Outbreaks of inclusion body hepatitis (IBH) and adenoviral gizzard erosion have been anecdotally reported in Greece since approximately 2011. However, a relevant increase in clinical outbreaks compatible with IBH has been described since 2014. Unfortunately, with limited exceptions, only serological assays were performed, and involved strains were not properly characterized. In the present study, 35 outbreaks were investigated in the period between July 2017 and February 2018 in Greece. In addition to clinical and histopathological diagnosis, fowl adenovirus (FAdV) presence was investigated by PCR and sequencing. Thirty-four out of 35 samples tested FAdV positive. Twenty-nine (85.29%) and 5 (14.71%) strains were classified as FAdV-E and FAdV-D, respectively. Fowl adenovirus-E strains were genetically homogeneous and formed an independent cluster of Greek-only sequences, including the sole previously available sequence, suggesting the prolonged circulation of this species in Greece. On the contrary, FAdV-D strains were more heterogeneous and closely related to strains sampled in other European countries, testifying the occurrence of multiple introduction events. The evaluation of phylogenetic relationships, geographic clustering, age of infection, and origin of the broiler breeder flocks suggests that both vertical and horizontal transmission are important in FAdV epidemiology in Greece and highlights the limited efficacy of currently implemented control measures. Of note, a significantly higher mortality was observed in precociously infected flocks, likely because of the higher susceptibility of younger animals. This evidence stresses the need of preventing vertical and/or early infection to limit the economic impact of adenovirus-induced diseases.

In recent years, the applicability of prebiotics, probiotics and their mixtures, defined as synbiotics, in poultry production has received considerable attention. Following the increasing regulation of antibiotic use, these nutraceuticals are seen as an alternative way to sustain production efficiency and resistance to pathogens and stressors by modulating birds’ gut health. The aim of this study was to evaluate the benefits provided under field conditions by administering the multi-species synbiotic PoultryStar^® sol to broilers in drinking water. To this purpose, three Ross 308 broiler flocks, representing separate progenies of a breeder flock which was treated with the same synbiotic, were housed in separate farms, divided into treatment and control groups, and followed throughout the productive cycle. Synbiotic administration was shown to improve gut health even in absence of a challenge, with limited changes in terms of macroscopic intestinal lesions and more overt differences related to histopathological scores and villi length. Synbiotic-fed chickens performed consistently better in terms of body weight gain, feed conversion ratio and survivability. Lastly, the evaluation of the caecal microbiome through next-generation sequencing highlighted the effects of synbiotic supplementation on the composition of the bacterial population, the implications of which will, however, require further studies to be better comprehended.

In recent years, a rising interest has been directed towards the use of nutraceuticals in the zootechnical sector, including probiotics, prebiotics, and synbiotics, as a way to support production efficiency and cope with the increasing limitations to the use of antibiotics. In poultry, however, most studies on these products have been conducted on broilers, while less information is available on their benefits to other productive categories. The present field study aimed to assess the effects of a multi-species synbiotic product (PoultryStar® sol) on the gut health and productive performance of broiler breeders. A total of 24761 day-old Ross 308 parent stock chicks were acquired from a single hatchery and placed on the same farm. Female chicks were divided into three groups and raised in different houses (A, B, and C), in which males were introduced at the age of mating and followed until 40 weeks of age. The synbiotic was provided by drinking water to the flocks in houses A and B, while house C was kept as control. Following the manufacturer’s guidelines, the product was administered intermittently once every two weeks, except in the first and the twenty-first week when it was supplied for three consecutive days. Data on performance parameters, egg quality traits, bacterial enteritis scoring, intestinal morphometry, and histopathology were recorded, and the caecal content was collected at 15, 25, and 40 weeks of age to investigate the intestinal microbiota using high-throughput next-generation sequencing. Synbiotic-treated hens showed significantly higher survivability during production compared to the control group. No clear differences were observed between treated and control chickens in terms of egg production and quality, and the effect of the synbiotic on weight gain also appeared limited. From 25 weeks onwards, synbiotic-treated chickens scored better in terms of macroscopical lesions and had longer intestinal villi. Significant differences in crypt length and histopathological lesions were also found at multiple sampling points. A treatment effect on caecal bacterial composition was detected with a differential abundance of Gastranaerophilales, Lachnospiraceae, Helicobacter, Ruminococcaceae, and Clostridia, among others. Taken together, obtained results support the beneficial effects of the intermittent administration of the synbiotic product PoultryStar® sol on the gut health of broiler breeders. Keywords: Broiler breeder, Gastrointestinal health, Histopathology, Microbiota, Synbiotic

Pigeon breeders in Central and Northern Greece often report pox-like skin lesions in their flocks. However, these reports have not been scientifically validated, and no investigation has determined the presence or prevalence of pigeon pox virus in Greek avian populations. The present study aimed to report the detection of pigeon pox in a flock of pigeons in Karditsa, Greece, confirmed by polymerase chain reaction (PCR) analysis. Following a comprehensive review of the existing scientific literature, the present study provided the first documented confirmation of pigeon pox virus in Greece. In September 2025, a breeder from Karditsa, Greece, reported cutaneous and respiratory signs in 40 of 250 juvenile pigeons in a loft of 450 pigeons. The flock was vaccinated only against paramyxovirus, not against pigeon pox. Lesions on the skin, beak, and eggs persisted for 4-8 weeks, with no mortality. The breeder administered doxycycline, enrofloxacin, and local ganciclovir for trichomoniasis; however, the treatment was unsuccessful. Wart-like lesions from the beak, skin, legs, and eyelids were collected for molecular analysis by PCR targeting Avipoxvirus-specific genomic regions, confirming the diagnosis of pigeon pox virus infection. The clinical history, physical examination, and necropsy findings, along with the PCR results, confirmed the poxvirus infection. The present study confirmed the presence of pigeon pox virus in Greece and emphasized the importance of raising awareness and conducting additional epidemiological surveillance of Avipoxvirus infections in domestic pigeons.

Swine influenza A virus (swIAV) is an endemic respiratory pathogen of pigs with zoonotic relevance. We analysed retrospective serological data from routine diagnostic submissions (January 2023–May 2026) to a single laboratory, comprising 2003 sera from 66 reports on 44 commercial farrow-to-finish farms in seven regions of mainland Greece, tested with a nucleoprotein ELISA that cannot distinguish vaccine-, maternally, or infection-derived antibodies. Overall seroprevalence was 46.4% (929/2003; farm-clustered 95% CI 39.1–53.8%); at least one seropositive animal was found in 51 of 61 farm-years and in 36 of 44 farms. Seroprevalence differed by production stage (p < 0.001): it was highest in multiparous sows (75.9%) and suckling piglets (70.7%), both likely influenced by sow vaccination and maternally derived antibodies, intermediate in gilts (46.0%) and nursery pigs (38.6%), and lowest in growers (24.8%) and finishers (24.0%), in which antibodies indicate prior exposure rather than current circulation. No consistent temporal trend was detected, although some adjusted models suggested higher seroprevalence in 2025–2026. Regional seroprevalence ranged from 10.1% (Thessaly) to 61.0% (West Greece); the association was significant with the standard but not the bias-reduced cluster-robust estimator (p = 0.014 and p = 0.39) and persisted after adjustment for year and stage, but it rests on few farms per region and is considered exploratory. As a convenience sample of diagnostic submissions, these data provide descriptive rather than nationally representative estimates and support the addition of molecular, subtype-level surveillance.