The genus Salmonella is closely associated with foodborne outbreaks and animal diseases, and reports of antimicrobial resistance in Salmonella species are frequent. Several alternatives have been developed to control this pathogen, such as cell-free supernatants (CFS). Our objective here was to evaluate the use of lactic acid bacteria (LAB) CFS against Salmonella in vitro. Seventeen strains of LAB were used to produce CFS, and their antimicrobial activity was screened towards six strains of Salmonella . In addition, CFS were also pH-neutralized and/or boiled. Those with the best results were lyophilized. MICs of lyophilized CFS were 11.25–22.5 g l^–1. Freeze-dried CFS were also used to supplement swine and poultry feed (11.25 g kg^–1) and in vitro simulated digestion of both species was performed, with Salmonella contamination of 5×10⁶ and 2×10⁵ c.f.u. g⁻¹ of swine and poultry feed, respectively. In the antimicrobial screening, all acidic CFS were able to inhibit the growth of Salmonella . After pH neutralization, Lactobacillus acidophilus Llorente, Limosilactobacillus fermentum CCT 1629, Lactiplantibacillus plantarum PUCPR44, Limosilactobacillus reuteri BioGaia, Lacticaseibacillus rhamnosus ATCC 7469 and Pediococcus pentosaceus UM116 CFS were the only strains that partially maintained their antimicrobial activity and, therefore, were chosen for lyophilization. In the simulated swine digestion, Salmonella counts were reduced ≥1.78 log c.f.u. g^–1 in the digesta containing either of the CFS. In the chicken simulation, a significant reduction was obtained with all CFS used (average reduction of 0.59±0.01 log c.f.u. ml^–1). In general, the lyophilized CFS of L. fermentum CCT 1629, L. rhamnosus ATCC 7469 and L. acidophilus Llorente presented better antimicrobial activity. In conclusion, CFS show potential as feed additives to control Salmonella in animal production and may be an alternative to the use of antibiotics, minimizing problems related to antimicrobial resistance.

Soybean meal and poultry offal meal are protein ingredients commonly used in the formulation of commercial diets for dogs. However, there remains great variability in the data on the digestibility of each protein source. This systematic review study aimed to examine the intake, apparent nutrient digestibility coefficients and fecal output of protein sources (soybean meal and poultry offal meal) in adult dog food as reported in published studies. The article search was conducted in August 2018 in the PUBMED, SciELO, Science Direct and AGRIS indexing databases. The literature search was performed using "digestibility", "source protein" and "dog" as the main key terms combined with sub-terms to broaden the scope of the search. Criteria were defined for readability, exclusion and inclusion of articles. Results were organized in groups according to the search in the indexing databases, totaling 1,414 articles. After the works were selected following the inclusion criteria, 17 articles were evaluated in this review. According to most studies, plant-based ingredients have a less variable nutritional composition than animal-derived ingredients and poultry offal meal increases the digestibility coefficients of nutrients and energy and reduces fecal dry matter production. Factors inherent to raw-material origin, ingredient and food processing, as well as the high heterogeneity of the methodologies evaluated in the studies are directly related to the obtained results. To ensure a more accurate evaluation of the quality and of effects on the digestibility of protein sources, we recommended that articles include ingredient processing data and that the variables be evaluated under standardized study conditions.

O objetivo do trabalho foi estudar os efeitos de aditivos fitogênicos e butirato de sódio como alternativas aos antimicrobianos promotores de crescimento sobre o desempenho, digestibilidade, pH do conteúdo digestório e frequência de diarréia de leitões recém-desmamados. Um experimento em blocos casualizados completos, com duas repetições no tempo e 34 dias de duração cada, foi realizado para testar cinco tratamentos: controle (T1) dieta basal; antimicrobiano (T2) basal com 40 ppm de sulfato de colistina; fitogênico (T3) dieta basal com 500 ppm de aditivos fitogênicos microencapsulados; butirato de sódio (T4) dieta basal com 1500 ppm de butirato de sódio; fitogênico + butirato de sódio (T5) dieta basal com 500 ppm de aditivos fitogênicos + 1500 ppm de butirato de sódio. Para o desempenho e a frequência de diarréia, foram utilizados 120 leitões, oito repetições por tratamento e três animais por unidade experimental. A digestibilidade foi determinada em 60 leitões das quatro primeiras repetições, utilizan-do-se o método da coleta parcial de fezes e o óxido de cromo como marcador. Ao final do período experimental, um animal de cada baia, das quatro primeiros repetições, foi abatido para mensuração do pH do duodeno, jejuno e ceco. Foram testados contrastes específicos de importância prática. Embora, o desempenho dos leitões não tenha sido influenciado pelos tratamentos (p>0,05), o tratamento butirato de sódio (T4) apresentou os melhores resultados numéricos em ambos os períodos analisados. Também não houve diferença (p>0,05) entre os tratamentos para a frequência de diarréia e para o pH da digesta. Os leitões dos tratamentos fitogênico (T3) e butirato de sódio (T4) apresentaram a média de coeficiente de digestibilidade aparente da energia superior (p=0,07) ao dos leitões do tratamento fitogênico + butirato de sódio (T5). Assim, em condições de creche experimental, não ficou evidenciado qualquer efeito dos aditivos fitogênicos e do butirato de sódio como promotores de crescimento de leitões recém-desmamados alimentados com dietas complexas e altamente digestíveis.