Browsing by Author "Pinkerton, Laurette"
Now showing 1 - 5 of 5
Results Per Page
ItemThe effect of natural antimicrobials against Campylobacter spp. and its similarities to Salmonella spp, Listeria spp., Escherichia coli, Vibrio spp., Clostridium spp. and Staphylococcus spp.(Elsevier, 2020-11-13) Balta, Igori; Linton, W. Mark R.; Pinkerton, Laurette; Kelly, Carmel A.; Stef, Lavinia; Pet, Ioan; Stef, Ducu; Criste, Adriana; Gundogdu, Ozan; Corcionivoschi, NicolaeThe increased resistance of campylobacters to antibiotics required the identification and isolation of novel antimicrobials able to inhibit its virulence, to cause less or no resistance and display no host toxicity. Acquiring all this knowledge was only possible through a better understanding of their antibacterial potency and of the biological mechanisms involved attenuating the bacterial virulence factors. This review describes the most recent developments in the area by looking at the new antimicrobial interventions aiming to combat the transmission and colonisation of Campylobacter spp. and its commonalities with other pathogenic bacteria. In this review we are also looking into the most recent developments, both in vitro and in vivo, focusing on the biological mechanisms by which natural antimicrobials express their anti-pathogenic effect. Following this extensive literature search we conclude that further studies are essential to elucidate the efficiency of plant, animal, bacteria and marine-derived antimicrobials as well as their role as promising alternatives to antibiotics. ItemThe Effects of Agrimonia pilosa Ledeb, Anemone chinensis Bunge, and Smilax glabra Roxb on Broiler Performance, Nutrient Digestibility, and Gastrointestinal Tract Microorganisms(MDPI, 2022-04-26) McMurray, Rebekah L.; Ball, Elizabeth; Linton, Mark; Pinkerton, Laurette; Kelly, Carmel; Lester, Jonathan; Donaldson, Caroline; Balta, Igori; Tunney, Michael M.; Corcionivoschi, Nicolae; Situ, ChenPoultry farming is growing globally, particularly in developing countries, to meet the demands of growing populations for poultry meat and eggs. This is likely to lead to an increase in the use of antibiotics in poultry feed, thus contributing to the development and spread of antibiotic resistance which, poses a serious threat to human and animal health worldwide. One way of reducing this threat is to reduce the use of antibiotics in poultry production by finding effective and sustainable antibiotic alternatives that can be used to support poultry health and productivity. Therefore, this study evaluates the incorporation of three medicinal plants, Anemone chinensis Bunge, Smilax glabra Roxb, and Agrimonia pilosa Ledeb, in poultry feed on production performance, nutrient digestibility, and bacteria in the chicken caecum in a 35-day performance trial with 420-day-old male Ross 308 broilers. Groups of randomly selected chicks received one of six dietary treatments. These included five experimental diets of reduced nutrient specifications as a negative control (NC); with amoxicillin as a positive antibiotic control (PC1); with A. pilosa Ledeb (NC1); with A. chinensis Bunge (NC2); and with S. glabra Roxb (NC3). One other positive control diet contained the recommended nutrient specification (PC2). Weight gain and feed intake were measured weekly and used to calculate the feed conversion ratio as performance parameters. Bacteria were enumerated from chicken caecum using a traditional plating method and selective agar. S. glabra Roxb and A. chinensis Bunge showed comparable effects to amoxicillin with significantly increased weight gain in birds offered these diets, compared to those offered the negative control from days 0 to 35 (p < 0.001). S. glabra Roxb exhibited effects similar to the amoxicillin control group with an improved feed conversion ratio (p < 0.001). In addition, S. glabra Roxb decreased numbers of E. coli and Campylobacter spp. on days 21 (p < 0.05) and 35 (p < 0.01) and increased numbers of lactic acid bacteria comparable to the antibiotic group on days 14 (p < 0.001) and 35 (p < 0.01). The findings of this in vivo trial highlight the potential of S. glabra Roxb and A. chinensis Bunge as beneficial feed material to promote poultry health and productivity in the absence of antibiotics. ItemThe in vitro and ex vivo effect of Auranta 3001 in preventing Cryptosporidium hominis and Cryptosporidium parvum infection(BMC, 2017-08-31) Ch Stratakos, Alexandros; Sima, Filip; Ward, Patrick; Linton, Mark; Kelly, Carmel; Pinkerton, Laurette; Stef, Lavinia; Pet, Ioan; Iancu, Tiberiu; Pircalabioru, Gratiela; Corcionivoschi, NicolaeBackground: Cryptosporidium is a major cause of diarrhea worldwide in both humans and farm animals with no completely effective treatment available at present. In this study, we assessed the inhibitory effect of different concentrations of Auranta 3001 (0.1, 0.5 and 1%), a novel natural feed supplement, on C. hominis and C. parvum invasion of human ileocecal adenocarcinoma (HCT-8), bovine primary cells and C. parvum invasion of HCT-8, bovine primary cells and bovine intestinal biopsies. The effect of the feed supplement on the production of pro-inflammatory cytokines IL-8 and INF-γ, the anti-inflammatory cytokine IL-10, the expression of CpSUB1 protease gene during infection was also assessed by quantitative PCR (q-PCR). Transepithelial electrical resistance (TEER) was employed to measure the integrity of tight junction dynamics of the culture models. Results: Pre-treatment of intestinal cells or oocysts with the Auranta 3001 significantly reduced the invasiveness of C. hominis and C. parvum against HCT-8 and bovine primary cells in a dose dependent manner. The most pronounced reduction in the invasiveness of both parasites was observed when Auranta 3001 was present during infection. Levels of IL-8 were significantly reduced in both HCT-8 and bovine primary cells, while the levels of INF-γ and IL-10 showed opposite trends in the two cell lines during infection in the presence of Auranta 3001. CpSUB1 gene protease expression, which mediates infection, was significantly reduced suggesting that this enzyme is a possible target of Auranta 3001. Conclusions: Although, C. hominis and C. parvum use different invasion mechanisms to infect cells, the novel feed additive can significantly attenuate the entry of Cryptosporidium in HCT-8 cells, primary bovine cells and bovine intestinal biopsies and thus provide an alternative method to control cryptosporidiosis. ItemThe In Vitro and In Vivo Effect of Carvacrol in Preventing Campylobacter Infection, Colonization and in Improving Productivity of Chicken Broilers(Mary Ann Liebert, Inc., 2017-06-01) Kelly, Carmel A.; Gundogdu, Ozan; Pircalabioru, Gratiela; Cean, Ada; Scates, Pamela J.; Linton, W. Mark R.; Pinkerton, Laurette; Magowan, Elizabeth; Staf, Lavinia; Simiz, Eliza; Pet, Ioan; Stewart, Sharon; Stabler, Richard; Wren, Brendan; Dorrell, Nick; Corcionivoschi, NicolaeThe current trend in reducing the antibiotic usage in animal production imposes urgency in the identification of novel biocides. The essential oil carvacrol, for example, changes the morphology of the cell and acts against a variety of targets within the bacterial membranes and cytoplasm, and our in vitro results show that it reduces adhesion and invasion of chicken intestinal primary cells and also biofilm formation. A trial was conducted to evaluate the effects of dietary supplementation of carvacrol at four concentrations (0, 120, 200, and 300 mg/kg of diet) on the performance of Lactobacillus spp., Escherichia coli, Campylobacter spp., and broilers. Each of the four diets was fed to three replicates/trial of 50 chicks each from day 0 to 35. Our results show that carvacrol linearly decreased feed intake, feed conversion rates and increased body weight at all levels of supplementation. Plate count analysis showed that Campylobacter spp. was only detected at 35 days in the treatment groups compared with the control group where the colonization occurred at 21 days. The absence of Campylobacter spp. at 21 days in the treatment groups was associated with a significant increase in the relative abundance of Lactobacillus spp. Also, carvacrol was demonstrated to have a significant effect on E. coli numbers in the cecum of the treatment groups, at all supplementation levels. In conclusion, this study shows for the first time that at different concentrations, carvacrol can delay Campylobacter spp., colonization of chicken broilers, by inducing changes in gut microflora, and it demonstrates promise as an alternative to the use of antibiotics. ItemA Novel Natural Antimicrobial Can Reduce the in vitro and in vivo Pathogenicity of T6SS Positive Campylobacter jejuni and Campylobacter coli Chicken Isolates(Frontiers Media, 2018-09-07) Sima, Filip; Stratakos, Alexandros Ch.; Ward, Patrick; Linton, Mark; Kelly, Carmel; Pinkerton, Laurette; Stef, Lavinia; Gundogdu, Ozan; Lazar, Veronica; Corcionivoschi, NicolaeHuman campylobacteriosis is considered one of the most common foodborne diseases worldwide with poultry identified as the main source of infection accounting for 50– 80% of human cases. Highly virulent Campylobacter spp., positive for the Type VI secretion system (T6SS), which have an increased ability to adhere to and invade the host gastrointestinal epithelium are highly prevalent in poultry. Multidrug resistant strains of bacteria are rapidly evolving and therefore, new antimicrobials to supplement animal feed that are able to control Campylobacter species, are in great need. The work presented herein indicates that a novel phenolic antimicrobial, Auranta 3001, is able to reduce the adhesion and invasion of human intestinal epithelial cells (HCT- 8) by two T6SS positive chicken isolates, C. jejuni RC039 (p < 0.05) and C. coli RC013 (p < 0.001). Exposure of C. jejuni RC039 and C. coli RC013 to Auranta 3001 downregulated the expression of hcp and cetB genes, known to be important in the functionality of T6SS. Furthermore, the reduced adhesion and invasion is associated with a significant decrease in bacterial motility of both isolates (p < 0.05–p < 0.001) in vitro. Most importantly our in vivo results show that Auranta 3001 is able to reduce cecum colonization levels from log 8 CFU/ml to log 2 CFU/ml for C. jejuni RC039 and from log 7 CFU/ml to log 2 CFU/ml for C. coli RC013. In conclusion, this novel antimicrobial is able to reduce the pathogenic properties of T6SS campylobacters in vitro and also to decrease colonization in vivo.