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It is known that gilt progeny performance is reduced compared with sow progeny. Previous research suggests that the presence of maternal feces in early life improves the health and survival of offspring. Therefore, we aimed to determine whether contact with feces from multiparous (MP) sows would improve the growth and survival of piglets born and reared on primiparous (P1) sows and if so, whether these differences are associated with the gut microbiota. Four treatments were applied for 10 days: Donor (n = 29) piglets had limited access to maternal feces as, each morning, sow feces were removed and placed in the crate of a P1 sow (P1-FT; n = 30 piglets) and P1-Con (n = 29) and MP-Con (n = 33) piglets had access to their own mothers’ feces. All piglets were weighed on days 1, 3, 10, and 18. Fecal samples were collected from a subset of sows (n = 10/treatment) 3 days post farrow and from two female piglets/litter on days 10 and 18 (n = 20/treatment) and subject to 16S rRNA amplicon analysis. Escherichia, Clostridium, Campylobacter, and Treponema were more abundant in MP sows, while P1 sows had a higher abundance of Lactobacillus and Prevotella. At 10 days, P1 progeny fecal microbiota differed, and growth and survival were reduced when compared with MP progeny. No treatment effect was observed for P1-FT piglets (P > 0.05). Donor piglets had a different fecal microbiota and improved weight and survival then all other treatments (P < 0.05). Overall, the removal of sow feces from the farrowing crate improved piglet microbiota development, growth, and survival.

Initial enteric microbial colonisation influences animal health and disease, hence an understanding of the first microbial colonisers within the piglet is important. The spiral colon of piglets that were stillborn (n = 20), born-alive (n = 10), and born alive and had sucked (n = 9) were collected from 28 sows to investigate whether initial microbial colonisation occurs pre- or post-partum and how it develops during the first 24 h post-partum. To examine this, DNA was extracted and 16S rRNA amplicon analysis was performed to allow analysis of microbial communities. The results indicate that microbial colonisation of the spiral colon had occurred in stillborn pigs, suggesting microbial exposure prior to birth. Alpha diversity metrics indicated that the number of taxa and community richness were higher in piglets that sucked (p < 0.001) and community evenness was lower in stillborns in comparison to born-alive (p < 0.001) but was not affected by colostrum consumption (p < 0.001). Additionally, when compared with stillborn piglets, the bacteria colonising the spiral colon during the first 24 h post-partum included the potentially pathogenic bacteria Escherichia coli, Clostridium perfringens and Clostridium celatum, and potentially beneficial bacteria Lactobacillus reutueri and Faecalibacterium prausnitzii. The relative presence of Archaea was high in stillborn piglets but decreased with post-natal environmental exposure. It is evident that stillborn piglets have bacteria present within their spiral colon, however further studies are needed in order to determine the time at which colonisation is initiated and the mechanisms determining how colonisation occurs. Additionally, as expected, the immediate post-natal environment largely influences the microorganisms colonising, while colostrum consumption further contributes to the microbial community enrichment.

Hastuti SD, Barton MD, Pyecroft SB, Costabile M. 2020. Assay optimization for measuring the alternate complement pathway activity in Asian seabass (Lates calcarifer). Biodiversitas 21: 3034-3040. Complement proteins are one component of innate immunity present in fish. The measurement of complement activity in fish can be used to monitor the health status of fish. This is particularly important in Asian seabass (Lates calcarifer) aquaculture, where disease can impact on productivity. We have found an optimal condition assay for measuring the alternate complement pathway (ACP) activity of Asian seabass which includes Magnesium chloride (MgCl2) concentration, buffer pH, incubation temperature and incubation time. The assay was optimized using pooled serum of Asian seabass, diluted in Magnesium ethylenediamine tetraacetic acid gelatine veronal buffer (Mg-EDTA-GVB) and added with Rabbit red blood cells (RRBC) suspension. Subsequently, the suspension was incubated and centrifuged. The supernatant was removed and transferred to a well plate and the optical density (OD) was measured at 540 nm. The optimal condition obtained included a 7.5 mM MgCl2, pH optimum of 7.5, 25°C incubation temperature, and a 30 minutes incubation period. The presently developed assay was robust, rapid, and reliable to be used in monitoring the health status of Asian seabass in aquaculture farms. It can be used as guidance in further immunological studies on this fish.

Controlled synthesis of hollow polymeric nanocapsules has attracted significant attention in a wide range of applications. This paper reports a facile method for the synthesis of hybrid starch nanocapsules decorated with silver nanoparticles using the inverse miniemulsion polyaddition technique. Silver nanoparticles are formed and embedded in the shell of the nanocapsules during the polyaddition process without using any additional reducing agents. We found that silver also acts as a lipophobe that builds up osmotic pressure in the droplets facilitating the formation of stable round shaped nanocapsules. The nanocapsules' shell thickness could be tuned from 13 to 29 nm by varying the amount of cross-linker. We investigated the minimum inhibitory concentration (MIC) of the nanocapsules against Staphylococcus epidermidis ATCC 35984 and Escherichia coli ATCC 25922 which are two bacteria of medical relevance. The silver nanoparticle decorated nanocapsules showed antibacterial properties against both bacteria at the MIC of 2.315 mu g mL(-1) while control nanocapsules without silver had no antibacterial activity. Refereed/Peer-reviewed

Globally, gulls have been associated with carriage of high levels of Escherichia coli strains resistant to critically important antimicrobials (CIAs), a major concern, as these antimicrobials are the sole alternative or one among only a few alternatives available to treat severe life-threatening infections in humans. Previous studies of Australian silver gulls demonstrated high levels of resistance to CIAs, particularly fluoroquinolone and extended-spectrum cephalosporins, among E. coli strains (carriage at 24% and 22%, respectively). This study aimed to identify and characterize strains from four distinct bird species inhabiting a common coastal environment, determine the frequency of carriage of CIA-resistant E. coli strains, and examine if these resistant clones and their resistance-encoding mobile genetic elements (MGEs) could be transmitted between species. CIA-resistant E. coli was detected in silver gulls (53%), little penguins (11%), and feral pigeons (10%), but not in bridled terns. In total, 37 different sequence types (STs) were identified, including clinically significant human-associated lineages, such as ST131, ST95, ST648, ST69, ST540, ST93, ST450, and ST10. Five main mobile genetic elements associated with blaCTX-M-positive E. coli strains isolated from three bird species were detected. Examination of clonal lineages and MGEs provided indirect evidence of transfer of resistance between bird species. The carriage of CIA-resistant E. coli by gulls and pigeons with proximity to humans, and in some instances food-producing animals, increases the likelihood of further bidirectional dissemination. IMPORTANCE It has been shown that 20% of Australian silver gulls carry drug-resistant Escherichia coli strains of anthropogenic origin associated with severe diseases, such as sepsis and urinary tract infections, in humans. To further characterize the dynamics of drug-resistant E. coli in wildlife populations, we investigated the carriage of critically important antimicrobial (CIA) drug-resistant E. coli in four bird species in a common environment. Our results indicated that gulls, pigeons, and penguins carried drug-resistant E. coli strains, and analysis of mobile genetic elements associated with resistance genes indicated interspecies resistance transfer. Terns, representing a bird species that forages on natural food sources at sea and distant from humans, did not test positive for drug-resistant E. coli. This study demonstrates carriage of CIA-resistant bacteria in multiple bird species living in areas commonly inhabited by humans and provides further evidence for a leapfrog effect of resistance in wildlife, facilitated by feeding habits.

Objectives Antimicrobial resistance (AMR) to critically important antimicrobials (CIAs) amongst Gram-negative bacteria can feasibly be transferred amongst wildlife, humans and domestic animals. This study investigated the ecology, epidemiology and origins of CIA-resistant Escherichia coli carried by Australian silver gulls (Chroicocephalus novaehollandiae), a gregarious avian wildlife species that is a common inhabitant of coastal areas with high levels of human contact. Methods Sampling locations were widely dispersed around the perimeter of the Australian continent, with sites separated by up to 3500 km. WGS was used to study the diversity and molecular characteristics of resistant isolates to ascertain their epidemiological origin. Results Investigation of 562 faecal samples revealed widespread occurrence of extended-spectrum cephalosporin-resistant (21.7%) and fluoroquinolone-resistant (23.8%) E. coli. Genome sequencing revealed that CIA-resistant E. coli isolates (n = 284) from gulls predominantly belonged to human-associated extra-intestinal pathogenic E. coli (ExPEC) clones, including ST131 (17%), ST10 (8%), ST1193 (6%), ST69 (5%) and ST38 (4%). Genomic analysis revealed that gulls carry pandemic ExPEC-ST131 clades (O25:H4 H30-R and H30-Rx) and globally emerging fluoroquinolone-resistant ST1193 identified among humans worldwide. Comparative analysis revealed that ST131 and ST1193 isolates from gulls overlapped extensively with human clinical isolates from Australia and overseas. The present study also detected single isolates of carbapenem-resistant E. coli (ST410-blaOXA-48) and colistin-resistant E. coli (ST345-mcr-1). Conclusions The carriage of diverse CIA-resistant E. coli clones that strongly resemble pathogenic clones from humans suggests that gulls can act as ecological sponges indiscriminately accumulating and disseminating CIA-resistant bacteria over vast distances.

The dominant indigenous microbes, such as lactic acid bacteria group, mainly determine the quality of naturally fermented milk products. Yeasts have also contributed to the fermentation development, especially in determining the organoleptic or physicochemical characteristics of the products. This study was aimed to evaluate the diversity of yeasts in the naturally fermented milk products from Indonesia, which were dadih and dangke by using PCR-RFLP of ITS region. Two dadih samples used with one sample were collected in three consecutive days. Dangke samples consisted of three made from buffalo milk (sample A-C), and sample D was from cow’s milk. The isolated yeasts were further characterized genotypically using RFLP analysis of the ITS region. The representative isolates of each cluster as a result of the restriction pattern obtained with HinfI and HaeIII enzymes were further identified. A total of 37 yeast isolates (17 isolates from dadih and 22 isolates from dangke) were grouped into three clusters based on the band pattern of RFLP analysis. Based on DNA sequencing analysis, the three species were identified as Saccharomyces cerevisiae (group I), Candida metapsilosis (group II) and Kluyveromyces marxianus (group III). Saccharomyces cerevisiae and Kluyveromyces marxianus were found in both dadih and dangke samples. Unfortunately, yeasts were not detected in dangke samples A and C. Candida metapsilosis was found frequently in dadih, while Saccharomyces cerevisiae was the dominant species in dangke. Further investigations are needed to shed light on microbial dynamics since the changes in the abundance and type of microbiota during the fermentation process play a pivotal role in the quality of the final products.

Naturally, fermented milk has become an essential commodity in rural areas in some developing countries, especially in Africa and Asia. A variety of local products appear depending on local knowledge, including the type of milk, containers, and techniques. Although the microbial composition of each product varies, lactic acid bacteria commonly dominate the range of naturally fermented milk products. Research into functional benefits for human health about the role of their microflora is rapidly expanding. The role of lactic acid bacteria as probiotics for either prevention or treatment of human diseases has been a driving force in the exploration of new potential probiotics from naturally fermented milk. Inflammatory intestinal diseases are one of the digestive problems caused by dysbiosis. Therefore, the contribution of probiotics to improve the balance and diversity of intestinal microbiota has become a main concern. The main focus of this review was to summarize a variety of naturally fermented milk products by highlighting the production process and indigenous microflora involved. The determination of probiotics that are highly involved in the fermentation of milk may have health benefits for treating inflammatory intestinal diseases, especially inflammatory bowel disease and intestinal mucositis Refereed/Peer-reviewed

Background Antibiotic misuse in food-producing animals is potentially associated with human acquisition of multidrug-resistant (MDR; resistance to ≥ 3 drug classes) bacteria via the food chain. We aimed to determine if MDR Gram-negative (GNB) organisms are present in fresh Australian chicken and pork products. Methods We sampled raw, chicken drumsticks (CD) and pork ribs (PR) from 30 local supermarkets/butchers across Melbourne on two occasions. Specimens were sub-cultured onto selective media for third-generation cephalosporin-resistant (3GCR) GNBs, with species identification and antibiotic susceptibility determined for all unique colonies. Isolates were assessed by PCR for SHV, TEM, CTX-M, AmpC and carbapenemase genes (encoding IMP, VIM, KPC, OXA-48, NDM). Results From 120 specimens (60 CD, 60 PR), 112 (93%) grew a 3GCR-GNB (n = 164 isolates; 86 CD, 78 PR); common species were Acinetobacter baumannii (37%), Pseudomonas aeruginosa (13%) and Serratia fonticola (12%), but only one E. coli isolate. Fifty-nine (36%) had evidence of 3GCR alone, 93/163 (57%) displayed 3GCR plus resistance to one additional antibiotic class, and 9/163 (6%) were 3GCR plus resistance to two additional classes. Of 158 DNA specimens, all were negative for ESBL/carbapenemase genes, except 23 (15%) which were positive for AmpC, with 22/23 considered to be inherently chromosomal, but the sole E. coli isolate contained a plasmid-mediated CMY-2 AmpC. Conclusions We found low rates of MDR-GNBs in Australian chicken and pork meat, but potential 3GCR-GNBs are common (93% specimens). Testing programs that only assess for E. coli are likely to severely underestimate the diversity of 3GCR organisms in fresh meat.

Simple Summary Piglet preweaning mortality is a major economic loss and welfare concern for the global pork industry, with the industry average sitting at approximately 15%. As such, novel methods for reducing this mortality are needed. Since research into the intestinal microbiota has provided advances in human health, in particular the impact of early life factors, it was the logical next step to synthesise the existing literature to determine the potential relevance to the pig industry. It is evident from the literature that this area of research provides promising results. However, a large gap within the literature currently exists within the lactation period in pigs. Since optimal development within early life is proving to be critical for human infants, it is crucial that further research is invested into understanding the impact of early life events on a piglet’s microbiome. It is hoped that this review will enable access to critical information for those interested in the microbiome and its potential for improving herd health on the farm. Abstract The intestinal microbiota has received a lot of attention in recent times due to its essential role in the immune system development and function. Recent work in humans has demonstrated that the first year of life is the most critical time period for microbiome development with perturbations during this time being proven to have long term health consequences. In this review, we describe the literature surrounding early life events in humans and mice that contribute to intestinal microbiota development and function, and compare this to piglets predominantly during their lactation period, which focuses on the impact lactation management practices may have on the intestinal microbiota. Although extensive research has been conducted in this area in humans and mice, little research exists in pigs during perceivably the most critical time period of development, which is the lactation period. The research reviewed outlines the importance of appropriate intestinal microbiota development. However, further research is needed in order to understand the full extent routine farm practices have on a piglet’s intestinal microbiota.

Antibacterial coatings have been accepted as a potent solution to the problem of medical-device-associated infections, which affect millions of patients worldwide. In this work, we present silver-nanoparticle-based antibacterial coatings that are highly potent against medi- cally relevant bacteria such as S. epidermidis and S. aureus but do not have apparent cytotoxicity to primary human fibroblast cells. The silver nanoparticles used in the coatings are synthesized in the presence of trisodium citrate. At a given moment, 2-mercaptosuccinc acid is added to allow for reduction of nanoparticle size and to provide the well-defined surface architecture necessary for controllable surface immobilization. Important for application, the technology is facilitated by a functional-plasma-deposited polymer interlayer. This makes it applicable to the surface of medical devices manufactured from any type of material.

Because of raising of large-scale high density prawn aquaculture techniques, production of this prawn worldwide is facing a serious threat from fatal diseases caused by nodaviruses and bacteria, particularly from the Vibrio species. The development of antibiotic resistance by Vibrio represents a potential threat to human health by exchange of resistant genes to human pathogens through food chain. This study aimed to determine antibiotic resistance profile of Vibrio isolates from giant fresh water Prawns (Macrobrachium rosenbergii) raised in Iran and to detect some antibiotic resistance genes in the isolates. A total of fifty giant fresh water prawns were processed for isolation of Vibrio species during February 2015 to August 2015. Identification of Vibrio isolates was done following standard biochemical methods. Phenotypic resistance of the isolates as determined by agar dilution method while polymerase chain reaction (PCR) method was used to detect the presence of erm, tetS, strA and sul2 genes in the isolates. Out of 50 prawns, 31 (62%) isolates of Vibrio spp. were reported, of which 20 (40%) were identified as V. parahaemolyticus, 10 (20%) were V. vulnificus and 1 (2%) were V. cholera. Over 90% of the tested strains showed susceptibility to SXT, AZM and NIT. In addition, strA and tetS genes were detected in all isolated Vibrio species. StrA gene was identified in 6 V. parahaemolyticus strains and also ermB and sul2 genes were not present in the isolate of V. cholera. The occurrence of multidrug resistance strains in the environment could be an indication of excessive usage of antibiotics in agriculture and aquaculture fields. This study has shown that giant freshwater prawns raised in Iran habour multidrug resistant Vibrio species. Refereed/Peer-reviewed

Bacteriophage therapy has demonstrated promising results towards the control of bacterial infections within the aquaculture industry as an alternative therapy to antibiotics. This current research describes the efficacy of bacteriophage therapy in controlling vibriosis within abalone (Haliotis laevigata). Two bacteriophages were isolated and used in in vitro assays to determine the effect of each specific phage on the growth of specific Vibrio harveyi isolates. To demonstrate efficacy, an in vivo bioassay was performed using abalone (H. laevigata) at a water temperature of 24 °C. Characterisation of the two isolated phages revealed they were from the family, Siphoviridae. The phages had different antimicrobial abilities towards different Vibrio harveyi isolates in the in vitro assays and the bioassay demonstrated improved survival of abalone treated with bacteriophage. The results of the bioassay showed that the negative control and phage control were statistically identical, with 100% survival, but they were different from the positive bacterial control, with a 0% survival. The bacteria + phage treated group showed increased accumulative survival of 70% compared to the positive control. This is the first study to demonstrate the efficacy of bacteriophage therapy treatment for abalone. The study demonstrates that if abalones are treated with bacteriophage shortly after Vibrio harveyi infection, the accumulative survival could be significantly increased. Refereed/Peer-reviewed

This study aimed to characterize the probiotic properties of lactic acid bacteria from the naturally fermented milk of Indonesia, namely dangke and dadih. Fifty-one representative lactic acid bacteria belonging to the species Lactobacillus Plantarum, Lactococcus lactis subsp. lactis and Enterococcus faecium were evaluated in vitro for potential probiotic properties based on their bile salt resistance, low pH tolerance, antimicrobial activity, antibiotic susceptibility and adherence to Caco-2 colon cancer cells. In addition, bacteriocin related gene (plantaricin A), bile salt hydrolase (bsh) and mannose-specific adhesin (msa) genes in the genome of lactobacilli were also examined. None of the dangke isolates, which belonged to the species L. lactis subsp. lactis tolerated low pH. However, eight of the isolates were able to grow in the presence of bile salts. It was observed that L. plantarum strain S1.30 and SL2.7 from dadih tolerated low pH, survived bile salt concentrations and were resistant to vancomycin. Furthermore, these strains also contained bacteriocin regulating gene (plantaricin A) and msa and bsh genes in their genome. However, only the strain S1.30 exhibited optimal antimicrobial activity against the selected pathogens and was able to adhere to Caco-2 cells by up to 82.24±0.14%. Antagonistic activity of L. lactis subsp. lactis from dadih and dangke was not detected. However, 73.94±1.26% adherence to Caco-2 cells was demonstrated by L. lactis subsp. lactis strain SL3.34 sourced from dangke. These results suggest that Lactobacillus plantarum strain S1.30 associated with dadih fulfilled the in vitro probiotic criteria and could be exploited for further in vivo evaluation. In addition, dadih was an effective probiotic carrier compared to dangke. Refereed/Peer-reviewed

Vaccines are an integral part of veterinary disease prevention. However there are still a significant number of veterinary diseases for which vaccines do not currently exist or where currently available vaccines do not provide adequate immunity. Adenoviruses have transitioned from tools for gene replacement therapy to bona fide vaccine delivery vehicles because of their ability to elicit potent cell-mediated and humoral responses making them ideal for use against viruses and other intracellular pathogens. Adenoviral vector based vaccines are likely to play a significant role in overcoming these problems in the future. However, this vector is under utilized in veterinary vaccine development at this time. This review focuses on adenoviral vector based vaccines developed to date and explores the potential for veterinary vaccine development based upon this platform: advantages and potential disadvantages of this technology are discussed as well as the potential for developing efficacious commercial veterinary adenoviral vector based vaccines.

Resistance to antimicrobials in enterococci from poultry has been found throughout the world and is generally recognized as associated with antimicrobial use. This study was conducted to evaluate the phenotypic and genotypic profile of enterococcal isolates of intensive (indoor) and free range chickens from 2008/09 and 2000 in order to determine the patterns of antimicrobial resistance associated with different management systems. The minimum inhibitory concentrations in faecal enterococci isolates were determined by agar dilution. Resistance to bacitracin, ceftiofur, erythromycin, lincomycin, tylosin and tetracycline was more common among meat chickens (free range and intensive) than free range egg layers (PB

Aims: To determine the antibacterial spectrum and cytotoxic activities of serrulatane compounds from the Australian plant Eremophila neglecta. Methods and Results: Antimicrobial activities of serrulatane compounds 8,19-dihydroxyserrulat-14-ene (1) and 8-hydroxyserrulat-14-en-19-oic acid (2) were tested against Gram-negative and Gram-positive bacteria including human and veterinary pathogens and some multidrug-resistant isolates. Minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of the compounds were determined by broth microdilution assay. Both compounds exhibited antibacterial activity against all Gram-positive test strains. They showed antimycobacterial activity against isolates of Mycobacterium fortuitum and Mycobacterium chelonae. Of the five Gram-negative bacteria tested, only Moraxella catarrhalis showed susceptibility to the compounds. Cytotoxic activities were tested in the Vero cell line. Compound 1 showed more activity than 2 in both antibacterial and cytotoxicity assays with cytotoxicity at concentrations similar to the MBC. Conclusions: Serrulatane compounds showed significant activity against medically important bacteria, with 1 exhibiting stronger antibacterial activity. However, they also displayed toxicity to mammalian cells. Significance and Impact of the Study: Serrulatanes are of interest as novel antibacterial compounds for use in biomedical applications; this study reports data obtained with a range of bacterial strains and mammalian cells, essential for assessing the capabilities and limitations of potential applicability of these compounds.

Mesoporous silica structures were synthesized as MCM-41 and SBA-15 from two different mole ratios of their constituents to test their capacity and feasibility for the controlled release of the natural antimicrobial allyl isothiocyanate (AITC). Pore filling by vapor phase AITC approached 100%. Infrared spectroscopy of the adsorbed phase confirmed it to be liquid-like. Controlled release as desorption was dictated by the pore size distribution of each material with up to 90% of the available AITC desorbed over 96. h. Release from the SBA-15 systems occurred as a "burst release" with 65% desorbed in the first 12. h compared with only 20% from the MCM-41 systems. The antimicrobial activity of the released (vapor-phase) ATIC was compared with that from liquid AITC in tests with the microorganisms Escherichia coli, Bacillus cereus, and Pichia anomola. The lethal activity of the released AITC against these microorganisms was unaffected by adsorption and desorption processes, demonstrating the MCM-41 and SBA-15 mesoporous silica structures represent a novel controlled release vector against selected food-borne pathogenic microorganisms. Refereed/Peer-reviewed

Aims: Temperate bacteriophages are bacterial viruses that transfer genetic information between bacteria. This phenomenon is known as transduction, and it is important in acquisition of bacterial virulence genes and antimicrobial resistance determinants. The aim of this study was to demonstrate the role of bacteriophages in gene transfer (antibiotic resistance) in enterococci. Methods and Results: Three bacteriophages from environmental samples isolated on pig host strains of Enterococcus gallinarum and Enterococcus faecalis were evaluated in transduction experiments. Antibiotic resistance was transferred from Ent. gallinarum to Ent. faecalis (tetracycline resistance) and from Ent. faecalis to Enterococcus faecium, Enterococcus hirae/durans and Enterococcus casseliflavus (gentamicin resistance). Conclusions: Bacteriophages play a role in transfer of antibiotic resistance determinants in enterococci. Significance and Impact of the Study: This study confirms previous suggestions on transduction in enterococci, in particular on interspecies transduction. Interspecies transduction is significant because it widens the range of recipients involved in antimicrobial resistance transfer.

Methicillin-resistant staphylococci (MRS) pose a challenge to clinicians and health administrators in human medicine, but MRS infections in cats and dogs are not perceived as a problem in veterinary medicine. Ten methicillin-resistant staphylococcal isolates obtained from healthy and diseased cats and dogs were subjected to partial DNA sequencing of the mecA gene. Sequence analysis shows that MRS isolates from both healthy and diseased cats and dogs can harbor the mecA gene. The mecA genes of animal isolates were identical to that found in human MRS strains, and therefore the possibility of zoonotic transfer must be considered.

1. SUMMARY Dogs and cats have become an integral part of modern society in the developed world and as such attention is given to their care and welfare. At some stage of their lives many cats and dogs suffer from skin and other superficial staphylococcal infections such as pyoderma and otitis externa and are therefore treated with antibiotics. This practice has led to the emergence of resistant staphylococci in these animals. Antimicrobial susceptibility studies in companion animals have revealed that staphylococci isolated from cats and dogs exhibit similar resistance patterns to human staphylococci and that resistance development is influenced by the frequency of use of certain antibiotics. This review examines the antibiotic resistance patterns of the most frequently isolated staphylococci from cats and dogs and the mechanisms underlying resistance. The possible transfer of methicillin-resistant staphylococci from cats and dogs to humans has been identified as a potential public health issue. Typing tools used for epidemiological differentiation of pathogenic and nonpathogenic staphylococci and for species identification studies may help to elucidate the importance or otherwise of this problem.

Background In recent decades, bacterial antibiotic resistance (especially in enterococci) has become a significant problem for human and veterinary medicine. One of the most important antibiotic resistances in enterococci, vancomycin resistance, is encoded by van gene family. Objectives The aim of this study was to investigate antibiotic resistance to vancomycin in enterococci and the genes responsible for this resistance. Materials and Methods Two-hundred and thirty enterococcal isolates from pigs (207 isolates), chickens (15 isolates) and humans (eight isolates) were phenotypically and genotypically tested for resistance to vancomycin by minimum inhibitory concentration (MIC) and polymerase chain reaction (PCR). The van genes were confirmed by gene sequencing. Results Of the total isolates, 19% were phenotypically resistant to vancomycin, while nearly 15% contained either vanC1 or vanC2 gene. One resistant E. casseliflavus isolate with pig origin (MIC > 8 μg/mL) contained both vanC1 and vanC2 genes. Furthermore, one vanC1 was found in a sensitive E. faecalis isolate of pig origin (MIC ≤ 4 μg/mL) and one vanC2 in a resistant E. faecium isolate of chicken origin (MIC > 32 μg/mL). These genes were not accompanied by other van genes. Other detected genes were vanA in 11 E. faecium isolates of chicken origin (MIC > 32 μg/mL). No vanB genes were found. Gene sequencing results showed 100% identity with GenBank reference genes. Conclusions The current report is the first report on the detection of vanC1 and vanC2 genes in one enterococcal species with pig origin. This report is important as it proves the horizontal transfer of various vanC genes to one species possibly due to the compatibility class of plasmids. Furthermore, detection of vanC genes in E. faecalis and E. faecium isolates is important as it suggests that resistance to vancomycin in non-motile enterococci can be encoded by several mechanisms.

Infections arising from bacterial adhesion and colonization on medical device surfaces are a significant healthcare problem. Silver based antibacterial coatings have attracted a great deal of attention as a potential solution. This paper reports on the development of a silver nanoparticles based antibacterial surface that can be applied to any type of material surface. The silver nanoparticles were surface engineered with a monolayer of 2-mercaptosuccinic acid, which facilitates the immobilization of the nanoparticles to the solid surface, and also reduces the rate of oxidation of the nanoparticles, extending the lifetime of the coatings. The coatings had excellent antibacterial efficacy against three clinically significant pathogenic bacteria i.e. Staphylococcus epidermidis, Staphylococcus aureus and Pseudomonas aeruginosa. Studies with primary human fibroblast cells showed that the coatings had no cytotoxicity in vitro. Innate immune studies in cultures of primary macrophages demonstrated that the coatings do not significantly alter the level of expression of pro-inflammatory cytokines or the adhesion and viability of these cells. Collectively, these coatings have an optimal combination of properties that make them attractive for deposition on medical device surfaces such as wound dressings, catheters and implants. Refereed/Peer-reviewed

Aims To evaluate the phenotypic and genotypic profiles of Campylobacter spp. from poultry faecal samples from free range or intensively raised meat chickens and free range egg layers. In addition, a case-comparison study of antibiotic resistance genes from different groups of poultry and some pig strains previously collected was carried out. Methods Resistance to different antibiotics was assessed using the agar dilution method. In addition, all the strains were tested for ampicillin (blaOXA-61), erythromycin (aph-3-1), tetracycline tet(O), streptomycin (aadE), and the energy-dependent multi-drug efflux pump (cmeB) resistance genes using multiplex polymerase chain reaction. Results The evaluation of phenotypic resistance revealed all of the strains from poultry were sensitive to ciprofloxacin, gentamicin, erythromycin or tylosin. But, widespread resistance to lincomycin (51–100%), extensive resistance to ampicillin (33·3–60·2%) and less resistance to tetracycline (5·6–40·7%) were observed in the different groups of chickens. Antibiotic resistance genes blaOXA-61, cmeB and tet(O) were found in 82·6–92·7%, 80·3–89% and 22·3–30·9% Camp. coli isolates from pigs, whilst 59–65·4% and 19·2–40·7% Camp. jejuni from chickens were found to encode blaOXA-61 and tet(O), respectively. Conclusion No significant difference between isolates from free range egg layers and meat chickens (P

There is limited information on antibiotic resistance determinants present in bacteria of aquaculture origin in Australia. The presence of integron and other resistance determinants was investigated in 129 Pseudomonasisolates derived from nine freshwater trout farms in Victoria (Australia). Polymerase chain reaction (PCR) was carried out for the detection of integrase genes Int1, Int2 and Int3, gene cassette array, integron-associated aadA, beta-lactamase resistance genes blaTEM and blaSHV. Genes coding for efflux pump mexA, mexB and oprM were also investigated as well as cadA and czr which are known to mediate resistance to cadmium. Class 1 integrons were detected in 30/129 (23 %) isolates while class 2 and class 3 was not detected in any of the isolates. aadA gene was detected in 28 of the 59 integrase positive isolates which are also resistant to streptomycin. The strA-strB, blaTEM or blaSHV genes were not detected in any of the strains. mexB was detected in 85/129 isolates and cadA gene in 59/92 isolates tested. The sequence analysis mexB from this study demonstrated similarity to the RND multidrug efflux transporter mexB and its homologue TtgB which in addition to multidrug efflux also transports toluene out of the cell. The sequence analysis of cadA confirms similarities to the cadmium translocating P-type ATPases, cadA of various Pseudomonas spp. Pseudomonas spp. carrying integrons, efflux gene and cadmium resistance genes are present in farm-raised fish and sediments even though no antibiotics were licensed for use in Australian aquaculture at the time of the study.

SUMMARYThe present study compared the genetic variation among 14 different geographical isolates of Opisthorchis viverrini sensu lato from Thailand and Lao PDR using sequence data for 2 mitochondrial DNA genes, the subunit 1 of NADH dehydrogenase gene (nad1) and cytochrome c oxidase gene (cox1). Four different nad1 haplotypes were detected among isolates, all of which were identical at the amino acid sequence level. Nucleotide sequence variation among 14 isolates ranged from 0 to 0·3% for nad1. Two different cox1 haplotypes were detected among isolates. These two haplotypes differed at 2 nucleotide positions, one of which resulted in a change in the amino acid sequence. Nucleotide sequence variation among isolates for cox1 ranged from 0 to 0·5%. Comparison of cox1 sequences of O. viverrini to those of other trematodes revealed nucleotide differences of 13–31%. A phylogenetic analysis of the cox1 sequence data revealed strong statistical support for a clade containing O. viverrini and 2 other species of opisthorchid trematodes; O. felineus and Clonorchis sinsensis.

Antibiotic resistance, particularly with the fluoroquinolones and macrolide antibiotics, has now emerged globally with thermophilic campylobacters, including Campylobacter jejuni and C. coli, giving rise to concerns about how these organisms have acquired such resistance characteristics, as well as consequences for human and animal treatment. This review examines (i) the clinical epidemiology of antibiotic resistance in human and animal thermophilic campylobacters, (ii) an update on resistance rates globally, (iii) surveillance of antimicrobial resistance in campylobacters originating from animals, particularly poultry, (iv) the role of the environment in the acquisition and transmission of antibiotic-resistant campylobacters, as well as (v) issues of biocide resistance in campylobacters.

Rhodococcus equi is a significant pathogen in foals predominantly causing a pyogranulomatous bronchopneumonia. Many vaccine candidates have been tested for the prevention of R. equi disease in foals. However, none of these have been developed for widespread commercial use. Previous studies have shown that a Th1 immune response is imperative for the protection of foals against R. equi disease. In this study a DNA and a protein vaccine based upon the well-characterised R. equi virulence-associated protein VapA were developed. The vaccines were tested in the BALB/c murine model and the results showed that both vaccine candidates elicited a Th1-type response in the host. Upon coadministration of an IL-12 expression plasmid with the DNA vaccine, an increase in the Th1 response was observed. However, when mice were challenged with 1.5 x 10(7) virulent R. equi ATCC 33701 none of the vaccinated mice showed protection apart from the mice immunised with live R. equi. These results indicate that despite their immunogenicity the VapA-based DNA and recombinant protein vaccines developed in this study were unable to prevent bacterial replication following a high-dose systemic challenge with virulent R. equi in the BALB/c model.

Linear B-cell epitopes of the Rhodococcus equi virulence-associated protein (VapA) were mapped using a synthetic peptide bank in this study. The peptides were screened in an enzyme-linked immunosorbent assay (ELISA) with a total of 70 sera from foals with current R. equi disease (51 sera), as well as from foals that had either recovered from R. equi infection 10 months previously (3 sera) or that had no known history of R. equi disease (16 sera). An epitope with the sequence NLQKDEPNGRA was identified and was universally recognized by all 51 sera from foals with R. equi disease and was not recognized by any of the other sera. There was poor reactivity between all sera and peptides relating to other areas of the VapA protein. It is proposed that an ELISA based upon a defined peptide epitope may be used in an improved serological diagnostic test for R. equi infection in foals.

Antibiotic resistance in bacteria that cause disease in man is an issue of major concern. Although misuse of antibiotics in human medicine is the principal cause of the problem, antibiotic-resistant bacteria originating in animals are contributory factors, with some types of resistance in some species of bacteria. Antibiotics are added to animal feeds to treat and prevent infections and to improve growth and production. Until recently, the major concerns about incorporation of antibiotics in animal feeds related to antibiotic residues in products from treated animals. Although, in 1969, the Swann (1969) report drew attention to the potential for antibiotic-resistant bacteria to spread from treated animals via the food chain, there was little response until the detection of vancomycin-resistant enterococci in animals fed a related glycopeptide, avoparcin. Subsequently, attention started to focus on the issue and other examples of transfer of resistant bacteria through the food chain, such as enterococci resistant to quinupristin–dalfopristin or to everninomicin, fluoroquinolone-resistant campylobacters and multiresistantEscherichia coli, and salmonella such asSalmonella typhimuriumDT104. Reviews and committees in many countries have highlighted the need for better control of licensing of antibiotics, and codes for prudent use of antibiotics by veterinary practitioners and farmers. The continued use of antibiotic growth promoters has been questioned and there is a need to ensure that antibiotics important in human medicine are not used therapeutically or prophylactically in animals.

Humans and animals intimately sharing the same environment will inevitably be exposed to each other's microbiota. When one of those organisms is a drug-resistant pathogen then logistics of disease prevention are raised to a new level of complexity. For this reason the study of methicillin resistant Staphylococcus aureus (MRSA) in man and animals is now a priority. Recent research has demonstrated the ease with which MRSA crosses species barriers and the grave potential for MRSA to cause serious disease in animals and man has been well established. However, a key feature of MRSA (as compared zoonotic, resistant Salmonella spp.) is that companion and performance animals appear to have pivotal roles in the ecology of spread of certain genotypes found in humans. In this article we summarise the major developments in animal-human MRSA with an emphasis on the most recent Australian data incriminating involvement of companion and performance animals in the ecology of spread. Refereed/Peer-reviewed

Prescottella equi (formerly Rhodococcus equi) is an intracellular pathogen that causes pyogranulomatous pneumonia in Thoroughbred foals. There is currently no vaccine available for the prevention of this disease in foals despite years of research. Cell mediated immunity is considered crucial for overcoming an infection caused by this pathogen. The virulence associated protein (VapA) is a well characterized immunogenic protein associated with this pathogen and was used to develop DNA and recombinant protein vaccines in this study. Vaccine candidates and live P. equi based vaccine were tested in BALB/c mice. Mice were challenged with virulent P.equi 2 weeks following the last boost and IgG subtypes and bacterial clearance from spleen and liver determined. The DNA vaccine elicited a significant IgG2a response indicating a Th1 biased immune response. The IFN gamma response from DNA and recombinant VapA vaccinated mice was moderate. The results of the challenge study showed that neither the recombinant VapA protein nor DNA vaccine enhanced clearance of P. equi in this model.