BMC Veterinary Research最新文献

Background: Mitochondrial biogenesis (MB) induction has recently emerged as potential therapeutic approaches in kidney pathology and the mitochondria-targeted therapies should be investigated to improve treatment of animals with kidney diseases. This study aimed to investigate the effects of MB induction with sildenafil citrate on the cGMP/NO pathway, glomerular filtration, and reduction of kidney damage and fibrosis (TGF-β/SMAD pathway) in cats with acute on chronic kidney disease (ACKD). Thirty-three cats were divided into the non-azotemic (healthy) group (n:8) and the ACKD group (n:25), comprising different breeds, sexes, and ages. Sildenafil citrate was administered to the non-azotemic and ACKD groups (2.5 mg/kg, PO, q12 hours) for 30 days. Serum and urine NO, MDA, NGAL, KIM-1, TGF-β1, IL-18, FGF 23, PGC-1α and cGMP concentrations were measured.

Results: Serum cGMP concentrations increased (P < 0.05) in the non-azotemic group during the 2^nd (median 475.99 pmol/mL) and 3^rd (median 405.01 pmol/mL) weeks of the study, whereas serum cGMP concentrations decreased in the ACKD group during the 4^th(median 188.52 pmol/mL) week compared to the non-azotemic group (P < 0.05). No difference was observed in serum biomarker concentrations except NO, which increased in the 4^th week (P < 0.05). The urinary concentrations of NO, MDA, PGC-1α, TGF-β1, NGAL, KIM-1, IL-18, and FGF 23 in the ACKD group were found to be higher compared to those in the non-azotemic group from the 1^st to the 4^th week (P  < 0.05). In the ACKD group, the urine PGC-1α concentration in the 2^nd (median 6.10 ng/mL) week was lower compared to that in the 0 and 1^st (median 7.65 and 7.21 ng/mL, respectively) week, and the NO concentration in the 3^rd (median 28.94 µmol/mL) week was lower than that in the 0^th (median 37.43 µmol/mL) week (P < 0.05).

Conclusions: While sildenafil citrate has been determined to induce a low level of MB and to have a beneficial effect on glomerular filtration, it is observed to be ineffective in mitigating renal damage and fibrosis via the TGF-β/SMAD pathway in cats with ACKD.

Background: Koala retrovirus (KoRV), a major pathogen of koalas, exists in both endogenous (KoRV-A) and exogenous forms (KoRV-A to I and K to M) and causes multiple disease phenotypes, including carcinomas and immunosuppression. However, the direct association between the different KoRV subtypes and carcinogenesis remains unknown. Differentially expressed gene (DEG) analysis of peripheral blood mononuclear cells (PBMCs) of koalas carrying both endogenous (KoRV-A) and exogenous (KoRV-A, B, and C) subtypes was performed using a high-throughput RNA-seq approach. PBMCs were obtained from three healthy koalas: one infected with endogenous (KoRV-A; Group I) and two infected with exogenous (KoRV-B and/or KoRV-C; Group II) subtypes. Additionally, spleen samples (n = 6) from six KoRV-infected deceased koalas (K1- K6) and blood samples (n = 1) from a live koala (K7) were collected and examined to validate the findings.

Results: All koalas were positive for the endogenous KoRV-A subtype, and eight koalas were positive for KoRV-B and/or KoRV-C. Transcription of KoRV gag, pol, and env genes was detected in all koalas. Upregulation of cytokine and immunosuppressive genes was observed in koalas infected with KoRV-B or KoRV-B and -C subtypes, compared to koalas infected with only KoRV-A. We found 550 DEG signatures with significant (absolute p < 0.05, and absolute log₂ Fold Change (FC) > 1.5) dysregulation, out of which 77.6% and 22.4% DEGs were upregulated (log₂FC > 1.5) and downregulated (log₂FC <  - 1.5), and downregulated (log₂ FC <  - 1), respectively. We identified 17 unique hub genes (82.3% upregulated and 17.7% down-regulated), with KIF23, CCNB2, POLR3F, and RSL24D1 detected as the potential hub genes modified with KoRV infection. Real-time RT-qPCR was performed on seven koalas to ascertain the expression levels of four potential hub genes, which were subsequently normalized to actin copies. Notably, all seven koalas exhibited distinct expression signatures for the hub genes, especially, KIF23 and CCNB2 show the highest expression in healthy koala PBMC, and POLR3F shows the highest expression in koala with lymphoma (K1).

Conclusion: Thus, it can be concluded that multiple KoRV subtypes affect disease progression in koalas and that the predicted hub genes could be promising prognostic biomarkers for pathogenesis.

Background: Anthelmintic resistance (AR) is a global threat to grazing livestock farming. In Italy, anthelmintic efficacy remains high compared to other European countries, but many parts of the country haven't been investigated yet. Local veterinary practitioners from Trentino and Veneto regions reported suspected inefficacy towards anthelmintic drugs in some of their farms, prompting a study on AR in sheep and goat farms of northern Italy. The study aimed to assess anthelmintic effectiveness using genus-specific faecal egg count reduction tests (FECRT), to detect differences in treatment response among nematode genera involved in the infection.

Results: Twelve farms (6 sheep and 6 goat farms) were included based on clinical suspicion of AR. Treatments were carried out with either benzimidazoles (BZ) or macrocyclic lactones (ML) Treatment was effective in 3/6 goat trials, with reduced effectiveness to BZ in two farms and to ML the last one. In sheep farms (6/6), effectiveness was consistently and more severely insufficient. Ineffectiveness was particularly high towards Haemonchus contortus, while Oesophagostomum/Chabertia maintained susceptibility in nearly all trials. Trichostrongylus/Teladorsagia exhibited intermediate results.

Conclusions: This study reveals diminished efficacy of both BZ and ML in small ruminant farms in north-eastern Italy, an area previously lacking data on the topic, except for goats in South Tyrol. Variability in treatment responses among nematode genera support suspicions of AR, and further concerns are raised by the prevalence of treatment ineffectiveness against the highly pathogenic Haemonchus contortus. This finding underscores the urgent need for comprehensive AR monitoring in the area and improved management practices to prevent further resistance development and protect livestock health.

Background: Hemoplasma infections in cattle are caused by Mycoplasma wenyonii and Candidatus Mycoplasma haemobos and induce asymptomatic or chronic infections but occasionally lead to life-threatening hemolytic anemia. Despite the global distribution of bovine hemoplasmas, information regarding their transmission vectors and prevalence is still lacking in the Republic of Korea. Therefore, this study aims to investigate the infection rate of bovine hemoplasma in cattle and houseflies and to assess the risk factors associated with hemoplasma infection in cattle.

Methods: Overall, 376 blood samples were collected from Korean indigenous cattle (male, 10-13 months old), along with 2,690 houseflies (Musca domestica) from the same farm where the cattle were raised. PCR assays targeting the 16S rRNA gene were performed to detect hemoplasmas, and positive samples were sequenced.

Results: The infection rate of bovine hemoplasmas was 50.8% (191/376) in cattle and 7.4% in pooled houseflies. Among cattle, 18.6% (70/376) and 20.0% (75/376) tested positive for M. wenyonii and Candidatus M. haemobos, respectively. Conversely, in houseflies, Candidatus M. haemobos was more frequently detected (5.9%) than M. wenyonii (0.7%). Co-infection was 12.2% (46/376) in cattle and 0.7% in flies. Furthermore, hemoplasma infection was significantly associated with the grazing experience of their dams. Cattle born to cows with grazing experience exhibited a higher risk for M. wenyonii infection (odds ratio [OR] = 1.62; 95% confidence interval [CI]: 1.03-2.55; P = 0.045), whereas these cattle had a lower risk for Candidatus M. haemobos infection (OR = 0.32, 95% CI: 0.19-0.74; P = 0.000) than animals born to cows without grazing experience. The sequences obtained from houseflies were confirmed as Candidatus M. haemobos, which displayed high similarity (98.2-100%) to those from cattle obtained in this study.

Conclusions: To our knowledge, this study represents the first report of bovine hemoplasmas identified in houseflies. This molecular evidence suggests that houseflies may be possible vectors for Candidatus M. haemobos.

Background: Antimicrobial resistance (AMR) is a global concern impacting both humans, animals and their environment. The use of oral antimicrobials in livestock, particularly in pigs, has been identified as a driver in the selection of AMR bacteria. The aim of the present study was to evaluate the effects of a single intramuscular (IM) dose of marbofloxacin (8 mg/kg) on Enterobacteriaceae and E. coli populations, as well as on fluoroquinolone resistance within the fecal microbiota of pigs. Twenty healthy pigs, 60-days old, were divided into two groups: a treated group (n = 13) and a control group (n = 7) and were monitored over a 28-day experimental period. Fecal samples were collected from all animals for the isolation of E. coli and Salmonella strains. The minimum inhibitory concentration (MIC) of marbofloxacin for the isolates recovered on MacConkey agar supplemented with 1 or 4 µg/mL of marbofloxacin and for some generic E. coli isolates (recovered from MacConkey agar not supplemented with marbofloxacin) was determined using the broth microdilution method. Genomic DNA was extracted from the confirmed bacterial strains and sequenced using the Sanger method to identify mutations in the quinolone resistance determining regions (QRDRs) of the gyrA and parC genes.

Results: The single IM administration of marbofloxacin resulted in a significant decrease in Enterobacteriaceae and E. coli fecal populations from days 1 to 3 post- treatment. No Salmonella isolates were detected in either group, and no marbofloxacin-resistant E. coli isolates were identified. The MIC of the selected generic E. coli strains (n = 100) showed an increase to up to 0.5 µg/mL between days 1 and 3 post-treatment but remained below the clinical breakpoint of marbofloxacin resistance (4 µg/mL). Sequencing of these isolates revealed no mutations in gyrA and parC genes.

Conclusions: The present study showed that this dosing regimen of marbofloxacin significantly decreases the fecal shedding of Enterobacteriaceae and E. coli populations in pigs, while limiting the selection of marbofloxacin-resistant E. coli isolates. These findings warrant validation in sick pigs to support the selective use of this antibiotic solely in cases of clinical disease, thereby minimizing the reliance on conventional (metaphylactic) group treatments in pigs.

Background: Nutritional interventions with natural antioxidants can provide a pragmatic solution for modifying hens' performance and maintaining oxidative stability of eggs during storage. Quercetin is the most abundant flavonoids with potent antioxidant and immune stimulant activities. The concept of incorporating of quercetin, as potent antioxidant and immunostimulant, into effective nano-carriers (QNPs) has promoted their bioavailability and stability thus, their effectiveness for the first time were assessed on laying hens' performance and immunity, eggs quality during storage. Four hundred 12-weeks-old Hy-line brown laying hens were distributed to four experimental groups: control group fed basal diets, and other 3 groups fed basal diets fortified with 100, 200 and 300 mg/kg QNPs for 60 weeks.

Results: Laying performance and quality of laid eggs were improved as expressed by elevated laying rate, egg mass %, eggs weight and yolk weight in QNPs200 and 300. Fortification of QNPs300 remarkably decreased layers serum total cholesterol concurrently with decreased egg yolk saturated fatty acids and cholesterol while increased polyunsaturated fatty acids. Over- 45 days storage period, QNPs enhanced phospholipids, total phenolics and flavonoids, total antioxidant activity (T-AOC) simultaneous with decreased MDA content in eggs. Furthermore, enhanced immune response was detected in both in serum and intestine of QNPs fed hens as reflected by higher lysozymes activity, IgM, IgG and phagocytic index and demotion of NO together with AvBD 6-12, IL-10, IgM and ATg 5-7-12 upregulation and downregulation of IL-1β and TNF-α especially at QNPs200 and 300. Intestinal redox balance was modified via decreasing H₂O₂ and MDA simultaneous with upregulation of catalase, SOD, GSH-Px, HO-1 and NQO1 in groups fed higher doses of QNPs.

Conclusions: QNPs supplementation provides a new nutritional strategy towards increasing hen performance, fortification of eggs with natural antioxidants that prevents egg quality deterioration during storage.

Background: Due to the adverse effects of industrial chemicals and their carcinogenicity and toxicity for humans, the debates have increased on using natural preservatives. This study was conducted to investigate the inhibitory effect of pure nisin and nisin nanoparticles (nisin NPs) against Aspergillus flavus in vivo by inoculation in laboratory-manufactured Ras cheese. A novel, safe, and natural approach of nanoprecipitation using acetic acid was employed to prepare nisin nanoparticles. The prepared NPs were characterized using zeta-sizer, FTIR, and transmission electron microscopy (TEM). Furthermore, the cytotoxicity of nisin NPs on Vero cells was assessed. The minimum inhibitory concentrations (MICs) of nisin and its nanoparticles were determined in vitro against A. flavus isolates using the agar well-diffusion method. The sensory evaluation of manufactured Ras cheese was conducted over a 60-day storage period.

Results: The obtained results showed a strong antifungal activity of nisin NPs (0.0625 mg/mL) against A. flavus strain in comparison with pure nisin (0.5 mg/mL). Notably, the count decreased gradually by time from 2 × 10⁸ at zero time and could not be detected at the 7th week. The count with pure nisin decreased from 2 × 10⁸ at zero time and could not be detected at the 10th week where it's enough time to produce aflatoxins in cheese. The MICs of nisin and nisin NPs were 0.25 and 0.0313 mg/mL, respectively. Nisin NPs used in our experiment had good biocompatibility and safety for food preservation. Additionally, the sensory parameters of the manufactured Ras cheese inoculated with nisin and nisin NPs were of high overall acceptability (OAA).

Conclusions: Overall, the results of this study suggested that adding more concentration (˃0.0625 mg/mL) from nisin nanoparticles during the production of Ras cheese may be a helpful strategy for food preservation against A. flavus in the dairy industry.

Background: Nanotechnology has the potential to reduce drug dosage while increasing efficacy; thus, the current work intends to synthesize diclazuril nanoemulsion and assess its performance against experimental coccidiosis in broilers.

Methods: Diclazuril nanoemulsion (DZN) was formulated and characterized by zeta seizer and zeta potential. The formulated DZN was evaluated in vivo against Eimeria tenella infected chicks. DZN and DZ were used in 2 programs; therapeutic and prophylactic. A total of 210 one-day-old broiler chicks were distributed equally into six groups. The controls were negative uninfected untreated and positive infected untreated (G1 & G2). Therapeutic groups (G3 & G4) treated by DZ and DZN after appearance of the clinical signs of coccidiosis and continued for 5 days. Prophylaxis groups (G5 & G6) received DZ and DZN at 3 days before challenge and continued for 5 days after infection. The treatments dosages were 10 mg/mL for DZ of commercial origin and 2.5 mg/mL for the prepared DZN. All groups (except negative control) orally infected then followed up for clinical signs of coccidiosis, mortality rate, oocysts count, performance, hematological and biochemical parameters in addition to histopathological lesions.

Results: The therapeutic groups showed that both treated groups (DZ and DZN) revealed similar results including good body weight gain, a low lesion caecal score, a low daily and total oocyst shedding count, and a low mortality rate. Regarding the biochemical parameters, all parameters were affected during infection then restored after the 12th day post infection. However, in the prophylactic groups, showed mild clinical signs and the blood pictures and biochemical parameters were nearly like the control negative without infection.

Conclusion: DZN at a quarter dose of standard DZ produced the same outcomes as DZ at 10 mg/mL. Furthermore, DZN does not impair the typical safety of diclazuril in treated chicks.

Background: Mycoplasma bovis is a global pathogen of cattle but was detected for the first time in New Zealand in 2017, triggering a response under their Biosecurity Act as an "unwanted organism". Following a lengthy eradication campaign, the Ministry of Primary Industries (MPI) now requires all bovine semen destined for export to New Zealand to be screened with an M. bovis-specific real-time PCR (rtPCR) compliant with amended import health standard (IHS) test requirements aimed at preventing the accidental importation of M. bovis. The standard stipulates that semen samples cannot be centrifuged prior to DNA extraction. To comply with these strict requirements, one of the listed tests was validated together with different DNA preparation steps and compared with existing in-house procedures. DNA was extracted from semen straws using the current in-house semi-automated platform procedures for processing culture, tissue and body fluid sample submissions and was compared with the stipulated test requirements. DNA from centrifuged and unspun semen samples spiked with M. bovis was also compared.

Results: The rtPCR had a sensitivity and specificity of 100% (95% confidence interval = 79-100% and 74-100%, respectively) when testing DNA from other Mycoplasma species or bovine semen spiked with the latter, with a high level of repeatability for within- and between- run replicates. The consistent limit of detection was 0.001 pg/µl M. bovis DNA and between 5.3 × 10² and 7.5 × 10² CFU/ml M. bovis when artificially spiked in semen. DNA extracted using the KingFisher Flex was detected with lower Cq values than the Maxwell 16, but the comparable improvements in sensitivity were mainly associated with non-centrifuged samples (p < 0.001). None of the procedures tested impeded the detection sensitivity of M. bovis in the presence of competitor organisms Acholeplasma laidlawii, Mycoplasma bovigenitalium and Ureaplasma diversum, confirming M. bovis specificity of the polC target.

Conclusions: Under the experimental conditions applied, this rtPCR test efficiently detected M. bovis in extended bovine semen straw samples from DNA extracted using both semi-automated extraction platforms, irrespective of prior centrifugation of extended semen.

Background: Canine mammary tumours (CMT) are among the most common types of tumours in female dogs. Diagnosis currently requires invasive tissue biopsies and histological analysis. Tumour cells shed extracellular vesicles (EVs) containing RNAs and proteins with potential for liquid biopsy diagnostics. We aimed to identify CMT subtype-specific proteome profiles by comparing the proteomes of EVs isolated from epithelial cell lines derived from morphologically normal canine mammary tissue, adenomas, and carcinomas.

Methods: Whole-cell protein lysates (WCLs) and EV-lysates were obtained from five canine mammary cell lines: MTH53A (non-neoplastic); ZMTH3 (adenoma); MTH52C (simple carcinoma); 1305, DT1406TB (complex carcinoma); and their proteins identified by LC-MS/MS analyses. Gene Ontology analysis was performed on differentially abundant proteins from each group to identify up- and down-regulated biological processes. To establish CMT subtype-specific proteomic profiles, weighted gene correlation network analysis (WGCNA) was carried out.

Results: WCL and EVs displayed distinct protein abundance signatures while still showing the same increase in adhesion, migration, and motility-related proteins in carcinoma-derived cell lines, and of RNA processing and RNA splicing factors in the adenoma cell line. WGCNA identified CMT stage-specific co-abundant EV proteins, allowing the identification of adenoma and carcinoma EV signatures not seen in WCLs.

Conclusions: EVs from CMT cell lines exhibit distinct protein profiles reflecting malignancy state, allowing us to identify potential biomarkers for canine mammary carcinomas, such as biglycan. Our dataset could therefore potentially serve as a basis for the development of a less invasive clinical diagnostic tool for the characterisation of CMT.