Iranian journal of veterinary research最新文献

Background: Sarcocystis spp. are one of the most common foodborne tissue cyst-forming coccidia with a public health and veterinary concern.

Aims: The existing study aimed to rectify the epidemiological profile of Sarcocystis spp. infection in the cattle carcasses as well as to explore the structure and phylogenetic features of Sarcocystis spp. isolates.

Methods: A total of 292 cattle carcasses were checked for the existence of sarcocysts using light microscopy (LM) via muscle squash (MS) and peptic digestion (PD) analysis from January 2020 to December 2020. Individual sarcocysts from different cattle tissues were selected for morphologic characterization and DNA extraction. Each sarcocyst's 18S rDNA gene was amplified, sequenced, and analyzed.

Results: Overall, 92.5% (270/292) of cattle tissue samples contained microscopic thin walled sarcocysts and were exclusively found in esophagus by light microscopy. A statistically insignificant relationship exists between the prevalence of infection and age groups, gender of cattle, and the seasonal dynamics (P>0.05). Sarcocysts ultrastructural features were completely discussed. Sequencing of 18S rDNA Sarcocystis gene confirmed S. cruzi (identity 99-100%), which was the first molecular identification of the current isolate in the study region.

Conclusion: The current survey initially provides a brief account of knowledge about the epidemiology of Sarcocystis spp. infecting cattle and it is considered a starting point for the development of health awareness and efficient preventive schemes for this zoonotic protozoan parasite.

Background: Infected poultry is one of the most important reservoirs of Salmonella.

Aims: The investigation presented here was conducted to examine the occurrence of Salmonella in fecal samples among selected flocks of backyard poultry in Bosnia and Herzegovina (B&H).

Methods: Isolation and identification of Salmonella was performed in accordance with BAS EN ISO 6579/AMD 1:2007. When genus Salmonella was confirmed, the determination of the antigenic formula of Salmonella isolates was performed in accordance with BAS CEN ISO/TR 6579-3:2015. After that, Salmonella serotypes were subjected to antibiotic susceptibility testing using EUVSEC sensititre microtiter plates impregnated with different concentrations of antibiotics. At the end, real-time PCR was used to detect extended spectrum β-lactamases (ESBL) and carbapeneamase encoding genes (bla _TEM, bla _SHV, bla _CTX-M, bla _CMY, bla _KPC, bla _NDM, bla _OXA-48, bla _VIM and bla _GES).

Results: Salmonella spp. was detected in pooled feces from four backyards, housed by chickens only. Three isolates were confirmed by slide agglutination as serotype Enteritidis and one as serotype Typhimurium. Antibiotic susceptibility testing by microdilution did not reveal phenotypical resistance among these four isolates. Real-time PCR used to detect ESBL and carbapeneamase encoding genes revealed the bla _TEM gene in one S. Enteritidis isolate.

Conclusion: Data presented in this study provide further evidence on the circulation of different Salmonella serotypes in backyard poultry in B&H. These findings emphasize the potential role of backyard poultry in the epidemiology of salmonellosis and the risks it poses for keepers, consumers, and general public health.

Background: Listeriosis is a zoonotic disease of humans, animals, birds, fish, and crustaceans worldwide. Domestic animals, especially ruminants, are more susceptible to listeriosis. This infectious disease is caused by Listeria monocytogenes, an intracellular bacterium that can cross blood-brain, placental and intestinal barriers. In Pakistan, the incidence and reliable diagnostic tools for the L. monocytogenes are unidentified in Nili-Ravi buffaloes.

Aims: This study was designed to inspect listeriosis in buffaloes through molecular techniques and haemato-biochemical analyses.

Methods: A total of 230 samples (115 milk and 115 faecal samples) were collected from symptomatic listeriosis cases in Nili-Ravi buffaloes of 3 geographical districts (Rawalpindi, Faisalabad, and Muzaffargarh) Punjab, Pakistan. These samples were processed for DNA extraction using commercialized kits, and L. monocytogenes was confirmed by conventional PCR.

Results: The results revealed that 6.08% and 4.34% of the isolates from milk and faecal samples were found positive for L. monocytogenes, respectively. The phylogenetic analysis of these isolates showed 97-100% similarity to isolates from the USA, Switzerland, Japan, and India. The accession numbers on NCBI GenBank appeared as HF558398 (Switzerland), KP965732 (India), EU372032 (USA), and LC259850 (Japan). Haemato-biochemical examinations showed that the values of WBCs, plasma fibrinogen, ALT, and AST significantly increased (P<0.05) in diseased buffaloes compared to healthy ones.

Conclusion: The occurrence of listeriosis in buffaloes urges continuous monitoring and surveillance to prevent this emerging disease in Pakistan.

Background: Information on the prevalence of infectious agents in dairy farms forms the basis for formulating a suitable control strategy; especially in endemic situations.

Aims: A cross-sectional study was undertaken to determine the prevalence of six economically important bovine diseases, causing reproductive disorders including bovine abortion in organized dairy herds in India.

Methods: A total of 1,075 animals (cattle and buffaloes) from 09 dairy farms were screened by ELISA tests.

Results: Bovine viral diarrhoea (BVD) was the most prevalent (56.5%) disease followed by infectious bovine rhinotracheitis (IBR) (45.4%). Prevalence of Q-fever (5.4%) and neosporosis (6.1%) were less on the farms. Although 16.3% of the samples turned positive for brucellosis, the contribution of calf-hood vaccination (B. abortus S19 vaccine) to the prevalence of antibodies cannot be ruled out. The overall prevalence of bovine anaplasmosis, known to cause sporadic abortions in dairy herds, was 34.1% in the 9 farms with a prevalence of less than 20% in 5 farms. Infection of multiple abortifacient (seroprevalence to more than two pathogens) was recorded in 56.8% of animals. A very strong association was observed between BVD and brucellosis (Odds ratio 14.2; P<0.001). Further, a positive association was also seen between seroprevalence of IBR and anaplasmosis, and neosporosis and Q fever (P<0.05).

Conclusion: Viral diseases were found to be more common in the dairy herds than bacterial and protozoan diseases. Increased susceptibility of IBR seropositive cows to other bacterial and viral infections was observed.

Background: Ornithobacterium rhinotracheale (ORT) is one of the most important pathogenic bacteria which cause significant economic losses in poultry breeder countries every year. Aims: The present study was conducted to isolate and investigate the ORT isolates' biochemical, antibiotic resistance, and genotypic characteristics of in industrial poultry flocks with respiratory signs in northern Iran.

Methods: After sampling from 60 different flocks and cultivation of the samples on a selective medium, suspected colonies were subjected to biochemical and molecular identification of ORT. Then, confirmed isolates were aimed to antibiotic resistance assay, hemagglutination test, detection of pOR1 plasmid, and DNA fingerprinting to survey the variability of the isolates.

Results: A total of 13 isolates, including seven isolates from broiler flocks (19.44%) and six isolates from broiler breeder flocks (25%) were obtained. Almost all isolates showed similar results in terms of basically important biochemical tests. The most resistance rates among all ORT isolates were obtained for ampicillin, erythromycin, ceftriaxone, and penicillin (100%). The majority of ORT isolates were susceptible to furazolidone. The pOR1 plasmid was detected in only two isolates, and analysis of the DNA fingerprinting phylogenetic tree showed four specific genotypic clusters.

Conclusion: According to the results, the isolates showed different antibiotic resistance profiles, and most of the strains proved multiresistant. This can indicate the circulation of various multi-drug resistant strains among poultry farms in northern Iran. Isolates from broilers and broiler breeders were grouped into different clusters by genotyping.

Background: Using unauthorized tissues in sausage is a common food adulteration in some parts of the world.

Aims: This study was designed to compare the accuracy of histochemical and immunohistochemical techniques for the detection of lung tissue in cooked sausage samples.

Methods: Samples with different levels of sheep lung tissues (1, 2.5, and 5%) and a control group were prepared and stained histochemically using H&E, Masson trichrome, and Periodic Acid-Schiff (PAS) stainings, and immunohistochemically using two different commercially-available antibodies of TTF1 Pan-cytokeratin.

Results: The highest positive results of lung tissue detection were achieved in sausage samples stained with anti-TTF1 immunohistochemical staining method. Both anti-TTF1 and anti-pan-cytokeratin immunohistochemical techniques detected all contaminated sausage samples treated with 50 g/kg lung tissues. Anti-TTF1 staining method had the highest odds ratio (7.4), followed by anti-pan-cytokeratin method (6.0). Reversely, PAS staining method had the lowest odds ratio (0.21), followed by Masson trichrome method (1.7). Additionally, anti-TTF1 method had the highest (1.8-31.0) confidence intervale (95%), while PAS had the lowest (0.02-2.1). Totally, the odds ratio of lung tissue detected by immunohistochemical methods were higher than those detected by histochemical staining.

Conclusion: This is the first report on the comparison of histochemical and immunohistochemical techniques for lung tissue detection in cooked sausage. Anti-TTF1 immunohistochemical staining proved to be the most useful technique for the detection of unauthorized lung tissue in cooked sausages.

Background: Difficult calving (dystocia) in buffalo cows is a major obstetrical problem which further leads to metritis complex, encompassing the retention of fetal membranes (RFM), puerperal metritis, endometritis and pyometra with impaired future fertility.

Aims: The current study aimed to evaluate the effect of the administration of intrauterine proteolytic enzymes on the expulsion of fetal membranes and postpartum fertility in dystociac buffaloes.

Methods: Proteolytic enzymes consisting of Trypsin (16 mg), Chymotrypsin (16 mg), and Papain (8 mg) were dissolved in 500 ml normal saline were administered after 1 h of assisted delivery in dystociac buffaloes along with the conventional therapy.

Results: The treated animals (n=15) expelled fetal membranes within a shorter period of time (P=0.043) compared to the control group (n=15) with none in the treatment group retaining it for more than 24 hours. Fewer (26.67 vs 73.33%; P=0.027) postpartum uterine infections developed in the treated animals compared to the control group. The interval between first postpartum estrus (P=0.067), service period (P=0.554), and open days (P=0.557) was shorter in the treatment group compared to the control group where postpartum anestrus developed less frequently (26.67 vs 66.67%; P=0.066) in the animals treated with enzymatic therapy. Systemic illness (neutrophillia) was reduced in the treatment group compared to the control on day 20 (64.55 ± 1.14% vs 70.23 ± 0.99%; P=0.001) and 45 (55.05 ± 1.63% vs 64.92 ± 1.45%; P<0.001) postpartum.

Conclusion: It is concluded that proteolytic enzymes therapy after assisted delivery in dystociac buffalo cows could help in the early expulsion of fetal membranes and reduce uterine infections with decreased neutrophils count.

Background: Salmonellosis is one of the most important zoonotic diseases in humans and animals worldwide.

Aims: The main objective of this study was to report serovars, clonal relatedness, and antimicrobial resistance of Salmonella strains isolated from human, different animal hosts including pigeons, broilers, cattle, camel, parrots, and hamsters in different regions of Iran.

Methods: Twenty-four Salmonella isolates were confirmed at the genus level by biochemical tests and polymerase chain reaction (PCR) by showing the presence of invA gene. Serovars were determined and their clonal relatedness was assessed by RAPD-PCR and antibiotic resistance profiles.

Results: Overall, Salmonella Typhimurium was the most prevalent serovar (45.8%, 11/24), which was recovered from humans, pigeons, and camels. Salmonella Enteritidis (29.2%, 7/24) was the second common serovar that was recovered from cattle, broilers, humans, and hamsters. Salmonella Infantis (12.5%, 3/24) belonged only to broiler sources, and Salmonella Seftenberg (12.5%, 3/24) was isolated from eggs and a parrot. The major RAPD pattern was VI (33.3%) in which the two S. Typhimurium isolates (belonged to humans and pigeons) exhibited similarity in both RAPD pattern and resistance profile. Antimicrobial susceptibility test showed full resistance to tylosin and erythromycin (100%, 24/24). All isolates (100%, 24/24) were susceptible to ceftriaxone, cefixime, and gentamicin. In total, 75% of the isolates were multi-drug resistant (MDR) and revealed 15 different antimicrobial resistance profiles (R-type).

Conclusion: This study supports the potential transmission of Salmonella serovars via animal contacts. Thus, it is necessary to establish a national systematic monitoring program with one health approach for controlling Salmonella infections.

Background: Staphylococcal mastitis is a major cause of concern to the dairy industry in India and several countries worldwide. Though Staphylococcus aureus is the major cause, coagulase negative staphylococcal species (CoNS) are being increasingly reported in recent years.

Aims: To investigate the incidence of coagulase negative staphylococcal species in bovine mastitis.

Methods: Isolation of staphylococci was carried out from 237 milk samples of cows and She buffaloes with clinical and subclinical mastitis from different regions of Andhra Pradesh and Karnataka. CoNS isolates were identified by tube coagulase test using fresh rabbit plasma and coagulase gene PCR. We employed the biochemical test scheme published elsewhere previously for identification of the CoNS isolates up to species and subspecies levels. Seven representative isolates were identified by 16S rDNA sequencing to check the accuracy of biochemical test based identification.

Results: The CoNS constitute the majority of the staphylococcal isolates from mastitis (80/125, 64%) in this region. Using biochemical test scheme, the CoNS isolates from bovine mastitis were identified as S. cohnii sub sp. cohnii, S. simulans, S. capitis sub sp. capitis, S. cohnii sub sp. xylosus, and S. lugdunensis. The CoNS species S. schleiferi, S. haemolyticus, S. sciuri, S. xylosus, S. chromogenes, and Macrococcus epidermidis were identified by 16S rDNA sequencing.

Conclusion: The 16S rDNA sequencing is the appropriate method for the identification of CoNS species. This study highlighted coagulase negative staphylococcal species as possible etiological agents of mastitis.

Background: Zearalenone (ZEA), which is one of the most prevalent wheat and corn seeds mycotoxins causes acute and chronic toxicities in ruminants, poultry, and aquatic animals. Among commercial toxin binders, only a few active charcoals have the significant ability to adsorb ZEA contamination; nevertheless, active charcoal is not considered a sound additive by the feed industry.

Aims: This study aimed to screen and identify the ZEA-degradation compounds of the Zataria multiflora (Shirazi thyme) in the cattle rumen fluid.

Methods: In this investigation, essential oil and different extracts (n-hexane, ethyl acetate, and methanol) of the aerial part of Shirazi thyme (at three concentrations of 0.5, 1, and 2 mg/ml) were screened to reduce ZEA contamination conditions (2 µg/ml) in rumen fluid. ZEA-content was analyzed by high-performance liquid chromatography (HPLC) with a fluorescence detector. In addition, Shirazi thyme phytochemical compounds responsible for eliminating ZEA were localized by HPLC-based activity profiling and then identified by mass spectrometry (LC-MS).

Results: Both n-hexane and methanol extracts of Z. multiflora, considerably remediated ZEA (63-78%) from rumen fluid. According to HPLC-based activity profiling of Z. multiflora extract and LC-MS analysis, two triterpene compounds, including ursolic and oleanolic acids were introduced as ZEA degradation agents.

Conclusion: Z. multiflora could be recommended as a new botanical source, and ursolic and oleanolic acids could be introduced as new phytochemical compounds that degrade ZEA.