Physiological characteristics and virulence gene composition of selected serovars of seafood-borne Salmonella enterica

http://www.veterinaryworld.org/Vol.16/March-2023/2.html

Abstract

Background and Aim: All serotypes of Salmonella enterica are considered potentially pathogenic. However, the non-typhoidal Salmonella (NTS) serotypes vary considerably in terms of pathogenicity and the severity of infections. Although diverse serotypes of NTS have been reported from tropical seafood, their sources, physiological characteristics, and virulence potentials are not well understood. This study aimed to compare the physiological characteristics of selected serovars of Salmonella from seafood and investigate possible variations in the distribution of known genes within the pathogenicity islands.

Materials and Methods: A series of biochemical tests, including carbohydrate fermentation and amino acid decarboxylation tests were performed to physiologically compare the isolates. The genetic characterization with respect to putative virulence genes was done by screening for genes associated with Salmonella pathogenicity island (SPI) I– V, as well as the toxin- and prophage-associated genes by polymerase chain reaction.

Results: Irrespective of serotypes, all the isolates uniformly harbored the five SPIs screened in this study. However, some virulence genes, such as the avrA, sodC, and gogB were not detected in all Salmonella isolates. The biochemical profiles of Salmonella serotypes were highly conserved except for variations in inositol fermentation and citrate utilization. All the isolates of this study were weak biofilm formers on polystyrene surfaces.

Conclusion: The pathogenicity profiles of environmental NTS isolates observed in this study suggest that they possess the virulence machinery necessary to cause human infections and therefore, urgent measures to contain Salmonella contamination of seafood are required to ensure the safety of consumers.

Keywords: biofilm, invasion, non-typhoidal Salmonella, Salmonella pathogenicity islands, seafood, virulence.

Effect of waste mango silage on the in vitro gas production, in situ digestibility, intake, apparent digestibility, and ruminal characteristics in calf diets

 

ABSTRACT

Background and Aim: Mexico is the fifth largest producer of mangoes in the world. For the conservation of agro-industrial waste and crop residues, the ensiling technique has shown good results. This study aimed to evaluate the effect of increasing the level of mango silage (86% waste mango and 14% pangola grass hay) in calf diets on in vitro gas production, in situ digestibility, intake, apparent digestibility, and ruminal characteristics.

Materials and Methods: The diets contained 0 (T0), 30 (T1), 45 (T2), and 60% (T3) mango silage. The partial (24, 48, and 72 h) and cumulative (72 h) biogas, CH4 production, and degradation were determined in the in vitro evaluation. In situ digestibility and estimators of fermentation kinetics of dry matter (DM) and organic matter (OM) were determined. Intake, apparent nutrient digestibility, and rumen parameters of calves (200 kg) were evaluated in a 4 × 4 Latin square design. Response to increased mango silage was calculated by linear and quadratic orthogonal contrasts.

Results: In vitro partial and cumulative biogas production decreased linearly (p < 0.05), and the partial and cumulative CH4 production did not show linear or quadratic contrast (p > 0.05); in vitro DM degradation, in vitro neutral detergent fiber degradation, and in vitro acid detergent fiber degradation showed a linear increase (p < 0.05). In situ dry matter digestibility (DMDis), in situ organic matter digestibility (OMDis), b, a + b, c, and effective digestibility (ED) of DMDis, a, a + b, c, and ED of OMDis increased linearly (p < 0.05). Dry matter intake, OM intake, and crude protein intake showed a linear increase (p < 0.05); NDF intake and ADF intake presented a quadratic behavior (p < 0.05). Apparent digestibility of DM, OM, CP, and hemicellulose, pH, N-NH3, total bacterial count, acetate, propionate, butyrate, volatile fatty acids, acetate: propionate ratio, cellulolytic bacteria, and protozoa did not present a linear or quadratic orthogonal effect (p > 0.05).

Conclusion: The in vitro, in situ, and in vivo variables demonstrated that up to 60% mango silage can be used for the intensive fattening of calves in confinement.

Keywords: alternative feed, alternative feeding, cattle, silage, tropics.

The first study on the prevalence of gastrointestinal parasites in owned and sheltered cats in Yangon, Myanmar

Research (Published online: 28-02-2023)

21. The first study on the prevalence of gastrointestinal parasites in owned and sheltered cats in Yangon, Myanmar

Babi Kyi Soe, Khin Su Hlaing, Toe Win Naing, Zin Hnin Thaw, and Win Myint

Veterinary World, 16(2): 414-420

ABSTRACT

Background and Aim: People who used to rear companion animals are healthier than others who do not. Gastrointestinal (GI) helminths are common in cats and serve as reservoirs for zoonotic diseases. However, the prevalence of GI parasites in cats in Myanmar has never been reported. This study aimed to estimate the prevalence of GI parasites in cats in Myanmar and identify the potential risk factors associated with GI parasites.

Materials and Methods: A total of 230 fecal samples were collected from seven veterinary clinics and two shelters within the Yangon region from January to May 2022. Sampled cats were classified according to age, gender, and deworming and rearing practices. Fecal samples were analyzed by fecal wet mount, ethyl acetate centrifugal sedimentation, and zinc sulfate centrifugal flotation techniques. Descriptive data were described, and Pearson's χ2 test was used to identify associated risk factors, such as age, gender, and deworming and rearing practices.

Results: The overall prevalence of GI parasites was 79.56%, and 57.82% of cats were infected with a diagnostic stage of more than one parasite species. Seven GI parasites were detected, including Ancylostoma spp. (55.65%), Toxocara spp. (46.08%), Trichuris spp. (20.86%), Platynosomum spp. (11.73%), Dipylidium caninum (7.39%), Taenia spp. (4.34%), and Cystoisospora spp. (32.17%). Based on statistical analysis, deworming and rearing practices were significantly associated (p < 0.05) with GI parasitic infections.

Conclusion: This study is the first to reveal the prevalence of GI parasites that could assist the need for effective control measures for zoonotic hookworm and roundworm infections in cats. Even with simple microscopic examination, the remarkably high prevalence of GI parasitic infections warrants regular deworming practice. Further molecular studies should also be performed to understand their genetic diversity.

Keywords: cat, gastrointestinal parasites, Myanmar, prevalence.

Prevalence, antibiotic resistance patterns, and biofilm formation ability of Enterobacterales recovered from food of animal origin in Egypt

Research (Published online: 28-02-2023)

20. Prevalence, antibiotic resistance patterns, and biofilm formation ability of Enterobacterales recovered from food of animal origin in Egypt

Shimaa N. Edris, Ahmed Hamad, Dina A. B. Awad, and Islam I. Sabeq

Veterinary World, 16(2): 403-413

ABSTRACT

Background and Aim: The majority of animal-derived food safety studies have focused on foodborne zoonotic agents; however, members of the opportunistic Enterobacteriaceae (Ops) family are increasingly implicated in foodborne and public health crises due to their robust evolution of acquiring antimicrobial resistance and biofilms, consequently require thorough characterization, particularly in the Egyptian food sector. Therefore, this study aimed to determine the distribution and prevalence of Enterobacteriaceae family members in animal-derived foods, as well as their resistance to important antimicrobials and biofilm-forming potential.

Materials and Methods: A total of 274 beef, rabbit meat, chicken meat, egg, butter, and milk samples were investigated for the presence of Enterobacteriaceae. All isolated strains were first recognized using traditional microbiological techniques. Following that, matrix-assisted laser desorption ionization-time of flight mass spectrometry was used to validate the Enterobacteriaceae's identity. The isolated enterobacteria strains were tested on disk diffusion and crystal violet quantitative microtiter plates to determine their antibiotic resistance and capacity to form biofilms.

Results: There have been thirty isolates of Enterobacteriaceae from seven different species and four genera. Out of the three food types, Pseudomonas aeruginosa had the highest prevalence rate (4.1%). With three species, Enterobacter genera had the second-highest prevalence (3.28%) across five different food categories. In four different food types, the Klebsiella genera had the second-highest distribution and third-highest incidence (2.55%). Almost all isolates, except three Proteus mirabilis, showed prominent levels of resistance, particularly to beta-lactam antibiotics. Except for two Enterobacter cloacae and three P. mirabilis isolates, all isolates were classified as multidrug-resistant (MDR) or extensively multidrug-resistant (XDR). The multiple antibiotic resistance index (MARI) of the majority of isolates dropped between 0.273 and 0.727. The highest MARI was conferred by Klebsiella pneumoniae, at 0.727. Overall, 83.33% of the isolates had strong biofilm capacity, while only 16.67% exhibited moderate capacity.

Conclusion: The MDR, XDR, and strong biofilm indicators confirmed in 83.33% of the currently tested Enterobacteriaceae from animal-derived foods suggest that, if not addressed, there may be rising risks to Egypt's economy and public health.

Keywords: biofilm, Enterobacteriaceae, food safety, multidrug resistance.

Lactic acid bacteria and yeast strains isolated from fermented fish (Budu) identified as candidate ruminant probiotics based on in vitro rumen fermentation characteristics

Research (Published online: 28-02-2023)

19. Lactic acid bacteria and yeast strains isolated from fermented fish (Budu) identified as candidate ruminant probiotics based on in vitro rumen fermentation characteristics

Laily Rinda Ardani, Yetti Marlida, Mardiati Zain, Jamsari Jamsari, and Dilla Mareistia Fassah

Veterinary World, 16(2): 395-402

ABSTRACT

Background and Aim: Probiotic supplementation can assist with manipulating the rumen microbial ecosystem. Lactic acid bacteria and yeast from fermented fish (Budu) as the indigenous food from West Sumatra, Indonesia, are potential probiotics for livestock. This study aims to select the best candidate lactic acid bacteria and yeast strains from fermented fish as ruminant probiotics and evaluate the effect of their supplementation on the characteristics of rumen fermentation, feed digestion, and total gas production in vitro.

Materials and Methods: This study used nine treatments, performed in triplicate, in a completely randomized design. The substrate ratio comprised of 70% Pennisetum purpureum forage and 30% concentrate. Five lactic acid bacteria and three yeast isolates were used in this study. Treatments were as follows: T0: control (basal diet); T1: T0 + Lactobacillus parabuchneri strain 3347; T2: T0 + Lactobacillus buchneri strain 5296; T3: T0 + Lactobacillus harbinensis JCM 16178; T4: T0 + Schleiferilactobacillus harbinensis strain LH991; T5: T0 + L. parabuchneri strain 6902; T6: T0 + Pichia kudriavzevii strain B-5P; T7: T0 + P. kudriavzevii strain CBS 5147; and T8: T0 + commercial yeast (Saccharomyces cerevisiae). The lactic acid bacteria inoculum contained 1.02 × 1011 colony-forming unit (CFU)/mL, while the yeast inoculum contained 1.5 × 1010 CFU/mL.

Results: The results showed that four lactic acid bacteria and three yeast produced a higher total gas yield (104–183.33 mL) compared to the control (103 mL). Supplementation with lactic acid bacteria in the rumen fermentation in vitro showed dry matter digestibility of 63%–70% and organic matter digestibility (OMD) of 64%–71%. We observed that total volatile fatty acid (VFA) production in all treatments was significantly higher (86–121 mM) compared to the control (81 mM). The concentration of NH3 production was higher in all treatments (12.33–16.83 mM) than in the control (12.25 mM). Meanwhile, the probiotic supplementation did not cause a significant change in the rumen pH (6.86–7.12). Supplementation with the lactic acid bacteria S. harbinensis strain LH991 consistently demonstrated the best results from the parameters of dry and OMD (70.29% and 71.16%, respectively), total VFA (121.67 mM), NH3 (16.83 mM), and total gas production (149.17 mL). The best results were observed from the yeast candidate P. kudriavzevii strain B-5P, where the results were dry and OMD (67.64% and 69.55% respectively), total VFA (96.67 mM), NH3 (13.42 mM), and total gas production (183.33 mL).

Conclusion: Based on the obtained results, lactic acid bacteria S. harbinensis strain LH991 and yeast P. kudriavzevii strain B-5P are attractive candidates to be utilized as probiotics for ruminants based on their potential to improve rumen fermentation in vitro. This probiotic supplementation can increase the digestibility of feed ingredients, production of total VFA and NH3, and total gas produced.

Keywords: in vitro, lactic acid bacteria, probiotics, rumen fermentation, yeast.

Comparison of the efficacy and perioperative pain between vessel sealing and suture ligation for median celiotomy in canine ovariohysterectomy

Research (Published online: 28-02-2023)

18. Comparison of the efficacy and perioperative pain between vessel sealing and suture ligation for median celiotomy in canine ovariohysterectomy

Jutapoln Sunghan, Sareepah Manmoo, Wanna Suriyasathaporn, Witaya Suriyasathaporn, Kanawee Warrit, and Pradipa Kusolphat

Veterinary World, 16(2): 386-394

ABSTRACT

Background and Aim: Vessel sealing (VS) is used widely in human medicine and veterinary practice during laparoscopic surgery; however, few studies have investigated VS in canine ovariohysterectomy (OHE) using the median celiotomy approach. This study aimed to compare the effect of VS and suture ligation (SL) on surgical time, blood loss, and perioperative pain in canine OHE through median celiotomy.

Materials and Methods: Twenty-eight dogs were randomly and equally assigned into two groups that underwent surgery either by SL at both the ovarian pedicle and uterus or using a disposable VS device. The short form of the Glasgow composite pain scale (SF-GCPS) and the Colorado state university canine acute pain scale (CSU-CAP) were used to determine pain pre-operatively (baseline); at 30 min; and at 1, 2, 3, 4, 24, and 72 h post-operatively. Perioperative physiological parameters, surgical duration, and percentage of blood loss were recorded. Repeated measures analysis was performed to determine the differences in all parameters among time-related tasks and between both groups. A significant difference was defined at p < 0.05.

Results: The duration from identification of the first ovary to uterus removal was shorter in VS than in SL (p < 0.05). No clinically relevant differences were found among physiological variables. Both groups showed higher SF-GCPS and CSU-CAP values after surgery compared with baseline. The SF-GCPS in SL at 1 h was higher than in VS (p < 0.05). Two dogs in the SL group required additional post-operative rescue analgesia. No differences were found between the groups in terms of blood loss.

Conclusion: The use of a VS device in dogs undergoing OHE celiotomy decreased post-operative pain and shortened the perioperative time, making it an effective alternative technique for this common surgery. However, the VS device must be applied 2–3 times in the same location during the OHE procedure to prevent technical failure. This disposable device was reused up to 5 times for economic reasons without device failure. Soft tissue damage during OHE using the VS device should be investigated in a future prospective study.

Keywords: ligation, ovariohysterectomy, post-operative pain, vessel sealing.

Potential protective effects of red grape seed extract in a rat model of malathion-induced neurotoxicity

Research (Published online: 26-02-2023)

17. Potential protective effects of red grape seed extract in a rat model of malathion-induced neurotoxicity

Mohamed Jamal Saadh

Veterinary World, 16(2): 380-385

ABSTRACT

Background and Aim: Exposure to pesticide mixtures used in agricultural practice poses a grave risk to non-target animals. This study aimed to determine whether red grape seed extract (RGSE, which is 95% bioflavonoids and equal to 12,000 mg of fresh red grape seed, and 150 mg of vitamin C) alleviated the changes in brain-derived neurotrophic factor (BDNF) level, acetylcholinesterase activity, oxidative stress, and apoptosis induced by orally administered malathion in a rat model of malathion-induced neurotoxicity.

Materials and Methods: Thirty-two adult male Wistar albino rats were divided into four groups and exposed to malathion with or without 4 weeks of RGSE treatment, treated with RGSE alone, or left untreated as controls. The animals were euthanized 24 h after last treatment. Brain samples were collected to measure acetylcholinesterase, superoxide dismutase (SOD), and caspase 3 activity, total antioxidant capacity (TAC), and BDNF levels.

Results: Malathion significantly reduced acetylcholinesterase and SOD activity and TAC and significantly increased caspase 3 activity. In comparison, acetylcholinesterase and SOC activity, BDNF level, and TAC were improved and caspase 3 activity was decreased in the malathion-RGSE group, indicating that RGSE corrected the alterations detected in these biochemical parameters.

Conclusion: Oxidative stress and apoptosis in the brains of rats exposed to oral malathion were substantially controlled by RGSE treatment.

Keywords: apoptosis, malathion toxicity, oxidative stress, pesticide, red grape seed extract.