β-defensins: An innate defense for bovine mastitis

Review (Published online: 26-08-2017)

26. β-defensins: An innate defense for bovine mastitis

Ankita Gurao, Sudhir Kumar Kashyap and Ravinder Singh

Veterinary World, 10(8): 990-998

ABSTRACT

Immune challenges are inevitable for livestock that are exposed to a varied range of adverse conditions ranging from environmental to pathogenic stresses. The β-defensins are antimicrobial peptides, belonging to "defensin" family and therefore acts as the first line of defense against the major infections occurring in dairy cattle including intramammary infections. The better resistance to mastitis displayed by Bos indicus is implicit in the fact that they have better adapted and also has more sequence variation with rare allele conserved due to lesser artificial selection pressure than that of Bos taurus. Among the 58 in silico predicted β-defensins, only a few have been studied in the aspect of intramammary infections. The data on polymorphisms occurring in various β-defensin genes is limited in B. indicus, indicating toward higher possibilities for exploring marker for mastitis resistance. The following review shall focus on concisely summarizing the up-to-date research on β-defensins in B. taurus and discuss the possible scope for research in B. indicus.

Keywords: Bos indicus, β-defensins, mastitis.

Incidence of bovine clinical mastitis in Jammu region and antibiogram of isolated pathogens

Research (Published online: 25-08-2017)

25. Incidence of bovine clinical mastitis in Jammu region and antibiogram of isolated pathogens

Adil Majid Bhat, Jasvinder Singh Soodan, Rajiv Singh, Ishfaq Ahmad Dhobi, Tufail Hussain, Mohammad Yousuf Dar and Muheet Mir

Veterinary World, 10(8): 984-989

ABSTRACT

Aim: This study was conducted to evaluate the incidence of clinical mastitis in bovines of Jammu region, to identify the infectious organisms responsible for it, and the antimicrobial sensitivity of isolated pathogens.

Materials and Methods: The study was conducted on cases that were presented to the Medicine Division of Teaching Veterinary Clinical Complex, Faculty of Veterinary Sciences and Animal Husbandry, R.S. Pura, Jammu, Jammu and Kashmir. A total of 260 cases of bovines were presented from June 30, 2012, to July 01, 2013, out of which 30 cases were of clinical mastitis. The diagnosis of clinical mastitis was made on the basis of history and clinical examination of affected animals.

Results: Animal and quarter-wise incidence of clinical mastitis were found to be 11.5% and 5.76%, respectively. Of the 23 isolates obtained, Staphylococcus aureus (60.87%) was the most frequently isolated organism, followed by coagulase negative Staphylococci (13.04%), Streptococcus uberis (4.35%), Streptococcus dysgalactiae (8.69%), and Escherichia coli (13.04%). The antimicrobial sensitivity of isolates revealed maximum sensitivity to enrofloxacin, gentamicin, amoxicillin/ sulbactam, ceftriaxone/tazobactam, ceftizoxime, ampicillin/sulbactam and least sensitivity for oxytetracycline and penicillin.

Conclusion: Staphylococcus spp. is the major causative agent of clinical mastitis in bovines of Jammu region. The causative agents of the clinical mastitis were most sensitive to enrofloxacin and gentamicin.

Keywords: antimicrobial sensitivity, bovines, clinical mastitis, incidence.

Antimicrobial activity of yeasts against some pathogenic bacteria

Research (Published online: 24-08-2017)

24. Antimicrobial activity of yeasts against some pathogenic bacteria

Gamal Younis, Amal Awad, Rehab E. Dawod and Nehal E. Yousef

Veterinary World, 10(8): 979-983

ABSTRACT

Aim: This study was designed to isolate and identify yeast species from milk and meat products, and to test their antimicrobial activity against some bacterial species.

Materials and Methods: A total of 160 milk and meat products samples were collected from random sellers and super markets in New Damietta city, Damietta, Egypt. Samples were subjected to yeast isolation procedures and tested for its antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. In addition, all yeast species isolates were subjected to polymerase chain reaction (PCR) for detection of khs (kievitone hydratase) and pelA (pectate degrading enzyme) genes.

Results: The recovery rate of yeasts from sausage was 20% (2/10) followed by kareish cheese, processed cheese, and butter 10% (1/10) each as well as raw milk 9% (9/100), and fruit yoghurt 30% (6/20). Different yeast species were recovered, namely, Candida kefyr (5 isolates), Saccharomyces cerevisiae (4 isolates), Candida intermedia (3 isolates), Candida tropicalis (2 isolates), Candida lusitaniae (2 isolates), and Candida krusei (1 isolate). khs gene was detected in all S. cerevisiae isolates, however, pelA gene was not detected in all identified yeast species. Antimicrobial activity of recovered yeasts against the selected bacterial species showed high activity with C. intermedia against S. aureus and E. coli, C. kefyr against E. coli, and C. lusitaniae against S. aureus. Moderate activities were obtained with C. tropicalis, C. lusitaniae, and S. cerevisiae against E. coli; meanwhile, all the tested yeasts revealed a very low antimicrobial activity against P. aeruginosa.

Conclusion: The obtained results confirmed that some kinds of yeasts have the ability to produce antimicrobial compounds that could inhibit some pathogenic and spoilage bacteria and these antimicrobial activity of yeasts enables them to be one of the novel agents in controlling spoilage of food.

Keywords: antimicrobial, meat products, milk, pathogenic bacteria, yeasts.

Isolation and characterization of bacteriophages with lytic activity against common bacterial pathogens

Research (Published online: 23-08-2017)

23. Isolation and characterization of bacteriophages with lytic activity against common bacterial pathogens

R. K. Shende, S. D. Hirpurkar, C. Sannat, Nidhi Rawat and Vinay Pandey

Veterinary World, 10(8): 973-978

ABSTRACT

Aim: Present investigation was conducted to isolate and characterize bacteriophages with lytic activity against common bacterial pathogens.

Materials and Methods: A total of 60 samples of animal waste disposal from cattle (42) and buffalo (18) farms were collected from three different strata, i.e., top, mid, and bottom of collection tank. Samples were primarily subjected to rapid detection methods, and then isolation of phage was done by double agar layer method using Bacillus subtilis (BsH) and Escherichia coli (EH) as host system. Phages were characterized on the basis of plaque morphology, temperature, pH susceptibility, and host range.

Results: Recovery of phages was higher from dairy cattle farm waste (78.57%) as compared to buffalo farm waste (72.22%) and bottom layer of tank showed maximum recovery. Bacillus subtilis (91%) supported the growth of more phages as compared to E. coli (9%). Three different phage morphotypes were observed each against Bacillus subtilis (BsHR1, BsHR2, and BsHR3) and E. coli (EHR1, EHR2, and EHR3). Mean phage titer of above six phage isolates ranged between 3x1010 and 5x1012 plaque forming units/ml. Viability of phages was by, and large unaffected at 70°C within 2-3 min, and phage isolates were completely inactivated below pH 3 and above 11. Coliphage EHR1 had widest host range followed by BsHR1 and BsHR2 while EHR2, EHR3, and BsHR3 had low lytic activity.

Conclusion: It could be concluded from the present study that the Bacillus and Coli phage has wide host range and thus exhibits the potential to be used as drug substitute tool against common bacterial pathogens.

Keywords: Bacillus subtilis, bacteriophage, Escherichia coli, host range, sewage.

Molecular etiopathology of naturally occurring reproductive diseases in female goats

Research (Published online: 22-08-2017)

22. Molecular etiopathology of naturally occurring reproductive diseases in female goats

V. Beena, R. V. S. Pawaiya, K. Gururaj, D. D. Singh, A. K. Mishra, N. K. Gangwar, V. K. Gupta, R. Singh, A. K. Sharma, M. Karikalan and Ashok Kumar

Veterinary World, 10(8): 964-972

ABSTRACT

Aim: The aim of the present study was to investigate the molecular etiopathology of occurrence of reproductive diseases in female goats. Reproductive diseases in goats account for major economic losses to goat farmers in terms of valuable loss of offspring and animal productivity.

Materials and Methods: A total of 660 female genitalia were examined for pathological conditions (macroscopic and microscopic lesions). The etiopathological study was carried out for the presence of pathogenic organisms such as Brucella, Chlamydia, and Campylobacter in the uterus and ovary. Based on the microscopic lesions, suspected samples were subjected to diagnostic polymerase chain reaction (PCR) for various etiological agents employing 16srRNA genus specific primers for Campylobacter and Chlamydophila and OMP31 gene-based PCR for Brucella melitensis and nested PCR using ITS-1 gene primers for Toxoplasma gondii. For Brucella suspected samples, immunohistochemistry (IHC) was also performed.

Results: In studied female genitalia, 108 (16.30%) showed gross abnormalities with overall 23.32% occurrence of pathological conditions (macroscopic and microscopic lesions). Pathological involvement of the uterus was the highest 68 (62.96%), followed by the ovaries 27 (25%) and other organs. Major uterine condition observed was endometritis (5.60%). In uterine infections, 35 (5.30%) samples were found positive for Campylobacter spp., 12 (1.81%) samples for B. melitensis, and 3 (0.45%) samples were positive for Chlamydophila spp. Among the samples positive for B. melitensis by PCR, 3 were found positive by IHC also. Corynebacterium ovis was detected by PCR using specific primers in a case of hydrosalpinx. It was concluded that many pathological lesions in female genitalia of functional significance play a major role in infertility in goats.

Conclusion: The present study concluded that many pathological lesions in female genitalia of functional significance play a major role in infertility in goats.

Keywords: Brucella melitensis, Campylobacter spp., Chlamydophila spp., Corynebacterium ovis, etiopathology, female genitalia, goat, ovary, reproductive diseases, uterus.

Subchronic toxicity of Nile tilapia with different exposure routes to Microcystis aeruginosa: Histopathology, liver functions, and oxidative stress biomarkers

Research (Published online: 21-08-2017)

21. Subchronic toxicity of Nile tilapia with different exposure routes to Microcystis aeruginosa: Histopathology, liver functions, and oxidative stress biomarkers

H. M. R. Abdel-Latif and A. M. Abou Khashaba

Veterinary World, 10(8): 955-963

ABSTRACT

Background: Toxic cyanobacterial blooms (Microcystis aeruginosa contains microcystins [MCs]) have been reported to induce clinicopathological alterations as well as different oxidative stress in aquatic biota.

Aim: Three-week subchronic exposure experiment was carried out on Nile tilapia, to determine their effects on fish behavior, tissues, liver functions, antioxidant enzymes, and lipid peroxidation.

Materials and Methods: Fish were exposed to four main treatments; orally fed diet plus toxic cells of M. aeruginosa (containing 3500 μg/g MC-LR), immersion in 500 μg MC-LR/L, intraperitoneal injection of M. aeruginosa MC-LR with a dose of 0.1 ml of extracted toxin at a dose of 200 μg/kg bwt, and the fourth one served as a control group, then the fish were sacrificed at the end of 3rd week of exposure.

Results: The results revealed no recorded mortality with obvious behavioral changes and an enlarged liver with the congested gall bladder. Histopathology demonstrated fragmentation, hyalinization, and necrosis of the subcutaneous musculature marked fatty degeneration, and vacuolation of hepatopancreatic cells with adhesion of the secondary gill lamellae associated with severe leukocytic infiltration. Furthermore, liver functions enzymes (aspartate aminotransferase and alanine aminotransferase, and the activities of glutathione peroxidase, glutathione reductase, lipid peroxidase, and catalase enzymes) were significantly increased in all treatments starting from the 2nd week as compared to the control levels.

Conclusion: In this context, the study addresses the possible toxicological impacts of toxic M. aeruginosa contain MC-LR to Nile tilapia, and the results investigated that MC-LR is toxic to Nile tilapia in different routes of exposure as well as different doses.

Keywords: catalase, lipid peroxidation, Microcystis aeruginosa, microcystins, Nile tilapia.

Beta-lactamase antimicrobial resistance in Klebsiella and Enterobacter species isolated from healthy and diarrheic dogs in Andhra Pradesh, India

Research (Published online: 20-08-2017)

20. Beta-lactamase antimicrobial resistance in Klebsiella and Enterobacter species isolated from healthy and diarrheic dogs in Andhra Pradesh, India

N. Mohammad Sharif, B. Sreedevi, R. K. Chaitanya and D. Sreenivasulu

Veterinary World, 10(8): 950-954

ABSTRACT

Aim: The aim of this study was to characterize beta-lactamase antimicrobial resistance in Klebsiella and Enterobacter species isolated from healthy and diarrheic dogs in Andhra Pradesh.

Materials and Methods: A total of 136 rectal swabs were collected from healthy (92) and diarrheic (44) dogs, bacteriological cultured for Klebsiella and Enterobacter growth and screened for beta-lactamase antimicrobial resistance phenotypically by disc diffusion method and genotypically by polymerase chain reaction targeting blaTEM, blaSHV, blaOXA, blaCTX-M Group 1, 2, blaAmpC, blaACC, and blaMOX genes.

Results: A total of 33 Klebsiella and 29 Enterobacter isolates were recovered. Phenotypic beta-lactamase resistance was detected in 66.6% and 25% of Klebsiella and Enterobacter isolates, respectively, from healthy dogs and 66.6% and 60% of Klebsiella and Enterobacter isolates, respectively, from diarrheic dogs. Overall, incidence of extended-spectrum beta-lactamase (ESBL) phenotype was found to be 21.2% (7/33) in Klebsiella isolates, whereas none of the Enterobacter isolates exhibited ESBL phenotype. Predominant beta-lactamase genes detected in Klebsiella species include blaSHV (84.8%), followed by blaTEM (33.3%), blaCTX-M Group 1 (15.1%), and blaOXA (6.1%) gene. Predominant beta-lactamase genes detected in Enterobacter species include blaSHV (48.2%), followed by blaTEM (24.1%), blaAmpC (13.7%), and blaOXA (10.3%) gene.

Conclusion: The present study highlighted alarming beta-lactamase resistance in Klebsiella and Enterobacter species of canine origin in India with due emphasis as indicators of antimicrobial resistance.

Keywords: beta-lactamase resistance, dogs, Enterobacter, extended-spectrum beta-lactamase, Klebsiella.