultrastructural, and hematologic examinations were performed on a total of 80 randomly selected 30-day-old meat pigeons. By histologic studies, lymphocytic depletion and necrosis with cyst formations in the bursa of Fabricius were detected in all subjects that showed thymus and bursa atrophy at necropsy. Basophilic intranuclear inclusions were also observed in bursal cells. After ultrastructural studies, these inclusions were proved to be viral particles resembling circoviruslike particles in morphology and size. Severe lymphocytic depletion of the bursa was plausibly associated with the presence of the viral particles.

The aim of this study was to evaluate the possible differences in the intestinal microflora composition among the different rearing systems (conventional vs organic) and the Salmonella diffusion using bacteriological techniques. The results showed that the differences between the two groups at the same age, expressed by the bacterial count, are not conclusive in showing an influence of the rearing systems. Salmonella Hadar was isolated once in caeca of conventional and once in caeca of organic ones. Though the results are preliminary and referred to a well defined geographic area in Central Italy, Salmonella detection does not seem to be common in conventional and organic chicken farms.

Il capitolo tratta la tecnica necroscopica da utilizzare nell'esame cadaverico delle specie aviarie. La metodica viene descritta con precisione in tutti i suoi dettagli e corredata da foto esemplificative inserite nel capitolo. Nella descrizione non mancano richiami alla anatomia normale o patologica degli organi ed apparati esaminati, nè alle particolarità di specie.

Il capitolo tratta delle malattie causate nei volatili dai virus appartenenti alla famiglia Paramyxoviridae. In particolare vongono approfondite la Malattie di Newcastle (da Paramyxovirus 1), le infezioni dal altri Paramyxovirus, la Rinotracheite del Tacchino e la Sindrome della Testa gonfia (causate entrambi da Metapneumovirus aviare). Per ogni malattie viene trattata l'eziologia, gli aspetti clinici ed anatomopatologici nonchè le metodiche diagnostiche e la profilassi.