Functional amino acids including glutamine and glutamate (Gln/Glu) play critical roles in supporting intestinal health, antioxidant defense, and metabolic regulation during periods of increased physiological demand, including late gestation and lactation in sows.
Objective: This study evaluated the effects of Gln/Glu supplementation in sow diets during late gestation and lactation on sow performance, reproductive parameters, colostrum composition, blood biomarkers, and fecal microbiota.

Methods: A total of 43 Landrace x Yorkshire sows (parity 4.0 ± 1.7; body weight 270 ± 31 kg) were allocated using a randomized complete block design with parity and body weight as blocks and fed either a control diet or a Gln/Glu-supplemented diet (10 g/kg) from day 86 of gestation until weaning (day 21 of lactation). To evaluate the effect of Gln/Glu-supplementation, reproductive and farrowing performance was measured, and colostrum, blood, and fecal samples were collected.
Results: Sows fed the Gln/Glu-supplemented diet exhibited reduced farrowing duration. Colostrum from sows fed the Gln/Glu-supplemented diet showed higher concentrations of methionine, cystine, isoleucine, leucine, alanine, and tyrosine compared to the control group, with trends for increased levels of histidine, glutamic acid, glycine, and serine. A trend toward higher average daily feed intake during lactation and increased insulin concentration was also observed. Piglet weaning weight was improved in sows fed the Gln/Glu-supplemented diet. No effects were observed on gestation weight gain, lactation weight loss, backfat thickness, body condition score, or most blood biochemical and immunological parameters. The fecal bacterial load of Escherichia coli and Clostridium perfringens was unaffected by treatment.
Conclusion: The results suggest that supplementing sow diets with Gln/Glu during late gestation and lactation may enhance farrowing efficiency, improve colostrum amino acid content, and improve neonatal growth during lactation.
Sousa MVS, Kiefer C, Reis LFL, Santos AG, Possa LO, Kim SW, Rocha GC. Glutamine and glutamate supplementation in sow diets during late gestation and lactation reduces farrowing duration, improves colostrum amino acid content, and enhances piglet weaning weight. Journal of Animal Science. 2025; skaf367. https://doi.org/10.1093/jas/skaf367

