Iranian journal of veterinary research最新文献

Background: Infectious bursal disease (IBD) caused substantial economic loss in central and western India during 2020 and 2021.

Aims: The study was conducted to characterize IBD virus (IBDV) from field outbreaks.

Methods: The study was conducted on 360 samples from 42 poultry flocks. The samples were subjected to histopathology and molecular detection, followed by phylogenetic typing of the partial VP2 gene.

Results: The mortality ranged from 15.25 to 60.18%. The necropsy showed hemorrhages on thigh muscles, mottled spleen, swelling of kidneys and bursae with hemorrhages, and cheesy exudate. Histopathology revealed extensive necrosis and depletion of follicular lymphoid cells within the cortex and medulla, along with widespread hemorrhages, edema, and cystic cavities in the bursa. The field isolates showed cytopathic effects in the seventh passage. The cytopathic effects included swelling, rounding, granulation of cytoplasm around the nucleus, fragmentation of the infected cells, and detachment. The reverse transcription-polymerase chain reaction amplified 664 bp partial VP2 gene. The phylogenetic analysis identified 19 field isolates as very virulent IBDVs (vvIBDVs) and three as classical strains.

Conclusion: The results indicated that different vvIBDV strains are involved in disease outbreaks in central and western India.

In recent years, the hazardous use of antibiotic growth promotors in the poultry industry has led to the development of drug resistance and violative tissue residues. Therefore, the European Union Regulation banned application of these growth promotors, and the international authorities have searched for other natural and safe feed additive sources as substitutes for antibiotics. Chitosan has been used as a feed-additive alternative in veterinary medicine practices worldwide. Chitosan and chitosan-based nanoparticles have been extensively investigated in the poultry production system and have proved several positive impacts. The overall performance parameters of broilers and layers have been improved following dietary treatments with chitosan. Besides, chitosan showed antimicrobial activity against many bacterial, fungal, viral, and parasitic diseases as well as boosting of the immune response. Modulation of the antioxidant activity and modification of some blood parameters have also been detected owing to dietary chitosan supplementations. Moreover, chitosan nanoparticles have been now applied as a vaccine delivery vehicle and a mucosal adjuvant for many important poultry bacterial and viral diseases. Therefore, this review article sheds light on the effects of chitosan and its nanoparticle forms on the production traits of broilers and layers, their antimicrobial, immuno-regulatory, and antioxidant properties, as well as their effects on the blood constituents and vaccine production.

Background: Precise and on-time diagnosis of the udder's diseases is important, because of their economic importance. Udder structures like teat, parenchyma, and supramammary lymph nodes can be evaluated by ultrasonography.

Aims: The study aimed to evaluate the ultrasonographic technique for imaging the supramammary lymph nodes and udder's tissue in Saanen goats and the relation between the findings of ultrasonography and subclinical mastitis.

Methods: Thirty milking Saanen goats were evaluated in the study. Milk sampling from each teat was performed under standard conditions for bacteriological culture and somatic cell count (SCC). A 7.5 MHz linear transducer was used for the ultrasonography of teats with the water bath technique, and supramammary lymph nodes and udder's tissues were imaged using a 10 MHz linear transducer with direct contact. The length, height, area, and echogenicity of each lymph node and the teat canal wall diameter were measured using ImageJ 1.47v on the ultrasonography scanned images and analyzed by SPSS software.

Results: There was no significant relationship between the dimension of the supramammary lymph nodes and SCC or culture. Age had a positive relationship with lymph node size. No significant relationship was seen between the size of the supramammary lymph node before and after the treatment. Supramammary lymph nodes' echogenicity of the quarter with subclinical mastitis and healthy ones represented no significant difference before and after the treatment.

Conclusion: Ultrasonography of the udder, teat, mammary gland, and supramammary lymph nodes is a safe and non-invasive method for visualizing separate structures. The positive relationship between SCC and milk echogenicity as well as supramammary lymph nodes dimension, and age was described.

Background: The paper describes the first documentary evidence of intestinal histoplasmosis in Indian goats.

Case description: A goat flock in delta region of Tamil Nadu with a report of mortality of eight animals with the history of inappetence, constipation, tenesmus and hematochezia. Three goat carcasses were presented for necropsy.

Findings/treatment and outcome: Postmortem examination showed mesenteric lymphadenomegaly with greyish yellow viscous contents. Ileum contained scattered dark brownish tubular concretions inside the lumen. Colon and caecum had scattered firm serosal and mucosal nodules with caseous exudate. Lumen contained viscous haemorrhagic content. Mucosa of the colon showed numerous tiny ulcers. Urinary bladder serosa showed a focal firm nodule with caseous exudate and irregular firm mass. Microscopically, lung revealed oval inclusions with clear halo in pulmonary macrophages. Caecum and colon showed ulcers with necrotic core. Necrotic border showed multinucleated giant cells and oval bodies with clear halo. Mesenteric lymph node and urinary bladder revealed pyogranulomatous inflammation with aggregation of macrophages filled with numerous tiny inclusions. Periodic acid-Schiff and Grocott's methanamine silver staining techniques and morphological features of the inclusion confirmed it as Histoplasma capsulatum. The case showed a resemblance with human colonic histoplasmosis.

Conclusion: This report documents the first incidence of intestinal histoplasmosis in goats. Interestingly, the intestinal form of histoplasmosis is considered to be common in humans and it showed similarity with human disease in goats based on the gross and microscopic lesions.

Background: Methicillin-resistant Staphylococcus aureus (MRSA), affecting livestock and human beings, has become a global public health hazard with economic consequences.

Aims: The current study was designed to investigate the prevailing MRSA-associated subclinical mastitis and associated risk factors in dairy buffaloes. The study also highlighted the genetic variations and in silico-based proteomic differences among MRSA isolates.

Methods: Out of 516 milk samples, 45.93% (237/516) were found positive for subclinical mastitis, while the prevalence of S. aureus was recorded 56.12%. The methicillin resistance in S. aureus isolates was evaluated by oxacillin disc diffusion test and molecular identification of the mecA gene.

Results: The results revealed a phenotypic and molecular prevalence of MRSA at 45.11% and 18.79%, respectively. The risk factor analysis revealed that among various assumed risk factors, parity, milking hygiene, milker care during milking, milk yield, housing system, and floor type were significantly associated with subclinical mastitis in buffaloes. The sequencing and phylogenetic analysis showed no significant genetic variations among study isolates and depicted a high similarity with isolates from Africa, USA, India, Italy, Turkey, and Iran. The in-silico protein analysis showed that all sequences had the same protein motifs resembling penicillin protein 2a except Buff-13, whose protein structure resembles alpha-catenin-like protein hmp-1.

Conclusion: The current study was the first report of the genotypic characterization and in silico protein analysis of MRSA from dairy buffaloes in Pakistan. The result highlighted the importance of antimicrobial resistance (AMR) and development of control strategies against MRSA infections.

Background: Optimal vitamin D levels for an effective role in immune function and rickets prevention are thought to vary, but have not yet been definitively determined. Reports on reference values of 25-hydroxyvitamin D (25(OH)D) in cats are limited.

Aims: The study provides information about serum 25(OH)D values in cats with different age, gender, breed, diet type, reproductive status, housing condition, and also the relationship between these levels and various hematological and biochemical parameters.

Methods: Clinically healthy cats (88) were included in the study. Physical examination and assessment of hematological and biochemical parameters were performed on cats in order to confirm their health status. Reference value of serum 25(OH)D was assayed by ELISA method and the effects of age (under six months and above six months), gender, breed, diet (only commercial diet, only homemade food, mixture of commercial and homemade food), reproduction status, and housing conditions on serum 25(OH)D was determined.

Results: The median, 2.5% and 97.5% of 25(OH)D in sampled cats were 19.74 ng/ml, 3.12 ng/ml, and 92.1 ng/ml, respectively. Serum 25(OH)D concentration was lower when homemade diet was used compared to commercial and mixed diets as well as in cats under six months of age compared to older cats.

Conclusion: Diet type and age can affect serum 25(OH)D levels in healthy cats while other parameters had no significant effects.

Background: Extragonadal teratoma in the head and neck region is unusual in veterinary medicine. So far, only one case of oropharyngeal teratoma has been reported in a cat.

Case description: In this report, a 5-month-old kitten was brought to the clinic with the complaint of difficulty breathing, food intake, and oropharyngeal mass. In clinical examination, there was a large mass, protruding from the localization included left buccal mucosa, soft palate, and extending into the oropharynx but no cranial extension was observed in CT scans. The mass was completely resected. Macroscopically, the mass measured 4.5 × 6.5 cm² and contained solid and cystic areas associated with soft and hard tissue components.

Findings/treatment and outcome: Histopathology revealed an extragonadal solid-cystic (grade 0) oropharyngeal mature teratoma containing structures from endoderm, mesoderm, and ectoderm. After an 8-month follow-up control period, no signs of recurrence were observed.

Conclusion: The case was deemed worthy of being presented with its clinical, radiological, and pathological findings, and complete resection was curative for mature teratoma.

Abstract.

Background: Infectious bovine respiratory disease complex (BRDC) is one of the world's major livestock problems.

Aims: The study aimed to determine the diagnostic importance of pentraxin-3, endothelin-1, clinical biochemistry, and hematological parameters in infectious BRDC.

Methods: Animals in this study were Simmental breed, 1-7 years old, untreated, and healthy and BRDC cattle (40 cattle with BRDC in the disease group, and 10 healthy cattle in the control group). Clinical findings such as general posture, respiratory rate per minute, rectal temperature, heart rate per minute, and mental posture of the diseased cattle were recorded. Blood samples were taken from the jugular vein only once from all cattle. Complete blood count from blood samples was measured in an automatic complete blood count device, biochemical parameters in an autoanalyzer, and pentraxin-3 and endothelin-1 were measured by ELISA method.

Results: Rectal temperature, respiratory and pulse rates per minute, total leukocyte count, gamma-glutamyl transferase, urea, total bilirubin, lactate dehydrogenase, creatine kinase, pentraxin-3 and endothelin-1 concentrations were found to be statistically higher in BRDC group than those in the control group (P<0.001).

Conclusion: Pentraxin-3 and endothelin-1 levels were statistically significantly higher in the BRDC group compared to the control group. As a result, pentraxin-3 and endothelin-1 were found to be diagnostically important in cattle diagnosed with BRDC.

Background: Species of the Bacillus genus have a long history of use in biotechnology. Some Bacillus strains have recently been identified for food applications and industrial as safe bacteria, which mostly have been recognized as probiotic strains.

Aims: The primary purpose of the current study was to evaluate the probiotic characteristics of Bacillus subtilis strains isolated and identified from the goat milk samples.

Methods: After sampling from 40 goat milk and cultivation, suspected colonies were subjected to biochemical and molecular identification. Then, the confirmed isolate was assessed for in vitro probiotic tests, including hemolysis and lecithinase properties, bile salt, acid, and artificial gastric juice resistance, antioxidant activity, antibiotics susceptibility, enterotoxin genes detection, and attachment capacity to the HT-29 cells.

Results: Among 11 suspected isolates evaluated, only one isolate was identified as B. subtilis. In vitro tests for this strain showed similar results to other probiotic strains. The B. subtilis strain was susceptible to various antibiotics. The enterotoxin genes were not detected based on PCR assay. Concerning its probiotic characteristics assessment, especially tolerance to bile salts and acidic conditions, the Bacillus strain could have the potential to consider as a probiotic.

Conclusion: Goat milk can be recommended as a source of Bacillus isolates. Also, the isolated strain showed high adaptability to the gastrointestinal environment, relatively equal percentages of adhesion properties, and some safety aspects, having the potential to be considered as an appropriate probiotic.