Iranian journal of veterinary research最新文献

Background: Timely diagnosis of brucellosis is the starting point for effective programs to control brucellosis in humans and animals. Aims: This study aimed to detect Brucella infection in milk samples from livestock in Famenin, an endemic region of western Iran, using a milk ring test and molecular techniques.

Methods: In this cross-sectional study, 738 raw milk samples were randomly collected from cattle, sheep, and goats. Milk samples were screened using the milk ring test (MRT). In addition, polymerase chain reaction (PCR) method was applied to detect Brucella spp. in all MRT-positive samples. DNA from the milk samples was extracted and used for PCR using the BCSP31 and IS711 loci.

Results: Of the samples tested using MRT, 46 (6.23%, 95% CI: 2.83-9.63%) yielded positive results. Of the 46 seropositive samples, 42 (91.30%) were from sheep and 4 (8.70%) were from goats, while no bovine samples had positive MRT results. PCR analysis confirmed that 78.26% (36/46) of MRT-positive samples belonged to the genus Brucella. Furthermore, 83.33% (30/36) of the confirmed samples were identified as B. melitensis, while 16.66% (6/36) were identified as B. abortus.

Conclusion: The results obtained from MRT evaluation of milk samples did not align entirely with the findings of the molecular examinations. The PCR method has minimal biological contamination and high sensitivity and accuracy, especially for determining Brucella species. Raw milk should be routinely assessed for Brucella contamination. This work is necessary to identify hidden infections and break the chain of transmission of brucellosis.

Background: Escherichia coli is a major cause of poor microbial quality of milk, often resulting from unhygienic milk handling. Milk contamination poses public health concerns. Shiga toxin-producing Escherichia coli (STEC) strains in food products, particularly milk, is a critical concern for public health. Limited information exists on the detection of non-O157 E. coli pathotypes in milk sold by local processors in Nigeria.

Aims: This study aimed to explore the diversity of non-O157 STEC isolates found in commercially available milk in Kwara State, Nigeria, to find the genetic diversity and potential risks associated with these strains.

Methods: A subgroup of 18 representative non-O157 STEC isolated from milk samples (n=1225) was selected for whole genome sequencing (WGS) analysis.

Results: Four novel sequence types (ST): ST398, ST540, ST1727, and ST9891 of non-O157 E. coli involving five serotypes: O176:H30, O176:H20, O8:H20, O21:H45, and O22:H7, carrying variable proportions of virulence factors, antimicrobial resistance genes, and plasmids, were identified.

Conclusion: This investigation contributes valuable data to the ongoing efforts to ensure food safety and prevent the transmission of E. coli strains through dairy products. The findings have implications for public health policies and food quality standards in Kwara State, Nigeria. Improved hygienic practices during milk handling are recommended.

Background: In acute alkali corneal burns, the routine treatment protocol includes suppressing inflammation using corticosteroids. In recent years, there has been a growing interest in the role of insulin in wound healing research due to its remarkable positive effects.

Aims: The present study aimed to compare the healing effects of dexamethasone -the conventional approach- and NPH-insulin on alkali corneal burns.

Methods: An alkali corneal burn was created using Ca (OH)₂ in all subjects. One group (n=6) was treated with an ophthalmic ointment containing dexamethasone (group I), and another group (n=6) was treated with an insulin ointment (group II). The control group (n=6) received no treatment (group III). Clinical changes in the corneal burn areas were monitored on days 3, 7, 14, and 21. The animals were euthanized on day 21. The excised corneas were examined for histopathological, immunohistochemical, and biochemical changes.

Results: A more successful clinical recovery graph was drawn for group II. Particularly, a significant (P<0.05) improvement was detected in group II on day 21. The highest positivity in MMP-9 corneal staining was found in group I. Group II had a significant (P<0.05) increase in total antioxidant capacity (TAC) values. The treatment groups showed a significant (P<0.05) decrease in total oxidant content (TOC) values and a significant (P<0.05) increase in reduced glutathione (GSH) levels as compared with the control group.

Conclusion: Topical NPH-insulin provided rapid and uncomplicated clinical recovery of alkali corneal burns. Insulin and dexamethasone showed similar effects like increased antioxidant molecules and decreased oxidant substances which indicated that insulin may prevent free radical formation in the cornea.

Background: Dermatological infections in dogs are challenging to treat due to antibiotic resistance, which leads to longer recovery time and the need for stronger antibiotics. Aims: This study was undertaken to determine the prevalence of antimicrobial resistance in coagulase-positive staphylococcal isolates from pyoderma infection in dogs. This study also aimed to identify isolates with methicillin-resistance and multidrug resistance.

Methods: 73 coagulase-positive staphylococci isolated from varying degrees of canine pyoderma cases. The samples were analyzed for the presence of Staphylococcus spp. using polymerase chain reaction (PCR) and resistance against antibiotics was studied by antimicrobial profile, minimum inhibitory concentration (MIC), and PCR on isolated bacteria.

Results: Out of 75 bacterial isolates identified, 73 isolates were confirmed as Staphylococcus species by PCR. A higher percentage of antibiotic resistance was observed against penicillin-G (46.27%), followed by amoxiclav (38.81%), enrofloxacin (32.84%), cefpodoxime, oxytetracycline (28.36% each), levofloxacin (26.86%), and co-trimoxazole (22.39%). 29 (49.15%) S. pseudintermedius, three (50.00%) S. schleiferi subsp. coagulans, and two (100%) S. aureus isolates exhibited multidrug resistance. However, one (1.49%) isolate (S. pseudintermedius) revealed low-level mupirocin resistance in the E-test. Also, 12 (20.34%) methicillin-resistant Staphylococcus pseudintermedius (MRSP), one (16.67%) methicillin-resistant S. schleiferi subsp. coagulans (MRSS) and one (50%) methicillin-resistant S. aureus (MRSA) were reported using PCR.

Conclusion: This study helps to understand the increased level and pattern of resistance in coagulase-positive staphylococci isolated from different types of canine pyoderma cases.

Background: There is a scarcity of data regarding the ultrasonographic characterization of tendons and ligaments in the distal limbs of donkeys.

Aims: To determine ultrasonographic characteristics of normal tendons and ligaments at the palmar/plantar aspect of the cannon region in Egyptian donkeys.

Methods: B-mode ultrasonography was conducted for the proposed tendons and ligaments in 12 clinically normal donkeys. Targeted structures were examined using transverse and longitudinal scans and evaluated in shape, echogenicity, echogenic pattern, fiber alignment pattern, and cross-sectional area (CSA).

Results: Using transverse scan, the sonographic shapes of tendons and ligaments of metacarpal and metatarsal regions were determined. Upon examining different levels of each region, specific ligaments, not tendons, were present only at the higher levels. The echogenicity of ligaments and tendons was either similar or variable across different levels. All tendons and ligaments displayed homogeneous echogenicity except for the suspensory ligament. In the longitudinal scan, tendons maintained linear and parallel fiber alignment along examination levels. Conversely, ligaments displayed mostly inconstant fiber patterns (linear/crimp). There was a statistically significant (P<0.05) difference in CSA of tendons and ligaments between certain levels within metacarpal and metatarsal regions. Upon comparing metacarpal and metatarsal regions, there were distinct variations in some ultrasonographic characteristics of the same tendons and ligaments.

Conclusion: This study established the ultrasonographic features of normal tendons and ligaments at the palmar/plantar aspect of the cannon region in donkeys (Equus asinus). These ultrasonographic data can be a reference guide when cannon region lameness is suspected.

Background: Brucella outer membrane proteins (OMPs) are highly immunogenic, and lipopolysaccharides (LPS) are also considered significant antigens, making them potential candidates for subunit vaccines.

Aims: To investigate the effects of Brucella OMPs and LPSs on mouse bone marrow-derived dendritic cells (BMDC) activation and T-lymphocyte proliferation.

Methods: BMDC were isolated and cultured in vitro, and subsequently co-cultured with Brucella recombinant proteins (rOMP10, rOMP19, rBP26, rOMP25, and rOMP31), as well as smooth LPS (S-LPS) or rough LPS (R-LPS). The expression of maturation markers on the surface of BMDCs was determined using flow cytometry, while the expression of TLR receptors was determined using RT-PCR. The levels of inflammatory cytokines were measured using iELISA, and the impact on the proliferation of mouse T-lymphocytes was assessed using the MTT method.

Results: The impact of LPS on BMDC maturation, TLRs-mediated cytokine secretion, and antigen presentation was found to be limited. In contrast, rOMP10, rOMP19, and rBP26 were observed to promote BMDC maturation, increase the expression of TLR-2 and TLR-4 mRNA, and activate T-lymphocyte proliferation by significantly increasing the expression of pro-inflammatory cytokines (TNF-α, IFN-γ, IL-6, IL-12) and antigen-presenting molecules. However, rOMP25 and rOMP31 did not promote BMDC maturation, inhibited the expression of MHCI and MHCII antigen-presenting molecules, and increased the expression of inflammation-suppressing cytokines (IL-10 and IL-4), resulting in the inhibition of T-lymphocyte proliferation.

Conclusion: Brucella OMP10, OMP19, and BP26 play an important role in activating the host immune response, while OMP25 together with OMP31 may play a role in Brucella immune escape.

Background: Pulse oximetry is a valuable tool for monitoring animals during anesthesia and assessing the adequacy of administered oxygen therapy.

Aims: To compare the pulse oximeter readings obtained by the Garmin Fenix 5X plus (GF5Xp) smartwatch and transmittance pulse oximetry (TPO) in anesthetized dogs.

Methods: Twelve clinical canine patients requiring anesthesia for castration were prospectively enrolled in this study. The animals were premedicated with intramuscular dexmedetomidine at a dose of 5 µg/kg. Anesthesia was induced through intravenous administration of propofol and maintained using sevoflurane. The arterial hemoglobin oxygen saturation (SpO₂) readings obtained from the tongue using TPO (238 readings) were compared with measurements taken over the lateral side of the tibia using a GF5Xp smart wearable device (238 readings). This comparison was performed using a Bland-Altman plot, where the differences (%) between the methods were plotted against their mean SpO₂ (Gold standard - Device), and the limits of agreement were represented as the mean ± 1.96 times the standard deviation.

Results: The SpO₂ levels in dogs were overestimated by the GF5Xp relative to the readings obtained by the TPO, with the bias of -0.3% (95% CI: -3.1%-2.5%).

Conclusion: GF5Xp may be interchangeable with TPO in dogs. Further studies are required to validate the accuracy of the GF5Xp in non-anesthetized dogs or dogs outside the physiological range.

Background: Staphylococcus aureus is a potential emerging and prevailing multidrug-resistant (MDR) pathogen involved in bovine endometritis.

Aims: Present research evaluated the prevalence and molecular characterization of methicillin-resistant S. aureus (MRSA) and beta-lactam resistant S. aureus (BRSA) and also analyzed the associated risk factors with endometritis along with antibiotic resistance patterns.

Methods: A total of 384 uterine and vaginal fluid samples were collected from the adult dairy cattle and buffaloes showing the clinical signs of endometritis including foul-smelling vaginal discharge, fever, enlarged and thickened uterine horns on rectal palpation, and confirmation by ultrasonography findings. The collected samples were subjected to standard microbiological methods for the detection of S. aureus. The confirmed isolates were further subjected to the Kirby-Bauer disc diffusion test and the detection of the mecA and blaZ genes for the confirmation of MRSA and BRSA.

Results: Study found an overall prevalence of 17.96% for S. aureus from bovine endometritis cases. Among S. aureus isolates, 50.72% and 37.68% isolates were confirmed MRSA while BRSA was found as 36.23% and 18.84%, based on phenotypic and genotypic methods, respectively. Phylogenetic analysis indicated the possibility of pathogen transmission within and between livestock animals. Risk factor analysis showed that the breed of animal, visible discharge from vagina, lactation number, insemination procedure, and calving place showed significant (P<0.05) association with S. aureus-associated endometritis. Antimicrobial susceptibility testing of study isolates showed the resistance to various commonly used antibiotics.

Conclusion: The study concluded that S. aureus is found in 17.96% of bovines affected with endometritis and require further intensive research to elucidate the farm economic losses.

Background: Using medicinal plants in broiler diets has been gaining attention as an alternative to synthetic additives due to their potential health benefits and lower risk of residue accumulation.

Aims: The present study primarily aimed to evaluate and compare the effects of herbal additives, specifically barberry (Berberis vulgaris), sumac (Rhus coriaria, L), symbiotic, and antibiotic on broiler chickens.

Methods: A total of 384 one-day-old broiler chicks (Ross 308) were assigned to eight different dietary treatments, with six replicates per treatment. Experimental diets included control diet (CON), and other experimental groups were supplemented with 0.2 g/kg virginiamycin (VM), symbiotic (SS), 1 g/kg (B₁) and 2 g/kg (B₂) barberry seed powder, 1 g/kg (S₁) and 2 g/kg (S₂) sumac seed powder and 1 g/kg sumac seed powder + 1 g/kg barberry seed powder (B₁ + S₁).

Results: The study results indicated that body weight increased in birds fed with VM and SS-supplemented diets (P<0.05) during 1 to 42 days of age. All dietary treatments except CON increased the count of Lactobacillus spp. and decreased the number of coliforms versus at the end of the experiment (P<0.05). Antibody titers against Gambaro disease were higher in birds fed diets B2 and B1 + S1 (P<0.05). The results also indicated that the heterophil to lymphocyte ratio was significantly lower in the SS and B1 + S1 groups as compared with the control group.

Conclusion: A mix of sumac and barberry (1%) powdered seeds has the potential to improve performance, and disease responsiveness and intestinal microbiota in broiler.

Background: Peste des petits ruminants virus (PPRV) is one of the most economically important pathogens in sheep and goats. Fusion (F) and Hemagglutinin (H) proteins are the main immune-stimulating antigens.

Aims: The present study aimed to clone and express F and H genes in baculovirus, and evaluate the immunogenicity of recombinant proteins produced by sf9 cells in mice.

Methods: Amplified F and H genes (by RT-PCR using specific primers) were cloned into pFastBac Dual plasmid. The recombinant plasmid was transformed in DH10Bac host cells. SDS-PAGE and Western blotting was performed to control the recombinant protein, and a whole pure and specific recombinant protein was obtained.

Results: The immunogenicity of 20 μg of non-adjuvant recombinant proteins in Balb-c mice showed better results compared with the attenuated PPR vaccine.

Conclusion: The recombinant protein obtained from this study can be a suitable candidate for the production of recombinant vaccines against PPRV.