Replacing Cereal with Ultraprocessed Foods in Pig Diets Does Not Adverse Gut Microbiota, L-glutamate Uptake, or Serum Insulin.

BACKGROUND

Using ultraprocessed food (UPF) to replace traditional feed ingredients offers a promising strategy for enhancing food production sustainability.

OBJECTIVE

To analyze the impact of salty and sugary UPF on gut microbiota, amino acids uptake, and serum analytes in growing and finishing pig.

METHODS

Thirty-six Swiss Large White male castrated pigs were assigned to 3 experimental diets: 1) standard (ST), 0% UPF; 2) 30% conventional ingredients replaced by sugary (SU) UPF; and 3) 30% conventional ingredients replaced by salty (SA) UPF. The next-generation sequencing was used to characterize the fecal microbiota. Transepithelial electrical resistance and the active uptake of selected amino acids in pig jejuna were also evaluated. Data were enriched with measurements of fecal volatile fatty acids and serum urea, minerals, and insulin. All data analyses were run in R v4.0.3. The packages phyloseq, vegan, microbiome, and microbiomeutilities were used for microbiota data analysis. The remaining data were analyzed by analysis of variance using linear mixed-effects regression models.

RESULTS

The UPF did not affect fecal microbiota abundance or biodiversity. The Firmicutes to Bacteroidetes ratio remained unaffected. SU-induced increase in the Anaerostipes genus suggested altered glucose metabolism, whereas SA increased the abundance of CAG-352 and p-2534-18B. No effects on fecal volatile fatty acids were observed. Assumptions of UPF negatively affecting small intestinal physiology were not supported by the measurements of transepithelial electrical resistance in pigs. Active amino acids uptake tests showed potential decrease in L-glutamate absorption in the SA compared with the SU diet. Blood serum analysis indicated no adverse effects on urea, calcium, magnesium, or potassium concentration but the SU group resulted in a lower blood serum insulin concentration at the time of blood collection.

CONCLUSIONS

When incorporated at 30% into a standard growing finishing diet for pigs, UPF does not have detrimental effects on gut microbiota, intestinal integrity, and blood mineral homeostasis.