Porcine epidemic diarrhea virus (PEDV) is a coronavirus which causes severe diarrhea and fatal dehydration in piglets. In general, probiotic supplements could enhance recovery and protect piglets against enteric pathogens. Seven local lactic acid bacteria (LAB), (Ent. faecium 79N and 40N, Lact. plantarum 22F, 25F and 31F, Ped. acidilactici 72N and Ped. pentosaceus 77F) from pig feces were well-characterized as high potential probiotics. Cell-free supernatants (CFS) and live LAB were evaluated for antiviral activities by co-incubation on Vero cells and challenged with a pandemic strain of PEDV isolated from pigs in Thailand. Cell survival and viral inhibition were determined by cytopathic effect (CPE) reduction assay and confirmed by immunofluorescence. At 1:16, CFS dilution (pH 6.3-6.8) showed no cytotoxicity in Vero cells and was therefore used as the dilution for antiviral assays. The diluted CFS of all Lact. plantarum showed the antiviral effect against PEDV; however, the same antiviral effect could not be observed in Ent. faecium and Pediococcus strains. In competitive experiment, only live Lact. plantarum 25F and Ped. pentosaceus 77F showed CPE reduction in the viral infected cells to <50% observed field area. This study concluded that the CFS of all tested lactobacilli, and live Lact. plantarum (22F and 25F) and Pediococcus strains 72N and 77F could reduce infectivity of the pandemic strain of PEDV from pigs in Thailand on the target Vero cells.
Lactic acid bacteria (LAB) are used as a probiotic alternative to antibiotics in livestock production. Microencapsulation technology is widely used for probiotic preservation. A variety of microencapsulation protocols have been proposed and compared based on chemicals and mechanical procedures. This study aimed to develop a double-encapsulated coating from alginate (1.5%) and chitosan (0.5%) by extrusion, emulsion, and spray drying methods using the LAB strains Lactobacillus plantarum strains 31F, 25F, 22F, Pediococcus pentosaceus 77F, and P. acidilactici 72N, and to monitor the basic probiotic properties of the encapsulated prototypes. The final products from each microencapsulation protocol were analysed for their appearance, probiotic properties and viable cell count. Using the spray drying method, particles smaller than 15 μm in diameter with a regular spherical shape were obtained, whereas the other methods produced larger (1.4–52 mm) and irregularly shaped microcapsules. After storage for 6 months at room temperature, the LAB viability of the spray-dried particles was the highest among the three methods. In all the LAB strains examined, the encapsulated LAB retained their probiotic properties in relation to acid-bile tolerance and antibacterial activity. This study highlights the efficacy of double-coating microencapsulation for preserving LAB properties and survival rate, and demonstrates its potential for probiotic application in livestock farms.
The lactic acid bacteria (LAB) Lactobacillus plantarum (strains 22F and 25F) and Pediococcus acidilactici (strain 72N) have appeared promising as replacements for antibiotics in in vitro studies. Microencapsulation, especially by the spray-drying method, has been used to preserve their numbers and characteristics during storage and digestion. This study compared the efficacy of these strains and their microencapsulated form with antibiotic usage on growth performance, faecal microbial counts, and intestinal morphology in nursing-finishing pigs. A total of 240 healthy neonatal pigs were treated on days 0, 3, 6, 9, and 12 after cross-fostering. Sterile peptone water was delivered orally to the control and antibiotic groups. Spray-dried Lactobacillus plantarum strain 22F stored for 6-months was administered to piglets in the spraydry group. Three ml of each the three fresh strains (109 CFU/mL) were orally administered to piglets in each group. All pigs received the basal diets, but these were supplemented with routine antibiotic for the antibiotic group. Pigs in all the probiotic supplemented groups exhibited a better average daily gain and feed conversion ratio than those of the controls in the nursery and grower phases. Probiotic supplementation increased viable lactobacilli and decreased enterobacterial counts. Antibiotic additives reduced both enterobacterial and lactobacilli counts. Villous height and villous height:crypt depth ratio were greater in probiotic and antibiotic supplemented pigs comparing to the controls, especially in the jejunum. The results demonstrated the feasibility of using these strains as a substitute for antibiotics and the practicality of the microencapsulation protocol for use in swine farms.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.