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IBV genotype QX causes suficient disease in Europe for several commercial companies to have started developing live attenuated vaccines. Here, one of those vaccines (L1148) was fully consensus sequenced alongside its progenitor ield strain (1148-A) to determine vaccines markers, thereby enabling detection on farms. Twenty eight single nucleotide substitutions were associated with the 1148-A attenuation, of which any combination can identify vaccine L1148 in the ield. Sixteen substitutions resulted in amino acid coding changes of which half were in spike. One change in the 1b gene altered the normally highly conserved inal 5 nucleotides of the transcription regulatory sequence of the S gene, common to all IBV QX genes. No mutations can currently be associated with the attenuation process. Field vaccination strategies would greatly beneit by such comparative sequence data being mandatorily submitted to regulators prior to vaccine release following a successful registration process

Since 1996 a new Infectious Bronchitis virus (IBV) genotype, referred to as Q1, circulated in China and was reported for the Þ rst time in Italy in 2011, associated with an increase of mortality, kidney lesions and proventriculitis. During a 2013 Northern Italian outbreak of respiratory disease in a chicken ß ock, an IBV strain was detected by RT-PCR and characterized as Q1-like. The virus was isolated and named CoV/ Ck/Italy/I2022/13. All coding regions of the isolate were sequenced and compared with 130 complete genome sequences of IBV and TCoV, downloaded from ViPR, and showed most identity with a Chinese strain CK/CH/LDL/97I (p-distance=0.044). To identify potential recombination events a complete genome SimPlot analysis was carried out which revealed the presence of possible multiple recombination events, but the minor parent strains remained unknown. A phylogenetic analysis of the complete S1 gene was performed using all complete S1 sequences available on ViPR and showed that the isolate clustered with an Q1-like strain isolated in Italy in 2011 (p-distance=0.004) and a group of Chinese Q1-like strains isolated from the mid 90’s (p-distance=0.001 with GenBank Accession Number CK 577410). It could be hypothesized that the isolate descended from the Italian 2011 Q1-like strain or was the result of a separate introduction from China, through commercial trade or migratory birds; but the data did not distinguish between these possibilities

A total of 170 birds of prey admitted to two Wildlife Rescue and Rehabilitation Centers of Italy were examined. Birds were subdivided in diurnal (n=15) and nocturnal (n=7) species, sampled by cloacal swabs and examined for Campylobacter spp. by cultural and molecular methods. Campylobacter spp. was isolated in 43 out of the 170 (25.3%) birds of prey examined. Among these, 43/43 (100%) were identiied as C. jejuni and 10/43 (23.3%) were identiied as C. coli recovered from mixed infections. Diurnal birds of prey showed a signicantly higher prevalence value (P = 0.0006) for Campylobacter spp. than nocturnal birds of prey.

Forty common swifts (Apus apus), synanthropic birds living in an urban environment closely with humans and other animals, were hospitalized in the public veterinary hospital of the Regional Reference Center of Urban Veterinary Hygiene located in Naples, Campania Region, Italy. Each bird was sampled for bacteriological analyses. Out of 40 common swifts examined, eight were found positive for Salmonella enterica serovar Infantis although no sign of salmonellosis (e.g. diarrhoea) was shown. Our results suggest this avian species as a novel potential reservoir for one of most important Salmonella serovars.

Avian metapneumovirus (AMPV) causes an upper respiratory tract infection in turkeys leading to turkey rhinotracheitis. In other avian species, including chickens, it is also involved in the etiology of multifactorial diseases such as swollen head syndrome. Sensitivity of wild birds to AMPV and their role in maintaining and spreading the virus to poultry is still a matter of debate. Recently the sensitivity of pigeons to AMPV of subtype A or B has been claimed, based on very limited PCR detections from wild or experimentally infected birds. In order to have conclusive evidence regarding the sensitivity of pigeons to AMPV of subtype B and its role in spreading the virus to turkeys, two experimental trials were planned in secure isolation conditions. In trial 1 two isolators were modified to host turkeys and pigeons in the same environment, separated only by a net. Drinkers were shared between groups. Pigeons were infected with AMPV and housed in one isolator with naïve turkeys. Similarly turkeys were infected and housed with naïve pigeons. Additional turkeys and pigeons were kept in different isolators as uninfected controls. Post-infection clinical signs, virus shedding and immune response were assessed for three weeks. In trial 2, commercial two-weeks old turkeys were divided in two groups and housed in two different isolators. Birds in isolator A were challenged as previously described. Four days post-infection, 7 weeks old naïve pigeons were introduced in the isolator A and kept with the infected turkeys for 24 hours, then removed, sprayed with 0,5 % of Wirkon S® solution. After 10 minutes, pigeons were rinsed with water, dried, and introduced in the isolator B, where 10 naïve turkeys were housed. Clinical sign were monitored for 10 days. Pigeons were found refractory to AMPV experimental infection and neither able to spread the virus to naïve turkeys. Our paper shows that pigeons are highly unlikely to play any relevant role in the environmental spread of subtype B AMPV. Pigeons are not biological vector or reservoir species for AMPV subtype B.

An outbreak of Avian metapneumovirus (AMPV) infection in Guinea fowl is reported in Northern Italy. A subtype B AMPV strain, named aMPV/B/IT/GuineaFowl/1818/12, was isolated and sequenced in F and G genes. Philogenetic analysis showed that the isolate clustered together with other AMPVs of subtype B isolated in Italy from 2001. The factors involved in determining the outbreak are discussed.

The study investigates the ability of subtype A Avian metapneumovirus (AMPV) to accept foreign genes and be used as a vector for delivery of Infectious bronchitis virus (IBV) QX genes to chickens. Initially the GFP gene was added to AMPV at all gene junctions in conjunction with the development of cassetted full length DNA AMPV copies. After 3 recombinant viruses had been recovered by reverse genetics, GFP positions supporting gene expression while maintaining virus viability in vitro, were determined. Subsequently, either S1 or nucleocapsid (N) genes of IBV were positioned between AMPV M and F genes, while later a recombinant was prepared by inserting S1 and N at AMPV MF and GL junctions respectively. Immunofluorescent antibody staining showed that all recombinants expressed the inserted IBV genes in vitro and furthermore, all recombinant viruses were found to be highly stable during serial passage. Eyedrop inoculation of chickens with some AMPV-IBV recombinants at one-day-old induced protection against virulent IBV QX challenge 3 weeks later, as assessed by greater motility of tracheal cilia from chickens receiving the recombinants. Nonetheless evidence of AMPV/IBV seroconversion, or major recombinant tracheal replication, were largely absent.

Direct diagnosis of avian Metapneumovirus (AMPV) infections rely on molecular techniques more than on virus isolation due to the fastidious nature of the virus. Six real-time reverse transcription PCR (qRT-PCR) protocols for the detection and differentiation of AMPV subtype A and B were developed in N (two tests), F, SH (two tests) and G genes. In five assays SYBR Green I was used as detection system, and in one, molecular beacon probes. Specificity was evaluated using various AMPV strains and other avian respiratory viruses such as Newcastle disease virus, Infectious laryngotracheitis virus and Infectious bronchitis viruses. All tests were able to detect AMPVs and failed to detect non-AMPV viruses, and five out of six of them were also able to discriminate between AMPV A and B subtypes. Sensitivity was determined using serial dilutions of RNA extracted from AMPV of both subtypes. The best results in terms of specificity and sensitivity were given by the qRT-PCR protocol developed using a set of primers designed in the SH gene.

Scopo del lavoro è stato quello di valutare il grado di inquinamento batterico di uova di pollo nelle diverse fasi dell’incubazione, dall’arrivo alla schiusa, in un incubatoio industriale. Sono state campionate 20 partite. Per ogni partita sono state prelevate 20 uova all’arrivo, tenendole distinte per fornitore (provenienza Francia, Italia, Portogallo) e 40 alla schiusa: 20 non schiuse, con guscio integro, ed altre 20 non schiuse ma con guscio parzialmente beccato. L’esame batteriologico per la ricerca in particolare di Pseudomonas aeruginosa, Escherichia coli e Salmonella spp. È stato eseguito da gusci e tuorli mentre solo dalle uova in arrivo e da quelle in schiusa non beccate è stata determinata la carica batterica totale del guscio. E. coli è stato il batterio maggiormente isolato. Esso era presente in percentuale crescente nelle uova in arrivo, in quelle in schiusa (non beccate e beccate). Altri batteri appartenenti alle Enterobacteriaceae sono stati isolati in percentuale inferiore rispetto a E. coli e quasi sempre associati ad esso. In particolare sono stati isolati: Salmonella livingstone, Citrobacter spp. (C. koseri, C. amalonaticus), Enterobacter agglomerans, Proteus mirabilis, Serratia liquefaciens e Providencia alcalifaciens. Pseudomonas aeruginosa era presente nelle uova in arrivo ed in quelle beccate, ma in percentuale inferiore rispetto a E. coli. Salmonella livingstone è stata isolata solo in due pool di sacchi vitellini, da uova beccate. Altri batteri isolati sono stati Sphingomonas paucimobilis dal guscio di uova in arrivo ed Acinetobacter spp. nel sacco vitellino.

Per la Malattia di Newcastle (ND) e la Rinotracheite del tacchino (TRT), vaccini vivi attenuati vengono comunemente somministrati nei primi giorni di vita ad almeno una settimana di distanza l’uno dall’altro per il timore che si verifichino interferenze tra virus vaccinali. La possibilità di associare in incubatoio tali interventi avrebbe numerosi vantaggi sia di ordine pratico, che economico e sanitario. In quest’ottica diventa fondamentale assicurarsi che non ci siano interferenze negative tali da compromettere l'efficacia delle vaccinazioni o addirittura causare effetti patologici indesiderati. L’obiettivo del presente lavoro è stato valutare, in condizioni sperimentali, l'interferenza fra due diversi ceppi vaccinali di NDV e uno di Metapneumovirus aviare (AMPV), agente della TRT, somministrati nel tacchino in associazione ad un giorno di vita, secondo un possibile schema vaccinale praticabile in incubatoio. La prova è stata eseguita in condizioni di isolamento biologico in isolatori per pollame. Ottanta tacchinotti commerciali sono stati suddivisi in gruppi e vaccinati al primo giorno di vita per AMPV col ceppo VCO3, e per NDV con i ceppi B1 o VG/GA, somministrati singolarmente o in associazione (VCO3 + B1 o VCO3+VG/GA). Nei 30 giorni successivi, ad intervalli stabiliti, è stata valutata l’eliminazione respiratoria dei virus vaccinali mediante real time RT-PCR, e la risposta anticorpale umorale per NDV ed AMPV, mediante inibizione dell’emoagglutinazione ed ELISA, rispettivamente. Infine, parte dei soggetti vaccinati per AMPV, singolarmente o in associazione, sono stati infettati sperimentalmente con AMPV allo scopo di valutare la protezione immunitaria mediante misurazione della sintomatologia clinica. I risultati ottenuti permettono di concludere che la somministrazione al tacchino di un giorno di vita di vaccino vivo attenuato AMPV ceppo VC03, in associazione con i vaccini vivi NDV sia ceppo B1 sia ceppo VG/GA, conferisce protezione al challenge con AMPV sovrapponibile a quella evocata dal vaccino somministrato singolarmente, e non determina interferenze negative sulla replicazione dei virus vaccinali a livello respiratorio e sulla risposta immunitaria umorale. Resta da verificare se la protezione nei riguardi di NDV a seguito di vaccinazione combinata sia sovrapponibile a quella ottenibile con la vaccinazione singola.