azam mokhtari

Given the significant zoonotic threat posed by Salmonella enterica serovar Dublin (S. Dublin) and its substantial impact on animal populations and public health, the objective of the present study was to assess the immunogenicity and protectivity of subcutaneous administration of Salmonella Dublin bacterin in a murine model. 

Specific pathogen-free female BALB/c mice were tested for Salmonella-free status, and housed in controlled conditions. A formalin-killed bacterin was prepared from a local isolate of S. Dublin using a well-established protocol, ensuring bacterial inactivation and safety. Groups 1 through 3 of mice were received, respectively, either phosphate buffered saline plus alum or a single dose of inactivated bacterins with and without alum adjuvant via subcutaneous route. Immune responses were evaluated through microagglutination, enzyme-linked immunosorbent assay, delayed-type hypersensitivity, interferon-gamma assays, and challenge with viable S. Dublin.

Microagglutination and enzyme-linked immunosorbent assay tests revealed alum-adjuvanted injection as the best method for stimulation of anti-S. Dublin antibodies production. The gamma interferon production and delayed hypersensitivity tests, crucial for cellular immunity, were also most elevated in mice injected with alum-adjuvanted S. Dublin bacterin. After the challenge with the live bacteria, the isolation rate of S. Dublin was significantly different (P=0.03) among the different groups but only mice injected with alum-adjuvanted showed a significant difference (P≤0.05) compared to the control group.

This study emphasizes the efficacy of alum as an adjuvant in inactivated S. Dublin vaccines. Insights gained from both humoral and cellular immune responses, provide valuable knowledge for the development of S. Dublin vaccination strategies.

Mastitis is an inflammatory disease of the mammary gland, caused by many infectious agents such as bacteria, fungi, and viruses. Streptococci are reported to be among the major pathogens causing bovine mastitis around the world, which may cause clinical and subclinical forms of mastitis. Mastitis is one of the primary diseases of dairy cows and is responsible for remarkable economic losses due to reduction in quantity and quality of milk, cost of treatment, and the early culling of the cows. Considering the existence of substantial industrial and traditional dairy cattle farms in Chaharmahal and Bakhtiari province and the fact that mastitis is the most common disease in dairy industries, this study aimed to identify the role of streptococci in subclinical mastitis in dairy cows in Chaharmahal and Bakhtiari province. For this purpose,134 subclinical mastitis milk samples were collected from 8 dairy farms in Chaharmahal and Bakhtiari province, based on the california mastitis test (CMT) results and screened for the streptococcal cause of mastitis. DNAs were extracted from collected specimens and PCR was performed with specific primers for Streptococcus agalactiae, Streptococcus uberis, and Streptococcus dysgalactiae. Out of 134 mastitis milk samples 10 (7.5%), 14 (10.4%), and 5 (3.7%) samples were positive for S. agalactiae, S. uberis, and S. dysgalactiae respectively. The result of this research shows that 21.6 (29:134) percent of mastitis in dairy cattle farms in the studied region may be due to streptococci. The obtained data can be used in management and prevention strategies for cattle mastitis control in Chaharmahal and Bakhtiari province.

Contagious ovine digital dermatitis (CODD), a severe lameness-causing bacterial foot disease, significantly impacts the sheep industry's economy and welfare. Treponema species responsible for bovine digital dermatitis (BDD), including Treponema medium, Treponema phagedenis, and Treponema pedis, have been identified in CODD lesions. In this study, Treponema spp. was detected in 42 skin samples from 110 sheep that had footrot lesions (38%). The lesions were more presented on hindlimbs (55.5%). The Kurdish sheep breed exhibited the highest Treponema positivity rate with 47.8% (n = 20), while pure Afshari sheep and Afshari-Kurdish hybrids showed an equal prevalence of 26.2%. The prevalence of lesion scores 4 and 5 in the Treponema-positive group (33.3% and 40.5% respectively) was significantly higher compared to the Treponema-negative group (23.5% and 11.8% respectively) further underscores the potential role of Treponema infection in the progression of severity of the infection. The southern region of the Khorasan Razavi province exhibited a significantly higher prevalence of Treponema-positive cases (88.1%, n = 37) compared to the northern regions (7.1%, n = 3) and Mashhad (4.8%, n = 2). This is the first report of investigation of the possible presence of CODD in Iranian sheep flocks, which should be potentially considered to prevent negative impacts on sheep production, welfare, and antibiotic use (improper antibiotic usage) in the farms.

It has been determined that there is a direct relationship between the severity of mastitis and the virulence factors produced by bacterial agents. Identifying bacterial virulence factors is neccecary for designing suitable vaccines against mastitis. The aim of the present study was molecular diagnosis of selected virulence factors of endemic isolates of S. aureus involved in bovine mastitis. A total of 180 milk samples were collected from cows with clinical (37 samples, 20.6%) and subclinical (143 samples, 79.4%) mastitis from 8 semi-industrial dairy farms of Chaharmahal and Bakhtiari province, Iran. After culture and purification, coagulase, catalase and oxidase tests were performed. DNA was extracted from S. aureus suspected colonies. Final confirmation was performed using PCR test on the specific 23S rRNA gene of the bacteria. Thirty one (17.22%) out of the 180 collected samples were found to be positive for S. aureus by PCR, of which 2 cases were related to clinical mastitis and 29 cases were related to subclinical mastitis. The highest frequency of virulence genes was related to the Coa gene (90.32%), followed by ClfB (87.09%), LukD, and fnbB (80.64%), LukE (77.41%), fnbA (74.19%), Hla (48.38%). The lowest frequency was related to the Hlb gene (45.16%). Based on the obtained results, the diagnosis of the virulence factors of S. aureus has the potential of being used in the development of vaccines for the prevention of mastitis.

Bovine herpesvirus-1 (BHV-1) is the causative agent of a domestic and wild cow disease namely infectious bovine rhinotracheitis (IBR). Severe economic damage due to IBR is possible to occur and vaccines are not completely effective against the disease. Therefore, over the recent years, the development of effective and genetic-based therapies to control viral infections, such as IBR has been remarkable. A common way to evaluate such therapeutic strategies is cloning of the viral target sequence into appropriate vectors for the preparation of cell lines expressing viral subgenomic replicons. Due to the required duties of UL25 gene, serine protease substrate domain of this gene was cloned in pCDH-CMV-MCS-EF1-cGFP-T2A-Puro lentiviral vector at the upstream of GFP gene. The cloning accuracy was verified by restriction of enzyme digestion and sequencing. Thus, this recombinant plasmid will be available to produce lentiviral vectors with the desired gene; after infection of eukaryotic cells with such lentiviral vectors the target gene will be expressed.

Border disease virus (BDV) is a serious pathogen of sheep and goats worldwide. The virus causes considerable economic losses in animal husbandry. Therefore, developing effective and genetic-based therapies to control viral infections, such as BDV, has been remarkable over recent years. A common way to evaluate such therapeutic strategies is by cloning the desired fragment into appropriate vectors to develop cell lines expressing it. Due to the required duties of the NS3 gene for BDV proliferation, this gene's HELICc and nucleotide binding site domain was synthesized and cloned in a lentiviral vector upstream of the GFP gene. The cloning accuracy was verified by digestion with restriction enzymes and sequencing. Thus, the BDV-NS3 HELICc and nucleotide binding site carrying plasmid was prepared successfully and will be applied in a second or third lentiviral packaging system for stable expression of the desired gene.

The aim of this study was to investigate the effects of thyme endophytes belonging to the Lordegan region on Shigella sonnei and Candida albicans.  Thyme components were immersed in 70% ethanol (2 minutes), 3.5% sodium hypochlorite (5 minutes), and 75% ethanol (30 seconds), respectively, and lastly washed with sterile distilled water. Subsequently, they were cultured on YEA and PA medium, and the endophytes were isolated. A total of 8 bacterial endophytes were taken from different parts of the Lordegan thyme plant (stem, leaves, and roots) and examined. The endophytes isolated from thyme were bacilli, coccobacilli, and cocci. Antimicrobial and inhibitory properties of endophytes isolated from Lordegan thyme were studied in two methods structural factors and secretory metabolites of endophytes. The results of this study showed the beneficial effects of thyme endophytes on Shigella sonnei and Candida albicans. Bacterial endophytes isolated from thyme (roots stems and leaves) showed stronger inhibitory effects than the study of secretory metabolites against S. sonnei and C. albicans. In general, thyme could be a good alternative to chemical drugs in the treatment of Candida infections, especially cutaneous mucosal candidiasis, and shigellosis, and can be used in therapeutic cases, food, health, and pharmaceutical industries.

These days, silver nanoparticles (Ag NPs) have been given considerable attention and applied in medical technology due to their great antimicrobial and antioxidant features. In the present study, we aimed to synthesize Ag NPs through the reduction of silver nitrate in the presence of Vitex agnus castus L fruit extract.

After collecting fruits, their extract was prepared and added to Ag NO3 to produce Ag NPs. The effect of different parameters like AgNO3 concentration (0.5, 1, 3, and 5 mM), sunlight exposure, and sunlight irradiation time (10, 20, 30, and 40 min) was investigated in the synthesis of Ag NPs. The features of Ag NPs were characterized using UV‑visible spectroscopy, scanning electron microscope (SEM), X‑ray diffraction (XRD) analysis, and dynamic light scattering analysis. Moreover, antimicrobial function of Ag NPs was evaluated using Escherichia coli and Bacillus cereus bacteria species and minimal inhibitory concentration (MIC) of Ag NPs against these two pathogens was measured.

The results showed that the synthesized nanoparticles had a spherical shape and the range size of 30‑60 nm. For the first time, the antimicrobial activity of synthesized Ag NPs of Vitex agnus castus L fruit extract was shown.

It can be stated that the biosynthesis of Ag NPs using fruit extract of this plant is an environmentally friendly, economic and harmless method without any use of poisonous substances and no side effects. These Ag NPs can be considered as suitable antibacterial agents and replacements for antibiotics.

Bovine digital dermatitis (BDD) is a contagious infectious disease which causes lameness in dairy cows. It has a multifactorial etiology which is not yet fully understood but Treponema spp. seem to play a significant role in development of BDD lesions. This study evaluated the presence of Treponema phylotypes commonly associated with BDD (T. medium/T. vincentii, T. phagedenis and T. putidum/T. denticola), in four farms different areas in Iran. Single biopsies were taken from 113 Holstein cows with active BDD lesions (scored according to size) on the farms and polymerase chain reaction assays used to detect 16S rRNA nucleotide fragments of three BDD Treponema phylotype groups: ‘‘T. medium/T. vincentii’’, ‘‘T. phagedenis’’ and ‘‘T. putidum/T. denticola’’ (now T. pedis). Over 95.00% of samples were positive for at least one of phylotypes, with 89.00%, 91.00 %, and 66.00% of samples were positive for T. putidum/T. denticola, T. phagedenis and T. medium/T. vincentii, respectively. Out of the 113 samples, 60.00% were positive for all three phylotypes, the detection of T. putidum/T. denticola was positively associated with detection of both T. phagedenis and T. medium/T. vincentii. No association between lesion size and phylotypes identified was found but there were significant differences between farms in the proportion of each phylotypes identified. Further research is required to establish the factors influencing the proportions of individual phylotypes, especially at the farm level.

 The endophytes are the fungi or bacteria that live within a plant in a symbiotic relationship. This study aimed to investigate the effect of isolated bacterial endophytes from Allium jesdianum on some bacterial pathogens such as Staphylococcus aureus, Escherichia coli as well as pathogenic fungi, including Trichophyton mentagrophytes and Candida albicans.

Various parts of A. jesdianum including leaves, stems, onions and flowers were randomly collected, cleaned from any contamination and then cultured in a suitable culture medium. The endophyte colonies were purified using chloroform to analyze the anti-pathogenic properties of the structural agents of the bacterial endophyte. To evaluate the anti-pathogenicity of endophyte metabolites, the broth media of the endophyte bacteria was centrifuged and the supernatants were filtered through sterilization. Antibiogram test was performed by disk diffusion method (Kirby Bauer) and the sensitivity was compared. Data were statistically analyzed by t-test and ANOVA.

Eleven bacterial endophytes were obtained from various sections of A. jesdianum.  The endophyte bacterium has an improved antimicrobial effect on T. mentagrophytes. Unlike E. coli, secretory metabolites of endophytic bacteria had an antimicrobial effect on S .aureus and C. albicans.

It can be concluded that the bacterial endophytes of A. jesdianum can be considered to be potential and beneficial agents against human pathogens. A. jesdianum with anti-pathogenic activity could be a source to produce important anti-pathogenic compounds from an agricultural and pharmaceutical point of view.

 Canine distemper (CD) is a highly transmissible serious disease of carnivores. Distemper virus has immunosuppression effects, which, in turn, could lead to opportunistic infections. The present study was performed to detect CDV by the genomic and immunological methods and investigate its co- infection with canine parainfluenza virus type 2 (CPiV-2).

In this study, which was conducted from Spring 2018 to Winter 2019, samples of blood, eye, respiratory, and digestive system were collected from 50 dogs suspected to CDV (group 1: symptomatic dogs) as well as 50 seemingly healthy dogs (group 2: asymptomatic dogs). Rapid distemper immunochromatography kit was applied for the primary detection of CDV. RT_PCR test was also performed using special primers for molecular investigation.

Results of immunochromatography showed twenty nine and one positive cases among dogs suspected to CDV and seemingly healthy dogs, respectively. After RT_PCR assay, in the first group, 37 samples were reported as CDV positive and 11, CpiV-2 positive. Furthermore, three CDV- and one CpiV-2-positive cases were found in the second group. Besides, the frequency of CDV and CpiV-2 co-infection was 4%.

In the present study, using statistical tests, we observed no association between distemper and CpiV-2.

 Canine distemper (CDV) is a highly transmissible serious disease of carnivores. Distemper virus has immunosuppression effects which, in turn, causes opportunistic infections.

 The present study was performed to detect CDV by the genomic and immunological methods and investigate its co-infection with Candida albicans.

 In this study, from spring of 2018 to winter of 2019, blood, eye, respiratory and digestive system samples were collected from 50 CDV suspected dogs and 50 seemingly healthy dogs. Rapid distemper immunochromatography kit was applied for the primary detection of CDV. RT-PCR and PCR tests were performed using special primers for molecular investigation.

 Using immunochromatography, twenty-nine cases and one case had positive results for CDV among dogs suspected of having the disease and seemingly healthy dogs, respectively. After RT-PCR and PCR assays, 37 samples were CDV-positive, and four were C. albicans-positive in the first group. While three CDV and one C. albicans-positive samples were found in the second group. In total, the frequency of co-infection was 4%.

 In the present study, there was an association between distemper and C. albicans using statistical tests. Conducting such studies in an appropriate sample population gives more accurate results.

Foot and mouth disease (FMD) is a severe, highly contagious viral disease of cloven-hoofed ruminants caused by an aphthovirus of the family Picornaviridae. The disease in cattle is clinically characterized by fever and vesicles on the foot, in the oral cavity and on the mammary gland.This study was carried out to determine the changes in some serum biochemical parameters of cattle naturally infected with FMD O in Shahrekord district, Iran. For this purpose, blood samples were obtained from 23 Holsteins with clinical signs of FMD, as well as 22 blood samples from healthy animals. Serum analysis revealed significantly higher levels of AST, CK, CK-MB and LDH activities as well as MDA, troponin I, glucose and triglycerides concentrations in FMD-affected cattle compared to healthy control group (p < 0.05). Serum GPx and SOD activities in cattle with FMD were significantly lower than those in normal animals (p < 0.05), while there was no significant difference in serum CAT activity between 2 groups of animals. It is concluded that oxidative stress and some degrees of myocardial and pancreatic lesions develop in FMD-affected cattle. These findings provided information to better understand the pathogenesis of the disease and gives further insight to improve supportive treatment procedures in FMD virus infection in cattle.

Escherichia coli is an important pathogen and microorganism of the normal intestinal flora of humans and animals. One of the important serotypes of E. coli is O157: H7. Because of the excessive and arbitrary use of antibiotics, multiple drug resistance has increased against these organisms. The main problem in treating infections caused by E. coli is its dependence on the administration of a large number of common antibiotics and the resistance of some strains to antibiotics. Phage therapy refers to the therapeutic use of phages to eliminate bacterial infections. In the first step, it is necessary to separate and identify bacteriophages that affect the target bacteria. Therefore, the present study was performed to isolate the phage that was effective on enterohemorrhagic E. coli isolates.

In this study, after collection of sewage samples, bacteriophages were isolated by filtration and enrichment in an enterohemorrhagic E. coli overnight culture. The presence of bacteriophage was detected by plaque observation in a double layer agar and confirmed by TEM electron microscopy.

The results of the observation with electron microscopy revealed the presence of bacteriophage with the appearance of the Cystoviridae, Myoviridae and Podoviridae families. Unfortunately, although the titration of phages and molecular study were not performed in the current study due to the lack of budget, we found antibacterial activity of isolated phages using plaque formation observation, and the presence of phages belonging to Cystoviridae, Myoviridae and Podoviridae families was confirmed by TEM microscopy. Therefore, the effective phage against O157: H7 was successfully identified, isolated, and purified.

Numerous studies have shown that a variety of animal species can be the hosts of the hepatitis E virus. In addition to pigs, wild boars, deer, and rats, new types of hepatitis E virus have been found in ferrets and bats.

Due to the limited reports of virus identification in deer and the potential role of this animal as a reservoir in maintaining the virus, in the present study, the genome of the virus was investigated in the samples of feces and gastrointestinal swabs of Gazelle.

Samples were collected from 50 Gazelle in the protected area of Moteh and the lands around Maymeh City from winter, 2017 to winter, 2019. After RNA extraction and reverse transcription reaction, the genomic identification of the virus was performed by RT-PCR.

The results of the present study showed that out of 50 samples taken, three samples were positive for the hepatitis E virus, including one sample from female Gazelle under one year of age and two samples from female animals over one year of age.

No statistically significant relationship was found between hepatitis E infection, age, and sex using statistical tests. The present study indicated the contamination of Iranian wildlife animals and the importance of these animals as the potential reservoirs of the disease.

Canine distemper virus (CDV) is an extremely contagious pathogen that causes deadly diseases in carnivores worldwide.

Considering the effect of CDV on the host immune system and the increased risk of other infections, the present study aimed to investigate the incidence of coinfection with CDV and Bordetella bronchiseptica, using genomic and serological methods.

In this study, 50 blood samples, eye samples, respiratory swabs, and gastrointestinal tract swabs were taken from dogs, which showed symptoms of respiratory and gastrointestinal tract involvement, suggesting CDV infection. Also, 50 seemingly healthy dogs were included in this study. The animals were referred to Isfahan clinics between the spring of 2018 and the winter of 2019. For the initial diagnosis of CDV by immunological methods, a rapid CDV immunochromatography kit was used. To investigate for the genomes of both pathogens, after DNA and RNA extraction and reverse transcription of the extracted RNA samples, a PCR assay was performed using specific primers.

Based on the results of the RT-PCR assay, of 50 samples taken from dogs with suspected CDV infection, 37 were positive for the presence of CDV nucleic acids, and 20 were positive for the presence of B. bronchiseptica nucleic acids. Also, of 50 samples taken from seemingly healthy dogs, three were positive for CDV, and 15 were positive for B. bronchiseptica nucleic acids.

In the present study, of 100 samples taken from dogs with suspected CDV infection and apparently healthy dogs, 15 showed coinfection (12 samples from dogs with symptoms of CDV and three from seemingly healthy dogs). However, no significant relationship was found between CDV and B. bronchiseptica infections. It seems that future studies with a larger sample size can provide us with more accurate results.

Staphylococcus aureus (S. aureus) is a major cause of nosocomial infections in humans and animals. Because of the widespread resistance to antibiotics, microbiologists are trying to find other therapeutic interventions such as phage therapy for bacterial infections.

The present study aimed to isolate staphylophages with lytic effects on methicillin-resistant S. aureus (MRSA) clinical isolates as a potential alternative agent to antibiotic therapy.

This experimental, descriptive study is performed in the Microbiology Laboratory of Shahrekord University (Iran) from September 2018 to March 2019. Two cocktails of staphylophages were isolated from Isfahan (Iran) urban sewage samples. The double-layer agar method was used to detect lytic phages. Morphology characteristic by transmission electron microscopy (TEM) images was used to identify staphylophages. One hundred and thirty three S. aureus were isolated from clinical samples of two teaching hospitals in Isfahan and Shiraz, Iran. Methicillin resistance and the presence of the mecA gene were determined by the disk diffusion method and polymerase chain reaction (PCR) assay, respectively. The phage susceptibility of mecA positive isolates was determined by plaque assay.

Two staphylophage cocktails were prepared, which had lytic effects on forty-four MRSA isolates. Cocktails 1 and 2 lysed 19 (14.2%) and 25 (18.7%) isolates, respectively. Of 133 S. aureus isolates, 88.7% carried the mecA gene.

Different bacteriophages in two phage cocktails had relatively good lytic effects on S. aureus clinical isolates. Therefore, phage cocktails may be an appropriate alternative to antibiotics against S. aureus.

 Disinfectants have important clinical applications. Antibiotic resistance of some hospital pathogens such as Pseudomonas aeruginosa has led to the use of disinfectants. In the present study, the effects of four commercial disinfectants; Hydrocare, Benzalkonium Chloride, Cetrimide-C, and Vico sience on Pseudomonas aeruginosa isolates were investigated.

 The dilutions of four tested disinfectants recommended by the manufacturer were prepared and their effects on twelve Pseudomonas aeruginosa isolates were evaluated at five, ten, fifteen minutes after the bacterial inoculation.

 Hydrocare and Benzalkonium Chloride inhibited the growth of all strains while Cetrimide-C disinfectant did not inhibit the growth of bacterial strains at any time. The Vico sience completely inhibited the growth of bacterial strains at ten and fifteen minutes after the addition of disinfectant. Since the recommended dilutions by the manufacturer were prepared and evaluated in the present study, the inefficiency of some of the disinfectants indicated that the evaluation and dilution assay of the disinfectant is necessary prior to routine use in laboratories or health centers.

Contagious ecthyma (CE) is a zoonotic skin disease of small ruminants, caused by an epitheliotropic parapoxvirus and has a worldwide distribution with significant economic importance. The objective of this study was to determine clinicopathlogic abnormalities in goats naturally infected with CE. Thirty two goats, 16 affected with CE and 16 normal healthy goats were used in this study. CE was confirmed by histopathology and PCR. Blood samples were collected from jugular veins for hematological and biochemical analysis. The PCV, WBC and neutrophil counts of CE affected goats were significantly higher than those in the unaffected goats (p < 0.05). Serum biochemical analysis revealed significantly higher levels of BUN, glucose, MDA and iron concentrations as well as CK, AST, GGT and catalase activities in CE affected goats than healthy animals (p < 0.05). The serum activity of catalase, SOD and GPx in goats with CE were significantly lower than those in normal goats. Creatinine concentration in serum of goats with CE was significantly lower than that in heathy ones (p < 0.05). There was no significant difference in serum total protein, albumin, total and direct bilirubin, and cholesterol concentrations between CE affected and healthy goats. The alterations observed in hematological and biochemical parameters of CE affected goats could be related to weight loss, subnutrition, oxidative stress and pathological changes including inflammation and secondary bacterial infection. These findings could be useful for the management of cases of sheep and goats with CE.

Bovine viral diarrhea virus (BVDV) is in the genus Pestivirus of the family Flaviviridae and causes significant economic and hygienic losses in cattle farms throughout the world. The virus has spread worldwide and despite the wide use of various control strategies against it, BVD remains prevalent. In recent years, numerous measures such as anti-viral gene therapies are frequently employed to control BVDV infection. One way to evaluate these measures is the cloning of conserved areas of the viral genome into suitable vectors for the preparation of cell lines expressing sub- genomic replicons of the virus. In this study, after multiplication of conserved sequences of BVDV- NADL NS3 and 5’UTR by RT-PCR, these fragments were cloned in pWPI- linker B lentiviral vector at the upstream of GFP gene. The validity of cloning was confirmed using restriction enzyme digestion and sequencing. Therefore these recombinant plasmids will be available to produce lentiviral transfer vectors carrying the transgenes using the lentiviral packaging systems.

BIV is a well-known bovine immunosuppressive cause, but its pathogenesis has not been well characterized. In recent years, it has been hypothesized that infection with BIV might predispose cattle to be infected by other agents.
This study was performed to investigate of BIV and Brucella co-infection so that in the future more studies will be done on the issue of predisposing cattle to other microorganisms like Brucella after BIV infection.
Blood samples were collected from a total of 2290 cattle in Iran (490 and 1800 cattle in non-industrial and industrial dairy farms, respectively from Isfahan and Chaharmahal and Bakhtiari provinces). The BIV-positive animals were detected by Lab-ELISA and nested PCR tests.
In this study, the overall prevalence of BIV in Iran was 1.61% (4.5% and 0.83% in non-industrial and industrial dairy farms, respectively).
There was a statistically significant relationship between BIV status and Brucella infection using Chi square and Pearson’s correlation coefficient test for all of the samples (p=0.0001, r=0.24), samples from Chaharmahal and Bakhtiari (p=0.044, r=0.13) and from industrial farms in Isfahan (p=0.001, r=0.074).

BIV is a well-known bovine immunosup-pressive cause، but its pathogenesis has not been well characterized. It seems that it is possible that cofactors such as co- infection with other bovine viral pathogens may play a role in enhancing the pathogenesis of BIV infection; BVDV also has immunosuppressive effects. The aim of this study was determination of possible correlation between BIV and BVDV infections. Blood samples were randomly collected from a total of 1800 cattle in dairy industrial farms in Isfahan and Chaharmahal va Bakhtiari provinces of Iran. First BIV or BVDV positive sera were screened by ELISA، and then samples were analyzed to detect BIV proviral DNA or BVDV RNA، using PCR. Out of 1800 blood samples، 19 (1. 06%) samples were BVDV positive، while BIV positive samples were 10 (0. 55%). Nine (0. 5%) samples contained both BIV and BVDV genomes and were positive in ELISA، while one of the samples (0. 05%) was only BIV positive. In this study، there was a statistically significant relationship between BIV status and BVDV infection using Chi square and Pearson''s correlation coefficient test (p=0، r=0. 65).