Molecular epidemiology and antimicrobial resistance of Salmonella isolates from broilers and pigs in Thailand

Research (Published online: 23-08-2019)

20. Molecular epidemiology and antimicrobial resistance of Salmonella isolates from broilers and pigs in Thailand

Dusadee Phongaran, Seri Khang-Air and Sunpetch Angkititrakul

Veterinary World, 12(8): 1311-1318

ABSTRACT

Aim: This study aimed to determine the prevalence and antimicrobial resistance pattern of Salmonella spp., and the genetic relatedness between isolates from broilers and pigs at slaughterhouses in Thailand.

Materials and Methods: Fecal samples (604 broilers and 562 pigs) were collected from slaughterhouses from April to July 2018. Salmonella spp. were isolated and identified according to the ISO 6579:2002. Salmonella-positive isolates were identified using serotyping and challenged with nine antimicrobial agents: Amoxicillin/clavulanate (AMC, 30 μg), ampicillin (AMP, 10 μg), ceftazidime (30 μg), chloramphenicol (30 μg), ciprofloxacin (CIP, 5 μg), nalidixic acid (NAL, 30 μg), norfloxacin (10 μg), trimethoprim/sulfamethoxazole (SXT, 25 μg), and tetracycline (TET, 30 μg). Isolates of the predominant serovar Salmonella Typhimurium were examined for genetic relatedness using pulsed-field gel electrophoresis (PFGE).

Results: Salmonella was detected in 18.05% of broiler isolates and 37.54% of pig isolates. The most common serovars were Kentucky, Give, and Typhimurium in broilers and Rissen, Typhimurium, and Weltevreden in pigs. Among broilers, isolates were most commonly resistant to antibiotics, NAL, AMP, TET, AMC, and CIP. Pig isolates most commonly exhibited antimicrobial resistance against AMP, TET, and SXT. Based on PFGE results among 52 S. Typhimurium isolates from broilers and pigs, a high genetic relatedness between broiler and pig isolates (85% similarity) in Cluster A and C from PFGE result was identified.

Conclusion: The results revealed high cross-contamination between these two animal species across various provinces in Thailand.

Keywords: antimicrobial resistance, broilers, pigs, pulsed-field gel electrophoresis, Salmonella spp.

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Identification and classification of honey's authenticity by attenuated total reflectance Fourier-transform infrared spectroscopy and chemometric method

Research (Published online: 23-08-2019)

19. Identification and classification of honey's authenticity by attenuated total reflectance Fourier-transform infrared spectroscopy and chemometric method

Muhamad Sahlan, Seffiani Karwita, Misri Gozan, Heri Hermansyah, Masafumi Yohda, Young Je Yoo and Diah Kartika Pratami

Veterinary World, 12(8): 1304-1310

ABSTRACT

Background and Aim: The authentication of honey is important to protect industry and consumers from such adulterated honey. However, until now, there has been no guarantee of honey's authenticity, especially in Indonesia. The classification of honey is based on the bee species (spp.) that produces it. The study used honey from sting bee Apis spp. and stingless bee Tetragonula spp. based on the fact that the content off honey produced between them has differences. Authenticating honey with currently available rapid detection methods, such as 13C nuclear magnetic resonance analysis, is costly. This study aimed to develop an inexpensive, fast, precise, and accurate classification method for authenticating honey.

Materials and Methods: In this study, we use attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy with wavelengths ranging between 550 and 4000 cm-1 as an alternative analysis method, which is relatively less expensive. The spectra of authentic and fake honey samples were obtained using ATR-FTIR and plotted using chemometric discriminant analysis. The authentic honey samples were acquired from a local Indonesian breeder of honey bees, while the fake honey samples were made from a mixture of water, sugar, sodium bicarbonate, and authentic honey. Data were collected using Thermo Scientific's OMNIC FTIR software and processed using Thermo Scientific's TQ Analyst software.

Results: Our method effectively classified the honey as authentic or fraudulent based on the FTIR spectra. To authenticate the honey, we formed two classes: Real honey and fake honey. The wavelengths that can best differentiate between these two classes correspond to four regions: 1600-1700 cm-1; 1175-1540 cm-1; 940-1175 cm-1; and 700-940 cm-1. Similarly, for classification purpose, we formed two classes: Apis spp. and Tetragonula spp. The wavelength region that can best classify the samples as belonging to the Apis spp. or Tetragonula spp. class is explicitly within the range of 1600-1700 cm-1.

Conclusion: This study successfully demonstrated a method to rapidly and accurately classify and authenticate honey. ATR-FTIR is a useful tool to test the authenticity of honey.

Keywords: Apis spp., attenuated total reflectance Fourier transform infrared, discriminant, spectrum, Tetragonula spp.

Effect of the pH in the enrichment of X or Y sex chromosome-bearing sperm in bovine

Research (Published online: 23-08-2019)

18. Effect of the pH in the enrichment of X or Y sex chromosome-bearing sperm in bovine

Nidhi P. Raval, Tejas M. Shah, Linz-Buoy George and Chaitanya G. Joshi

Veterinary World, 12(8): 1299-1303

ABSTRACT

Background and Aim: Studies have shown that the pH of the vagina during the course of fertilization may influence the migration of X- and Y-bearing spermatozoa and thus leading to skewness in the sex of the offspring. Hence, this study was carried out to check the effect of the pH in the enrichment of X or Y sex chromosome-bearing sperm in bovine (Bos indicus).

Materials and Methods: To check the effect of pH in the enrichment of X or Y sex chromosome-bearing sperm in bovine, we used buffers of various pH ranging from 5.5 to 9.0 for swim-up procedure of sperm sample and collected upper and bottom fraction from the same buffer and checked the abundance of X- and Y-bearing spermatozoa by droplet digital polymerase chain reaction using X- and Y-chromosome-specific DNA probe.

Results: The abundance of X- and Y-bearing spermatozoa was not differed significantly in either of the fraction collected.

Conclusion: Thus, it appears to be unlikely that an immediate impact of pH on sperm can be a solitary impact on the sex of offspring in bovine.

Keywords: droplet digital polymerase chain reaction, spermatozoa, swim-up.

Field safety and efficacy of a unique live virus vaccine for controlling avian encephalomyelitis and fowlpox in poultry

Research (Published online: 23-08-2019)

17. Field safety and efficacy of a unique live virus vaccine for controlling avian encephalomyelitis and fowlpox in poultry

Girish Sarma, Barry A. Kersting and Gary Spina

Veterinary World, 12(8): 1291-1298

ABSTRACT

Background and Aim: Infection of commercial poultry with avian encephalomyelitis (AE) and fowlpox (FP) virus causes heavy economic loss in endemic areas. Although vaccines are routinely used to control these two diseases, the problem still persists almost all over the world. This study aimed to evaluate safety and efficacy of a unique AE + FP + pigeon pox (PP) live virus vaccine in layer-type chickens under both laboratory and field conditions.

Materials and Methods: The study was conducted using 289 specific-pathogen-free (SPF) chickens under the laboratory conditions and 185,648 commercial layer-type chickens under field conditions. In two consecutive laboratory trials, 8-week-old SPF chickens were vaccinated with the AE + FP + PP live virus vaccine through wing web route and challenged against virulent strains of FP and AE viruses at 3-week post-vaccination (WPV). Challenged chickens were observed for disease protection for 10-21 days. For field safety trials, commercial layer-type chickens in three different geographical areas in the USA were vaccinated with the AE + FP + PP vaccine and observed daily up to 21 days for vaccine "take". adverse reactions, and mortality.

Results: The vaccine was found safe and efficacious under both laboratory and field conditions. Vaccine "take" and protection against FP challenge were 100%. Average protection against AE challenge was 97%. Mean AE enzyme-linked immunosorbent assay (ELISA) antibody titer in the field vaccinated chickens was >1200 at 10 WPV. Average daily post-vaccination mortality in the field vaccinated chickens was 0.04%. So far, more than 400 million chickens in the USA have been vaccinated with this vaccine. No vaccine-associated adverse reactions, other safety issues, or immunity breakdown cases in the vaccinated flocks due to field virus infection have been reported.

Conclusion: This unique vaccine containing AE, FP, and PP viruses in a single preparation was found to be safe and efficacious in controlling the diseases caused by the virulent field strains of AE and FP. Besides being safe and efficacious, this vaccine also offered distinct advantages over the traditional vaccination practices in controlling these two diseases in poultry.

Keywords: avian encephalomyelitis, efficacy, field safety, fowlpox, live virus vaccine, pigeon pox, protection.

Knowledge and behavior of cattle and sheep owners and herders regarding foot-and-mouth disease in Northern Algeria

Research (Published online: 21-08-2019)

16. Knowledge and behavior of cattle and sheep owners and herders regarding foot-and-mouth disease in Northern Algeria

Ratiba Baazizi, Nora Mimoune, M'Hamed El Mokhefi, Muslim Raza, Amina Chahed and Tanveer Hussain

Veterinary World, 12(8): 1285-1290

ABSTRACT

Background and Aim: Foot-and-mouth disease (FMD) has been occurring in Algeria since 2014, when an outbreak was announced in Setif, a district in the eastern region of the country. The problem was apparently resolved with the help of vaccination. However, in 2015, 2016, and 2018, FMD recurred. The veterinary authorities and media educated breeders on how to recognize the clinical signs and how to report the disease. This study aimed to evaluate the knowledge and recognition of FMD by farmers and breeders. Moreover, an assessment of the behavior of cattle and sheep owners and herders following FMD cases is examined.

Materials and Methods: A cross-sectional survey was conducted from June to October 2018 to evaluate the perception of cattle and sheep owners and breeders regarding FMD in the Northern regions of Algeria, using questionnaires.

Results: One hundred questionnaires were distributed; 71 were collected. Data showed that all the responders claimed to know about the disease, while more than half of the owners/herders claimed that they knew the clinical symptoms of FMD and mentioned fever, hypersalivation, lameness, and vesicles. Fewer than half (42%) (30/71) took some measures to prevent the disease, while more than half (58%) (41/71) did not take any measures in 2018. No one claimed to have reported the disease to authorities in 2018, while more than half had done so in 2014.

Conclusion: It appears that experienced farmers recognized the clinical signs of FMD, while an academic background was not conclusively necessary for the identification of the clinical signs of the disease. Concerning the assessment of risk-associated behavior in the event of FMD occurrence, the responses of the breeders were not significantly different from those of risk-associated behaviors in the event of an epidemic. Farmers and breeders expressed similarity in terms of communicating the appearance of the disease in their livestock; the majority of them seemed to be aware of the importance of reporting the disease to local authorities, especially in 2014, when the disease first occurred. This behavior is encouraged by refund and technical assistance policies by the veterinary authorities, but in 2018, no disease was reported due to fear of slaughtering and economic loss.

Keywords: cattle and sheep farmers, clinical signs, foot-and-mouth disease, knowledge and seniority, survey.

Risk factors associated with viral nervous necrosis in hybrid groupers in Malaysia and the high similarity of its causative agent nervous necrosis virus to reassortant red-spotted grouper nervous necrosis virus/striped jack nervous necrosis virus strains

Research (Published online: 21-08-2019)

15. Risk factors associated with viral nervous necrosis in hybrid groupers in Malaysia and the high similarity of its causative agent nervous necrosis virus to reassortant red-spotted grouper nervous necrosis virus/striped jack nervous necrosis virus strains

Nurshuhada Ariff, Azila Abdullah, Mohamed Noor Amal Azmai, Najiah Musa and Sandra Catherine Zainathan

Veterinary World, 12(8): 1273-1284

ABSTRACT

Background and Aim: Viral nervous necrosis (VNN) is a serious disease of several marine fish species. VNN causes 100% mortality in the larval stages, while lower losses have been reported in juvenile and adult fish. This study aimed to detect the occurrence of VNN while identifying its associated risk factors and the genotypes of its causative agent in a hybrid grouper hatchery in Malaysia.

Materials and Methods: A batch of newly hatched hybrid grouper fry (Epinephelus fuscoguttatus X Epinephelus lanceolatus) were followed from the larval stage to market size. Samples of the hybrid groupers, water, live feed, and artificial fish pellets were collected periodically from day 0 to 180 in the hybrid grouper hatchery. Reverse transcription-polymerase chain reaction (RT-PCR) and nested PCR amplifications were carried out on VNN-related sequences. The phylogenetic tree including the sampled causative agent of VNN was inferred from the coat protein genes from all known Betanodavirus species using Molecular Evolutionary Genetics Analysis (MEGA). Pearson's correlation coefficient values were calculated to determine the strength of the correlation between the presence of VNN in hybrid grouper samples and its associated risk factors.

Results: A total of 113 out of 146 pooled and individual samples, including hybrid grouper, water, and artificial fish pellet samples, demonstrated positive results in tests for the presence of VNN-associated viruses. The clinical signs of infection observed in the samples included darkened skin, deformation of the backbone, abdominal distension, skin lesions, and fin erosion. VNN was present throughout the life stages of the hybrid groupers, with the first detection occurring at day 10. VNN-associated risk factors included water temperature, dissolved oxygen content, salinity, ammonia level, fish size (adults more at risk than younger stages), and life stage (age). Detection of VNN-associated viruses in water samples demonstrated evidence of horizontal transmission of the disease. All the nucleotide sequences found in this study had high nucleotide identities of 88% to 100% to each other, striped jack nervous necrosis virus (SJNNV), and the reassortant strain red-spotted grouper NNV/SJNNV (RGNNV/SJNNV) isolate 430.2004 (GenBank accession number JN189932.1) (n=26). The phylogenetic analysis showed that quasispecies was present in each VNN-causing virus-positive sample, which differed based on the type of sample and life stage.

Conclusion: This study was the first to confirm the existence of a reassortant strain (RGNNV/SJNNV) in hybrid groupers from Malaysia and Southeast Asia. However, the association between the mode of transmission and the risk factors of this virus needs to be investigated further to understand the evolution and potential new host species of the reassortant strain.

Keywords: epidemiology, quasispecies, reassortant, red-spotted grouper nervous necrosis virus-striped jack nervous necrosis virus, viral nervous necrosis.

Evaluation of hepatobiliary ultrasound scores in healthy dogs and dogs with liver diseases

Research (Published online: 17-08-2019)

14. Evaluation of hepatobiliary ultrasound scores in healthy dogs and dogs with liver diseases

Sathidpak Nantasanti Assawarachan, Piyathip Chuchalermporn, Phudit Maneesaay and Naris Thengchaisri

Veterinary World, 12(8): 1266-1272

ABSTRACT

Background and Aim: Ultrasonography is the first-line method for examining the canine liver. Hepatic ultrasound scoring systems are widely described in human medicine, yet there is no information on the use of semi-quantitative ultrasound scoring systems in canine liver diseases. This study aimed to evaluate the hepatobiliary ultrasound scores between physically healthy dogs and dogs with primary liver diseases confirmed by clinical, biochemical, and histological parameters. We also evaluated the putative correlations between ultrasound scores and ALT or ALP levels. Moreover, the severity of ultrasound scoring and fold changes in liver enzymes was also evaluated.

Materials and Methods: A cross-sectional study design was conducted to compare the results of the six different parameters (liver surface, echogenicity of parenchyma, nodularity of parenchyma, gallbladder wall thickness, amount of gall sludge, and visibility of bile duct) of ultrasound scores between dogs with and without liver disease.

Results: Our results showed that 17.4%, 88.2%, and 100% of dogs with liver diseases were identified according to the ultrasound severity classified as mild (total score 0-2), moderate (total score 3-5), and severe (total score 6-12). Approximately 30% of patients with chronic hepatitis, the most common canine liver disease, presented with normal or mild ultrasound score category, whereas most of the patients with vacuolar hepatopathy and steroid-induced hepatopathy due to secondary reactive changes had moderate-to-severe ultrasound score category. There were 75% of patients with tumor and 80% of patients with hepatic fibrosis that were identified with severe ultrasound score category. Dogs with moderate-to-severe ultrasound scores had significant liver enzyme elevation (both alanine aminotransferase [ALT] and alkaline phosphatase [ALP]) compared to those of dogs with mild ultrasound scores. Ultrasound score was moderately associated with ALT and highly associated with ALP levels (p=0.553 and p=0.730, respectively).

Conclusion: Our semi-quantitative, simplified ultrasonographic scoring system may have potential to be used as a screening tool to detect some groups of liver diseases.

Keywords: diagnosis, dogs, hepatic disease, ultrasound score.