Thursday, 29 September 2022

Quality control procedure for Coccidial vaccines versus different routes of immunization

Research (Published online: 29-09-2022)
28. Quality control procedure for Coccidial vaccines versus different routes of immunization
Arwa Elnaggar, Hala Mahmoud, and Sahar Saber
Veterinary World, 15(9): 2342-2347

ABSTRACT

Background and Aim: Coccidiosis is an enteric infection caused by a protozoon (Eimeria tenella). Coccidiosis is known to have a negative impact on the economy. Coccidiosis is controlled using anticoccidial drugs, antibiotics, and vaccines. Various coccidial vaccines differ in application technique, attenuation method, and the species used. Coccidial vaccines can be spray or gel-based (Form). This study aimed to compare the effect of application and approaches between spray and gel vaccines for coccidiosis.

Materials and Methods: Specific pathogen-free chicks were vaccinated with different vaccines. Fecal samples were taken on 21 days post-vaccination for vaccine take, and then a challenge test was done on day 21.

Results: Post-vaccination oocyst counts in gel vaccinated groups were more than the spray vaccinated ones as it recorded (1400 and 2200) oocyst/g, but the gel vaccines resulted in lower post vaccinal titer which was (10000 and 12500) oocyst/g. Results of quantitative real-time polymerase chain reaction test post-vaccination were (23.72, 20.29) cycle threshold (CT) for spray vaccines and (18.75, 17.62) CT for gel vaccinated group. By challenging all the experimental groups, the microscopic and macroscopic lesion of gel vaccines resulted in score 1, while spray vaccines groups recorded score 2 and the control non-vaccinated challenged chickens showed score 4. The non-vaccinated/non-challenged group recorded a score of zero.

Conclusion: These results can help poultry producers to decide which delivery system will provide the best results for their production system. The gel vaccines showed a better protection rate and lower shedding, which means more protection of birds and public health.

Keywords: coccidia, Eimeria tenella, anticoccidial drugs and vaccinations, spray.



Effectiveness of Indonesian house dust mite allergenic extract in triggering allergic rhinitis sensitivity in a mouse model: A preliminary study

Research (Published online: 29-09-2022)
27. Effectiveness of Indonesian house dust mite allergenic extract in triggering allergic rhinitis sensitivity in a mouse model: A preliminary study
Yusuf Alif Pratama, Fakhriyah Dinina, Ahmad Dzulfikri Nurhan, Winda Fatma Sari, Chrismawan Ardianto, and Junaidi Khotib
Veterinary World, 15(9): 2333-2341

ABSTRACT

Background and Aim: Perennial allergic rhinitis (AR) is a chronic upper respiratory disease, with inflammation mediated by immunoglobulin E in the nasal mucosa caused by house dust mites. Recently, allergen immunotherapy showed promising allergic healing in patients with a definite history of sensitization. Based on this finding, a product was developed using Indonesian house dust mite (IHDM). This study aimed to optimize the allergenic rhinitis mouse model that was generated using IHDM to test the in vivo sensitivity and safety of this product.

Materials and Methods: Seven groups of mice were used for effectiveness testing – normal, negative control with IHDM challenge, positive control with 0.1% histamine challenge, and AR group by both IHDM-induced sensitization at 12.5, 50, 250, or 500 μg and IHDM challenge. Mice were sensitized by intraperitoneal administration of IHDM once a week for 3 consecutive weeks. Thereafter, the challenge was given intranasally 5 times on alternate days. The number of nose rubbing and sneezing was noted. Eosinophil infiltration was assessed histologically using hematoxylin and eosin staining. The expression of interleukin-5 (IL-5) mRNA in the nasal mucosa was determined using semi-quantitative reverse transcription-polymerase chain reaction.

Results: The induction of AR with IHDM significantly increased the number of nose rubbing and sneezing in the mouse model. Eosinophil infiltration was observed in the nasal mucosa; however, no significant change occurred in the expression of IL-5 mRNA.

Conclusion: Overall, these data indicate that IHDM allergenic extract could be an effective sensitizing agent in a mouse model of AR. Although the use of IHDM is a limitation of this study because other sources of house dust mites might have different effects, this study provides a proper model for immunotherapy effectivity testing for in vivo pre-clinical studies.

Keywords: allergen immunotherapy, allergic healing, allergic rhinitis, Indonesian house dust mites, neglected disease.



Wednesday, 28 September 2022

Enhancement of curcumin level and hepatoprotective effect in rats through antioxidant activity following modification into nanosized particles

Research (Published online: 29-09-2022)
26. Enhancement of curcumin level and hepatoprotective effect in rats through antioxidant activity following modification into nanosized particles
Ni Made Dwi Sandhiutami, Rika Sari Dewi, Sondang Khairani, and Raka Nitya Agasti Putri
Veterinary World, 15(9): 2323-2332

ABSTRACT

Background and Aim: Developing curcumin into nanosized particles is one of the approaches to overcome the limited use of curcumin. This study aimed to prepare curcumin into nanosized particles to increase the curcumin level in the rat's liver and hepatoprotective effect in rats.

Materials and Methods: Curcumin into nanosized particles formulated using ionic gelation method. Rats were divided into four groups (n = 6): Normal, negative, curcumin, and curcumin modified into nanosized particles were treated with 100 mg/ kg body weight orally for 14 days. Hepatic curcumin level was investigated using liquid chromatography with tandem mass spectrometry, antioxidant activity by malondialdehyde (MDA), and hepatoprotective effect by aspartate transaminase (AST), alanine transaminase (ALT), and histopathology.

Results: The curcumin level in the rat's liver in the curcumin group was 12.19 ng/mL, and that in those receiving modified into nanosized curcumin was 209.36 ng/mL. The MDA levels in the normal, negative, curcumin, and curcumin modified into nanosized particles groups were 1.88, 4.87, 3.38, and 1.04 nmol/L, respectively. The AST levels in these groups were 57.12, 130.00, 102.13, and 74.28 IU/L, and the ALT levels were 21.63, 61.97, 39.38, and 28.55 IU/L. The liver histopathology scoring showed that curcumin in nanosized particles was better than curcumin in degeneration of fat, lymphocyte infiltration, and necrosis.

Conclusion: There was a 17 times increase in curcumin level in the liver of rats treated with curcumin modified into nanosized particles. Curcumin modified into nanosized particles showed more significant improvement as antioxidant and hepatoprotector than curcumin.

Keywords: antioxidant, curcumin modified into nanosized particles, hepatoprotective.



Antibacterial effects of oak bark (Quercus robur) and heather herb (Calluna vulgaris L.) extracts against the causative bacteria of bovine mastitis

Research (Published online: 28-09-2022)
25. Antibacterial effects of oak bark (Quercus robur) and heather herb (Calluna vulgaris L.) extracts against the causative bacteria of bovine mastitis
Renāte Šukele, Ingus Skadiņš, Rudīte Koka, and Dace Bandere
Veterinary World, 15(9): 2315-2322

ABSTRACT

Background and Aim: Bovine mastitis has a negative impact on animals, and improper antibiotic use has caused an increase in bacterial resistance. Therefore, medicinal plants could serve as an alternative treatment for this condition. Polyphenols have potential as antibiotic agents. Oak bark has long been used as a medicine and has shown antibacterial effects. Moreover, research on heather plant demonstrated that it has antibacterial properties. This study aimed to assess the antibacterial effects of oak (Quercus robur) bark and heather (Calluna vulgaris L.) herb extracts against common bovine mastitis pathogens.

Materials and Methods: Dried oak bark and heather herb were used to prepare extracts using 30%, 50%, and 70% ethanol and acetone as solvents. Their polyphenol content was determined using the Folin–Ciocalteu method. Bovine mastitis-inducing clinical isolates of Escherichia coliStreptococcus agalactiaeStreptococcus uberisSerratia liquefaciensStaphylococcus aureus, and reference cultures of S. aureus and E. coli were used for antibacterial tests. All extracts were screened through a disk diffusion test to ascertain their antibacterial effects, and the minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined for the most effective extracts.

Results: Oak bark extracts had variable antibacterial effects against S. aureus and Streptococcus strains, but no statistically significant difference was observed in activity against E. coli. The disk diffusion test showed that the oak bark extracts obtained using acetone and ethanol at 30% yielded the best results. However, the 70% acetone oak extract alone affected all types of bacteria. Further antibacterial tests of 70% acetone and 30% ethanol oak extracts revealed that the lowest MIC and MBC scores were against S. aureus strains and E. coli reference cultures. Conversely, the heather herb extracts exhibited broader activity against all types of bacteria, although better results were observed against Gram-positive bacteria. There was also a negative correlation between solvent concentration and antibacterial effect (p < 0.05, r = –0.507). The highest inhibition zone scores and broadest spectrum were observed in samples prepared in 30% ethanol. There was no statistically significant correlation between the phenolic content of plants and their antibacterial effects.

Conclusion: Oak bark and heather extracts could be used as potential antibacterial agents against bovine mastitis pathogens.

Keywords: antibacterial, bovine mastitis, Escherichia coli, heather herb, in vitro, oak bark, Staphylococcus aureusStreptococcus.



Monday, 26 September 2022

Molecular detection and dense granule antigen 6 genotyping of feline Toxoplasma gondii in Phayao, Thailand

Research (Published online: 26-09-2022)
24. Molecular detection and dense granule antigen 6 genotyping of feline Toxoplasma gondii in Phayao, Thailand
Chittakun Suwancharoen, Chorpaka Phuangsri, Khanuengnij Prakhammin, and Ornampai Japa
Veterinary World, 15(9): 2309-2314

ABSTRACT

Background and Aim: Globally, toxoplasmosis is an important zoonotic parasite infection of many warm-blooded animals (including humans). Toxoplasma gondii oocysts are widespread, and their contamination can be primarily attributed to the members of the Felidae family. This study aimed to estimate the prevalence and determine the dense granule antigen 6 (GRA6) genotype of T. gondii among domestic cats in the Phayao Province, Thailand.

Materials and Methods: A total of 124 fecal samples were collected from owned cats in the Muang district, Phayao, Thailand, from January to December 2020. Fecal samples were tested for the presence of T. gondii DNA using targeted B1 gene polymerase chain reaction (PCR) amplification, and positive samples were subsequently analyzed for their T. gondii genotype through PCR-restriction fragment length polymorphism (RFLP) analysis and sequencing of the GRA6 gene.

Results: Among the 124 samples, 46 (37.1%) were tested positive for T. gondii. Only 10 positive DNA samples were successfully amplified for the GRA6 marker. Subsequent PCR-RFLP and sequence analyses indicated that all T. gondii isolates from cats in Phayao belonged to GRA6 genotype I.

Conclusion: Data revealed that toxoplasmosis is remarkably distributed among (studied) domestic cats in Phayao, Thailand. Moreover, the virulent GRA6 allele was found to be circulated among domestic cats in this area. However, no significant correlation was observed between infection rates and different risk factors, which indicated that pet cats of any age, gender, or breed have similar risks of being infected with T. gondii. Our results further suggested that infective oocysts of T. gondii are widely distributed and that environmental contamination with these oocysts will introduce more risks of disease transmission to humans and other animals.

Keywords: domestic cats, genotype, granule antigen 6, Toxoplasma gondii, toxoplasmosis.



Effects of probiotic (Lactobacillus plantarum and Bacillus subtilis) supplementation on mortality, growth performance, and carcass characteristics of native Vietnamese broilers challenged with Salmonella Typhimurium

Research (Published online: 26-09-2022)
23. Effects of probiotic (Lactobacillus plantarum and Bacillus subtilis) supplementation on mortality, growth performance, and carcass characteristics of native Vietnamese broilers challenged with Salmonella Typhimurium
Tran Van Be Nam, Luu Huynh Anh, Huynh Tan Loc, Chau Thi Huyen Trang, Nguyen Thiet, Ly Thi Thu Lan, Tran Hoang Diep, Nguyen Hong Xuan, and Nguyen Trong Ngu
Veterinary World, 15(9): 2302-2308

ABSTRACT

Background and Aim: Probiotic species have been proven to be beneficial on broiler performance; however, most studies have focused on industrial chickens with fast growth, whereas little information concerning the use of these species on native chickens is available. This study aimed to investigate the effects of probiotics Lactobacillus plantarum (LP) and Bacillus subtilis (BS) on the mortality, growth rate, and carcass characteristics in native Noi chickens challenged with Salmonella Typhimurium.

Materials and Methods: We divided 420 1-day-old Noi chicks into seven different treatment groups (n = 60): negative control (no S. Typhimurium, no probiotics or antibiotics); positive control (PC, S. Typhimurium infection, no probiotics or antibiotics); and S. Typhimurium infection and supplementation with LP, BS, LP + BS, enrofloxacin, and commercial probiotics, respectively. Treatment was for 96 days, and the chicks were orally challenged with S. Typhimurium at 22 days old.

Results: No deaths occurred during the 4 weeks post-infection in the negative control, LP, or LP+BS groups. The PC group had the highest mortality rate (20%). Re-isolation of S. Typhimurium from the liver, spleen, and heart showed reduced bacterial counts at 1 week post-infection in the LP, BS, and LP + BS groups. The lowest body weight gain was observed in the PC group (949 g/bird), and chicks in the LP group gained 1148 g/bird. An improved feed conversion ratio was noted in the groups receiving probiotic supplementation (3.42–3.50 kg feed/kg gain). There was little evidence that probiotics affected carcass percentage and related parameters, such as breast, thigh and drumstick, and wings.

Conclusion: Lactobacillus plantarum or BS dietary supplementation to native Noi broilers resulted in a lower mortality rate and improved body weight gain but did not affect carcass characteristics.

Keywords: Bacillus subtilis, growth, Lactobacillus plantarum, mortality, Noi chicken.



Sunday, 25 September 2022

First study on virulence genes, antimicrobial resistance, and integrons in Escherichia coli isolated from cage, free-range, and organic commercial eggs in Phayao Province, Thailand

Research (Published online: 25-09-2022)
22. First study on virulence genes, antimicrobial resistance, and integrons in Escherichia coli isolated from cage, free-range, and organic commercial eggs in Phayao Province, Thailand
Achiraya Siriphap, Chittakun Suwancharoen, Watchara Laenoi, Parinya Kraivuttinun, Orasa Suthienkul, and Watsawan Prapasawat
Veterinary World, 15(9): 2293-2301

ABSTRACT

Background and Aim: Antimicrobial resistance (AMR) is a global problem that affects human and animal health, and eggs can act as a vehicle for pathogenic and non-pathogenic resistant bacteria in the food chain. Escherichia coli is an indicator of food contamination with fecal materials as well as the occurrence and levels of AMR. This study aimed to investigate the presence of AMR, integrons, and virulence genes in E. coli isolated from eggshell samples of three egg production systems, from supermarkets in Thailand.

Materials and Methods: A total of 750 hen's egg samples were purchased from supermarkets in Phayao Province: Cage eggs (250), free-range eggs (250), and organic eggs (250). Each sample was soaked in buffered peptone water (BPW), and the BPW samples were incubated at 37°C for 18–24 h. All samples were tested for E. coli by the standard conventional culture method. Then, all identified E. coli were tested for antimicrobial susceptibility to 15 antimicrobial agents by the agar disk diffusion method. All E. coli strains were subsequently found to have virulence genes and Classes 1 and 2 integrons by polymerase chain reaction.

Results: Among the eggshell samples, 91 samples were identified as having E. coli (cage eggs, 24 strains; free-range eggs, 27 strains; and organic eggs, 40 strains). Then, among the E. coli strains, 47 (51.6%) were positive for at least one virulence gene. The proportion of AMR in the eggshell samples was 91.2% (83/91), and streptomycin (STR), ampicillin (AMP), and tetracycline (TET) had a high degree of resistance. Among the E. coli strains, 27 (29.7%) strains were positive for class 1 or 2 integrons, and integron-positive strains were commonly found in STR-, AMP-, and TET-resistant strains. Multidrug resistance (MDR) was detected in 57.1% (52/91) of the E. coli strains, with STR-AMP-TET (5.5%) as the most frequent pattern. The proportion of MDR in cage eggs was 75.0% (18/24), which was higher than in both free-range and organic eggs. On the other hand, 53.2% (25/47) of E. coli carrying virulence genes had MDR, distributed across the production systems as follows: Cage eggs, 76.9% (10/13); free-range eggs, 63.6% (7/11); and organic eggs, 34.8% (8/23).

Conclusion: Escherichia coli was detected in eggshell samples from all three egg production systems. The high level of virulence genes, AMR, and integrons indicated the possibility of dissemination of AMR among pathogenic and commensal E. coli through eggshells. These findings could be a major concern to farmers, food handlers, and consumers, especially regarding raw egg consumption.

Keywords: antimicrobial resistance, eggshells, Escherichia coli, integrons, virulence.