Selective Maternal Seeding and Rearing Environment From Birth to Weaning Shape the Developing Piglet Gut Microbiome

From mother to piglet: the lasting influence of the maternal microbiome

BACKGROUND

Given their crucial roles in agriculture and biomedical research, promoting pig health is essential. A balanced gut microbiota is vital for immune development, metabolism and pathogen resistance, and requires optimal initial colonization by beneficial bacteria. This becomes particularly evident during early life stages, like suckling and weaning, where disruptions can lead to long-term health issues. Understanding the factors influencing microbiome development during these phases is fundamental for enhancing pig health. On these basis, rectal swab samples from eighteen sow-piglet pairs were collected at multiple time points from 7 days after birth to 10 days post-weaning, and analyzed through 16S rRNA gene sequencing. This study aims to understand the maternal influence on piglet microbiota development during the suckling-weaning period, exploring microbial diversity, composition and additional influencing factors such as age, piglet and weaning.

RESULTS

α diversity significantly increased with piglet age (p < 0.001) and stabilized upon weaning, with maternal influence and differences between individual piglet affecting variability before weaning. Post-weaning α diversity was influenced by the pen environment (contributing to 14.5-16% of the variability between piglets) rather than age. Both the sow (~ 9.6%) and age of the piglets (20-30%) had a significant impact on the microbial β diversity over the entire timeframe. Moreover, at 10 days post-weaning a significant influence of the cage mates on piglets microbial β diversity was observed (~ 24.6%). Source-tracking analysis revealed a significant maternal contribution to piglet microbiome at 7 days (31.68%), which decreased over time but remained at 13.33% post-weaning. Piglet microbiome exhibited consistency across time, with 22.55-61.23% of bacteria retained from previous stages. Cage mates contributed 53.54% to the microbiome at 10 days post-weaning. Additionally, 68.32% of piglets microbiome at 7 days was derived from sources not included in the study, decreasing to 37.6% by 10 days post-weaning. ASV-level analysis showed that the majority of maternally transmitted ASVs pre-weaning persisted until the last time point, with both beneficial bacteria and pathobionts being transmitted.

CONCLUSIONS

This study highlights the significant influence of maternal microbiota on piglet gut microbiome development, affecting both diversity and composition. Beneficial bacteria are transmitted from mothers to offspring and persist through early developmental stages, thereby emphasizing the long-lasting impact of maternal microbiome and the importance of early microbial colonization for piglet health.

Effects of organic acid-preserved cereal grains in sow diets during late gestation and lactation on the performance and faecal microbiota of sows and their offspring

BACKGROUND

Organic acids (OA) and maternal nutritional strategies have been demonstrated to promote piglet health and development. The objective of this study was to investigate the effects of incorporating OA-preserved cereal grains into sow diets during late gestation and lactation, aiming to reduce the metabolic demands of lactation while optimising offspring development and growth until slaughter. The experiment compared OA-preserved wheat and barley to conventionally dried grains, focusing on sow and offspring performance, as well as their faecal microbiota during lactation. Forty sows were blocked based on parity, body weight and back fat thickness on d 100 of gestation and assigned to one of two diets: a dried grain lactation diet and a preserved grain lactation diet. Sow faecal samples were collected at farrowing for the coefficient of apparent total tract digestibility (CATTD) of nutrients and microbial analysis. Offspring faecal samples were collected on d 10 postpartum and at weaning (d 26 postpartum) for microbial analysis.

RESULTS

Sow body weight, back fat changes, gestation and lactation length, total piglets born, wean-to-oestrus interval, and lactation efficiency were unaffected by sow diet (P > 0.05). However, sows offered the preserved grain diet exhibited improved CATTD of dry matter, nitrogen, gross energy, and neutral detergent fibre (P < 0.05). While no maternal effect was observed on offspring growth during lactation (P > 0.05), pigs from sows offered the preserved grain diet showed improved growth and feed efficiency from weaning until slaughter (d 168) compared to those from sows offered the dried grain diet (P < 0.05). The preserved grain diet also reduced the abundance of Proteobacteria in sow faeces at farrowing and in their offspring on d 10 postpartum, and improved piglet faecal scores throughout lactation (P = 0.05). At weaning, piglets from sows offered the preserved grain diet exhibited an increased abundance of Lactobacillus and reduced abundance of Alistipes in their faeces (P < 0.05).

CONCLUSION

OA-preserved grains enhanced the CATTD of nutrients in sows, promoted healthier piglet faecal scores during lactation, and improved offspring growth performance post-weaning, potentially linked to beneficial changes observed in the faecal microbiota of sows and their offspring during lactation.

The research progress on the impact of pig gut microbiota on health and production performance

Porcine gut microbiota plays a crucial role in the health and productive performance of pigs, influencing nutrient absorption, feed conversion efficiency, and ultimately, production profitability. In addition to being the primary site of digestion, the intestine houses the pig's largest immune organ, where the microbial community is essential for overall well-being. During the piglet stage, the gut microbiota undergoes a dynamic evolution, gradually adapting to the host environment. This plasticity presents opportunities to intervene and optimize its composition from early stages, enhancing animal health and development. Among the key factors in this process, dietary fiber plays a fundamental role, as its fermentation by the gut microbiota directly affects its composition and functionality, particularly in the distal small intestine, colon, and rectum. The short-chain fatty acids produced during this process not only provide continuous energy to intestinal cells but also regulate immune responses, prevent infections, and contribute to the body's homeostasis, promoting healthy growth. Despite advancements in understanding host-microbiota interactions, there is still no clear consensus on the optimal balance of gut microbiota or a precise definition of a healthy microbiota. Current research aims to identify the factors that modulate the gastrointestinal microbiota and its physiological and immune functions. Future findings will aid in developing strategies to restore gut homeostasis after external disruptions, such as stress, antibiotic use, or infections, thereby improving productivity, reducing stress-related impacts, and preventing diseases in pig production.

Bacterial profiles of the oral, vaginal, and rectal mucosa and colostrum of periparturient sows

The commensal microbiota influences the health, feeding efficiency, and reproductive performance of sows. The microbiota composition in the alimentary and genitourinary tracts and in colostrum/milk during pregnancy and lactation also impacts the microbiota and immune system, growth, and health of the piglets. Knowledge of the microbial compositions is important for evaluation of these effects and for discovering ways to improve the health and productivity of the sows. Oral, vaginal, and rectal mucosa and colostrum were sampled from 32 sows of variable parity in late pregnancy, and colostrum within 6 hours of delivery of the first piglet, on four commercial piglet-producing farms in Finland. Microbial compositions were analyzed by 16S rRNA gene amplicon sequencing. The most abundant genera of the oral microbiota were Rothia, Moraxella, and Streptococcus. The rectal microbiota was dominated by Clostridium sensu stricto 1. Streptococcus was the most abundant genus in the vagina and colostrum. Moderate differences in diversity and composition were observed between farms. The relative abundances of the genera Neisseria (MaAsLin 2 q = 0.002, ANCOMBC q = 0.005), Fusobacterium (MaAsLin 2 q = 0.008, ANCOMBC q = 0.04) and Bacteroides (MaAsLin 2 q < 0.005, ANCOMBC q = 0.06) were lower in oral samples and Romboutsia (MaAsLin 2 q = 0.07, ANCOMBC q = 0.05), Turicibacter (MaAsLin 2 q = 0.08, ANCOMBC q = 0.02) and Lachnospiraceae_UCG_007 (MaAsLin 2 q = 0.1, ANCOMBC q = 0.05) were higher in rectal samples of multiparous compared to primiparous sows. In vaginal samples there was a tendency of higher relative abundances of the genera Fusobacterium and Streptococcus in multiparous than primiparous sows. Among the differentially abundant taxa, F. necrophorum and F. nucleatum were identified in oral samples, F. gastrosuis and F. necrophorum in vaginal samples, and S. dysgalactiae in colostrum samples. This study provides a comprehensive overview of the mucosal and colostrum microbiota of periparturient sows during normal production conditions on Finnish commercial farms.

Feeding Sows with Multi-Species Probiotics During Late Pregnancy and the Lactating Period Influences IgA Concentration in Colostrum and Subsequently Increases the Survival Rate of Piglets in Porcine Epidemic Diarrhea Outbreak Herd

Porcine epidemic diarrhea (PED) virus is an important cause of diarrhea in sows and piglets [...].

Supplementation with probiotics co-cultivation improves the reproductive performance in a sow-piglet model by mother-infant microbiota transmission and placental mTOR signaling

Maternal nutritional supplementation has a profound effect on the growth and development of offspring. FAM® is produced by co-cultivation of Lactobacillus acidophilus and Bacillus subtilis and has been demonstrated to potentially alleviate diarrhea, improve growth performance and the intestinal barrier integrity of weaned piglets. This study aimed to explore how maternal FAM improves the reproductive performance through mother-infant microbiota, colostrum and placenta. A total of 40 pregnant sows (Landrace × Large White) on d 85 of gestation with a similar parity were randomly divided into two groups (n = 20): the control group (Con, basal diet) and the FAM group (FAM, basal diet supplemented with 0.2% FAM). The experimental period was from d 85 of gestation to d 21 of lactation. The results revealed that maternal supplementation with FAM significantly decreased the number of weak-born litters and the incidence of diarrhea, as well as increasing birth weight and average weaning weight, accompanied by increased levels of colostrum nutrient composition and immunoglobulins. In addition, FAM modulated the structure of mother-infant microbiota and promoted the vertical transmission of beneficial bacteria, such as Verrucomicrobiota and Akkermansia. Furthermore, FAM contributed to improving the expression of GLU and AA transporters in the placenta, and increasing the activity of the mTOR signaling pathway. Collectively, maternal supplementation with FAM during late pregnancy and lactation could improve reproductive performance through the transmission of beneficial mother-infant microbiota and placental mTOR signaling pathway and promote fetal development.

Maternal Transmission of Rotavirus to Calves and Comparison of Colostrum and Fecal Microbiota in Holstein and Hanwoo Cattle

This study aimed to evaluate rotavirus transmission to calves and analyze microbial communities in cow milk and neonatal calf feces within dairy and beef cattle. A total of 20 cattle, Hanwoo (n = 10), and Holstein (n = 10) were allotted for the study, with each breed comprising five cows and five calves. Colostrum samples were obtained from the dam, while feces were obtained from both the dam and calf. Group A rotavirus was identified in the fecal samples through real-time reverse transcription PCR (RT-qPCR). Bacterial communities present in the colostrum and bovine feces were explored using 16S rRNA metagenomic sequencing. The RT-qPCR results showed that the Cq value of one calf and one cow in the Holstein group was < 35, confirming the presence of rotavirus, whereas the Cq value in the Hanwoo group was > 35, indicating a negative result. For the bacterial communities, significant differences (p < 0.05) were found between the colostrum and fecal samples from the dams and calves, but there were no significant differences between Hanwoo and Holstein cattle. Alpha diversity analysis showed that the Chao1 and Shannon indices revealed significant differences (p < 0.05) among the sample types (cow colostrum, cow feces, and calf feces). The bacterial communities in various sample types from both Hanwoo and Holstein cattle were dominated by the phyla Firmicutes, Proteobacteria, and Bacteroidetes. In addition, the genera shared between the cow colostrum and calf fecal microbiota were higher than those shared between cow and calf feces. Overall, the current study detected rotavirus in Holstein but not in Hanwoo cattle; however, no clear evidence showed the transmission of rotavirus from dam to calf. Moreover, significant variations in bacterial compositions were observed among calf feces, cow feces, and colostrum samples, suggesting the presence of unique microbial profiles.

The Cellular Microbiome of Visceral Organs: An Inherent Inhabitant of Parenchymal Cells

The cell is the basic unit of life. It is composed of organelles and various organic and inorganic biomolecules. Recent 16S ribosomal ribonucleic acid (16S rRNA) gene sequencing studies have revealed the presence of tissue bacteria in both tumor and normal tissues. Recently, we found that the liver microbiome resided in hepatocytes. Here, we further report on the cellular microbiome in the parenchymal cells of visceral organs as inherent inhabitants. We performed 16S rRNA gene sequencing on visceral organs of male adult Sprague Dawley (SD) rats, pregnant rats, newborn rats, and fetuses and placentas; then, we performed fluorescence in situ hybridization and immunofluorescence in visceral organs. Furthermore, we performed Western blotting on nuclear and cytoplasmic extractions of visceral organs of SD rats and cell lines HepG2, Huh-7, Hepa1-6, and HSC-T6. A high abundance of 16S rRNA gene was detected in the visceral organs of male adult, pregnant, newborn, and fetal rats as well as their placentas. The number of operational taxonomic units (OTUs) of visceral bacteria was higher than that of the feces and ileum bacteria. Bacterial 16S rRNA, lipopolysaccharide (LPS), and lipoteichoic acid (LTA) were found in the parenchymal cells of visceral organs, as well as in HepG2, Huh-7, HSC-T6, and Hepa1-6 cells. LPS consistently appeared in the nucleus of cells, while LTA was mainly found in the cytoplasm. In conclusion, the cellular microbiome is an intrinsic component of cells. Gram-negative bacteria are located in the nucleus, and Gram-positive bacteria are located in the cytoplasm. This differs from the gut microbiome and may be inherited.

Composition, function, and timing: exploring the early-life gut microbiota in piglets for probiotic interventions

BACKGROUND

The establishment of a robust gut microbiota in piglets during their early developmental stage holds the potential for long-term advantageous effects. However, the optimal timeframe for introducing probiotics to achieve this outcome remains uncertain.

RESULTS

In the context of this investigation, we conducted a longitudinal assessment of the fecal microbiota of 63 piglets at three distinct pre-weaning time points. Simultaneously, we gathered vaginal and fecal samples from 23 sows. Employing 16S rRNA gene and metagenomic sequencing methodologies, we conducted a comprehensive analysis of the fluctuation patterns in microbial composition, functional capacity, interaction networks, and colonization resistance within the gut microbiota of piglets. As the piglets progressed in age, discernible modifications in intestinal microbial diversity, composition, and function were observed. A source-tracking analysis unveiled the pivotal role of fecal and vaginal microbiota derived from sows in populating the gut microbiota of neonatal piglets. By D21, the microbial interaction network displayed a more concise and efficient configuration, accompanied by enhanced colonization resistance relative to the other two time points. Moreover, we identified three strains of Ruminococcus sp. at D10 as potential candidates for improving piglets' weight gain during the weaning phase.

CONCLUSIONS

The findings of this study propose that D10 represents the most opportune juncture for the introduction of external probiotic interventions during the early stages of piglet development. This investigation augments our comprehension of the microbiota dynamics in early-life of piglets and offers valuable insights for guiding forthcoming probiotic interventions.

Effects of maternal supplementation of fish oil during late gestation and lactation on growth performance, fecal microbiota structure and post-weaning diarrhoea of offspring piglets

Homeostasis of gut microbiota is a critical contributor to growth and health in weaned piglets. Fish oil is widely reported to benefit health of mammals including preventing intestinal dysfunction, yet its protective effect during suckling-to-weaning transition in piglets remains undetermined. Low (30 g/d) and high (60 g/d) doses of n-3-rich fish oil were supplemented in sows from late gestation to lactation. Serum indicators and gut microbiota were determined to evaluate the effects of maternal fish oil on growth performance, immunity and diarrhea of piglets. DHA and EPA in the colostrum as well as serum of suckling and 1-week post-wean piglets were significantly and linearly increased by maternal supplementation of fish oil (P < 0.05). IGF1 and T3 in nursing and weaned piglets were significantly elevated by maternal fish oil (P < 0.05), and the increase of IGF1 was concerning the dosage of fish oil. Colostrum IgG, plasma IgG, IgM in suckling piglets, IgG, IgM and IgA in weaned piglets were significantly increase as maternal replenishment of fish oil increased (P < 0.05). Additionally, cortisol was significantly reduced in weaned pigs (P < 0.05), regardless of dosage. 16S rRNA sequencing revealed that α-diversity of fecal microbiota in nursery piglets, and fecal Lactobacillus genus, positively correlated with post-weaning IgA, was significantly increased by high dosage. Collectively, maternal fish oil during late pregnancy and lactation significantly promoted growth, enhanced immunity, and reduced post-weaning diarrhea in piglets, therefore facilitated suckling-to-weaning transition in piglets, which may be partially due to the altered gut microbial community.

Impact of Early Weaning on Development of the Swine Gut Microbiome

Considering that pigs are naturally weaned between 12 and 18 weeks of age, the common practice in the modern swine industry of weaning as early as between two and four weeks of age increases challenges during this transition period. Indeed, young pigs with an immature gut are suddenly separated from the sow, switched from milk to a diet consisting of only solid ingredients, and subjected to a new social hierarchy from mixing multiple litters. From the perspective of host gut development, weaning under these conditions causes a regression in histological structure as well as in digestive and barrier functions. While the gut is the main center of immunity in mature animals, the underdeveloped gut of early weaned pigs has yet to contribute to this function until seven weeks of age. The gut microbiota or microbiome, an essential contributor to the health and nutrition of their animal host, undergoes dramatic alterations during this transition, and this descriptive review aims to present a microbial ecology-based perspective on these events. Indeed, as gut microbial communities are dependent on cross-feeding relationships, the change in substrate availability triggers a cascade of succession events until a stable composition is reached. During this process, the gut microbiota is unstable and prone to dysbiosis, which can devolve into a diseased state. One potential strategy to accelerate maturation of the gut microbiome would be to identify microbial species that are critical to mature swine gut microbiomes, and develop strategies to facilitate their establishment in early post-weaning microbial communities.

Bacterial composition of a competitive exclusion product and its correlation with product efficacy at reducing Salmonella in poultry

The mature intestinal microbiome is a formidable barrier to pathogen colonization. Day-old chicks seeded with cecal contents of adult hens are resistant to colonization with Salmonella, the basis of competitive exclusion. Competitive exclusion products can include individual microbes but are commonly undefined intestinal communities taken from adult animals and in commercial production is amplified in fermentator and sold commercially in freeze dried lots. While superior to single and multiple species probiotics, reducing Salmonella colonization by multiple logs, undefined products have limited acceptance because of their uncharacterized status. In this study, the bacterial composition of the master stock, preproduction seed stocks and commercial lots of a poultry competitive exclusion product, was defined by 16S rRNA sequence analysis, targeting the 16S rRNA variable region (V1-V3). The samples contained a diversity of genera (22-52 distinct genera) however, the commercial lots displayed less diversity compared to the seeds and the master stock. Community composition varied between seeds and the master stock and was not a good predictor of potency, in terms of log₁₀ reduction in Salmonella abundance. While there was significant correlation in composition between seeds and their commercial lots, this too was a not a good predictor of potency. There was linear correlation between unclassified Actinobacteria, Peptococcus, and unclassified Erysipelotrichaceae, and Salmonella abundance (r ² > .75) for commercial seeds. However, upon review of the literature, these three genera were not consistently observed across studies or between trials that examined the correlation between intestinal community composition and Salmonella prevalence or abundance.

The Resemblance between Bacterial Gut Colonization in Pigs and Humans

Thorough understanding of the initial colonization process of human intestines is important to optimize the prevention of microbiota-associated diseases, and also to further improve the current microbial therapies. In recent years, therefore, colonization of the human gut has gained renewed interest. However, due to a lack of standardization of life events that might influence this early colonization process in humans, many generally accepted insights are based on deduction and assumption. In our review, we compare knowledge on colonization in humans with research in piglets, because the intestinal tract of pigs is remarkably similar to that of humans and the early-life events are more standardized. We assess potential similarities and challenge some concepts that have been widely accepted in human microbiota research. Bacterial colonization of the human gut is characterized by successive waves in a progressive process, to a complex gut microbiota community. After re-analyzing available data from piglets, we found that the bacterial colonization process is very similar in terms of the wave sequence and functionality of each wave. Moreover, based on the piglet data, we found that, in addition to external factors such as suckling and nutrition, the bacterial community itself appears to have a major influence on the colonization success of additional bacteria in the intestine. Thus, the colonization process in piglets might rely, at least in part, on niche dependency, an ecological principle to be considered in the intestinal colonization process in humans.