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Volume 17 | January
Research Article | 04 Jan 2024
Screening of Streptococcus suis in swine workers of selected states in Peninsular Malaysia
Chee Yien Lee, Zunita Zakaria, Gayathri Thevi Selvarajah, Farina Mustaffa-Kamal, Kenny Gah Leong Voon, Michelle Wai Cheng Fong, and Peck Toung Ooi

Volume-17 | Issue-1 | Article-1 | https://doi.org/10.14202/vetworld.2024.1-7

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Streptococcus suis is a zoonotic pathogen that is highly associated with contact between live pigs and raw pig material. In view of the recent reports of human infections in Malaysia, epidemiological data on the status of S. suis in the human population, especially among people working closely with pigs and/or raw pork, should be provided. The aim of this study was to detect S. suis among individuals working in the swine industry in several major pig production areas in Peninsular Malaysia. Demographic information, exposure determinants, and oral swabs were collected from swine personnel, including farmers, butchers, and veterinarians. Oral swabs were subjected to bacterial isolation and conventional polymerase chain reaction (PCR) assays for S. suis detection. The study included 40 participants working in the swine industry, with a predominant representation of males (62.5%) and Malaysian Chinese individuals (60.0%) who consumed pork (92.5%). Notably, none of the participants reported consuming raw or partially cooked pork. In spite of their occupational exposure risk, none of the oral swabs showed positive results for S. suis infection. To the best of our knowledge, this is the first report and detection study of S. suis using oral swabs obtained from swine personnel in Peninsular Malaysia. Keywords: carrier, high-risk occupation, human, Streptococcus suis.
Research Article | 04 Jan 2024
Prevalence and zoonotic risk factors of Mycobacterium bovis tuberculosis in cattle at the cattle-wildlife-human interface in South and East Cameroon
Armelle Prudence Kouengoua Kouengoua, Yves Ledoux Tsissa, Nestor Denakpo Noudeke, Roland Nankam Chimi, Arouna Njayou, Abdou Karim Issaka Youssao, Mahamadou Dahouda, Cyrille Boko, Victorien Dougnon, Julius Awah-Ndukum, and Farougou Souaibou

Volume-17 | Issue-1 | Article-2 | https://doi.org/10.14202/vetworld.2024.8-16

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Bovine tuberculosis (bTB) is a contagious and notifiable disease, which is prevalent in cattle populations of many countries and in several wildlife species worldwide. However, the role of wildlife in the transmission and/or maintenance of bTB at the human-wild animal-animal interface and the epidemiology of zoonotic disease are poorly understood in Cameroon, where many wildlife species exist. This study aimed to estimate the prevalence and zoonotic risk factors of bTB at the cattle-wildlife-human interface in the South and East regions of Cameroon. We conducted a descriptive cross-sectional study from May to October 2022 in the southern region (Vallée du Ntem and Dja et Lobo) and eastern region (Haut Nyong and Lom et Djérem) of Cameroon to determine risk factors for bTB in Zebu Bororo, Goudali, Ndama, and Simmental cattle breeds. A comparative intradermal tuberculin testing (CIDT) was performed on 160 cattle randomly selected from herds using the threshold recommended by the World Organization for Animal Health. An interviewee-administered questionnaire was used to gather epidemiological data on sociodemographics, interaction between cattle and wildlife, and awareness of zoonotic tuberculosis (TB) from 90 cattle professionals. The prevalence of bTB at the herd level and associated risk factors were estimated using multiple logistic regression models. Based on the comparative intradermal tuberculin test (CIDT), the estimated prevalence of bTB in 160 cattle (Zebu Bororo, Goudali, Ndama, and Simmental) in South and East Cameroon was 6.8% (4.35%-9.41%) and 1.8% (0%-3.6%) for threshold values 3 mm and 4 mm, respectively. The prevalence obtained by simple intradermal tuberculin test (IDT) was 0.6% (0%-1.2%) for a threshold value 4 mm. Univariate analysis revealed three risk factors associated with bTB with significant odds ratios (OR; p = 0.05): herd size (OR = 4.88; 95% confidence interval [CI]: 1.24-32.56); cattle aged>10 years (OR = 0.17; 95% CI: 0.05-0.53); and victims of bTB organ seizure (OR = 0.015; 95% CI: 0.002-0.067). Multivariate analysis showed that being a cattle herder and contact between wildlife and livestock due to forage was significantly associated with bTB exposure (adjusted OR = 0.02; p = 0.001). Bovine TB is prevalent in cattle of the South and East Cameroon. Comparative IDT of cattle reared in the epidemiological and environmental context of the study areas yielded better results at a threshold of 3 mm than at a threshold of 4 mm recommended by the World Health Organization. Factors associated with exposure to/appearance of bTB were high herd size, cattle aged >10 years old, seizures of tuberculous organs, shepherding as a profession, and contact between cattle and wildlife can be due to lack of forage. Keywords: bovine tuberculosis prevalence, East and South Cameroon, livestock-wildlife-human interface, zoonotic risk factors.
Research Article | 04 Jan 2024
Association of heat-shock protein 70.1 gene with physiological and physical performance of Bali cattle
Ikhsan Suhendro, Ronny Rachman Noor, Jakaria Jakaria, Rudy Priyanto, Wasmen Manalu, and Göran Andersson

Volume-17 | Issue-1 | Article-3 | https://doi.org/10.14202/vetworld.2024.17-25

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Global warming challenges cattle productivity and welfare since it affects heat stress and scarce feed. The heat-shock protein 70 (HSP70) gene is essential in cytoprotection against stressors, protecting cells from dysregulated gene expression and apoptosis. This study aimed to identify significant genetic markers of the HSP70.1 gene that can be leveraged genetically to enhance thermotolerance and production in Bali cattle further. Animals were sampled from three different rearing systems. In this study, 83 healthy adult male Bali cattle without abnormalities were utilized. Single-nucleotide polymorphism (SNP) diversity associated with the physiological and physical traits of Bali cattle was assessed using SNPStat online software. Gene expression for putative SNPs and their genotypic groups was further evaluated. There were 15 polymorphic SNPs (c.-185G>A, c.-69T>G, c.10G>C, c.19A>G, c.45C>T, c.101INS, c.115T>C, c.130T>C, c.136G>T, c.159G>C, c.164G>T, c.234G>A, c.303G>A, c.333C>A, and c.456C>T) identified, of which 12 were associated with the assessed trait. Nine SNPs were associated with physiological traits, while eight were with physical traits. The c.136G>T as a novel, high minor allele frequency, and associative SNP was selected for HSP70 gene expression. Individuals with the TT genotype have a trim physique, susceptible physiology, and high HSP70 mRNA expression. On the other hand, the GG genotype was significantly associated with larger physique, lower physiology, and low HSP70 mRNA expression. The higher expression may indicate that HSP70.1 is involved in mitigating the deleterious effects of stress. As a result, the animal experienced negative energy balance, decreasing body size. Single-nucleotide polymorphism c.136G>T is a candidate biomarker for heat resistance traits in Bali cattle. Keywords: Bali cattle, gene expression, heat stress, HSP70, polymorphism, single-nucleotide polymorphism.
Research Article | 04 Jan 2024
A systematic review and meta-analysis of the global prevalence and relationships among Burkholderia pseudomallei sequence types isolated from humans, animals, and the environment
Sa-ngob Laklaeng, Doan Hoang Phu, Jirarat Songsri, Sueptrakool Wisessombat, Wanida Mala, Wilaiwan Senghoi, Preeda Phothaworn, Manit Nuinoon, Tuempong Wongtawan, and Wiyada Kwanhian Klangbud

Volume-17 | Issue-1 | Article-4 | https://doi.org/10.14202/vetworld.2024.26-36

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Burkholderia pseudomallei, a highly pathogenic bacterium responsible for melioidosis, exhibits ecological ubiquity and thrives within soil and water reservoirs, posing significant infection risks to humans and animals through direct contact. The aim of this study was to elucidate the genetic diversity and prevalence patterns of B. pseudomallei sequence types (STs) across a global spectrum and to understand the relationships between strains isolated from different sources. We performed a systematic review and meta-analysis in this study. Extensive research was carried out across three comprehensive databases, including PubMed, Scopus, and ScienceDirect with data collected from 1924 to 2023. A total of 40 carefully selected articles contributed 2737 B. pseudomallei isolates attributed to 729 distinct STs and were incorporated into the systematic review. Among these, ST46 emerged as the most prominent, featuring in 35% of the articles and demonstrating a dominant prevalence, particularly within Southeast Asia. Moreover, ST51 consistently appeared across human, animal, and environmental studies. Subsequently, we performed a meta-analysis, focusing on nine specific STs: ST46, ST51, ST54, ST70, ST84, ST109, ST289, ST325, and ST376. Surprisingly, no statistically significant differences in their pooled prevalence proportions were observed across these compartments for ST46, ST70, ST289, ST325, and ST376 (all p > 0.69). Conversely, the remaining STs, including ST51, ST54, ST84, and ST109, displayed notable variations in their prevalence among the three domains (all p < 0.04). Notably, the pooled prevalence of ST51 in animals and environmental samples surpassed that found in human isolates (p < 0.01). To the best of our knowledge, this study is the first systematic review and meta-analysis to investigate the intricate relationships between STs and their sources and contributes significantly to our understanding of B. pseudomallei diversity within the One Health framework. Keywords: Burkholderia pseudomallei, melioidosis, meta-analysis, One Health, sequence type, systematic review.
Research Article | 04 Jan 2024
Genetic structure and diversity of green turtle (Chelonia mydas) in the Gulf of Thailand
Poommate Chomchat, Worata Klinsawat, Kaitkanoke Sirinarumitr, Natnaree Inthong, and Theerapol Sirinarumitr

Volume-17 | Issue-1 | Article-5 | https://doi.org/10.14202/vetworld.2024.37-49

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The International Union for the Conservation of Nature and Natural Resources lists the green turtle as endangered. Green turtle nesting behavior in the Gulf of Thailand has decreased to <50% of the 1995 level. The population structure of green turtles in the Gulf of Thailand has not yet been studied. This study aimed to characterize the genetic diversity of green turtles in the Gulf of Thailand based on comparisons of mitochondrial DNA (mtDNA) control region with sequences of Indo-Pacific management units (MUs) and rookeries, to investigate population structures, and to explore phylogeographic relationships. Blood samples (1 mL each) from 91 stranded green turtles were collected from four parts of the Gulf of Thailand (eastern, upper, central, and lower). The control mtDNA region was amplified by polymerase chain reaction using LCM15382 and H950 primer. The obtained 384-bp or 770-bp sequences were analyzed for haplotype, clade, and haplotype and nucleotide diversities and were used to construct a phylogenetic tree and haplotype network diagram, respectively. In addition, we analyzed genetic differentiation within and among populations of green turtles in the Gulf of Thailand and between green turtles in the Gulf of Thailand and other Indo- Pacific MUs and rookeries. In total, 12 (based on 384 bp) or 13 (based on 770 bp) haplotypes and two clades (clades VII and VIII) were identified, with nine or 10 haplotypes belonging to clade VIII and three haplotypes belonging to clade VII. Of the new haplotypes, four or five were identified and classified as clade VII (two haplotypes, for both fragment lengths) and clade VIII (two or three haplotypes, for 384 bp or 770 bp fragments, respectively). The overall haplotype and nucleotide diversity of green turtles in the Gulf of Thailand were high (0.755 ± 0.039 and 0.01146 ± 0.00248, respectively). Based on the analysis of molecular variance, green turtles in the Gulf of Thailand could be divided into two subpopulations (UC-Eastern Gulf of Thailand [UC-EGT] and lower Gulf of Thailand [LGT]). Comparisons with other MUs and rookeries in the Indo-Pacific showed that UC-EGT was not genetically different from the Peninsular Malaysia and Eastern Taiwan (Lanyu) MUs and the Terrangganu and Mersing rookeries, and LGT were not genetically different from Peninsular Malaysia, Sipadan, Brunei Bay, Eastern Taiwan (Lanyu), Scott Reef and Browse Island, and Gulf of Carpentaria MUs and the Perak, Perhentain Island, Redang, Pahang, and Vietnam rookeries. To the best of our knowledge, this is the first report to identify the haplotypes and clades of green turtles in the Gulf of Thailand and to show that the populations in the Gulf of Thailand not only present high genetic diversity but also have haplotypic endemism. Longer mtDNA fragments (770 bp) increased the resolution of the stock structure. Clade VII is a unique clade not only for Japan but also for Thailand and Malaysia, and CmP82 is a unique haplotype for both the Gulf of Thailand and Malaysia. Conservation and management of these populations are important to preserve the genetic diversity, biological diversity, and evolutionary potential of green turtles in the Gulf of Thailand. Keywords: genetic diversity, green turtle, Gulf of Thailand, phylogeographic.
Research Article | 08 Jan 2024
Effect of supersaturated dissolved oxygen on growth-, survival-, and immune-related gene expression of Pacific white shrimp (Litopenaeus vannamei)
Songwut Patkaew, Sataporn Direkbusarakom, Ikuo Hirono, Suwit Wuthisuthimethavee, Sorawit Powtongsook, and Chettupon Pooljun

Volume-17 | Issue-1 | Article-6 | https://doi.org/10.14202/vetworld.2024.50-58

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Oxygen concentration is an essential water quality parameter for aquaculture systems. Recently, supersaturated dissolved oxygen (DO) has been widely used in aquaculture systems to prevent oxygen depletion; however, the long-term effects of supersaturated oxygen exposure on aquatic animals have not been studied. In this study, we examined the effects of supersaturated DO on the growth, survival, and gene expression of Pacific white shrimp (Litopenaeus vannamei). Specific pathogen-free shrimp with a body weight of 8.22 ± 0.03 g were randomly assigned to two groups with four replicates at a density of 15 shrimps per tank. Shrimp were cultivated in recirculating tanks containing 50 L of 15 ppt seawater in each replicate. Oxygen was supplied at 5 mg/L to the control tanks using an air microbubble generator and at 15 mg/L to the treatment tanks using a pure oxygen microbubble generator. Shrimp were fed commercial feed pellets containing 39% protein at 4% of their body weight per day for 30 days. Average daily growth (ADG) and feed conversion ratio (FCR) were determined on days 15 and 30. Shrimp molting was measured every day. Individual hemolymph samples were obtained and analyzed for total hemocyte count, differential hemocyte count, and expression of growth- and immune-related genes at the end of the experiment. Long-term exposure to supersaturated DO significantly affected shrimp growth. After 30 days of supersaturated DO treatment, the final weight and ADG were 14.73 ± 0.16 g and 0.22 ± 0.04, respectively. Shrimp treated with normal aeration showed significantly lower weight (12.13 ± 0.13 g) and ADG (0.13 ± 0.00) compared with the control group. FCR was 1.55 ± 0.04 in the treatment group and 2.51 ± 0.09 in the control group. Notably, the shrimp molting count was 1.55- fold higher in the supersaturated DO treatment than in the supersaturated DO treatment. The expression of growth-related genes, such as alpha-amylase, cathepsin L, and chitotriosidase, was 1.40-, 1.48-, and 1.35-fold higher, respectively, after supersaturated DO treatment. Moreover, the treatment increased the expression of anti-lipopolysaccharide factor, crustin, penaeidin3, and heat shock protein 70 genes by 1.23-, 2.07-, 4.20-, and 679.04-fold, respectively, compared to the controls. Supersaturated DO increased growth and ADG production and decreased FCR. Furthermore, enhanced immune-related gene expression by supersaturated DO may improve shrimp health and reduce disease risk during cultivation. Keywords: gene expression, growth performance, molting, pacific white shrimp, supersaturated dissolved oxygen.
Research Article | 08 Jan 2024
Quality of pork after electron-beam irradiation: A meta-analysis study
Teguh Wahyono, Tri Ujilestari, Mohammad Miftakhus Sholikin, Muhlisin Muhlisin, Muhammad Cahyadi, Slamet Diah Volkandari, and Endy Triyannanto

Volume-17 | Issue-1 | Article-7 | https://doi.org/10.14202/vetworld.2024.59-71

Preview Abstract
Irradiation has become a preferred method for pork preservation in recent years. Electron-beam irradiation is notably recognized for its feasibility and safety among various irradiation methods. This meta-analysis study aims to elucidate the impact of electron-beam irradiation on oxidation parameters, color, sensory attributes, and microbiological conditions in pork. A total of 79 data from 22 articles were aggregated into an extensive database. The irradiation dose ranged from 0 to 20 kGy in this current meta-analysis. The observed parameters encompassed oxidation, color, sensory attributes, and microbiological conditions. A mixed-model approach was used to perform the meta-data analysis, in which irradiation dose was treated as fixed effects and distinct studies (articles) as random effects. Electron-beam irradiation resulted in an increase in thiobarbituric acid-reactive substances levels and peroxide-oxygen value of pork (p < 0.01). Conversely, total volatile-base-nitrogen values (p < 0.05) were observed. Following irradiation, the pH value, lightness (L*), redness (a*), and yellowness (b*) remained unaffected. Pork color tended to decrease after irradiation treatment (p = 0.095 and p = 0.079, respectively) at 7 and 14 days of storage. The irradiation process resulted in an increase in the values of texture and juiciness parameters (p < 0.05). However, electron-beam irradiation resulted in decreased overall acceptability (p = 0.089). In terms of microbiological status, electron-beam irradiation led to a reduction in the populations of Salmonella (p < 0.01), Escherichia coli (p < 0.01), Listeria monocytogenes (p < 0.05), and coliforms (p < 0.05) at 7 and 14 days of storage. Electron-beam irradiation enhances lipid peroxidation in porcine meat. The color of the meat remained unchanged after treatment. However, with regard to sensory properties, electron-beam irradiation showed a tendency to decreased overall acceptability. Most microbiological parameters decreased following electron-beam irradiation. Keywords: electron beam, irradiation, meat, meta-analysis, pork.
Research Article | 08 Jan 2024
Detection of feline immunodeficiency virus by neutral red-based loop-mediated isothermal amplification assay
Wichayet Saejung, Kotchaporn Khumtong, Witsanu Rapichai, Siriluk Ratanabunyong, Amonpun Rattanasrisomporn, Kiattawee Choowongkomon, Oumaporn Rungsuriyawiboon, and Jatuporn Rattanasrisomporn

Volume-17 | Issue-1 | Article-8 | https://doi.org/10.14202/vetworld.2024.72-81

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Feline immunodeficiency virus (FIV) is a retroviral pathogen globally responsible for immunodeficiency disease in cats. However, the current diagnosis based on antibody detection has limitations and can also produce false-positive results. This study aimed to develop a one-pot loop-mediated isothermal amplification (LAMP) process integrated with neutral red (NR-LAMP) assay for detection of FIV proviral DNA. We developed a one-pot, gag gene-based NR-LAMP for convenient, rapid, specific, and sensitive colorimetric inspection of FIV proviral DNA. The developed NR-LAMP was capable of amplifying at an optimum temperature of 65°C for 40 min. No cross-amplification was detected between FIV and other feline viruses tested, indicating the high specificity (98.44%) of the novel FIV-LAMP primer. Our NR-LAMP assay has a detection limit of 4.2 × 101 copies/μL. A total of 80 clinical samples with a background of FIV infection were collected and tested using the proposed method. The NR-LAMP assay showed a high sensitivity of 100% compared to conventional polymerase chain reaction assay. These results support the suitability of NR-LAMP as a potential future alternative clinical molecular approach for further use in the diagnosis of FIV-infected cats. Keywords: feline immunodeficiency virus, loop-mediated isothermal amplification, molecular diagnosis, neutral red.
Research Article | 08 Jan 2024
Adverse neurobehavioral changes with reduced blood and brain cholinesterase activities in mice treated with statins
Rawnaq Faris Al-Shalchi and Fouad Kasim Mohammad

Volume-17 | Issue-1 | Article-9 | https://doi.org/10.14202/vetworld.2024.82-88

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Pleiotropic effects of hypolipidemic statins with behavioral outcomes have been suggested in humans and laboratory animals. There is limited information on the neurobehavioral effects of statins in mice. The aim of the present study was to examine changes in neurobehavioral performance and cholinesterase (ChE) activity in mice after high doses of three commonly used statins (atorvastatin, simvastatin, and rosuvastatin). Two hours after vehicle (control) or statin dosing at 250, 500, 750, or 1000 mg/kg orally, each mouse was subjected to 5 min open-field activity, negative geotaxis at an angle of 45°/60 s, 5 min head pocking, and forced swimming endurance. Plasma, erythrocyte, and brain ChE activities were determined spectrophotometrically 2 and 24 h after oral dosing of statins at 500 and 1000 mg/kg. The statins variably, but dose-dependently and significantly (p < 0.05) delayed the latency to move in the open-field arena, decreased locomotion and rearing, reduced head pocking, and delayed negative geotaxis performance. However, statins significantly increased the duration of forced swimming and decreased the duration of immobility in the swimming tank. Statins significantly and dose-dependently decreased plasma, erythrocyte, and brain ChE activity 2 and 24 h after dosing. Plasma and brain ChE activities recovered by 5%–32.9% and 5.7%–14.4% 24 h later from the 2 h ChE values, respectively. High doses of statins differentially modulate neurobehavioral outcomes in mice in association with reduced plasma, erythrocyte, and brain ChE activity. Plasma or erythrocyte ChE may be used for biomonitoring of the adverse/ therapeutic effects of statins. Keywords: atorvastatin, head pocking, negative geotaxis, open-field activity, rosuvastatin, simvastatin, swimming endurance.
Research Article | 08 Jan 2024
Seroconversion, genotyping, and potential mosquito vector identification of Japanese encephalitis virus in pig sentinel settings in Bali, Indonesia
I Made Kardena, Anak Agung Ayu Mirah Adi, I Nyoman Mantik Astawa, Ida Bagus Made Oka, Shafi Sahibzada, Mieghan Bruce, and Mark O’Dea

Volume-17 | Issue-1 | Article-10 | https://doi.org/10.14202/vetworld.2024.89-98

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Despite the endemicity of Japanese encephalitis virus (JEV) in humans and animals in the Province of Bali, Indonesia, there is little data on whether seroconversion to the virus occurs in pigs, JEV genotypes circulating, and it’s potential mosquito vectors in the area. The aims of this study were to (i) Determine whether JEV infection in Balinese pigs occurs before reaching their sexual maturity, (ii) identify the genotypes of circulating JEV, and (iii) identify potential JEV mosquito vectors at the study sites in urban and peri-urban areas of Bali. Sixteen 1-week-old Landrace piglets from two different sows were housed in Denpasar. Similarly, 18 one-week-old mixed-breed piglets of two different sows were housed in Badung Regency. The piglets were bled every 1 to 4 weeks for up to 24 weeks. Serum samples from the 11 piglets were tested for antibodies against JEV, and seroconversion-suspected sera were titrated using an enzyme-linked immunosorbent assay. Blood of seroconverted sera from pigs were tested using polymerase chain reaction (PCR) to detect the genetic sequence of JEV. The mosquitoes in the sentinels were trapped throughout the study period to identify the potential mosquito vectors of JEV. Antibodies were detected in most of the selected piglets’ sera from weeks 1 to 24 of their age. However, sera of pig B9 collected from the sentinel setting in Badung Regency showed a four-fold increase in antibody titer from week 4 to week 8, indicating seroconversion. PCR testing of blood from B9 (pooled blood sample collected from week 5 to week 8) identified JEV nucleic acids, which were phylogenetically classified as belonging to the JEV genotype III. Meanwhile, 1271 of two genera of mosquitoes, Anopheles spp. and Culex spp. were trapped in the pig sentinels. JEV seroconversion likely occurs before the pig reaches sexual maturity in Badung Regency. Sequence data indicate that JEV genotype III is circulating in the pig sentinel setting in the regency; however, circulating genotypes need to be clarified through increased surveillance. Meanwhile, Culex spp. and most likely Culex quinquefasciatus and Anopheles spp. were the dominant mosquitoes present in the study sites set in the urban area of Denpasar and peri-urban areas of Badung, Bali, indicating that these are likely vectors in spread of JEV in the region. Keywords: genotyping, Japanese encephalitis virus, pig sentinel setting, potential mosquito vectors, seroconversion.
Research Article | 08 Jan 2024
Formalin-fixed stool improves the performance of the Kato–Katz method
Ampas Wisetmora, Atchara Artchayasawat, Porntip Laummaunwai, Opal Pitaksakulrat, Oranard Wattanawong, and Thidarut Boonmars

Volume-17 | Issue-1 | Article-11 | https://doi.org/10.14202/vetworld.2024.99-107

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Parasitic infections are a public health problem worldwide, including in Thailand. An epidemiological survey for helminthiasis based on stool examination uses the Kato–Katz method as recommended by the World Health Organization. Limitations of this method include the need for fresh stool, time requirement, and lack of quality control. The aim of this study was to enhance the efficiency of the Kato–Katz technique using formalin and glycerol solutions and to implement specimen preparation in fieldwork. For the Kato–Katz method, stool samples were divided into formalin-fixed and unfixed groups at various time points and processes. Fresh echinostome eggs were added to each stool group. Incubation with glycerol increased the clearing process. Each group was observed and photographed using a light microscope. Parasite eggs were imaged and compared using the standard Kato–Katz method. Visualization of echinostome eggs from formalin-fixed stool slides was significantly better than that from unfixed stool slides (p < 0.01). Stool samples fixed for 7 days retained normal echinostome eggs morphology. Incubation with glycerol for 1 h resulted in increased Kato–Katz performance by digesting the stool content and enhancing egg observation. Moreover, the results of the Kato–Katz method using fixed and fixed stool plus glycerol for natural helminth infection showed good quality of Opisthorchis viverrini and Taenia egg visualization and normal morphology with a clear background of slides. Formalin-fixed stool could be more suitable than fresh stool for the Kato–Katz method. Keywords: formalin-fixed stool, glycerol, Kato–Katz method, parasitology examination, specimen preparation.
Research Article | 18 Jan 2024
Medical prospects of cryptosporidiosis in vivo control using biofabricated nanoparticles loaded with Cinnamomum camphora extracts by Ulva fasciata
Nesreen Allam Tantawy Allam, Ragaa Abd El-Fatah Hamouda, Doaa Sedky, Mahinour Ezzeldin Abdelsalam, Mona Ebrahim Hussien Abd El-Gawad, Noha Mahmoud Fahmy Hassan, Dina Aboelsoued, Amal M. Abou Elmaaty, Muhammad A. Ibrahim, Hanan Anwar Aly Taie, Ashraf Samir Hakim, Hassan Mohamed Desouky, Kadria Nasr Abdel Megeed, and Marwa Salah Abdel-Hamid

Volume-17 | Issue-1 | Article-12 | https://doi.org/10.14202/vetworld.2024.108-124

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Global efforts are continuing to develop preparations against cryptosporidiosis. This study aimed to investigate the efficacy of biosynthesized Ulva fasciata loading Cinnamomum camphora oil extract on new zinc oxide nanoparticles (ZnONPs shorten to ZnNPs) and silver nanoparticles (AgNPs) as alternative treatments for Cryptosporidium parvum experimental infection in rats. Oil extract was characterized by gas chromatography-mass spectrometry, loaded by U. fasciata on ionic-based ZnO and NPs, and then characterized by transmission electron microscopy, scanning electron microscopy, and X-ray diffraction. Biosafety and toxicity were investigated by skin tests. A total of 105 C. parvum oocysts/rat were used (n = 81, 2–3 W, 80–120 g, 9 male rats/group). Oocysts shedding was counted for 21 d. Doses of each preparation in addition to reference drug were administered daily for 7 d, starting on post-infection (PI) day (3). Nitazoxanide (100 mg) was used as the reference drug. After 3 weeks, the rats were sacrificed for postmortem examination and histopathological examination. Two blood samples/rat/group were collected on the 21st day. Ethylenediaminetetraacetic acid blood samples were also used for analysis of biochemistry, hematology, immunology, micronucleus prevalence, and chromosomal abnormalities. C. camphora leaves yielded 28.5 ± 0.3 g/kg oil and 20 phycocompounds were identified. Spherical and rod-shaped particles were detected at 10.47–30.98 nm and 18.83–38.39 nm, respectively. ZnNPs showed the earliest anti-cryptosporidiosis effect during 7–17 d PI. Other hematological, biochemical, immunological, histological, and genotoxicity parameters were significantly fruitful; hence, normalized pathological changes induced by infestation were observed in the NPs treatments groups against the infestation-free and Nitazoxanide treated group. C. camphora, U. fasciata, ZnNPs, and AgNPs have refluxed the pathological effects of infection as well as positively improved host physiological condition by its anticryptosporidial immunostimulant regenerative effects with sufficient ecofriendly properties to be proposed as an alternative to traditional drugs, especially in individuals with medical reactions against chemical commercial drugs. Keywords: blood biomarkers, Cinnamomum camphora, Cryptosporidium parvum, cytokines, Egypt, genotoxicity, green nanoparticles, rats, Ulva fasciata.
Research Article | 18 Jan 2024
The first record of ostrich feather louse (Struthiolipeurus struthionis) collected from farmed ostriches (Struthio camelus) in the United Arab Emirates
Nighat Perveen, Sabir Bin Muzaffar, Mohammad Nafi Solaiman Al-Sabi, Layaly Hamdan, Adnan Aldarwich, Daniil Iliashevich, Khaja Mohteshamuddin, Olivier Andre Sparagano, and Arve Lee Willingham

Volume-17 | Issue-1 | Article-13 | https://doi.org/10.14202/vetworld.2024.125-130

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Ostrich (Struthio camelus) farming in the United Arab Emirates (UAE) is a relatively new field of farming. Farmed ostriches are susceptible to ectoparasite infestation, which affects their production. This study was conducted to estimate the prevalence of ectoparasites on ostriches raised on a farm in Abu Dhabi Emirate. The feathers of 42 ostriches (26 females and 16 males) were collected and morphologically examined for ectoparasites. In total, 283 lice (89 males and 194 females) were collected from birds. However, there were no ticks or other ectoparasites. Lice were preserved in 1.5 mL tubes containing 70% ethanol and were later identified using taxonomic keys. The prevalence, mean intensity of infection, and mean abundance were estimated. One louse species, Struthiolipeurus struthionis was identified. To the best of our knowledge, this is the first report of S. struthionis in ostriches raised in the UAE with an overall prevalence of 88%. The prevalence of lice was significantly higher in July (100%) than that in May (66.7%). Likewise, the mean intensity and abundance of lice were significantly higher in June (10.6 and 9.94, respectively) than in May (3.25 and 2.2, respectively). The high prevalence of lice poses a serious risk to ostrich farming by negatively affecting the health and productivity of ostriches. Keywords: lice, ostrich parasites, prevalence, Struthiolipeurus struthionis, United Arab Emirates.
Research Article | 18 Jan 2024
Development of antibodies against recombinant staphylococcal enterotoxin B from food poisoning cases
Hidayatun Nisa Purwanasari, Siti Isrina Oktavia Salasia, Fatkhanuddin Aziz, Madarina Wasissa, Fajar Budi Lestari, and Christin Marganingsih Santosa

Volume-17 | Issue-1 | Article-14 | https://doi.org/10.14202/vetworld.2024.131-135

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Staphylococcal enterotoxin B (SEB) is the most common serotype involved in food poisoning. The aim of this study was to develop immunoassay detection methods using a recombinant enterotoxin B antigen protein to produce recombinant polyclonal antibodies in vivo. Staphylococcus aureus isolated from a food poisoning case (strain JH5800) was analyzed by polymerase chain reaction (PCR) and confirmed to contain a seb gene of 477 bp. A SEB segment was amplified, cloned, sequenced, and aligned. The PCR product corresponding to the predicted mature SEB peptide was inserted into Escherichia coli BL21 (DE-3) expression vector and expressed as a hexahistidine-SEB fusion protein. Antiserum against recombinant SEB protein was produced by immunization of Balb/c mice. In the indirect enzyme-linked immunosorbent assay (ELISA), the polyclonal antibodies produced had a titer of 1:3200. The seb gene of Staphylococcus aureus isolated from a poisoning case (JH5800) had a molecular size of about 477 bp and a band of recombinant SEB toxin was observed at approximately 30 kDa on SDS-PAGE gel. The polyclonal anti-SEB antibody titer, as revealed by indirect ELISA, was 1:3200 at 59 days. SEB recombinant protein could be used to produce polyclonal antibodies. ELISA and Western blotting were used to analyze the specificity and sensitivity of the recombinant polyclonal antibodies. Polyclonal antibodies produced could be used to detect SEB on a large-scale. Keywords: antibody, enzyme-linked immunosorbent assay, recombinant, staphylococcal enterotoxin B, Staphylococcus aureus.

Volume-17 | Issue-1 | Article-15 | https://doi.org/10.14202/vetworld.2024.136-142

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Campylobacter jejuni is a major contributor to bacterial enteritis, a common health problem. The resistance of this microaerophilic bacterium to oxidative stress allows it to thrive under aerobic conditions. This study aimed to investigate whether the capacity of C. jejuni to form biofilms in the presence of oxidative stress contributes to the pathogen’s ability to thrive in agricultural settings as well as in chicken slaughter lines. Twenty identified strains originating from chicken samples (eight from caeca contents and 12 from frozen chicken carcasses) were previously isolated and identified according to standard bacteriological protocols, followed by confirmation at the species level using multiplex polymerase chain reaction assay. Crystal violet staining was used to evaluate biofilm formation by these bacteria. Two exposure periods to gaseous ozone (1 and 2 min) were used to assess resistance to oxidative damage. Most of the strong biofilm-forming Campylobacter strains came from imported frozen chicken meat (25%), whereas only 10% came from caeca content. After exposure to gaseous ozone at 600 mg/h for 2 min, strong biofilm-producing strains exhibited a higher survival rate with a limited reduction of up to 3 logs, whereas negative biofilm-producing strains exhibited a limited survival rate with a reduction of 6 logs. Based on our findings, we hypothesized that the presence of C. jejuni strains capable of forming biofilms in poultry farms and/or chicken production facilities triggers a public health alarm as this bacterium seems to be able to adapt more easily to live and thrive in hostile environmental conditions. Keywords: biofilm, Campylobacter jejuni, hostile environment, oxidative stress, poultry meat.
Research Article | 20 Jan 2024
Enzyme characterization of lactic acid bacteria isolated from duck excreta
Dini Dwi Ludfiani, Widya Asmara, and Forita Dyah Arianti

Volume-17 | Issue-1 | Article-16 | https://doi.org/10.14202/vetworld.2024.143-149

Preview Abstract
The production of lignocellulosic biomass waste in the agricultural sector of Indonesia is quite high annually. Utilization of lignocellulosic biomass waste through fermentation technology can be used as feed and biofuel. Fermentation technology requires the involvement of micro-organisms such as bacteria (lactic acid bacteria or LAB). LABs can be isolated from various sources, such as duck excreta. However, there have not been many reports of LAB from duck excreta. The present study aimed to characterize LAB enzymes isolated from duck excreta and obtain LAB enzymes with superior fermentation properties. A total of 11 LAB cultures obtained from duck excreta in Yogyakarta, Indonesia, were tested. Enzyme characterization of each LAB was performed using the API ZYM kit (BioMérieux, Marcy-I’Etoile, France). The bacterial cell suspension was dropped onto the API ZYMTM cupule using a pipette and incubated for 4 h at 37°C. After incubation, ZYM A and ZYM B were dripped onto the API ZYM cupule, and color changes were observed for approximately 10 s under a strong light source. Esterase activity was moderate for all LABs. The activity of α-chymotrypsin, β-glucuronidase, α-fucosidase, and α-mannosidase was not observed in a total of 10 LAB. The phosphohydrolase and amino peptidase enzyme activity of seven LABs was strong. Only six LAB samples showed protease activity. The glycosyl hydrolase (GH) activity was observed in a total of 8 LAB, while the activity of 2 LAB was strong (Lactococcus lactis subsp. lactis K5 and Lactobacillus brevis M4A). A total of 2 LABs have superior properties. L. lactis subsp. lactis K5 and L. brevis M4A have a high potential to be used in fermentation. They have the potential for further research, such as their effectiveness in fermentation, lignocellulose hydrolysis, feed additives, molecular characterization to detect specific enzymes, and their specific activities. Keywords: API ZYM, duck, enzyme, excreta, lactic acid bacteria.
Research Article | 20 Jan 2024
New occurrence of Cirolana capricornica (Isopoda: Cirolanidae) from Epinephelus chlorostigma in Suez Governorate, Egypt
Mohamad Abdulmohsen, Heba I. Abdel-Mawla, Maather M. El-Lamie, Marwa S. Kamel, Sherief M. Abdel-Raheem, Waleed Rizk El-Ghareeb, Ahmed. M. A. Meligy, and Eman M. Abouelhassan

Volume-17 | Issue-1 | Article-17 | https://doi.org/10.14202/vetworld.2024.150-155

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The isopods of the Crustacea are noteworthy. All marine, fresh, and brackish waterways at all depths are home to aquatic organisms. This order also includes species that live on land. This study aimed to report a new occurrence of the isopod Cirolana capricornica on the operculum, mouth, and body cavities of Epinephilus chlorostigma in the Suez Governorate, Egypt. With the help of fishermen, 50 live E. chlorostigma (Linnaeus, 1758) were randomly gathered along the Red Sea coast of the Suez Governorate during November and December 2019 for the current investigation. Isopods were isolated from the fish samples and captured using light and electron microscopy for morphological identification. Some fish were emaciated, and minute white isopods were attached externally to the skin near the gills and mouth cavity, and internally to the mouth cavity. No correlation was observed between body cavity attachment and gross lesions. The prevalence of infestation was 16%. C. capricornica was identified using optical and electron microscopy to analyze the isopod specimens’ morphology. This scavenging isopod species is newly discovered in Egypt. Keywords: Cirolanidae, clinical picture, Crustacea, Isopoda, prevalence.
Review Article | 20 Jan 2024
Rhynchophorus ferrugineus larvae: A novel source for combating broad-spectrum bacterial and fungal infections
Nurdjannah Jane Niode, Billy Johnson Kepel, Sofia Safitri Hessel, Tara Sefanya Kairupan, and Trina Ekawati Tallei

Volume-17 | Issue-1 | Article-18 | https://doi.org/10.14202/vetworld.2024.156-170

Preview Abstract
Antimicrobial resistance is a growing concern due to the growth of antibiotic-resistant microorganisms, which makes it difficult to treat infection. Due to its broad-spectrum antimicrobial properties against a diverse array of bacteria, both Gram-positive and Gram-negative bacteria, and fungi, Rhynchophorus ferrugineus larval antimicrobial peptides (AMPs) have demonstrated potential as antimicrobial agents for the treatment of microbial infections and prevention of antibiotic resistance. This study emphasizes the unexplored mechanisms of action of R. ferrugineus larvae against microorganisms. Among the most widely discussed mechanisms is the effect of AMPs in larvae in response to a threat or infection. Modulation of immune-related genes in the intestine and phagocytic capacity of its hemocytes may also affect the antimicrobial activity of R. ferrugineus larvae, with an increase in phenoloxidase activity possibly correlated with microbial clearance and survival rates of larvae. The safety and toxicity of R. ferrugineus larvae extracts, as well as their long-term efficacy, are also addressed in this paper. The implications of future research are explored in this paper, and it is certain that R. ferrugineus larvae have the potential to be developed as a broad-spectrum antimicrobial agent with proper investigation.
Research Article | 20 Jan 2024
In silico simulation of hyperoside, isoquercetin, quercetin, and quercitrin as potential antivirals against the pNP868R protein of African swine fever virus
Putri Pandarangga, Yohanes T. R. M. R. Simarmata, Adi Berci Handayani Liu, and Dwi Ari Fitri Haryati

Volume-17 | Issue-1 | Article-19 | https://doi.org/10.14202/vetworld.2024.171-178

Preview Abstract
African swine fever (ASF) causes disease in pigs with up to 100% mortality rates. There is no effective vaccine to protect against it. This study aimed to perform in silico docking of ASF virus (ASFV) pNP868R protein with potential flavonoid ligands to identify ligands that interfere with mRNA cap formation. The ASFV pNP868R protein was tested with hyperoside, isoquercetin, quercetin, and quercitrin in this in silico simulation. ASFV pNP868R protein was extracted from the Research Collaboration for Structural Bioinformatics P rotein Data Bank (RCSB PDB) database with PDB ID 7D8U (https://www.rcsb.org/structure/7D8U). Standard ligands were separated from proteins using UCSF Chimera 1.13. The standard ligand was redocked to protein using AutoDockTools 1.5.6 with the AutoDock4 method for validation. In the docking process, the grid box size was 40 × 40 × 40 Å3 with x, y, and z coordinates of 16.433, −43.826, and −9.496, respectively. The molecular docking process of the proposed ligand–protein complex can proceed if the standard ligand position is not significantly different from its original position in the viral protein’s pocket. The root mean square deviation (RMSD), root mean square fluctuation (RMSF), and radius of gyration (RoG) of the hyperoside with the lowest energy binding need to be analyzed with molecular dynamics using Groningen machine for chemical simulation 5.1.1. Molecular docking and dynamic simulation revealed that hyperoside had the most stable and compact binding to the pNP868R protein. Hyperoside binds to the protein at the minimum energy of −9.07 KJ/mol. The RMSD, RMSF, and RoG values of 0.281 nm, 0.2 nm, and 2.175 nm, respectively, indicate the stability and compactness of this binding. Hyperoside is the most likely antiviral candidate to bind to the pNP868R protein in silico. Therefore, it is necessary to test whether this flavonoid can inhibit mRNA capping in vitro and elicit the host immune response against uncapped viral mRNA. Keywords: hyperoside, isoquercetin, molecular docking, pNP868R, quercetin, quercitrin.
Research Article | 22 Jan 2024
Prevalence of multidrug-resistant and extended-spectrum β-lactamase producing Escherichia coli from local and broiler chickens at Cibinong market, West Java, Indonesia
Syaiful Rizal, Intan Nurhapsari, Ima Fauziah, Masrukhin Masrukhin, and Yoga Dwi Jatmiko

Volume-17 | Issue-1 | Article-20 | https://doi.org/10.14202/vetworld.2024.179-184

Preview Abstract
Antimicrobial resistance (AMR) is becoming a public health concern. Foodborne pathogens are infectious agents that can be transmitted from animals to humans through food and can become resistant due to misuse and overuse of antibiotics, especially in poultry. This study aimed to detect the prevalence of multidrug-resistant and extended-spectrum β-lactamase (ESBL)-producing Escherichia coli isolated from local and broiler chickens at the Cibinong market, West Java, Indonesia. A total of 60 cloacal swab samples from 30 local and broiler chickens sold at the Cibinong market in West Java were obtained by random sampling. From these samples, 39 E. coli isolates were obtained after being cultured on eosin methylene blue agar and molecularly identified using polymerase chain reaction (PCR). Six antibiotic disks were used for the antibiotic sensitivity test against E. coli isolates cultured on Mueller-Hinton agar. PCR was performed to detect ESBL genes (blaTEM, blaSHV, and blaCTX-M). A total of 76.47% (39/51) cloacal swab samples were positive for E. coli. All E. coli isolates were sensitive to imipenem (100%), and 38 isolates were sensitive to cefoxitin (FOX) (97.4%). On average, the isolates were sensitive to amoxicillin-clavulanic acid (AMC) (69.2%) and ceftriaxone (CRO) (89.7%). E. coli isolates were occasionally resistant to enrofloxacin (25.64%), followed by gentamicin (20.51%), CRO (10.25%), AMC (7.69%), and FOX (2.56%). The prevalence of E. coli AMR was 10.25% (4/39). All four multidrug-resistant E. coli isolates (blaTEM and blaCTX-M) were confirmed to have the ESBL gene based on PCR. The prevalence of multidrug-resistant and ESBL-producing E. coli is still found, proving that there is still inappropriate use of antibiotics and a need for strict supervision of their use, especially around Cibinong market, West Java. Keywords: antibiotic, chicken, extended-spectrum beta-lactamase, Escherichia coli, multidrug resistance.
Reviewer Acknowledgments | 22 Jan 2024
Veterinary World reviewer acknowledgment 2023
A. V. Sherasiya and Riyaz

Volume-17 | Issue-1 | Article-21 | https://doi.org/10.14202/vetworld.2024.185-188

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Veterinary World editorial team would sincerely like to thank all of our reviewers who contributed to peer review for the journal in 2023.
Research Article | 22 Jan 2024
The combined effect of ultrafine particles of cobalt and manganese oxides and Origanum vulgare herb extract on ruminal digestion in vitro
Aina Maratovna Kamirova, Elena Anatolyevna Sizova, Daniil Evgenievich Shoshin, and Anastasia Pavlovna Ivanishcheva

Volume-17 | Issue-1 | Article-22 | https://doi.org/10.14202/vetworld.2024.189-196

Preview Abstract
At present, detailed studies are being conducted to confirm the safety of the use of metal-containing ultrafine particles (UFP) in animal feeding, preventing the possibility of negative effects on productive qualities and physiological state, as well as on the environment and final consumer, that is, humans. Thus, the purpose of this research was to study the safety of cobalt- and manganese-containing UFP (UFP Co3O4, Mn2O3 UFP) together with Origanum vulgare (PB) herb extract in a bioluminescence inhibition test, as well as the effect of this composition on ruminal digestion in vitro. The safety of the studied samples was determined using a multifunctional microplate analyzer TECAN Infinite F200 (Tecan Austria GmbH, Austria), recording the luminescence value of the bacterial strain Escherichia coli K12 TG11 (Ecolum, JSC NVO Immunotech, Russia). Dry matter (DM) digestibility studies were performed using the in vitro method on an “artificial rumen” model using an ANKOM Daisy II incubator unit (AD II; USA). The number of protozoa in ruminal fluid was counted in a Goryaev chamber. The bacterial mass was assessed by differential centrifugation followed by drying. This method is based on differences in the sedimentation rate of particles that differ in size and density. UFP Co3O4 and Mn2O3 at concentrations above 1.5 × 10-5 and 1.9 × 10-3 mol/L, respectively, have a pronounced bactericidal effect, suppressing more than 50% of the luminescence of E. coli K12 TG1. The combined use of UFP metals and plant extract increases the luminescence of the test object, indicating its safety. The combined use of UFP and PB increases the digestibility of feed DM in vitro and the number of protozoa in 1 mL of ruminal fluid; however, the combination of UFP Mn2O3 + PB (13.8%) yielded the best result, which is recommended for further in vivo research. Origanum vulgare extract reduces the toxicity of UFP Co3O4 and Mn2O3 in vitro, indicating that their combined use is safer. Keywords: Co3O4, digestibility, luminescence, Mn2O3, Origanum vulgare, plants, ultrafine particles.
Research Article | 23 Jan 2024
Effects of essential oils on egg production and feed efficiency as influenced by laying hen breed: A meta-analysis
Arif Darmawan, Ergin Öztürk, Emrah Güngör, Şevket Özlü, and Anuraga Jayanegara

Volume-17 | Issue-1 | Article-23 | https://doi.org/10.14202/vetworld.2024.197-206

Preview Abstract
Successful rearing of laying hens to achieve optimal egg production is an endeavor that often faces various constraints and challenges, such as infectious diseases, environmental stressors, and fluctuations in feed quality. The incorporation of essential oils (EOs) into the diet of laying hens has attracted considerable attention in recent years. Therefore, our study aimed to evaluate the efficacy of EO inclusion in laying hen diets by considering the effects of production phase and breed on performance, egg quality, serum biochemistry, gut health, and antioxidant activity. The articles were obtained from the Web of Science, Scopus, Science Direct, and PubMed using the search terms “essential oils,” “laying hens,” and “phytobiotics.” Data from 27 articles and 71 experiments were grouped according to laying hen production phase and breed in the database. The EO levels ranged from 0 to 1000 mg/kg, with thymol and carvacrol being the major EOs. A mixed model was used to analyze the data. Random effects were applied to the treatment, and fixed effects were applied to EO level, production phase, and breed. Egg production, feed intake, feed efficiency, eggshell quality, villus height, crypt depth, superoxide dismutase, and glutathione peroxidase levels increased linearly (p = 0.05) and egg weight and mass increased quadratically (p < 0.05) with increasing EO concentrations. An interaction was observed between the EO level egg production and feed conversion ratio (p = 0.05). Serum glucose, cholesterol, and malondialdehyde levels decreased with increasing EO concentrations (p < 0.05). The inclusion of EOs effectively increased egg production, feed efficiency, egg weight, egg mass, eggshell quality, oxidative enzymes, and intestinal health. In addition, the proportion of dietary EOs in lightweight laying hens was higher than that in semi-heavy-weight laying hens in improving egg production and feeding efficiency. Keywords: antioxidant enzyme, egg production, egg quality, gut health, serum biochemistry.
Research Article | 25 Jan 2024
Isolation of bacteriophages specific to bovine mastitis-causing bacteria and characterization of their lytic activity in pasteurized milk
Napakhwan Imklin, Patinya Patikae, Peekarn Poomirut, Pipat Arunvipas, Rujikan Nasanit, and Somchai Sajapitak

Volume-17 | Issue-1 | Article-24 | https://doi.org/10.14202/vetworld.2024.207-215

Preview Abstract
Bovine mastitis is one of the most serious issues in dairy production. It is caused by contagious and coliform pathogens such as Staphylococcus spp., Escherichia coli, and Klebsiella pneumoniae. In addition, the emergence of drug-resistant bacteria raises urgent concerns in the field of drug treatment, thus requiring the exploration of alternative treatments. Bacteriophage therapy has been shown to be a promising alternative approach for the control of antibiotic-resistant pathogens. In this study, we aimed to isolate phages specific to contagious mastitis and coliform mastitis, characterize the isolated phages, and examine their ability to lyse bacteria in pasteurized milk samples. The Staphylococcus phage vB_Sau-RP15 isolated from raw milk in our previous study was used in this study. Other three phages, vB_Eco-RN12i1, vB_Kpn-RN14i1, and vB_Ssc-RN20i3, were isolated from wastewater using E. coli 5823, K. pneumoniae 194, and Staphylococcus sciuri MM01 as hosts, respectively. The host range and efficiency of plating (EOP) were determined following phage isolation. Moreover, the lysis activities of these phages against their hosts were investigated in pasteurized milk using a multiplicity of infections (MOIs) of 10 and 100 at 37°C. Phages were applied using individual and combination phages. According to the EOP results, all phages showed high specificity to their respective hosts. They are tailed phages with distinct morphologies. Individual phage treatments in spiked pasteurized milk with their respective bacterial hosts significantly reduced the bacterial counts in both MOI conditions during the first 2 h of the treatment (approximately 1–8 log reduction compared to the control). Although these phages specifically infected only their hosts, the phage cocktail resulted in a better result compared to the use of individual phage. However, bacterial regrowth was observed in all experiments, which may be related to the development of phage-insensitive mutants. Our findings suggest that the application of phages could be used to treat bovine mastitis. Phage cocktail is suitable to promote the efficacy of phage treatment in pasteurized milk. However, when considering the use of phages in dairy cows, certain phage properties in raw milk and in vivo and ex vivo should be highlighted to ensure their effectiveness as biocontrol agents for bovine mastitis treatment. Keywords: bovine, Escherichia coli, Klebsiella pneumoniae, mastitis, phage, Staphylococcus.
Research Article | 25 Jan 2024
Kinship analysis of mecA gene of methicillin-resistant Staphylococcus aureus isolated from milk and risk factors from the farmers in Blitar, Indonesia
Aswin Rafif Khairullah, Shendy Canadya Kurniawan, Sri Agus Sudjarwo, Mustofa Helmi Effendi, Agus Widodo, Ikechukwu Benjamin Moses, Abdullah Hasib, Reichan Lisa Az Zahra, Maria Aega Gelolodo, Dyah Ayu Kurniawati, Katty Hendriana Priscilia Riwu, Otto Sahat Martua Silaen, Daniah Ashri Afnani, and Sancaka Cashyer Ramandinianto

Volume-17 | Issue-1 | Article-25 | https://doi.org/10.14202/vetworld.2024.216-225

Preview Abstract
There are numerous reports of subclinical mastitis cases in Blitar, which is consistent with the region’s high milk production and dairy cattle population. Staphylococcus aureus, which is often the cause of mastitis cases, is widely known because of its multidrug-resistant properties and resistance to β-lactam antibiotic class, especially the methicillin-resistant S. aureus (MRSA) strains. This study aimed to molecular detection and sequence analysis of the mecA gene in milk and farmer’s hand swabs to show that dairy cattle are reservoirs of MRSA strains. A total of 113 milk samples and 39 farmers’ hand swab samples were collected from a dairy farm for the isolation of S. aureus using Mannitol salt agar. The recovered isolates were further characterized using standard microbiological techniques. Isolates confirmed as S. aureus were tested for sensitivity to antibiotics. Oxacillin Resistance Screening Agar Base testing was used to confirm the presence of MRSA, whereas the mecA gene was detected by polymerase chain reaction and sequencing. : A total of 101 samples were confirmed to be S. aureus. There were 2 S. aureus isolates that were multidrug-resistant and 14 S. aureus isolates that were MRSA. The mecA gene was detected in 4/14 (28.6%) phenotypically identified MRSA isolates. Kinship analysis showed identical results between mecA from milk and farmers’ hand swabs. No visible nucleotide variation was observed in the two mecA sequences of isolates from Blitar, East Java. The spread of MRSA is a serious problem because the risk of zoonotic transmission can occur not only to people who are close to livestock in the workplace, such as dairy farm workers but also to the wider community through the food chain. Keywords: hand swab, mecA, methicillin-resistant Staphylococcus aureus, milk, public health.
Research Article | 25 Jan 2024
Prevalence of Chlamydophila spp. and Canid herpesvirus-1 in Polish dogs
Kinga Domrazek and Piotr Jurka

Volume-17 | Issue-1 | Article-26 | https://doi.org/10.14202/vetworld.2024.226-232

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Chlamydophila spp. affect Leydig and Sertoli cells by dysregulating spermatogenesis, inducing apoptosis and sperm DNA fragmentation, as well as benign prostate hyperplasia. Canid herpes virus 1 (CHV-1) infection in male dogs is manifested by lesions on the base of the penis and foreskin. There is a lack of information on the influence of these microorganisms on the quality of canine semen. Seroprevalence of Chlamydophila spp. (55%–61%) and CHV-1 (22%–81%) in Europe is high. The prevalence of Chlamydophila spp. and CHV-1 has been evaluated using polymerase chain reaction (PCR) only in Sweden and Croatia, respectively. No positive samples were detected in either case. The aim of this study was to evaluate the epidemiological situation in Polish male dogs (PMDs) to provide a solution to limit the spread of these microorganisms using assisted reproduction techniques or elimination from the reproduction of CHV-1 carriers. In addition, we assessed the semen quality of Chlamydophila spp. carriers and CHV-1 carriers. Cotton swabs were collected from prepuce or semen from each dog (n = 130). Real-time PCR for Chlamydophila spp. and CHV-1, as well as semen analysis, was performed using the computer-assisted semen analysis system. : To the best of our knowledge, this is the first report of Chlamydophila spp. infection in PMD confirmed by real-time PCR. All parameters, except progressive movement in Chlamydophila semen carriers, were normal. The average velocity values for a dog with Chlamydia are detailed. No CHV-1 was detected. The results achieved should be verified on the basis of a larger number of studies. However, the high prevalence of these pathogens in the PMD population has not been established. Keywords: Chlamydia, canid herpes virus 1, dog, herpesvirus, semen.