Cellular immune response of Staphylococcus aureus enterotoxin B in Balb/c mice through intranasal infection

Research (Published online: 24-07-2022)

22. Cellular immune response of Staphylococcus aureus enterotoxin B in Balb/c mice through intranasal infection

Hidayatun Nisa Purwanasari, Amanda Tri Utami Permatasari, Fajar Budi Lestari, Madarina Wasissa, Khusnan Zaini and Siti Isrina Oktavia Salasia

Veterinary World, 15(7): 1765-1771

ABSTRACT

Background and Aim: Staphylococcus aureus produces various superantigen exotoxins, including staphylococcal enterotoxin B (SEB). It causes fatal anaphylactic reactions and toxic shock. This study aimed to evaluate the reaction of leukocytes and histopathological changes in the respiratory organs of Balb/c mice after intranasal infection with enterotoxigenic S. aureus (SEB).

Materials and Methods: The presence of the seb gene in S. aureus was established in this study using polymerase chain reaction-specific primer. Two groups of 8-week-old male Balb-c mice consist of six mice in each group. The treated group was infected with 50 μL and 100 μL of SEB intranasal on days 1 and 14, respectively. NaCl was administered in the second group and was considered as a control group. Blood samples were collected through the retro-orbital plexus on days 1, 4, 7, 14, and 22 after infections. Total cell counts were analyzed with an independent sample t-test and compared using the statistical package for the social sciences (SPSS) version 16.0 (IBM Corp., NY, USA). The infected tissues of the respiratory organ were observed descriptively and compared to the control group.

Results: The seb gene with a molecular size of 478 bp, indicating the SEB strain, is present in S. aureus used in this study. Intranasal administration of SEB showed increased leukocytes, lymphocytes, monocytes, and eosinophils on day 22 post-infection. Significant leukocytosis was seen on days 6 and 14; lymphocytosis on days 1, 4, 6, and 16; and eosinophilia on days 6, 14, and 22 compared with the control group (p > 0.05). In contrast, the neutrophil decreased after an increase of immature band cells compared to the control group, indicating a severe acute infection with SEB. The lungs and trachea of the test group had an inflammatory cell accumulation in the respiratory organ.

Conclusion: Intranasal route infection of S. aureus containing seb gene significantly induced the cellular immune response and caused pathological changes in the respiratory tissues of the Balb/c mice model. The hematological changes were aligned with marked pathological changes in the respiratory tract. Balb/c mice could be an excellent experimental model to study toxic and anaphylactic shock against SEB to define the future therapeutic agents.

Keywords: enterotoxin B, hematology, histopathology, intranasal, Staphylococcus aureus.

Aerolysin gene characterization and antimicrobial resistance profile of Aeromonas hydrophila isolated from milkfish (Chanos chanos) in Gresik, Indonesia

Research (Published online: 23-07-2022)

21. Aerolysin gene characterization and antimicrobial resistance profile of Aeromonas hydrophila isolated from milkfish (Chanos chanos) in Gresik, Indonesia

Faisal Fikri, Dhandy Koesoemo Wardhana, Agus Purnomo, Shafia Khairani, Shekhar Chhetri and Muhammad Thohawi Elziyad Purnama

Veterinary World, 15(7): 1759-1764

ABSTRACT

Background and Aim: Motile Aeromonas septicemia is a crucial disease in freshwater fish. Aeromonas hydrophila is a disease agent associated with sporadic fish mortality, food safety, and public health. This study aimed to estimate the prevalence and the presence of the aerolysin gene and antimicrobial resistance profile of A. hydrophila isolated from milkfish in Gresik, Indonesia.

Materials and Methods: A total of 153 milkfish gill samples were collected from 16 locations in Gresik and then cultured and identified using biochemical tests. The aerolysin gene was investigated using a polymerase chain reaction, and antimicrobial resistance profiles of the recovered isolates were investigated.

Results: Of the 153 examined samples, 35 (22.9%) were confirmed positive for A. hydrophila and 22 (62.9%) presented the aerolysin gene. The recovered isolates were resistant to the following antibiotics: Amoxicillin (62.9%), tetracycline (60%), streptomycin (54.3%), cefotaxime (51.4%), gentamycin (31.4%), kanamycin (28.6%), erythromycin (25.7%), chloramphenicol (20%), and trimethoprim (14.3%). Meanwhile, only ciprofloxacin, nalidixic acid, and imipenem were indicated as susceptible.

Conclusion: The presence of the aerolysin gene is vital in determining the virulence of A. hydrophila. The study results indicated a high aerolysin gene prevalence. In addition, this study emphasized antibiotic use monitoring, food safety improvement, and negative impact reduction on human health and the environment.

Keywords: aerolysin gene, Aeromonas hydrophila, antimicrobial resistance, milkfish, public health.

Bio-efficacy of Mangifera leaf extracts on mortality of Aedes aegypti and inhibition of egg hatching

Research (Published online: 23-07-2022)

20. Bio-efficacy of Mangifera leaf extracts on mortality of Aedes aegypti and inhibition of egg hatching

Nur Mahdi, Muhammad Rasyid Ridha, Deni Setiawan, Muhammad Riki Shindi Praristiya, Nita Rahayu and Bayu Purnama Atmaja

Veterinary World, 15(7): 1753-1758

ABSTRACT

Background and Aim: To develop an environmentally friendly alternative to mosquito larvicides for vegetables, leaf extracts of Mangifera laurina, Mangifera casturi, Mangifera indica, Mangifera odorata, Mangifera caesia, and Mangifera foetida were prepared. This study aimed to determine the biological efficacy of several Mangifera leaf extracts on the mortality of Aedes aegypti mosquito and the inhibition of egg hatching.

Materials and Methods: Extraction was performed in an organic solvent (methanol) using a Soxhlet extractor. The larvicidal potential of six leaves of Mangifera essential oil was evaluated against the third instar larvae of A. aegypti at concentrations of 1500, 2000, 3000, and 5000 ppm using the World Health Organization protocol. After Probit analysis, the 48 h LC50 and LC90 values of the essential oils were determined. The inhibitory effect on egg hatching was also tested at 160, 320, 480, and 640 ppm.

Results: The extraction of essential oils from several Mangifera species had excellent larvicidal activity and inhibitory activity against A. aegypti egg hatching. The LC50/LC90 values were: M. casturi, 241/1964 ppm; M. laurina, 2739/4035 ppm; and M. caesia, 1831/2618 ppm. The inhibitory effect on hatching was 78% for M. foetida, 70% for M. caesia, and 59% for M. casturi.

Conclusion: The test results indicate the potential of some Mangifera species for use as larvicides and inhibitors of egg hatching; thus, they have the potential to control A. aegypti in the early stages of development.

Keywords: Aedes aegypti, bio-efficacy, leaf extracts, Mangifera.

Silver nanoparticle-conjugated antibiotics inhibit in vitro growth of Brucella melitensis

Research (Published online: 22-07-2022)

19. Silver nanoparticle-conjugated antibiotics inhibit in vitro growth of Brucella melitensis

Mohamed J. Saadh

Veterinary World, 15(7): 1749-1752

ABSTRACT

Background and Aim: Brucellosis is a contagious livestock disease with a significant economic impact. This study aimed to compare the efficacy of antibiotics used alone or in combination with silver nanoparticles (AgNPs) against Brucella melitensis Rev 1 in vitro.

Materials and Methods: AgNps conjugated with ciprofloxacin was synthesized and thoroughly characterized by ultraviolet visible spectrophotometry (UV-vis). The antimicrobial effect of ciprofloxacin alone and ciprofloxacin conjugated with AgNPs against B. melitensis Rev 1 was determined by minimum inhibitory concentration (MIC) and the erythrocyte hemolytic assay determined the capability of conjugation to cause hemolysis in human erythrocyte.

Results: The UV-vis spectra of both silver-drug nanoconjugates showed a characteristic surface plasmon resonance band at 420 nm. The MIC assays showed that AgNPs conjugation to antibiotics enhanced the antibacterial potential of the selected antibiotics against B. melitensis Rev 1 relative to non-conjugated antibiotics. The results show that low concentrations of AgNPs can kill B. melitensis Rev 1. The MICs of ciprofloxacin and ciprofloxacin–AgNPs were 0.75 and 0.05 μM, respectively.

Conclusion: The conjugation of ciprofloxacin with AgNPs enhanced the antibacterial effects against B. melitensis Rev 1. In addition, this conjugation appears to inhibit the capability of this bacterium to adapt to the presence of antibiotics, thereby inhibiting bacterial resistance. Further studies are required to examine its potential as an in vivo treatment.

Keywords: antimicrobial activity, Brucella melitensis Rev 1, minimum inhibitory concentrations, silver nanoparticles.

Effect of housefly (Musca domestica) larvae on the growth performance and carcass characteristics of local chickens in Niger

Research (Published online: 22-07-2022)

18. Effect of housefly (Musca domestica) larvae on the growth performance and carcass characteristics of local chickens in Niger

Bachir Hamani, Nassim Moula, Adamou Guisso Taffa, Idriss Hamidou Leyo, Chaibou Mahamadou, Johann Detilleux and Quynh Chau Dang Van

Veterinary World, 15(7): 1738-1748

ABSTRACT

Background and Aim: The meat supply of local poultry for human consumption is greater than that of fast-growing poultry in Niger. However, meeting the protein needs of these local chickens is a major challenge due to the availability of protein sources and their cost. Nowadays, insect larvae such as houseflies are used and even recommended as animal feed; hence, the need to evaluate the effect of housefly (Musca domestica) larvae on the growth performance of local chickens. This study investigated the feeding effects of housefly larvae on the growth performance and carcass characteristics of local Nigerien chickens and determined the rate of fish meal substitution, in fresh or dry larvae form, whichever would be preferable.

Materials and Methods: A total of 165 3-week-old local unsexed chickens of the salmon variety, weighing 120.3 ± 15.43 g, were used to evaluate the effect of housefly (M. domestica) larvae on their growth performance and carcass yield (CY). The experiment consisted of five treatments with three replicates, that is, 15 batches of 11 animals each. Five iso-protein-caloric diets were developed with 25%, and then 50% fish meal substitution with fresh and dried housefly larvae. The chicks were reared together during the first 3 weeks for their adaptation, during which they were fed an imported starter commercial feed, ad libitum. After that, they were weighed weekly for 12 weeks. Next, the body weights (BWs) were taken weekly for all chicks, feed daily intake and mortality were recorded daily, and average daily gain, feed conversion ratio (FCR), and viability rate were calculated. In the end, four chickens (two males and two females) per batch were slaughtered for the CY evaluation, breast meat, drumstick and tight (legs), and wings. Statistical analyses were performed using a linear mixed model for repeated data.

Results: The weight, FCR, and carcass traits were unaffected by either the rate or larvae state. Conversely, the growth rate was improved, and feed consumption was increased. Notably, the chickens consumed more feed but grew faster with fresh larvae and at a higher substitution rate.

Conclusion: This study reported that 50% fresh or dried housefly larvae substituted into the fish meal in growing local chicken's diets had no effect on their BW, FCR, and carcass traits but increased the growth rate and feed consumption.

Keywords: alternative feeds stuff, animals feeding, carcass, indigenous chicken, insect larvae, poultry diets, zootechny.

Assessing farm biosecurity and farmers' knowledge and practices concerning antibiotics and antibiotic resistance in poultry and pig farms in Southern Togo

Research (Published online: 21-07-2022)

17. Assessing farm biosecurity and farmers' knowledge and practices concerning antibiotics and antibiotic resistance in poultry and pig farms in Southern Togo

Andre Pouwedeou Bedekelabou, Essodina Talaki, Koffi Francois-Xavier Dzogbema, Malibida Dolou, Madi Savadogo, Malik Orou Seko and Rianatou Bada Alambedji

Veterinary World, 15(7): 1727-1737

ABSTRACT

Background and Aim: Several factors contribute to the unusual incidence of antibiotic resistance, which is now a primary public health concern. However, failure in managing preventive and therapeutic antibiotic use on farms is one of the most crucial factors. Therefore, this study aimed to evaluate the biosecurity of farms, farmers' competence, and practices related to antibiotics and their resistance in poultry and pig rearing in Togo.

Materials and Methods: Through a cross-sectional survey, 121 commercial poultry farmers and 97 commercial pig farmers were questioned to evaluate the biosecurity of farms and farmers' competence and practices related to antibiotics and antibiotic resistance. Descriptive analyses, including the evaluation of proportions, were carried out. In addition, results from qualitative factors were evaluated in a defined grid and totaled up to assess cleanliness measures, awareness, and behavior regarding antibiotics and their resistance.

Results: The results demonstrated that most farmers working on poultry farms had a university education, while most working on pig farms had secondary education. Most poultry (69%) and pig (44%) farms were of small sizes (<1000 animals in poultry and <10 animals in pig farming). The footbaths were used in just 51% of poultry farms and 4% of pig farms, respectively, with 37% and 82% of poultry and pig farms having inadequate levels of hygiene. In poultry farms, respiratory issues and periodic decline in egg-laying were the main problems. Simultaneously, skin disorders (scabies) and plagues (African swine fever) were the primary health constraints in pig farming. Tetracycline is the most commonly used antibiotic by farmers. However, in poultry and pig farms, 21% and 67% of farmers were unaware of antibiotics. In addition, 39% and 57% were unaware of antibiotic resistance. Poultry and pig farmers' competence were substantially linked to their education level. Poultry farmers demonstrated better practices, including procuring antibiotics based on veterinary prescriptions (63%) and they knew where antibiotics should be bought (90%). Nevertheless, 43% of farmers asserted unpleasant activities – no application for laboratory testing (93%) and use of antibiotics for prevention (82%). In pig farming, most farmers (69%) reported inadequate incidents of the use of antibiotics.

Conclusion: This study identified a crucial non-compliance with biosecurity measures and good practices toward antibiotic use on many farms. Therefore, training of farmers is mandatory for safe livestock products.

Keywords: antibiotic resistance, antibiotics, biosecurity, knowledge, pig, poultry, practice.

Predicting body weight of Kalahari Red goats from linear body measurements using data mining algorithms

Research (Published online: 21-07-2022)

16. Predicting body weight of Kalahari Red goats from linear body measurements using data mining algorithms

Kwena Mokoena, Kagisho Madikadike Molabe, Mmakosha Cynthia Sekgota and Thobela Louis Tyasi

Veterinary World, 15(7): 1719-1726

ABSTRACT

Background and Aim: The Kalahari Red goat breed is the finest meat-producing species in South Africa, and its coat color ranges from light to dark red-brown. A practical approach to estimating their body weight (BW) using linear body measurements is still scarce. Therefore, this study aimed to determine the best data mining technique among classification and regression trees (CART), Chi-square automatic interaction detection (CHAID), and exhaustive CHAID (Ex-CHAID) for predicting the BW of Kalahari Red goats.

Materials and Methods: This study included 50 Kalahari Red goats (does = 42 and bucks = 8) aged 3–5 years. Body length (BL), heart girth (HG), rump height (RH), height at withers (WH), sex, and age were the essential indicators to estimate BW. The best model was chosen based on the goodness of fit, such as adjusted coefficient of determination (Adj. R2), coefficient of determination (R2), root mean square error (RMSE), standard deviation ratio (SD ratio), mean absolute percentage error, Akaike information criteria, relative approximation error, and coefficient of variation.

Results: The SD values of the ratio ranged from 0.32 (CART) to 0.40 (Ex-CHAID). The greatest R2 (%) was established for CART (89.23), followed by CHAID (81.99), and the lowest was established for Ex-CHAID (81.70). CART was established as the preferred algorithm with BL, HG, and WH as critical predictors. The heaviest BW (73.50 kg) was established in four goats with BL higher than 92.5 cm.

Conclusion: This study reveals that CART is the optimum model with BL, HG, and WH as the essential linear body measurements for estimating BW for Kalahari Red goats. The updated records will assist the rural farmers in making precise judgments for various objectives, such as marketing, breeding, feeding, and veterinary services in remote areas where weighing scales are unavailable.

Keywords: body length, data mining algorithms, heart girth, rump height, withers height.