Bacteriophage efficacy in controlling swine enteric colibacillosis pathogens: An in vitro study

Research (Published online: 12-12-2022)

9. Bacteriophage efficacy in controlling swine enteric colibacillosis pathogens: An in vitro study

Techaphon Songphasuk, Napakhwan Imklin, Pattaraporn Sriprasong, Yonlayong Woonwong, Rujikan Nasanit, and Somchai Sajapitak

Veterinary World, 15(12): 2822-2829

ABSTRACT

Background and Aim: Swine enteric colibacillosis caused by Escherichia coli is a major problem in the swine industry, causing diarrhea among swine and resulting in substantial financial losses. However, efforts to counter this disease are impeded by the increase in antimicrobial resistance (AMR) worldwide, so intensive research is being conducted to identify alternative treatments. This study isolated, characterized, and evaluated the efficacy of bacteriophages to control pathogens causative of swine enteric colibacillosis.

Materials and Methods: Five sewage samples were collected from different areas of a swine farm in Suphanburi province, Thailand and the bacteriophages were enriched and isolated, followed by purification by the agar overlay method using E. coli RENR as the host strain. The selected phages were characterized by evaluating their morphology, while their specificity was verified by the host range test. The efficiency of plating and multiplicity of infection (MOI) were also determined.

Results: Four selected phages, namely, vB_Eco-RPNE4i3, vB_Eco-RPNE6i4, vB_Eco-RPNE7i1, and vB_Eco-RPNE8i3, demonstrated different patterns of host range and phage efficiency. They significantly decreased E. coli concentration at the tested MOIs (0.01–100) from 1 h onward. However, bacterial regrowth was observed in all phage treatments.

Conclusion: This study shows the potential of using phages as an alternative treatment for swine enteric colibacillosis. The obtained results demonstrated that the selected phages had a therapeutic effect against pathogens causative of swine enteric colibacillosis. Therefore, phages could be applied as an alternative treatment to control specific bacterial strains and reduce AMR arising from the overuse of antibiotics.

Keywords: bacteriophages, colibacillosis, diarrhea, Escherichia coli, swine.

Molecular characterization of Newcastle disease virus vaccines in Nigeria

Research (Published online: 10-12-2022)

8. Molecular characterization of Newcastle disease virus vaccines in Nigeria

Mohammed Usman Sajo, Lawal Sa'idu, Maman Moutari Souley, and Olusegun Adesina Fagbohun

Veterinary World, 15(12): 2816-2821

ABSTRACT

Background and Aim: Newcastle disease (ND) caused by ND virus (NDV) is a serious impediment to effective poultry production in developing countries such as Nigeria. Despite employing vaccination and other control measures to curtail this disease, its severe forms still persist. This study aimed to confirm the virus strains in the NDV vaccine brands commonly used in Nigeria.

Materials and Methods: We employed reverse-transcription polymerase chain reaction (RT-PCR), sequencing, and sequence analysis to characterize NDV strains in four NDV vaccines commonly used in Nigeria. Fragments of 300 bp from NDV fusion genes from the vaccines were amplified. Polymerase chain reaction products were sequenced and analyzed using multiple sequence alignment and phylogenetic analyses to characterize the vaccine viruses as pathotypes.

Results: All the vaccines gave positive results, confirming the presence of NDV. Multiple sequence alignment and phylogenetic analyses revealed that two of the vaccines had the lentogenic pathotype, while the other two had the mesogenic or velogenic pathotype.

Conclusion: This study provides information to facilitate strategies for regular control of the quality of vaccines in Nigeria.

Keywords: Newcastle disease virus, Nigeria, polymerase chain reaction, vaccines.

Impact of serum C-reactive protein level as a biomarker of cancer dissemination in canine lymphoid neoplasia

Research (Published online: 10-12-2022)

7. Impact of serum C-reactive protein level as a biomarker of cancer dissemination in canine lymphoid neoplasia

Nawin Manachai, Duangchanok Umnuayyonvaree, Panitnan Punyathi, Anudep Rungsipipat, and Kasem Rattanapinyopituk

Veterinary World, 15(12): 2810-2815

ABSTRACT

Background and Aim: C-reactive protein (CRP) is a highly sensitive but non-specific acute phase protein that has been widely used to predict the biological behavior of patients with cancer. This study aimed to examine the significance of the serum CRP biomarker in predicting the prognosis of dogs with lymphoma.

Materials and Methods: Blood samples (5 mL) were collected from 34 lymphoma dogs and control healthy dogs. Canine lymphoma clinical staging was classified using the World Health Organization (WHO) criteria. All lymphoma dogs were reclassified into two groups based on the disease stage. Stages IV and V were designated as advanced stages, and Stages I–III were designated as other stages. The serum CRP level was then determined using a commercial canine CRP fluorescent immunoassay kit and routine hematological and biochemical analyses. C-reactive protein levels, circulating inflammatory parameters, such as neutrophil-to-lymphocyte ratio, lymphocyte-to-monocyte ratio, and platelet-to-lymphocyte ratio, and albumin levels were compared between advanced stages (IV and V) and Stages I to III using Mann–Whitney U tests. Receiver operating characteristic (ROC) curves were also generated to determine the cutoff value, diagnostic sensitivity, and specificity of the CRP level.

Results: A prospective study identified 34 dogs recently diagnosed with canine lymphoma. C-reactive protein levels were significantly higher in lymphoma dogs in advanced stages (IV and V) than in lymphoma dogs in Stages I–III. According to the ROC curve analysis, a CRP cutoff level of 54.1 mg/L indicates advanced-stage canine lymphoma, which can be used as a biomarker to predict cancer dissemination.

Conclusion: Serum CRP concentrations can assist clinical decision-making on the WHO stage in lymphoma dogs in clinical applications. The limitations of this study include a small number of lymphomas and no survival analysis.

Keywords: advanced stage lymphoma, biomarker, dogs, serum C-reactive protein.

Phylogenetic analysis and antibiotic resistance of Escherichia coli isolated from wild and domestic animals at an agricultural land interface area of Salaphra wildlife sanctuary, Thailand

Research (Published online: 08-12-2022)

6. Phylogenetic analysis and antibiotic resistance of Escherichia coli isolated from wild and domestic animals at an agricultural land interface area of Salaphra wildlife sanctuary, Thailand

Taksaon Duangurai, Amporn Rungruengkitkul, Thida Kong-Ngoen, Witawat Tunyong, Nathamon Kosoltanapiwat, Poom Adisakwattana, Muthita Vanaporn, Nitaya Indrawattana, and Pornpan Pumirat

Veterinary World, 15(12): 2800-2809

ABSTRACT

Background and Aim: Domestic and wild animals are important reservoirs for antibiotic-resistant bacteria. This study aimed to isolate Escherichia coli from feces of domestic and wild animals at an agricultural land interface area of Salaphra Wildlife Sanctuary, Thailand, and study the phylogenic characteristics and antibiotic resistance in these isolates.

Materials and Methods: In this cross-sectional, descriptive study, we randomly collected ground feces from free-ranging wild animals (deer and elephants) and domestic animals (cattle and goats). All fecal samples were inoculated onto MacConkey agar plates, and lactose-fermenting colonies were identified as E. coli. Antibiotic susceptibility of the E. coli isolates was determined using the disc diffusion method. Polymerase chain reaction assays were used to detect antibiotic resistance and virulence genes.

Results: We obtained 362 E. coli isolates from the collected fecal samples. The E. coli isolates were categorized into four phylogenetic groups according to the virulence genes (chuA, vjaA, and TspE4C2). Phylogenetic Group D was predominant in the deer (41.67%) and elephants (63.29%), whereas phylogenetic Group B1 was predominant in the cattle (62.31%), and phylogenetic Groups A (36.36%) and B2 (33.33%) were predominant in the goats. Antibiotic susceptibility testing revealed that most antibiotic-resistant E. coli were isolated from domestic goats (96.96%). Among the 362 E. coli isolates, 38 (10.5%) were resistant to at least one antibiotic, 21 (5.8%) were resistant to two antibiotics, and 6 (1.66%) were resistant to three or more antibiotics. Ampicillin (AMP) was the most common antibiotic (48.48%) to which the E. coli were resistant, followed by tetracycline (TET) (45.45%) and trimethoprim-sulfamethoxazole (3.03%). One isolate from an elephant was resistant to five antibiotics: AMP, amoxicillin, sulfisoxazole, TET, and ciprofloxacin. Determination of antibiotic resistance genes confirmed that E. coli isolates carried antibiotic resistance genes associated with phenotypic resistance to antibiotics. Most antibiotic-resistant E. coli belonged to phylogenic Groups A and B1, and most non-resistant E. coli belonged to phylogenic Groups B2 and D.

Conclusion: Monitoring E. coli isolates from wild and domestic animals showed that all four phylogenic groups of E. coli have developed antibiotic resistance and are potential sources of multidrug resistance. High levels of antibiotic resistance have been linked to domestic animals. Our results support strengthening surveillance to monitor the emergence and effects of antibiotic-resistant microorganisms in animals.

Keywords: antibiotic resistance, domestic animal, Escherichia coli, phylogenic groups, phylogeny, wild animal.

Hematology and toll-like receptors 2 and 4 and lipopolysaccharide-induced tumor necrosis factor-α factor gene expression in peripheral blood mononuclear cells of Thai indigenous chickens

Research (Published online: 07-12-2022)

5. Hematology and toll-like receptors 2 and 4 and lipopolysaccharide-induced tumor necrosis factor-α factor gene expression in peripheral blood mononuclear cells of Thai indigenous chickens

Chananphat Tantikositruj, Asep Gunawan, Muhammad Jasim Uddin, Wirawan Nuchchanart, Chaiwat Boonkaewwan, Watchara Laenoi, and Autchara Kayan

Veterinary World, 15(12): 2795-2799

ABSTRACT

Background and Aim: Toll-like receptors (TLRs) play crucial roles in the early phase of infection in the innate immune response against bacteria, viruses, fungi, and parasites. Lipopolysaccharide-induced tumor necrosis factor-α factor (LITAF) is an essential transcription factor that regulates the immune system, apoptosis, and inflammatory cytokines. This study aimed to determine the hematological profile reflecting the immune response related to TLR2 and TLR4 and LITAF gene expression in Thai indigenous chickens.

Materials and Methods: Blood samples (2 mL) were randomly obtained from three chicken breeds (black-boned chicken, Fah Luang chicken, and Pradu Hang Dam chicken) at 16 weeks of age (n = 5 per breed). The hematological profile and mRNA expression within the peripheral blood mononuclear cells (PBMCs) were determined by hematological analysis and quantitative real-time polymerase chain reaction (qRT-PCR).

Results: The hematological profile differed significantly in terms of red blood cells (RBCs), hemoglobin, and white blood cells (WBCs) (p < 0.05). Black-boned chicken and Fah Luang chicken had lower RBC levels than Pradu Hang Dam chicken. Fah Luang chicken had lower hemoglobin than Pradu Hang Dam chicken. However, Fah Luang chicken had higher WBC levels than Pradu Hang Dam chicken. Hematocrit, heterophils, basophils, eosinophils, lymphocytes, and monocytes did not differ significantly among the groups (p > 0.05). According to qRT-PCR, the expression of the TLR2 gene did not differ significantly among the groups (p > 0.05), while TLR4 and LITAF gene expression did (p < 0.05). Toll-like receptor 4 and LITAF genes were most highly expressed in Fah Luang chicken.

Conclusion: The PBMCs of Thai indigenous chickens showed evidence of TLR4 and LITAF gene expression, with higher expression levels observed in Fah Luang chicken. From this preliminary study, it is concluded that TLR4 and LITAF genes might play roles in the main immune system response in Thai indigenous chickens.

Keywords: blood hematology, gene expression, immune, Thai indigenous chicken.

Multifarious feed additives on lamb performance on Kuwait farms

Research (Published online: 05-12-2022)

4. Multifarious feed additives on lamb performance on Kuwait farms

Hana'a Burezq and Faten Khalil

Veterinary World, 15(12): 2785-2794

ABSTRACT

Background and Aim: A change in the livestock feeding strategy is of utmost importance for the stability of animal health and sustainable livestock productivity to overcome the problem of subsiding the environmental effects of sheep production. Supplementing dietary feed with safe and efficient additives provides optimal animal performance and maximizes productivity. This study aimed to assess the effects of adding various feed additives to lamb rations for optimizing feed efficiency in weaned lambs for meat production in Kuwait.

Materials and Methods: The feed additives, namely, ammonium chloride, urea, algae, fishmeal, and humic acid, were investigated on the physical performance of lambs for their effect on body weight, length, height, and waist length. The total feed consumption rate and feed efficiency were also measured. Each treatment comprising five healthy lambs was randomly allocated into six treatments comprising 30 lambs. The six treatments were the basal ration supplemented with ammonium chloride (50–100 g/day/head), urea (30 g/day/head), fishmeal (35 g/day/head), algae (Spirulina platensis) powder (50 g/day/head), humic acid (2.5 g/day/head), control group with only basal ration. The study was conducted for around 27 months and the data were recorded once in 2 weeks.

Results: The results indicated a positive elevation in the physique of lambs with all tested additives, showing an affirmative insignia for lamb fattening. The growth parameters in terms of augmented length, height, and waist length of lambs' bodies amplified significantly with ammonium chloride and fishmeal supplement, while the other additives reported a non-significant increment. The feed consumption was significantly elevated for ammonium chloride, algae, and fishmeal supplementation, while humic acid was recorded the least. Concerning feed efficiency of young lambs, fish meal and ammonium chloride were reported best, followed by urea. In contrast, algae and humic acid exhibited a non-significant effect on feed efficiency.

Conclusion: This study exposed noteworthy influence on a lamb body's performance with the addition of fish meal and ammonium chloride in lamb rations, trailed by urea and algae.

Keywords: ammonium chloride, efficiency, feed additives, fishmeal, performance, urea.

Evaluation of a vaccine candidate isolated from Cryptosporidium parvum oocyst in mice

Research (Published online: 05-12-2022)

3. Evaluation of a vaccine candidate isolated from Cryptosporidium parvum oocyst in mice

Dina Aboelsoued, Hend H. A. M. Abdullah, Kadria N. Abdel Megeed, Soad E. Hassan, and Nagwa I. Toaleb

Veterinary World, 15(12): 2772-2784

ABSTRACT

Background and Aim: Cryptosporidiosis is a leading cause of diarrheal disease worldwide and is an animal and public health burden. This study aimed to evaluate the protective potential of affinity-purified Cryptosporidium parvum oocyst antigen as a vaccine candidate according to fecal oocyst shedding, humoral and cellular immune responses, histopathological changes, and the number of parasite developmental stages in ileal and hepatic tissues.

Materials and Methods: We isolated oocysts from naturally infected buffalo calves and identified them molecularly as C. parvum isolates (GenBank: ON730707 and ON730708) by targeting the Cryptosporidium oocyst wall protein gene. We propagated the C. parvum oocysts in mice. In addition, we prepared crude antigen from the isolated oocysts by purification using cyanogen bromide-activated Sepharose-4B affinity chromatography coupled with rabbit hyperimmune serum. Then, we divided 81 parasite-free mice into three groups: (1) non-vaccinated non-infected mice, (2) mice orally infected with 1 × 105 C. parvum oocysts on week 4 of the experiment, and (3) mice immunized twice with 40 μg/kg of the purified fraction at 2-week intervals. Then, we challenged the vaccinated group with C. parvum oocysts after 2 weeks, and the positive control group was infected at the same time.

Results: We observed a prolonged prepatent period and decreased oocyst shedding in the vaccinated infected mice compared with the non-vaccinated infected mice (t < 0.001). The vaccinated mice had significantly higher immunoglobulin G levels than those in the other two groups at all examined weeks. In addition, the production of cytokines interferon-gamma, interleukin (IL)-10, IL-12, and IL-15 was activated post-vaccination. After the challenge, all tested cytokines were significantly increased (p < 0.001) in the two infected groups compared with the non-vaccinated non-infected group, with the highest levels in the vaccinated infected group. Vaccinated infected mice exhibited significantly fewer pathological lesions in the ileum and liver than non-vaccinated infected mice, which showed prominent histopathological lesions. Endogenous developmental stages of C. parvum indicated that the ileum was more parasitized than the liver and that vaccination resulted in a lower number of oocysts in ileal and hepatic tissues (p < 0.05).

Conclusion: Our prepared affinity-purified vaccine candidate could be promising in protecting against cryptosporidiosis.

Keywords: affinity chromatography, Cryptosporidium parvum, cytokines, enzyme-linked immunosorbent assay, histopathology, polymerase chain reaction, vaccine.