Innate immune response, intestinal morphology and microbiota changes in Senegalese sole fed plant protein diets with probiotics or autolysed yeast

Abstract

The effects of using plant ingredients in Senegalese sole (Solea senegalensis) diet on immune competence and intestine morphology and microbial ecology are still controversial. Probiotics or immunostimulants can potentially alter the intestinal microbiota in a way that protects fish against pathogens. The current study aimed to examine the intestine histology and microbiota and humoral innate immune response in juvenile sole fed diets with low (35 %) or high (72 %) content of plant protein (PP) ingredients supplemented with a multispecies probiotic bacteria or autolysed yeast. Fish fed the probiotic diet had lower growth performance. Lysozyme and complement activities were significantly higher in fish fed PP72 diets than in their counterparts fed PP35 diets after 17 and 38 days of feeding. At 2 days of feeding, fish fed unsupplemented PP72 showed larger intestine section area and longer villus than fish fed unsupplemented PP35. At 17 days of feeding, fish fed unsupplemented PP72 showed more goblet cells than the other dietary groups, except the group fed yeast supplemented PP35 diet. High dietary PP level, acutely stimulate fish innate immune defence of the fish after 2 and 17 days of feeding. However, this effect does not occur after 73 days of feeding, suggesting a habituation to dietary treatments and/or immunosuppression, with a reduction in the number of the goblet cells. Fish fed for 38 days with diets supplemented with autolysed yeast showed longer intestinal villus. The predominant bacteria found in sole intestine were Vibrio sp. and dietary probiotic supplementation caused a reduction in Vibrio content, regardless of the PP level.

Probióticos do gênero Bacillus em dietas para pós-larvas de tilápia do Nilo (Oreochromis niloticus)

“…Os resultados de desempenho zootécnico não apresentaram valores significativos (P<0,05) entre os níveis de inclusão de probiótico do gênero Bacillus (Tabela 2). Resultado semelhante ao relatado por Batista et al (2016), onde o ganho de peso, índices de crescimento diário e conversão alimentar não foram afetados.…”

“…Probiótico é um promotor que confere ações benéficas para os peixes com diferentes modos de ação ao hospedeiro. Na aquicultura tem sido considerada como uma boa estratégia sustentável, pois controla patógenos que provocam doenças, mas também na nutrição, crescimento e saúde (Lazado & Caipang, 2014a;Batista et al, 2016). A ocorrência de stress é verificada por meio de manejo a ser aplicada na piscicultura, representada por maior evidencia na manipulação excessiva de transporte de peixes na intensificação que favorecem ao meio de cultivo uma condição que enfraquece o sistema imunitário que conduz a uma maior susceptibilidade a doenças e patógenos (Sado-Yuji et al, 2014;Dawood et al, 2016;De Melo Lima et al, 2018).…”

Effect of hydrolysed fish protein and autolysed yeast as alternative nitrogen sources on gilthead sea bream (Sparus aurata) growth performances and gut morphology

“…So far autolysed yeast have rarely been used as a bulk ingredient for FM replacement but rather as potential immunostimulant. A reduction of growth performances in Senegalese sole (Solea senegalensis) was observed when autolysed yeast (S. cerevisiae) was included in a plant-based diet (Batista et al 2016). These results are likely related to the replacement of fish meal with plant sources while our study suggests that when HPF or AY are used, no negative effect on fish growth performances are observed.…”

Skin-associated lactic acid bacteria from North American bullfrogs as potential control agents of Batrachochytrium dendrobatidis

“…There is only one effective practical intervention eradicating Bd based on antifungals [16], thus probiotics represent an attractive alternative tool for Bd control in nature [17–19] with potential advantages over antifungal drugs, which are difficult to apply in the wild and may have profound effects to the native microbiota of a host or ecosystem [16,20]. In aquaculture, probiotics may confer benefits to the health of their host or the environment through different modes of action including antagonistic activity against pathogens [15,20–28], enhanced competitive exclusion of pathogens through increased host microbial load and diversity [15,17,29], modulation of pathogen virulence, adhesion to host epithelial cells, stimulation of the immune response [17,30–32] and improvement of water quality [33].…”