BMC Veterinary Research最新文献

Background: Vaccination of farmed salmonids has been an integral part of preventing infectious diseases in Norway's aquaculture industry. In Norway, vaccine usage is regulated by the government. There is a need to monitor vaccine usage for both regulatory and research purposes, at local and national scales. The Norwegian Veterinary Prescription Register (VetReg) is a national database that includes all prescriptions of medicines to animals dispensed by pharmacies and all medicines used for food producing animals by veterinarians. This study aimed to evaluate the quality of fish vaccination data reported to VetReg in 2016-2022. We considered the following attributes: completeness, validity, and timeliness. For external validation, we compared the data in VetReg to wholesaler statistics.

Results: Pharmacies reported fish vaccines to VetReg in a variety of quantity units, including doses and volumes, which required us to harmonize the data to a single unit. It was not possible to harmonize the quantity units for nine percent of the records, which were mainly bath vaccines reported in doses. We identified specific issues that required manual editing of the units of 1 percent of the records. We validated individual variables such as product codes and location identifiers using external registers. The 'number of animals' variable was inconsistent for 31 percent of the records. The coverage of vaccine data in VetReg ranged from 81 to 113 percent for the ten most sold vaccines in 2020-2022, as compared to wholesales statistics. For the timeliness, we found that 75 percent of the records were submitted within 25 days for all years.

Conclusions: Overall, we found that the fish vaccination data in VetReg was of sufficient quality to monitor injectable vaccine usage at hatcheries after 2020. We identified issues at the product level, with bath vaccines, and with single variables (number of animals, weight, and species). We recommend that quality can be improved by reporting all vaccines in volume rather than doses, reporting a single vaccine prescription per report, and including a deadline for pharmacies to report in the legislation.

Background: Saidi sheep are one of the most important farm animals in Upper Egypt, particularly in the Assiut governorate. Since they can provide meat, milk, fiber, and skins from low-quality roughages, sheep are among the most economically valuable animals bred for food in Egypt. Regarding breeding, relatively little is known about the Saidi breed. In mammals, the uterus is a crucial reproductive organ. Therefore, the purpose of this work was to provide further details on the histological, histochemical, and immunohistochemical analyses of superoxide dismutase 2 (SOD2), glutathione reductase (GR), and progesterone receptor alpha (PRA) as well as terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling assay (TUNEL) of the uterus during the follicular phase of estrous cycle in Saidi sheep. Thus, 11 healthy Saidi ewes (38.5 ± 2.03 kg weight) ranging in age from 2 to 5 years were used to examine the histological changes in the uterus.

Results: In Saidi sheep, the uterine histological and immunological picture during the follicular phase of the estrous cycle was characterized by epithelial and stromal proliferation and apoptosis. Leucocytic recruitment (lymphocytes, plasma, and mast cells) was also observed. Uterine gland adenogenesis, vascular angiogenesis, oxidative marker expression, and PRA expression in the muscles, stroma, and epithelium were the most noticeable features of the follicular phase.

Conclusion: This study provides new evidence of the role of PRA, SOD2, GR, and mast cells in controlling uterine epithelial proliferation and apoptosis in the Saidi sheep during the follicular phase of the estrus cycle. These findings have growing significance in understanding the key mechanisms that characterize successful reproduction and enhancing the fertility and reproductive efficiency in Saidi Sheep.

Background: Wild game meat has over the years gained popularity across the globe as it is considered a food source with high protein content, low fat content, and a balanced composition of fatty acids and minerals, which are requirements for a healthy diet. Despite this popularity, there is a concern over its safety as many species of wildlife are reservoirs of zoonotic diseases including those of bacterial origin, more so antibiotic-resistant bacteria.

Methods: This study aimed to describe the prevalence of antibiotic-resistant bacteria in mammalian wild game, following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines.

Results: The overall pooled prevalence of antibiotic resistance was established at 59.8% while the prevalence of multidrug resistance (MDR) was 17.2%. Resistance was reported in 32 wild game species and the meta-analysis revealed the highest prevalence of antibiotic resistance in Yersinia spp. (95.5%; CI: 76.8 - 100%) followed by Enterococcus spp. (71%; CI: 44.1 - 92%), Salmonella spp. (69.9%; CI: 44.3 - 90.0%), Staphylococcus spp. (69.3%; CI: 40.3 - 92.3%), and Escherichia coli (39.5%; CI: 23.9 - 56.4%). Most notably, resistance to highest priority, critically important antimicrobials, was recorded in all genera of bacteria studied. Additionally, a significantly higher prevalence of antibiotic resistance was observed in studies conducted in remote settings than those in the vicinity of anthropogenic activities, pointing to extensive contamination of wild habitats.

Conclusion: This review shows the presence of antibiotic resistance and the carriage of antimicrobial resistance (AMR) genes by bacteria isolated from mammalian wild game species. This is a cause for concern if critical steps to prevent transmission to humans from meat and meat products are not applied in the wild game meat production chain. The extensive occurrence of antibiotic resistance in the wild calls for expansion and adaptation of future AMR surveillance plans to include areas with various anthropogenic pressures including in sylvatic habitats.

This study aimed to evaluate alternative in vivo treatment trials using natural products for ectoparasitic infestation on Nile tilapia; these two products were not previously used in the treatment of parasitic fish diseases. So, a total of 400 Oreochromis niloticus (O. niloticus) fish measured 10-15 cm in length; 350 from a fish farm in (Kafr Elsheikh and 50 from Nile River (Al Bahr Al Aazam), Egypt. The examined fishes were 10-15 ± 0.5 cm long and weighed from 45 g ± 5. The collected fish were examined for different clinical abnormalities. Each part of the fish underwent a careful microscopic examination of mucous surrounding the skin; gills and fins. Two feed supplements were used experimentally to decrease mortality and treat fish against ectoparasites (Herb-All PARA-X^® and Herb-All CALM^®). Total mRNA was extracted from the gills of different examined groups. Glucose; nitric oxide; cortisol as well as lysozyme activity were assessed in all groups. The gills of the examined fish were collected for histopathological examination. Only, Dactyolgyrus sp. was recovered. The intensity of the parasite was counted per microscopic field. The treated groups showed low levels of the parameters compared to the control positive group. Up-regulation of both Tumor necrosis factor-α (TNF- α) and heat shock protein 70 (hsp-70) were detected in fins, gills, and skin in the infested tilapia. The treatment and prophylaxis significantly downregulated both genes in the studied organ in a dose-dependent manner. Recorded lesions which were scored according to their severity. In conclusion; following the use of those products, fish health has been greatly improved and that is indicated by findings of immune reactions as well as histopathology.

Background: Diatomite is a source of biologically available silicon but in feed industry its insecticide and anti-caking properties have been also widely recognized. The aim of the study was to evaluate the effect of dietary diatomite-bentonite mixture (DBM) supplementation on the quantitative and qualitative composition of the bacterial microbiome of the broiler chicken gut. The trial was carried out on 960 Ross 308 broiler chickens divided into 2 experimental groups throughout the entire rearing period lasting 6 weeks. The birds were fed complete granulated diets without (group C) or with DBM (group E) in an amount of 1% from the 11 day of life. Two nutritionally balanced diets were used, tailored to the age of the broilers: a grower diet (from day 11 to 34) and a finisher diet (from day 35 to 42 of life).

Results: Diatomite used in a mixture with bentonite significantly altered the microbiome. Restricting the description to species that comprise a minimum of 1% of all analyzed sequences, 36 species in group E (with diatomite) and 30 species in group C (without diatomite) were selected. Several bacteria species were identified in intestinal contents of chickens for the first time. Thirteen species occurred only in group E: Agathobaculum butyriciproducens, Anaerobutyricum hallii, Anaerobutyricum soehngenii, Blautia producta ATCC 27,340 = DSM 2950, Gordonibacter pamelaeae 7-10-1-b, Helicobacter pullorum NCTC 12,824, Lactobacillus crispatus, L. helveticus DSM 20,075 = CGMCC 1.1877, Mucispirillum schaedleri, Phascolarctobacterium faecium, Phocaeicola coprocola DSM 17,136, P. massiliensis, and Ruthenibacterium lactatiformans.

Conclusions: The findings highlight the intricate and potentially consequential relationship between diet, specifically diatomite-bentonite mixture supplementation, and gut microbiota composition.

Phytochemicals have been effectively used to enhance the growth and productivity of farm animals, while the potential roles of essential oils and their nano-emulsions are limited. This plan was proposed to investigate the impacts of orally administered moringa oil (MO) or its nano-emulsion (NMO) on the growth, physiological response, blood health, semen attributes, and sperm antioxidant-related genes in rams. A total of 15 growing Rahmani rams were enrolled in this study and allotted into three groups. The 1^st control group received a basal diet only and treated orally one mL of distilled water, while the 2^nd, and 3^rd groups received a basal diet and were orally treated with 1 mL of NMO or 2 mL of MO /head/day for 4 months, respectively. Growth, physiological response, blood health, semen quality, and antioxidant genes in sperm were assessed. The MO and NMO treatments had no significant effect on growth indices (final body weight and weight gain ) and physiological response (rectal temperature, pulse, and respiration rates) (P > 0.05). The NMO group had the lowest levels of MCV (mean corpuscular volume) (P < 0.05), while all treated groups produced higher levels of mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) compared to those in the control group (P < 0.05). Aspartate transferase (AST) and total cholesterol were significantly reduced in the MO and NMO groups, while total protein and glucose levels were significantly improved in NMO group (P < 0.05). Serum and seminal interstitial-cell-stimulating hormone (ICSH) levels were significantly improved (P < 0.0001) in the NMO group. Testosterone in serum and seminal plasma was significantly improved (P < 0.0001) in the MO group. Total antioxidant capacity (TAC) levels showed a tendency to increase in both the MO and NMO groups, but this increase was not significant compared to the untreated group (P > 0.05). On the other hand, the MO group exhibited lower levels of AST and malondialdehyde (MDA), while the alanine aminotransferase (ALT) levels were the lowest in the NMO group (P > 0.05). Mass motility, viability, membrane integrity and sperm concentration were significantly improved in the MO group (P < 0.0001) compared to the other groups. The NMO group had worse expressions of superoxide dismutase 1 (SOD1) compared to the control and MO groups. MO group significantly upregulated the catalase gene compared to the other groups (P < 0.001). The expression of Caspase-3 was highest in the group that received NMO compared to the other groups (P < 0.001). This study suggests that MO may serve as a novel therapeutic agent for improving the reproductive health in Rahmani rams.

Background: Elevated BHB levels are hypothesized to influence hepatic antioxidant enzyme expression and activity, contributing to oxidative response. However, the impact of BHB between 0.8 and 1.2 mmol/L on these mechanisms remains unclear. We hypothesized that elevated serum BHB levels would influence the hepatic expression of antioxidant genes (SOD1, SOD2, SOD3, and GPX3) and blood antioxidant enzyme activity, contributing to oxidative response. The primary objective was to evaluate the correlation between serum BHB levels, hepatic antioxidant gene expression, and blood antioxidant enzyme activity in high-yielding dairy cows during the postpartum period. The study involved 23 healthy high-yielding Holstein-Friesian dairy cows, divided into experimental (EXP, n = 12) and control (CONT, n = 11) groups based on serum BHB levels during the first three weeks postpartum. The EXP group maintained BHB levels between 0.8 and 1.2 mmol/L, while the CONT group remained below 0.8 mmol/L. All animals were monitored up to 9 weeks postpartum. This cohort study utilized weekly blood samples from 7 days prepartum to 9 weeks postpartum and liver biopsy samples from 4 to 7 weeks postpartum. Serum BHB concentrations, blood SOD and GSH-Px activities, and hepatic expression of SOD1, SOD2, SOD3, and GPX3 genes were analyzed.

Results: The EXP group exhibited a significant increase in hepatic SOD2 expression at 4 weeks postpartum (p < 0.05) and higher blood SOD activity at 6 and 7 weeks postpartum compared to controls. This suggests an oxidative activity response to elevated BHB levels. By week 7, hepatic SOD2 expression began to normalize, indicating a transient response or adaptation. No significant changes were observed in hepatic SOD1, SOD3, or GPX3 expression between groups.

Conclusion: Persistently high serum BHB levels in postparturient dairy cows significantly impact hepatic SOD2 expression and blood SOD activity. The specificity of this response, primarily involving SOD2, highlights the complex interplay between metabolic changes and oxidative mechanisms during the transition period. These findings underline the importance of BHB concentration monitoring and suggest potential reevaluation of current BHB thresholds for identifying at-risk cows. Furthermore, SOD2 could potentially serve as an early biomarker.

Background: Pseudorabies virus (PRV), porcine parvovirus (PPV) and porcine circovirus 3 (PCV3) are common in swine farms in China. Single infection or co-infection with PRV, PPV and/or PCV3 was difficult to distinguish between their clinical symptoms and pathological changes. Therefore, a quick and accurate detection method is needed for epidemiological surveillance, disease management, import and export control.

Methods: In the present study, we established a multiplex real-time PCR assay based on SYBR Green I for the simultaneous detection of PRV, PPV and PCV3 genomes.

Results: PRV, PPV and PCV3 were distinguished in the same sample by their different melting temperatures (Tm), with melting peaks at 90 °C for PRV, 84 °C for PPV and 80 °C for PCV3, respectively, and other non-targeted swine pathogens did not exhibit specific melting peaks. The assay showed a high degree of linearity (R²≧0.995), and the detection limits were 4.76 copies/μL for PRV, 3.67 copies/μL for PPV, 3.07 copies/μL for PCV3 and 1.87 × 10² copies/μL for the three mixed plasmids, respectively. In this research, 81 clinical samples from pig farms in nine different regions of Guangdong Province were used to evaluate this new method. The detection rate of the multiplex real-time PCR assay was higher than that of the conventional PCR assay.

Conclusions: This multiplex real-time PCR assay could be used as a diagnostic tool that is rapid, sensitive and reliable for the detection of co-infection of PRV, PPV and PCV3 as well as for molecular epidemiological surveillance.

Background: The proximity between people and their domestic animals with wild animal populations can result in the spread of diseases with a significant impact on public health. Infection by parasites in wildlife is considered an important bioindicator of the current state of ecosystems, and studying the epidemiology of these infections is essential for a better understanding of natural foci. However, research on parasites in southern Brazil, especially in Rio Grande do Sul (RS), is considered incipient. Therefore, in this study, we aimed to identify the parasitic fauna of wild animals in the southern region of RS through fecal parasitological diagnosis. We processed 82 fecal samples from wild animals - including birds, mammals, and reptiles - from cities within the microregion of Pelotas, using the Zinc Sulfate Centrifugal Flotation, Spontaneous Sedimentation and Oocyst Sporulation techniques.

Results: In 69.5% of the samples (93.1% of mammals, 47% of birds and 50% of reptiles), we found helminth eggs and/or protozoan cysts/oocysts, with strongylid-type eggs being the most frequent parasites (44.11%). Additionally, 64.9% of the positive samples were parasitized by at least one morphogroup with zoonotic agents (Taeniidae, Capillaria, Strongyloides, Spirometra, Lagochilascaris, Sarcocystis, Trichuris, Giardia, Ancilostomid, Physaloptera, Toxocara, Fasciola). We also recorded the first finding of Monocystis spp. in a Southern tamandua (Tamandua tetradactyla).

Conclusions: Thus, it was observed that the majority of the animals were parasitized and, consequently, susceptible to a wide range of pathogens of medical and veterinary interest, highlighting the importance of these hosts in the spread of parasites, especially those with zoonotic potential. However, the ecology of transmission and the role of these hosts in the life cycles of parasites should be further explored in other studies.

Background: Probiotics and essential oils feed supplements are widely used in the aquaculture sector. This study was conducted to evaluate the effects of dietary supplementation with probiotics, essential oils and their combination on growth performance, serum biochemical parameters, antioxidant capacity, resistance against Aeromonas veronii, and intestinal histomorphology of Nile tilapia (Oreochromis niloticus). A total of 360 O. niloticus fingerlings were randomly assigned to four groups (3 replicates/ group; each replicate contains 30 fish) based on the different dietary treatments. The first group was fed a basal control diet (G1), the second group was fed a basal diet supplemented with 0.015% probiotic (Klu-zetar^®) (G2), the third group was fed a basal diet with 0.015% essential oil (ACTIVO^®) (G3), and the fourth group was fed a basal diet mixed with 0.015% Klu-zetar^® and 0.015% ACTIVO^®, (G4) for 6 weeks. At the end of the trial fish were intraperitoneally injected with pathogenic bacteria Aeromonas veronii and the fish mortality rate was recorded for 7 days post infection.

Results: The results revealed that using probiotics and or essential oils in Nile tilapia diets improved growth performance, reduced oxidative stress, enhanced immunity, maintained intestinal integrity, and enhanced resistance to pathogenic infection (P ≤ 0.05).

Conclusions: It is concluded that the use of probiotics and/ or essential oils enhance the overall outcomes of Nile tilapia, so it is highly recommended to be used in aquaculture management.