Bovine Milk Oligosaccharides with Sialyllactose for Preterm Piglets

Neonatal Gut and Immune Responses to β-Casein Enriched Formula in Piglets

BACKGROUND

β-casein is the main casein constituent in human milk (HM) and a source of bioactive peptides for the developing gastrointestinal tract and immune system. Infant formulas contain less β-casein than HM, but whether different concentrations of β-casein affect tolerability and gut and immune maturation in newborns is unknown.

OBJECTIVES

Using near-term piglets as a model for newborn infants, we investigated whether increasing the β-casein fraction in bovine-based formula is clinically safe and may improve gut and immune maturation.

METHODS

Three groups of near-term pigs (96% gestation) were fed formula with bovine casein and whey protein (ratio 40:60): 1) standard skim milk casein (BCN-standard, 35% β-casein of total casein, n = 18); 2) β-casein enrichment to HM concentrations (BCN-medium, 65%, n = 19); and 3) high β-casein enrichment (BCN-high, 91%, n = 19). A reference group was fed 100% whey protein concentrate (WPC) as protein (WPC, n = 18). Intestinal and immune parameters were assessed before and after euthanasia on day 5.

RESULTS

Clinical variables (mortality, activity, body growth, and diarrhea) were similar among the groups, and no differences in intestinal or biochemical parameters were observed between BCN-standard and BCN-medium pigs. However, pigs receiving high amounts of β-casein (BCN-high) had lower small intestine weight and tended to have more intestinal complications (highest gut pathology score, permeability, and interleukin-8) than the other groups, particularly those receiving no casein (WPC pigs). Blood lymphocyte, thrombocyte, and reticulocyte counts were increased with higher β-casein, whereas eosinophil counts were reduced. In vitro blood immune cell responses were similar among groups.

CONCLUSIONS

β-casein enrichment of bovine-based formula to HM concentrations is clinically safe, as judged from newborn, near-term pigs, whereas no additional benefits to gut maturation were observed. However, excessive β-casein supplementation, beyond concentrations in HM, may potentially induce gut inflammation together with increased blood cell populations relative to natural β-casein concentrations or pure whey-based formula.

Gut development following insulin-like growth factor-1 supplementation to preterm pigs

BACKGROUND

Reduced insulin-like growth factor-1 (IGF-1) levels may contribute to impaired organ development in preterm infants. Using preterm pigs as a model, we hypothesized that IGF-1 supplementation improves health and gut development during the first three weeks of life.

METHODS

First, clinical and organ endpoints were compared between artificially-reared, cesarean-delivered preterm pigs and vaginally-delivered, sow-reared term pigs at 5, 9 and 19 days. Next, preterm pigs were treated with recombinant human IGF-1 for 19 days (2.25 mg/kg/day, systemically).

RESULTS

Relative to term pigs, preterm pigs had lower body weight, fat, bone contents, relative weights of liver and spleen and a longer and thinner intestine at 19 days. Preterm birth reduced intestinal villi heights and peptidase activities, but only at 5 and 9 days. In preterm pigs, IGF-1 reduced mortality primarily occurring from gastrointestinal complications and with a tendency towards salvaging smaller pigs. IGF-1 supplementation also increased spleen and kidney weights, small intestine length and maltase to lactase activity, reflecting gut maturation.

CONCLUSION

Preterm birth affects body composition and gut maturation in the first 1-2 weeks, but differences are marginal thereafter. Supplemental IGF-1 may improve gut health in pigs and infants in the first few weeks after preterm birth.

IMPACT

Insulin-like growth factor 1 (IGF-1) supplementation may improve gut health and development in prematurity, but whether the effects are sustained beyond the immediate postnatal period is unclear. In preterm pigs, the prematurity effects on IGF-1 and gut health deficiencies are most pronounced during the first week of life and diminishes thereafter. In preterm pigs, IGF-1 supplementation beyond the first week of life reduced mortality. The present study provides evidence of a sustained effect of IGF-1 supplementation on the gastrointestinal tract after the immediate postnatal period.

Nutritional and health effects of bovine colostrum in neonates

High concentrations of immunoglobulins, bioactive peptides, and growth factors are found in bovine colostrum (BC), the milk produced by cows in the first few days after parturition. Various biological functions make it increasingly used to provide nutritional support and immune protection to the offspring of many species, including humans. These biological functions include cell growth stimulation, anti-infection, and immunomodulation. The primary components and biological functions of colostrum were reviewed in the literature, and the authors also looked at its latent effects on the growth and development of neonates as well as on conditions such as infections, necrotizing enterocolitis, short bowel syndrome, and feeding intolerance. The importance of BC in neonatal nutrition, immune support, growth and development, and gut health has been demonstrated in a number of experimental and animal studies. BC has also been shown to be safe at low doses without adverse effects in newborns. BC supplementation has been shown to be efficient in preventing several disorders, including rotavirus diarrhea, necrotizing enterocolitis, and sepsis in animal models of prematurity and some newborn studies. Therefore, BC supplementation should be considered in cases where maternal milk is insufficient or donor milk is unavailable. The optimal age, timing, dosage, and form of BC administration still require further investigation.

Preterm pigs for preterm birth research: reasonably feasible

Preterm birth will disrupt the pattern and course of organ development, which may result in morbidity and mortality of newborn infants. Large animal models are crucial resources for developing novel, credible, and effective treatments for preterm infants. This review summarizes the classification, definition, and prevalence of preterm birth, and analyzes the relationship between the predicted animal days and one human year in the most widely used animal models (mice, rats, rabbits, sheep, and pigs) for preterm birth studies. After that, the physiological characteristics of preterm pig models at different gestational ages are described in more detail, including birth weight, body temperature, brain development, cardiovascular system development, respiratory, digestive, and immune system development, kidney development, and blood constituents. Studies on postnatal development and adaptation of preterm pig models of different gestational ages will help to determine the physiological basis for survival and development of very preterm, middle preterm, and late preterm newborns, and will also aid in the study and accurate optimization of feeding conditions, diet- or drug-related interventions for preterm neonates. Finally, this review summarizes several accepted pediatric applications of preterm pig models in nutritional fortification, necrotizing enterocolitis, neonatal encephalopathy and hypothermia intervention, mechanical ventilation, and oxygen therapy for preterm infants.

In silico analysis of the human milk oligosaccharide glycome reveals key enzymes of their biosynthesis

Human milk oligosaccharides (HMOs) form the third most abundant component of human milk and are known to convey several benefits to the neonate, including protection from viral and bacterial pathogens, training of the immune system, and influencing the gut microbiome. As HMO production during lactation is driven by enzymes that are common to other glycosylation processes, we adapted a model of mucin-type GalNAc-linked glycosylation enzymes to act on free lactose. We identified a subset of 11 enzyme activities that can account for 206 of 226 distinct HMOs isolated from human milk and constructed a biosynthetic reaction network that identifies 5 new core HMO structures. A comparison of monosaccharide compositions demonstrated that the model was able to discriminate between two possible groups of intermediates between major subnetworks, and to assign possible structures to several previously uncharacterised HMOs. The effect of enzyme knockouts is presented, identifying β-1,4-galactosyltransferase and β-1,3-N-acetylglucosaminyltransferase as key enzyme activities involved in the generation of the observed HMO glycosylation patterns. The model also provides a synthesis chassis for the most common HMOs found in lactating mothers.

Differential Brain and Cerebrospinal Fluid Proteomic Responses to Acute Prenatal Endotoxin Exposure

Chorioamnionitis (CA) is a risk factor for preterm birth and is associated with neurodevelopmental delay and cognitive disorders. Prenatal inflammation-induced brain injury may resolve during the immediate postnatal period when rapid brain remodeling occurs. Cerebrospinal fluid (CSF) collected at birth may be a critical source of predictive biomarkers. Using pigs as a model of preterm infants exposed to CA, we hypothesized that prenatal lipopolysaccharide (LPS) exposure induces proteome changes in the CSF and brain at birth and postnatally. Fetal piglets (103 days gestation of full-term at 117 days) were administered intra-amniotic (IA) lipopolysaccharide (LPS) 3 days before preterm delivery by caesarian section. CSF and brain tissue were collected on postnatal Days 1 and 5 (P1 and P5). CSF and hippocampal proteins were profiled by LC-MS-based quantitative proteomics. Neuroinflammatory responses in the cerebral cortex, periventricular white matter and hippocampus were evaluated by immunohistochemistry, and gene expression was evaluated by qPCR. Pigs exposed to LPS in utero showed changes in CSF protein levels at birth but not at P5. Complement protein C3, hemopexin, vasoactive intestinal peptide, carboxypeptidase N subunit 2, ITIH1, and plasminogen expression were upregulated in the CSF, while proteins associated with axon growth and synaptic functions (FGFR1, BASP1, HSPD1, UBER2N, and RCN2), adhesion (talin1), and neuronal survival (Atox1) were downregulated. Microglia, but not astrocytes, were activated by LPS at P5 in the hippocampus but not in other brain regions. At this time, marginal increases in complement protein C3, LBP, HIF1a, Basp1, Minpp1, and FGFR1 transcription indicated hippocampal proinflammatory responses. In conclusion, few days exposure to endotoxin prenatally induce proteome changes in the CSF and brain at birth, but most changes resolve a few days later. The developing hippocampus has high neuronal plasticity in response to perinatal inflammation. Changes in CSF protein expression at birth may predict later structural brain damage in preterm infants exposed to variable types and durations of CA-related inflammation in utero.

Role of milk carbohydrates in intestinal health of nursery pigs: a review

Intestinal health is essential for the resistance to enteric diseases and for nutrient digestion and absorption to support growth. The intestine of nursery pigs are immature and vulnerable to external challenges, which cause negative impacts on the structure and function of the intestine. Among nutritional interventions, the benefits of milk are significant for the intestinal health of pigs. Milk coproducts have traditionally been used in starter feeds to improve the growth of nursery pigs, but their use is somewhat limited due to the high costs and potential risks of excessive lactose on the intestine. Thus, understanding a proper feeding level of milk carbohydrates is an important start of the feeding strategy. For nursery pigs, lactose is considered a highly digestible energy source compared with plant-based starch, whereas milk oligosaccharides are considered bioactive compounds modulating intestinal immunity and microbiota. Therefore, milk carbohydrates, mainly composed of lactose and oligosaccharides, have essential roles in the intestinal development and functions of nursery pigs. The proper feeding levels of lactose in starter feeds could be variable by weaning age, body weight, or genetic lines. Effects of lactose and milk oligosaccharides have been broadly studied in human health and animal production. Therefore, this review focuses on the mechanisms of lactose and milk oligosaccharides affecting intestinal maturation and functions through modulation of enterocyte proliferation, intestinal immunity, and intestinal microbiota of nursery pigs.

Milk Osteopontin for Gut, Immunity and Brain Development in Preterm Pigs

Deficient levels of milk osteopontin (OPN) in infant formula may partly account for developmental differences between infants fed formula or maternal milk. We hypothesized that a milk diet supplemented with bovine milk OPN improves gut, immunity and brain development and tested this in a preterm pig model. Preterm pigs delivered by cesarean section (90% gestation) were fed raw bovine milk (CON, n = 19) or the same diet supplemented with a physiologically relevant dose of OPN (46 mg/(kg·d), n = 16). Endpoints related to clinical outcomes, systemic immunity and neurocognitive development were assessed during the study and gut tissues were collected at Day 19. Growth pattern, early motor development and most systemic immune parameters were similar between OPN and CON pigs. The OPN pigs had higher villus-to-crypt ratios than CON pigs and higher monocyte and lymphocyte counts on Day 8. Gut digestive and absorptive functions and cognitive performance (T-maze test) were similar between OPN and CON pigs. In conclusion, dietary supplementation with OPN above basal bovine milk levels induced minor improvements in gut structure and systemic immunity without any effects on cognitive performance. The minimal levels of OPN in infant formula to secure optimal adaptation in the immediate neonatal period remain to be determined.

Tailoring Human Milk Oligosaccharides to Prevent Necrotising Enterocolitis Among Preterm Infants

Necrotising enterocolitis (NEC) is a devastating disease affecting preterm infants, with little improvement in mortality rates and treatment strategies in the last 30 years. Human milk oligosaccharides (HMOs) are emerging as a potential preventive therapy, with multiple protective functions postulated. Our aim is to summarise the evidence concerning the role of HMOs in NEC development and emerging strategies to tailor the delivery of HMOs to preterm infants. Most research efforts to date have focused on supplementing preterm infants with simple oligosaccharides, which are structurally different to HMOs and derived mainly from plants. Clinical trials demonstrate limited benefits for NEC prevention arising from the use of these supplements. Alternative strategies under investigation include optimising HMOs for infants receiving donor human milk, concentrating oligosaccharides from donor human milk and from animal milks, as well as more sophisticated synthetic oligosaccharide production strategies. Critically, high quality evidence to support implementation of any of these approaches in the neonatal unit is lacking. Whether it is a specific HMO alone or a combination of HMOs that exert protective effects remains to be elucidated. Further challenges include how best to manufacture and administer oligosaccharides whilst retaining bioactivity and safety, including evaluation of the long-term effects of altering the balance of HMOs and gut microbiota in preterm infants. While several human clinical trials are underway, further research is needed to understand whether a tailored approach to oligosaccharide supplementation is beneficial for preterm infants.

Potential Benefits of Bovine Colostrum in Pediatric Nutrition and Health

Bovine colostrum (BC), the first milk produced from cows after parturition, is increasingly used as a nutritional supplement to promote gut function and health in other species, including humans. The high levels of whey and casein proteins, immunoglobulins (Igs), and other milk bioactives in BC are adapted to meet the needs of newborn calves. However, BC supplementation may improve health outcomes across other species, especially when immune and gut functions are immature in early life. We provide a review of BC composition and its effects in infants and children in health and selected diseases (diarrhea, infection, growth-failure, preterm birth, necrotizing enterocolitis (NEC), short-bowel syndrome, and mucositis). Human trials and animal studies (mainly in piglets) are reviewed to assess the scientific evidence of whether BC is a safe and effective antimicrobial and immunomodulatory nutritional supplement that reduces clinical complications related to preterm birth, infections, and gut disorders. Studies in infants and animals suggest that BC should be supplemented at an optimal age, time, and level to be both safe and effective. Exclusive BC feeding is not recommended for infants because of nutritional imbalances relative to human milk. On the other hand, adverse effects, including allergies and intolerance, appear unlikely when BC is provided as a supplement within normal nutrition guidelines for infants and children. Larger clinical trials in infant populations are needed to provide more evidence of health benefits when patients are supplemented with BC in addition to human milk or formula. Igs and other bioactive factors in BC may work in synergy, making it critical to preserve bioactivity with gentle processing and pasteurization methods. BC has the potential to become a safe and effective nutritional supplement for several pediatric subpopulations.

Translational Advances in Pediatric Nutrition and Gastroenterology: New Insights from Pig Models

Pigs are increasingly important animals for modeling human pediatric nutrition and gastroenterology and complementing mechanistic studies in rodents. The comparative advantages in size and physiology of the neonatal pig have led to new translational and clinically relevant models of important diseases of the gastrointestinal tract and liver in premature infants. Studies in pigs have established the essential roles of prematurity, microbial colonization, and enteral nutrition in the pathogenesis of necrotizing enterocolitis. Studies in neonatal pigs have demonstrated the intestinal trophic effects of akey gut hormone, glucagon-like peptide 2 (GLP-2), and its role in the intestinal adaptation process and efficacy in the treatment of short bowel syndrome. Further, pigs have been instrumental in elucidating the physiology of parenteral nutrition-associated liver disease and the means by which phytosterols, fibroblast growth factor 19, and a new generation of lipid emulsions may modify disease. The premature pig will continue to be a valuable model in the development of optimal infant diets (donor human milk, colostrum), specific milk bioactives (arginine, growth factors), gut microbiota modifiers (pre-, pro-, and antibiotics), pharmaceutical drugs (GLP-2 analogs, FXR agonists), and novel diagnostic tools (near-infrared spectroscopy) to prevent and treat these pediatric diseases.

Nutrient Restriction has Limited Short-Term Effects on Gut, Immunity, and Brain Development in Preterm Pigs

BACKGROUND

Extrauterine growth restriction (EUGR) in preterm infants is associated with higher morbidity and impaired neurodevelopment. Early nutrition support may prevent EUGR in preterm infants, but it is not known if this improves organ development and brain function in the short and long term.

OBJECTIVE

Using pigs as models for infants, we hypothesized that diet-induced EUGR impairs gut, immunity, and brain development in preterm neonates during the first weeks after birth.

METHODS

Forty-four preterm caesarean-delivered pigs (Danish Landrace × Large White × Duroc, birth weight 975 ± 235 g, male:female ratio 23:21) from 2 sows were fed increasing volumes [32-180 mL/(kg·d)] of dilute bovine milk (EUGR group) or the same diet fortified with powdered bovine colostrum for 19 d (CONT group, 50-100% higher protein and energy intake than the EUGR group).

RESULTS

The EUGR pigs showed reduced body growth (-39%, P < 0.01), lower plasma albumin, phosphate, and creatine kinase concentrations (-35 to 14%, P < 0.05), increased cortisol and free iron concentrations (+130 to 700%, P < 0.05), and reduced relative weights of the intestine, liver, and spleen (-38 to 19%, all P < 0.05). The effects of EUGR on gut structure, function, microbiota, and systemic immunity were marginal, although EUGR temporarily increased type 1 helper T cell (Th1) activity (e.g. more blood T cells and higher Th1-related cytokine concentrations on day 8) and reduced colon nutrient fermentation (lower SCFA concentration; -45%, P < 0.01). Further, EUGR pigs showed increased relative brain weights (+19%, P < 0.01), however, memory and learning, as tested in a spatial T-maze, were not affected.

CONCLUSION

Most of the measured organ growth, and digestive, immune, and brain functions showed limited effects of diet-induced EUGR in preterm pigs during the first weeks after birth. Likewise, preterm infants may show remarkable physiological adaptation to deficient nutrient supply during the first weeks of life although early life malnutrition may exert negative consequences later.

Structural features, interaction with the gut microbiota and anti-tumor activity of oligosaccharides

Some oligosaccharides are regarded as biological constituents with benefits to human health in an indirect way. They enter the intestinal tract to be fermented by the gut microbiota, causing changes in the abundance and composition of the gut microbiota and producing fermentation products such as short-chain fatty acids (SCFAs). In this review, the structural features and biological activities of eight common natural oligosaccharides were summarized, including human milk oligosaccharides (HMOS), xylo-oligosaccharides (XOS), arabinoxylo-oligosaccharides (AXOS), isomaltooligosaccharides (IMOS), chitin oligosaccharides (NACOS), mannan-oligosaccharides (MOS), galacto-oligosaccharides (GOS) and fructo-oligosaccharides (FOS). Furthermore, XOS were selected to explain the anti-tumor mechanism mediated by gut microbiota. The review aims to reveal primary structural features of natural functional oligosaccharides related to the biological activities and also provide an explanation of the anti-tumor activity of functional oligosaccharides mediated by the gut microbiota.

Some oligosaccharides are regarded as biological constituents with benefits to human health in an indirect way.

Symposium review: Dairy-derived oligosaccharides-Their influence on host-microbe interactions in the gastrointestinal tract of infants

Oligosaccharides are the third most abundant component in human milk. It is widely accepted that they play several important protective, physiological, and biological roles, including selective growth stimulation of beneficial gut microbiota, inhibition of pathogen adhesion, and immune modulation. However, until recently, very few commercial products on the market have capitalized on these functions. This is mainly because the quantities of human milk oligosaccharides required for clinical trials have been unavailable. Recently, clinical studies have tested the potential beneficial effects of feeding infants formula containing 2'-fucosyllactose, which is the most abundant oligosaccharide in human milk. These studies have opened this field for further well-designed studies, which are required to fully understand the role of human milk oligosaccharides. However, one of the most striking features of human milk is its diversity of oligosaccharides, with over 200 identified to date. It may be that a mixture of oligosaccharides is even more beneficial to infants than a single structure. For this reason, the milk of domestic animals has become a focal point in recent years as an alternative source of complex oligosaccharides with associated biological activity. This review will focus specifically on free oligosaccharides found in bovine and caprine milk and the biological roles associated with such structures. These dairy streams are ideal sources of oligosaccharides, given their wide availability and use in so many regularly consumed dairy products. The aim of this review was to provide an overview of research into the functional role of bovine and caprine milk oligosaccharides in host-microbial interactions in the gut and provide current knowledge related to the isolation of oligosaccharides as ingredients for incorporation in functional or medical foods.

Alpha-Lactalbumin Enriched Whey Protein Concentrate to Improve Gut, Immunity and Brain Development in Preterm Pigs

Human milk is rich in nutritional factors, such as alpha-lactalbumin (α-Lac), and important for neonatal development, but nutrient supplementation may be required for optimal growth. Using a pig model, we hypothesized that α-Lac-enriched whey protein concentrate (WPC) supplementation improves neonatal development. Cesarean-delivered preterm pigs were fed either dilute bovine milk (REF) or REF milk supplemented with WPC with normal (STANDARD-ALPHA) or high (HIGH-ALPHA) α-Lac. Clinical, gut, immune and cognitive endpoints (open field, T-maze) were assessed and tissues collected at Day 19. The growth of STANDARD-ALPHA and HIGH-ALPHA were higher than REF (31 vs. 19 g/kg/d). Most organ weights, gut, immunity and brain variables were similar between WPC groups. HIGH-ALPHA had a higher bone mineral content, colon microbial diversity and an abundance of specific bacteria and microbial metabolites, and tended to show a faster food transit time (p = 0.07). Relative to REF, WPC pigs showed higher relative organ weights, blood amino acids, blood neutrophil function, and microbial metabolites, but lower brush-border enzyme activities and plasma cortisol. Cognition outcomes did not differ among the groups. In conclusion, WPC supplementation of milk improved some growth, gut and immunity parameters in preterm pigs. However, increasing the α-Lac content beyond human milk levels had limited effects on the immature gut and developing brain.

Supplemental Insulin-Like Growth Factor-1 and Necrotizing Enterocolitis in Preterm Pigs

Background: Recombinant human IGF-1/binding protein-3 (rhIGF-1/BP-3) is currently tested as a therapy in preterm infants but possible effects on the gut, including necrotizing enterocolitis (NEC), have not been tested. The aim of this study was to evaluate if rhIGF-1/BP-3 supplementation in the first days after birth negatively affects clinical variables like growth, physical activity, blood chemistry and hematology and gut maturation (e.g., intestinal permeability, morphology, enzyme activities, cytokine levels, enterocyte proliferation, NEC lesions), using NEC-sensitive preterm pigs as a model for preterm infants. Methods: Preterm pigs were given twice daily subcutaneous injections of rhIGF-1/BP-3 or vehicle. Blood was collected for IGF-1 measurements and gut tissue for NEC evaluation and biochemical analyses on day 5. Results: Baseline circulating IGF-1 levels were low in preterm pigs compared with near-term pigs reared by their mother (<20 vs. 70 ng/ml). Injection with rhIGF-1/BP-3 resulted in increased plasma IGF-1 levels for up to 6 h after injection (>40 ng/mL). rhIGF-1/BP-3 treatment reduced the incidence of severe NEC lesions (7/24 vs.16/24, p = 0.01) and overall NEC severity (1.8 ± 0.2 vs. 2.6 ± 0.3, p < 0.05, with most lesions occurring in colon). In the small intestine, villi length (405 ± 25 vs. 345 ± 33 μm) and activities of the brush border peptidases aminopeptidase N and dipeptidylpeptidase IV were increased in rhIGF-1/BP-3 treated pigs, relative to control pigs (+31-44%, both p < 0.05). The treatment had no effects on body weight, blood chemistry or hematology, except for an increase in blood leucocyte and neutrophil counts (p < 0.05, i.e., reduced neonatal neutropenia). Likewise, rhIGF-1/BP-3 treatment did not affect intestinal tissue cytokine levels (IL-1β, IL-6, IL-8, TNFα,), enterocyte proliferation, goblet cell density, permeability or bacterial translocation to the bone marrow. Conclusion: Supplemental rhIGF-1/BP-3 did not negatively affect any of the measured variables of clinical status or gut maturation in preterm pigs. Longer-term safety and efficacy of exogenous rhIGF-1/BP-3 to support maturation of the gut and other critical organs in preterm newborns remain to be investigated in both pigs and infants.

Bovine Milk Oligosaccharides with Sialyllactose Improves Cognition in Preterm Pigs

Optimal nutrition is important after preterm birth to facilitate normal brain development. Human milk is rich in sialic acid and preterm infants may benefit from supplementing formula with sialyllactose to support neurodevelopment. Using pigs as models, we hypothesized that sialyllactose supplementation improves brain development after preterm birth. Pigs (of either sex) were delivered by cesarean section at 90% gestation and fed a milk diet supplemented with either an oligosaccharide-enriched whey with sialyllactose (n = 20) or lactose (n = 20) for 19 days. Cognitive performance was tested in a spatial T-maze. Brains were collected for ex vivo magnetic resonance imaging (MRI), gene expression, and sialic acid measurements. For reference, term piglets (n = 14) were artificially reared under identical conditions and compared with vaginally born piglets naturally reared by the sow (n = 12). A higher proportion of sialyllactose supplemented preterm pigs reached the T-maze learning criteria relative to control preterm pigs (p < 0.05), and approximated the cognition level of term reference pigs (p < 0.01). Furthermore, supplemented pigs had upregulated genes related to sialic acid metabolism, myelination, and ganglioside biosynthesis in hippocampus. Sialyllactose supplementation did not lead to higher levels of sialic acid in the hippocampus or change MRI endpoints. Contrary, these parameters were strongly influenced by postconceptional age and postnatal rearing conditions. In conclusion, oligosaccharide-enriched whey with sialyllactose improved spatial cognition, with effects on hippocampal genes related to sialic acid metabolism, myelination, and ganglioside biosynthesis in preterm pigs. Dietary sialic acid enrichment may improve brain development in infants.