Yerba mate enhances probiotic bacteria growth in vitro but as a feed additive does not reduce Salmonella Enteritidis colonization in vivo

Abstract

Yerba mate (Ilex paraguariensis) is a tea known to have beneficial effects on human health and antimicrobial activity against some foodborne pathogens. Thus, the application of yerba mate as a feed additive for broiler chickens to reduce Salmonella colonization was evaluated. The first in vitro evaluation was conducted by suspending Salmonella Enteritidis and lactic acid bacteria (LAB) in yerba mate extract. The in vivo evaluations were conducted using preventative and horizontal transmission experiments. In all experiments, day-of-hatch chicks were treated with one of the following 1) no treatment (control); 2) ground yerba mate in feed; 3) probiotic treatment (Lactobacillus acidophilus and Pediococcus; 9:1 administered once on day of hatch by gavage); or 4) both yerba mate and probiotic treatments. At d 3, all chicks were challenged with Salmonella Enteritidis (preventative experiment) or 5 of 20 chicks (horizontal transmission experiment). At d 10, all birds were euthanized, weighed, and cecal contents enumerated for Salmonella. For the in vitro evaluation, antimicrobial activity was observed against Salmonella and the same treatment enhanced growth of LAB. For in vivo evaluations, none of the yerba mate treatments significantly reduced Salmonella Enteritidis colonization, whereas the probiotic treatment significantly reduced Salmonella colonization in the horizontal transmission experiment. Yerba mate decreased chicken BW and decreased the performance of the probiotic treatment when used in combination. In conclusion, yerba mate had antimicrobial activity against foodborne pathogens and enhanced the growth of LAB in vitro, but in vivo yerba mate did not decrease Salmonella Enteritidis colonization.

Antimicrobial Effect of Probiotics against Common Pathogens

“…Similar conclusions of finding no antagonism in vivo are noted in the study by Bratz et al [83]. Another study [79] found that the tea Yerba mate exhibited antagonistic activity in vitro but as a feed additive did not reduce S. Enteritidis colonization in vivo in broiler chickens. These studies prove that successful in vitro assays do not necessarily mean that the chosen microorganism with probiotic properties will be successful in real conditions.…”

“…Probiotic candidates have been accessed from very diverse habitats including faeces of breastfed human infants [65,69,80,85,95], faeces of healthy adults [9,15,65,70], faeces of elderly [81], faeces of children [25,96], breast milk [42], human saliva [52], vaginal isolates of healthy women [66,75], various fermented foods or beverages including raw or fermented milk [23,35,44], kefir [97], cheese [51,56,98], whey [99], yogurt [16,41], dahi [100,101], other dairy products [25,36,61], sourdough [102], sausages [17], fermented meat [24], kimchi [10,62], maize [25,59], fermented olives [103], Yerba mate [79], ragi [64], soy sauce [86], soil [104], as well as animal origin including rat faeces [71], geese [68], c...…”

Botanical alternatives to antibiotics for use in organic poultry production

“…Using new molecular techniques, this same study reported an increase of bacteria diversity and Lactobacillus populations when grape seed extract was included at 7.2 g/kg in the chicken diet. Yerba Mate extracts supported and increased the growth of Lactobacillus and Pediococcus and were antimicrobial against Salmonella and Campylobacter (González-Gil et al 2014). …”

“…Some herbs and spices have a positive influence on feed intake due to increased palatability and, thus, improve the growth rate (Brenes and Roura, 2010;Lee at al., 2004b,c). However, some phytobiotics have a negative effect on total feed intake due to the strong flavors González-Gil et al 2014).…”

“…Phytobiotics can be delivered in the feed or water depending on the composition of the product. However, a reduction in efficacy may occur when ground leaves are used as opposed to using extracts (González-Gil et al 2014). Plant extracts are typically more effective than ground leaves because the active components are concentrated in extracts.…”