Background and Aim: The importance of monitoring antimicrobial residues in food is underlined by increasing worries about food safety and public health. The potential toxicity of azithromycin (Az) on broilers and its impact on chicken meat residues require further investigation. This study assesses Az’s toxicity effects and associated risks in broiler chickens through evaluation. Materials and Methods: One hundred and twenty chicks were distributed into four equal groups randomly. Each group received different daily oral doses of Az: 200 mg/kg for Az1, 100 mg/kg for Az2, and 50 mg/kg for Az3. The FAz group was given plain water. High-performance liquid chromatography was used to measure Az residue levels in muscle and liver. Oxidative markers (malondialdehyde [MDA], superoxide dismutase [SOD], catalase [CAT]), liver and kidney function tests, and histopathological examination were conducted. Results: The levels of alanine aminotransferase and aspartate aminotransferase increased in Az1 and Az2 groups from 8 h to 3 days and decreased slightly in Az2 by 7 days, while they remained normal in Az3. The levels of uric acid and creatine in the Az1 and Az2 groups increased from 8 h to 3 days and subsequently decreased in Az2 by the 7th day. Az1 group showed the highest increase in MDA levels within 7 days. With higher Az doses, SOD and CAT levels showed a more significant decrease post-treatment. 9.1 μg/kg Az1 liver had the highest residues, whereas none were detected in muscle. Conclusion: At higher doses, Az caused significant liver and kidney damage, whereas lower doses had negligible effects. Muscle tissue contains fewer Az residues than liver. Assessing risks and ensuring compliance with regulations necessitate constant surveillance of Az residues in food. The health implications and risk management insights necessitate further investigation into the long-term effects of Az residues. Keywords: antibiotic residues, azithromycin, broiler chicken, liver functions, oxidative stress.

Background and Aim: Bone marrow-derived mesenchymal stem cells (BM-MSCs) transplantation and their hepatogenic differentiated cells (HDCs) can be applied for liver injury repair by tissue grafting. Regenerative potentiality in liver cirrhosis models was widely investigated; however, immunomodulation and anti-inflammation in acute hepatitis remain unexplored. This study aimed to explore the immunomodulatory and evaluate twice intravenous (IV) or intrahepatic (IH) administration of either BM-MSCs or middle-stage HDCs on aflatoxin (AF) acute hepatitis rat model. Materials and Methods: BM-MSCs viability, phenotypes, and proliferation were evaluated. Hepatogenic differentiation, albumin, and a-fetoprotein gene expression were assessed. AF acute hepatitis was induced in rats using AFB1 supplementation. The transplantation of BM-MSCs or their HDCs was done either by IV or IH route. Hepatic ultrasound was performed after 3-weeks of therapy. Cytokines profile (tumor necrosis factor-α [TNF-α], interleukin [IL]-4, and IL-10) was assessed. Hepatic bio-indices, serum, and hepatic antioxidant activity were evaluated, besides examining liver histological sections. Results: Acute AFB1 showed a significant increase in TNF-α (p<0.01), liver enzyme activities (p<0.05), as well as decrease in IL-4, IL-10, and antioxidant enzyme activities (p<0.05). Cytokines profile was ameliorated in groups treated with IV and IH BM-MCs, showed a negative correlation between IL-4 and TNF-α (p<0.05), and a positive correlation between IL-10 upregulation and TNF-α (p<0.01). In IV HDCs treated group, positive correlations between IL-4 and IL-10 downregulation and TNF-α were observed. However, in IH HDCs group, a significant positive correlation between IL-4 and IL-10 upregulation and TNF-α, were recorded (p<0.05). In addition, IV BM-MSCs and IH HDCs treatments significantly increased antioxidant enzymes activity (p<0.05). IV and IH BM-MSCs significantly ameliorated liver transaminase levels, whereas IH HDCs significantly ameliorated alanine aminotransferase activity and nitric oxide concentration (p<0.05). Conclusion: The administration routes of BM-MSCs did not demonstrate any significant difference; however, the IH route of HDCs showed significant amelioration from the IV route. On the other hand, it showed noticeable anti-inflammatory and immunomodulatory improvements in aflatoxicosis rats. Therefore, it can be concluded that acute hepatitis can be treated by a noninvasive IV route without the expense of hepatogenic differentiation. Further research using clinical trials that address several problems regarding engraftment and potentiation are needed to determine the optimal manipulation strategy as well as to achieve better long-term effects.

Background: Pigeon leukosis is primarily caused by avian leukosis virus subgroup A (ALV-A). It infects and transforms lymphoid cells, leading to the development of tumors in various lymphoid tissues and other organs especially the liver. Aim: This study was conducted to diagnose lymphoid leukosis in a naturally infected pigeon flock in Egypt. Methods: Tissue specimens from the liver, spleen, thymus, kidney, lung, proventriculus, gizzard, intestine, pancreas, heart, pectoral muscle, ovary, and testes were collected from infected birds for pathological and immunohistochemical examinations. Results: Clinical signs were generally non-specific and comprised weakness, dehydration, and emaciation. Gross lesions were mostly in the liver and spleen, in the form of minute white nodules scattered on the liver surface. Microscopic examination of the liver, spleen, and kidneys showed masses of uniform sizes and the presence of differentiated lymphoid cells. These cells appeared as large mononuclear cells with poorly defined cell membranes. Immunohistochemical investigation exhibited that the ALV-A positive indicators were chiefly accessible in the liver, ovary, spleen, and kidney. Conclusion: Lymphoid leukosis in pigeons could be provisionally diagnosed by a pathological picture of characteristic tumors and confirmed by immunoreactivity of viral antigens in different tissues.

Fowl adenoviruses are opportunistic emerging viruses that spread widely in fowls, infecting birds of all ages, including young broiler chicks. This study aims to genotype the current adenovirus strains associated with inclusion body hepatitis hydropericardium syndrome (IBH-HPS) among infected broilers in Upper Egypt and to evaluate their pathogenic features. In 2024, 100 tissue samples were collected across Assiut and Sohag governorates in Upper Egypt for genetic characterization and pathogenicity evaluation. FAdVs were detected in 22% (11/50) of flocks. Typical FAdV lesions of dead embryos were observed after seven days post egg inoculation. Regarding the PCR assay of the hexon gene, only 8 of 30 samples were confirmed positive at 897 bp, yielding a 26.6% positivity rate. The remaining samples were considered negative using established RT-qPCR protocols for other viral pathogens. Partial sequencing of the hexon gene revealed that FAdV isolates (n = 4) clustered within FAdV species-D serotype 2/11, as determined by phylogenetic analysis. The four isolates shared (98–99%) and (94–100%) nucleotide and amino-acid similarities to FAdV-D of Israeli strains (2019–2020) and contemporary Egyptian isolates (2022), respectively, and low genetic divergence (54–81%) in comparison with other documented species. The amino acid sequence alignment and 3D structure indicate that the four immunogenic HVRs are located in the L1 region of the hexon protein, and that the highly conserved ⁹¹GQMTT⁹⁵, a specific region for FAdV-D serotype 2/11, is present. Regarding pathogenicity, the gross and histopathological findings observed clearly demonstrate the systemic pathogenicity of FAdV-2/11 in the infected group, with a final mortality rate of 30% at seven days post-infection (dpi). The FAdV DNA in hepatic tissues and cloacal swabs was confirmed by the PCR method at 3 dpi and 5 dpi. These results emphasize the circulating of FAdV-2/11 species D in Upper Egypt and highlight the significant need for a single inactivated vaccine that effectively targets the relevant FAdV serotypes to achieve broader and more efficient protection.

This work was carried out to evaluate the efficacy of oregano powder 10% used as a prophylactic treatment in broiler chickens experimentally infected with avian pathogenic E. coli O27 (APEC O27) strain -local isolate-. Hematological and serum biochemical parameters, as well as histopathology of the vital organs, were investigated. A total of 200 chickens -aged 19 days old- were randomly allocated into 4 equal groups; Normal control (G1), Infected (G2), Oregano control (G3), and Oregano-Infected (G4). Chickens of (G3) and (G4) were supplemented with oregano powder that contains 10% oregano essential oil in the diet (250 g /ton diet) from the 1st day old till the end of the experiment. At the age of the 19th, 20th, and 21st day, chickens of (G2), and (G4) were infected with 0.2 ml of APEC O27 (1×107 CFU/chick) via the intratracheal route. On the 3rd, 6th, 10th, and 21st day post-infection, blood and tissue samples from all groups were collected for laboratory examinations of the hemogram, serum biochemistry, and histopathology of the vital organs. Chickens of (G2) showed gasping, dullness, loss of appetite, and ruffled feathers. Birds of (G3) showed no symptoms, while those of G4 showed mild symptoms. The mortality rates in chickens of (G2), (G3), and (G4) were recorded 30%, 0%, and 4%, respectively. Birds of (G2) revealed macrocytic hypochromic anemia, leukocytosis accompanied by heterophilia, and lymphopenia. The activities of AST and ALT enzymes and the values of uric acid and creatinine were increased while those of protein profile were decreased. In oregano supplemented groups, no significant alterations were detected. Birds of (G2) and (G4) revealed histopathological alterations in the lungs, trachea, liver, spleen, and kidneys. Finally, APEC O27 caused changes in blood picture, liver and kidney functions as well as histopathology of the internal organs. Oregano powder (at a dose of 10% in diet) could be used as prophylactic treatment for APEC O27 in chickens from the 1st day of age.

Avian leukosis virus Subgroup-J (ALV-J) is an avian retrovirus affecting a wide range of avian species, and has posed a great threat to the local poultry with significant losses. In Egypt, ALV-J has been actively monitored in various breeder flocks. This study investigated 200 eggs from ALV-J positive breeders, confirmed positive-polymerase chain reaction (PCR)-ALV-J, collected from a hatchery between January 2022 and December 2023. 200 tissue specimens (liver, heart, spleen, kidney, and lung) were collected from suspected embryos for PCR test, immunopathological identification, and sequencing analysis. To the best of our understanding, this is the first study specifically detecting ALV-J infection in chicken embryos in Egypt. The current study focuses on the genetic evolution and sequencing analysis of ALV-J isolates from chicken embryos across three Egyptian governorates: El-Sharkia, Al-Qalyubiya, and New Valley. Postmortem findings of the infected embryos showed stunting, curling, dwarfing, hemorrhagic body surface, enlarged liver, and congestion of chorio-allantoic membranes (CAM). Histopathological observation demonstrated no lymphoid or myeloid cell infiltrations, only degenerative changes and congestion of the examined organs existed. The immunohistochemical staining confirmed that the viral-positive signals were visceral tissues as the spleen, liver, and kidney. Only 30 samples were PCR-positive for ALV-J gp85 gene at size of 545 base pairs with a prevalence rate of 15%. Two ALV-J positive samples were sequenced and deposited in the Genbank under accession numbers (PQ119499 - PQ119500, ALV-J-II). ALV-J- gp85 gene phylogeny showed that the AlQalyubiya-1-EGYALVJ-env isolate is highly genetically correlated to Chinese strains (KJ179914-ALV-J-GD27, KJ179912-ALV-J-GD19, KJ179911-ALV-J-GD31) with nucleotide and amino acid identities of 98–100%; respectively. Moreover, Newvalley-2-EGYALVJ-env isolate is close similar to previous mentioned Chinese strains with nucleotide identity percentages of 98% and amino acid identity percentage 97%, 96%, 96%; respectively. This study confirmed that our two ALV-J isolates are not completely similar to the current Egyptian isolates. Also, ALV-J infection was continuously distributed in the breeders and considered one of the factors contributing to the tumor epidemics.