Dietary inclusion of the two probiotic yeast strains - S. cerevisiae RC016 and K. marxianus VM004 - improved some health parameters of post-weaned pigs, according to the team involved in the research.
The authors, writing in Veterinary and Animal Science also saw that the use of the probiotics led to increased carcass weight.
Weaning creates stress in piglets, and can result in low and variable feed intake, suboptimal weight gain, diarrhea episodes, increased morbidity and mortality. Pigs that lose weight in the first days after weaning require additional days to reach market weight. Therefore, nutrition and post-weaning management are essential to promote rapid feed intake and reduce mortality and morbidity, they said.
AGPs have demonstrated their ability to improve pig growth rate, to reduce morbidity and mortality, and to improve production and reproduction performance (Kazeem et al., 2020).
However, concerns about antimicrobial resistance (AMR) stemming from antibiotic use in livestock rearing has created regulatory and market pressures to shift away from AGPs, with researchers long evaluating potential alternatives. There has been a lot of focus on probiotics, prebiotics, symbiotics, organic acidifiers, antioxidants, and plant extracts in this respect.
Limited data
The most common probiotics are lactic acid-producing bacteria belonging to the genera Lactobacillus, Bifidobacterium, Enterococcus, and yeasts such as Saccharomyces sp. Hypothesized mechanisms of action of probiotics are reduction of the pH, and the adhesion to the intestinal epithelial surface to prevent pathogen attachment, among many others, said the research team.
Some commercially strains and/or their cell wall components have been reported to improve growth performance, immune function, and microbiota composition in weaned piglets. Studies have shown that the dietary supplementation of S. cerevisiae var. boulardii strain was effective in counteracting the toxic effects of harmful aflatoxin B1 (AFB1) in chickens. “However, they did not demonstrate the influence of this strain on productive parameters when AGPs were not present.”
In addition, there is little information regarding the use of the probiotic, K. marxianus, to improve production or health parameters in weanling piglets, found the team.
So the objective of their study was to evaluate the effect of S. cerevisiae RC016 and K. marxianus VM004 as a substitute of AGPs on the health status and productive parameters – carcass quality, organ weight, AGP, feed intake and FCR - in weaned piglets under commercial conditions in Argentina.
The study
Commercial line hybrid piglets, weaned at 21 days of age, were allotted by sex, and assigned to four pens per treatments.
Dietary treatments included a basal diet (BD) supplemented with probiotic S. cerevisiae RC016 and K. marxianus VM004, with or without antibiotics, mixed per ton of growth phases diets.
Pigs were fed ad libitum with treatments T1) BD with antibiotics (BD); T2) BD with antibiotics + S. cerevisiae; T3) BD without antibiotics + S. cerevisiae; T4) BD with antibiotics + K. marxianus; T5) BD without antibiotics + K. marxianus.
Findings
The researchers saw that when clinical signs occurred - diarrhoea, stomach ulcers, respiratory signs - they decreased with the addition of both probiotics, particularly S. cerevisiae.
The impact on productive parameters by both probiotics was akin to that of antibiotic application, said the team.
The probiotic-based diets also increased carcass weight and significantly reduced lumbar fat thickness, they added.
Dietary supplementation with probiotics did not affect organ weight, noted the researchers.
In conclusion, the study, they said, demonstrated the ability of the yeast strains to replace AGPs in weaned piglet production.
