Veterinary Research Forum

Abstract Respiratory infections are considered within the major constraints of animal production; viruses are the major causing pathogens. This study aimed to elucidate the prevalence of parainfluenza virus-3 (PIV-3), bovine viral diarrhea virus, and respiratory syncytial virus (RSV) in sheep and goats and the existence of co-infections. A total of 270 sheep and 220 goat pneumonic lung tissues were collected from slaughterhouses in four different areas. Enzyme-linked immunosorbent assay was used to detect the antigen of the three viruses, fluorescent antibody technique and polymerase chain reaction confirmed enzyme-linked immuno-sorbent assay positive results. Prevalence detected for PIV-3 was 11.10% in sheep and 9.50% in goats, pestivirus was 10.40% in sheep and 7.70% in goats, and RSV was 17.80% in sheep and 5.00% in goats. Detected co-infections were 5.60% for PIV-3 and pestivirus in sheep and 4.00% in goats and pestivirus and RSV was observed only in goats (1.40%). Co-infection of the three viruses was detected in only one goat sample (1.00%). The existence of the three viruses in sheep and goats was confirmed. To our knowledge, this is the first report of the co-infections of PIV-3, pestivirus, and RSV in sheep and goats in the studied areas.

Abstract Pseudorabies (PR), an infectious disease caused by PR virus (PRV), has had a significant impact the development of the swine industry in China. Moreover, the public threat posed by PRV has raised widespread concern, with over 30 documented cases of PRV infection in humans in China. Various vaccines have been developed to prevent and control PR in China, primarily including inactivated vaccines and attenuated live vaccines. However, the extensive use of attenuated live vaccines and the presence of the field PRV strain in pig farm may increase the likelihood of recombination. In this study, we isolated a PRV variant strain (designated HuN-YY) from a piglet that had been immunized with the HB-98 vaccine strain in Hunan province and explored its genetic and biological features. The results showed that the gE, TK and gD genes of HuN-YY exhibited the highest sequence similarity with those of PRV variants, while the gC gene showed high homology with classical PRV strains. In addition, HuN-YY strain exhibited similar replication features compared to those of HB-98 and variant strains. Its pathogenesis in a mouse model was significantly lower than that of the variant strain. Collectively, these results provide clear evidence of genomic recombination of the HuN-YY strain, which will offer guidance for the future prevention and control of PR.

Abstract Cisplatin (CS) is a broad-spectrum chemotherapeutic agent that causes serious adverse effects, such as cardiotoxicity, despite its potent anti-tumor efficacy. This study aimed to evaluate the cardioprotective effects of betaine in rats exposed to repeated low-dose CS administration using histopathological and immunohistochemical methods. Forty female Wistar albino rats were divided into four groups, including control, betaine, CS, and CS + betaine. Betaine (250 mg kg^-1) was administered orally on a daily basis for four weeks, while CS (8.00 mg kg^-1) was administered intraperitoneally once a week for the same duration. Cardiomyocytes were then examined using histopathological and immunohistochemical methods. The data were analyzed using one-way analysis of variance and Tukey tests. Histopathological analysis revealed cardiomyocyte disorganization, myofibril loss, and increased eosinophilia in the CS group. Betaine treatment partially prevented CS-induced histological damage, contributing to the cardiac muscle structure preservation. Immunohistochemical analyses demonstrated a significant increase in transforming growth factor-beta and interferon gamma expressions in the CS group, whereas betaine administration reduced transforming growth factor-beta levels. Interleukin 6 expression was lower in the CS + betaine group compared to the CS group. No significant differences were observed between groups regarding Interleukin -1β expression. These findings suggest that betaine may have protective effects against CS-induced cardiotoxicity. Its anti-inflammatory properties appear to mitigate cardiomyocyte damage.

Abstract Doxorubicin (DOX), as a potent anti-cancer agent, exerts side effects in vital organs. Various chemical compounds with tissue protective properties are used to prevent the side effects of DOX. This study was planned to investigate the effects of histidine (HIS) and N-acetylcysteine (NAC) ​​on DOX-induced acute kidney injury. The possible mechanisms were followed by determining the histopathological changes of the kidney along with the biochemical alterations of the blood and kidney tissue. Forty-eight rats were divided into eight groups of six animals each to receive normal saline and DOX after alone and combined treatments with HIS and NAC. The DOX at a single dose of 15.00 mg kg^-1 was intraperitoneally injected on day one. The separate and combined intraperitoneally injections of HIS and NAC at a similar dose of 100 mg kg^-1 were began 30 min after DOX administration and continued for seven consecutive days. The DOX increased kidney weight and caused congestion, hemorrhages and degeneration in kidney tissue. It also increased serum urea and creatinine concentrations and kidney tissue levels of malondialdehyde, tumor necrosis factor-alpha and caspase-3, and decreased superoxide dismutase activity in this tissue. Separate and combined treatments with HIS and NAC improved all the above-mentioned effects of DOX. The restoring effects of the combined treatment were more prominent than the effect of amino acids alone. It was concluded that anti-oxidative, anti-inflammatory and anti-apoptotic mechanisms might be related to the tissue protective effects of HIS and NAC against DOX-induced acute renal injury.

Abstract Trichinella britovi is a species circulating in Iran and has already been observed in wild and domestic carnivores. The present study aims to determine the occurrence of Trichinella species in Iran's most important provinces, including the northern, northeastern, and northwest regions. In total, 93 carcasses of golden jackals, collected due to road accidents between 2019 and 2022, have been obtained from Ardabil, Mazandaran, Golestan, North Khorasan, and Khorasan Razavi provinces, Iran. Genomic DNA (four positives out of 93 carcasses) from each Trichinella genotype was amplified in a multiplex polymerase chain reaction (PCR) reaction. To confirm the multiplex PCR results, the sequences of the PCR products with cytochrome oxidase subunit I were sent to a reference laboratory within the European Union. Bioinformatics software was used to verify the sequencing results of primer fragments and to compare and analyze the results obtained with the sequences stored in the NCBI genetic database. Following multiplex PCR amplification, a two-band pattern was observed. Trichinella britovi larvae displayed the expected band pattern of 127 bp and 253 bp. The PCR products amplified using primers specific for the cytochrome oxidase subunit I gene showed 861 base pair bands in all four samples analyzed. The obtained sequences of cytochrome oxidase subunit I from all four individual muscle larvae had 100% identical haplotypes except for one nucleotide transversion in one sequence. As a result of this study, valuable insights into T. britovi prevalence and phylogenetic distribution among Iranian golden jackals have been gained in terms of prevalence and phylogenic distribution.

Abstract Hepatitis E virus (HEV) is a zoonotic pathogen that can cause acute viral hepatitis in both humans and animals. Some animals, such as swine, rabbits, cattle, and sheep are recognized as primary reservoirs of HEV. Recently, HEV has emerged as a significant public health concern in both industrialized and developing countries. Up to now, there is no information about zoonotic sources and prevalence of HEV in wild and domestic animals in Iran. This cross-sectional study aims to determine the prevalence of HEV. Multi-stage cluster sampling approach was used to collect 400 fecal swabs and 400 milk samples between September and February 2022. These samples were collected from rural cattle dairy farms in northern Iran. The viral genome was extracted, and semi-nested reverse transcription polymerase chain reaction was used to detect the HEV RNA genome. The overall estimated herd-level prevalence of HEV was found to be 6.25% (5/80, 95.00% CI: 2.06 - 13.99%). Among the 400 fecal and 400 milk samples obtained from 80 farms, the prevalence of HEV was 3.75% (3/80, 95.00% CI: 0.78 -10.57%), and 2.50% (2/80, 95.00% CI: 0.80 - 30.74%), respectively. Positive fecal samples were detected in Abbas-abad and Amol cities, while positive milk samples were found in Tonekabon City. Based on our findings, Hepatitis E is present in the cattle population of Mazandaran province, Iran. Further, more in-depth investigations are recommended due to the zoonotic nature of this disease. It is crucial to consider control and preventive measures in order to mitigate the spread of HEV.

Abstract Bovine ephemeral fever (BEF) is a debilitating disease of cattle and water buffaloes. Bovine ephemeral fever viruses (BEFVs) form four phylogenetic lineages including the Middle East, East of Asia, Australia and Africa, while the exotic viral strains have also been detected in different geographic areas. We characterized eight BEFVs from different regions of Iran during a period of seven years from 2015 to 2022. Sequencing the entire length of the G gene, the BEFVs were classified in the Middle Eastern lineage with the maximum of 99.73% and minimum of 97.30% nucleotide identity. The all Iranian and Turkish BEFVs detected during the large epizootic in 2020 were clustered phylogenetically together. However, no amino acid variation was observed between the Iranian viruses detected in 2020 and those identified before 2020 in the Middle Eastern lineage suggesting that host, environmental and other genetic factor (s) might have involved in occurrence of the epizootic in 2020. Two BEFVs detected during 2022 outbreak from Kermanshah and Narmashir in the west and east of Iran, respectively, were clustered in two distinct groups as a novel amino acid substitution H51Y in the epitope G3 was also identified in Kermanshah 2022 sequence. These results imply that the Middle Eastern lineage replaced the previously circulated East Asian BEFVs in Iran during 2012 to 2013 and also signify the emergence of new BEFVs due to the intra-lineage evolution. Continuous monitoring of the circulating viruses and identifying the potential vector (s) and its biology help better understand epizootiology of BEFV in the high-risk region.

Abstract Spinal cord injury (SCI) results in the demise of neural and glial cells, as well as extensive neuro- inflammation. Hydrogel formulation for prolonged release of melatonin (Mel) has demonstrated enhanced effectiveness and safety. In this study, SCI was induced in rats by contusion at the T₉ vertebrae. Chitosan (CH) /Mel hydrogel was fabricated and characterized using scanning electron microscopy (SEM) and Fourier transform infra-red to examine its specific effects on the apoptotic and histopathological markers of SCI. The scanning electron microscopy images revealed the presence of porosity in the CH/Mel hydrogel. Forty male Wistar rats were randomly divided into five groups (n = 8), including sham, control (SCI-induced treated locally with 100 µL CH hydrogel), and groups 3, 4, and 5 (treated locally immediately after SCI induction with 100 µL CH hydrogel containing 50.00, 100, and 200 mg kg^-1 Mel, respectively). The CH/Mel hydrogel at a dose of 25.00 mg mL^-1 significantly increased cell viability in the U87 cell line after 24 hr of exposure. However, at 48 and 72 hr after exposure, Bax and Bcl2 expressions were significantly increased and reduced in the SCI group, respectively, and CH/Mel hydrogel could alleviate their expressions, especially in higher doses. In addition, S100 protein expression was up-regulated in the SCI group. However, CH/Mel hydrogel down-regulated it in a dose-dependent manner. The histopathological findings demonstrated that CH/Mel hydrogel dramatically improved SCI outcomes, like vacuolar degeneration, necrosis, and severe cystic and axonal degenerations. In conclusion, CH/Mel hydrogel induced neuroprotection and it had the potential to be used as a therapeutic agent for the treatment of SCI.