Development Of Intestinal Microbiota Research Articles

Exploring the impact of maternal factors and dietary habits on human milk oligosaccharide composition in early breastfeeding among Mexican women

Human milk oligosaccharides (HMOs) promote adequate intestinal microbiota development and favor the immune system's maturation and cognitive development. In addition to non-modifiable factors, HMOs composition can be influenced by other factors like body mass index and eating habits, but the reports are discrepant. The aim of this work was to describe the correlation between maternal factors and HMOs concentration in colostrum in 70 women from northeastern Mexico categorized into women with normal weight and women with overweight or obesity. The absolute concentration of six HMOs were significantly lower in women with overweight or obesity compared to women with normal weight (LNFPI p = 0.0021, 2’-FL p = 0.0304, LNT p = 0.0492, LNnT p = 0.00026, 3’-SL p = 0.0476, 6’-SL p = 0.00041). Another main finding was that the frequency of consumption of food groups such as vegetables, fruits and meats was positively correlated to specific HMOs (Poblano chili and 2’-FL; rs = 0.702, p = 0.0012; Orange or tangerine and 3-FL; rs = 0.428, p = 0.0022; Chicken and 2'-FL; rs = 0.615, p = 0.0039). This study contributes to the elucidation of how maternal factors influence the composition of HMOs and opens possibilities for future research aimed at mitigating overweight or obesity, consequently improving the quality of human milk.

Comparative Effect of Breast Milk and Infant Formulae on Neonatal Gut Microbiome within Katsina Metropolis

Study’s Novelty/ Excerpt This study explored the impact of breast milk versus infant formula on the gut microbiota of neonates in Katsina metropolis, revealing significant differences in bacterial composition and fecal pH between the two groups. Exclusively breastfed infants exhibited a lower fecal pH (5.09±0.1) and higher weights, with similar levels of Escherichia spp. and Bifidobacterium spp., while formula-fed infants showed a higher fecal pH (5.9±0.1) and differences in Escherichia spp. loads. Despite advances in infant formula enrichment, the study underscores the distinct influence of breast milk on neonatal gut microbiota composition and health. Full Abstract Numerous studies conducted in recent years have highlighted the intricate nature of the neonatal gut microbiome, influenced by various intrinsic and extrinsic factors. One significant factor in this regard is the type of feeding, which has a substantial impact on the development of intestinal microbiota in early infancy. This study aimed to compare the effects of breast milk and infant formulae on the gut microbiota of newborns in Katsina metropolis. Faecal samples were obtained from 46 neonates (33 exclusively breastfed, 10 formula-fed, and 3 mix-fed) and analyzed using a culture-dependent method. Colony enumerations and pH measurements were conducted for comparison between the groups. The mean weight of the participants was 2.88±0.1 kg, with exclusively breastfed infants (BFI) weighing significantly more (p = 0.03) than formula-fed infants (FFI). The bacteria selected for analysis (Bifidobacterium spp., Staphylococcus spp., Escherichia spp., and Lactobacillus spp.) were present in all feeding groups. Among BFI, similar levels of Escherichia spp. and Bifidobacterium spp. (61.17 CFU/g and 61.38 CFU/g respectively) were observed. Staphylococcus spp. constituted the majority of the bacterial load (32%) in both BFI and FFI groups. Apart from Escherichia spp. (p = 0.01), no significant differences were noted in the levels of all cultured bacteria across the feeding groups. The disparity in Escherichia spp. load was evident between BFI and MFI (p = 0.01), as well as FFI and MFI (p = 0.02) only. There was no overall significant correlation between bacterial load and mode of delivery within the feeding groups (p = 0.6). The average faecal pH of breastfed infants (5.09±01) was significantly lower (p = <0.001) compared to the formula-fed group (5.9±0.1). Despite advancements in enriching infant formulae with probiotics and other bifidogenic substances, subtle differences in fecal bacterial load compared to breast milk persist, highlighting the significant influence of both feeding methods on the composition and functionality of the neonatal gut microbiome

Biomonitoring of Dietary Mycotoxin Exposure and Associated Impact on the Gut Microbiome in Nigerian Infants.

Mycotoxins are toxic chemicals that adversely affect human health. Here, we assessed the influence of mycotoxin exposure on the longitudinal development of early life intestinal microbiota of Nigerian neonates and infants (NIs). Human biomonitoring assays based on liquid chromatography tandem mass spectrometry were applied to quantify mycotoxins in breast milk (n = 68) consumed by the NIs, their stool (n = 82), and urine samples (n = 15), which were collected longitudinally from month 1-18 postdelivery. Microbial community composition was characterized by 16S rRNA gene amplicon sequencing of stool samples and was correlated to mycotoxin exposure patterns. Fumonisin B1 (FB1), FB2, and alternariol monomethyl ether (AME) were frequently quantified in stool samples between months 6 and 18. Aflatoxin M1 (AFM1), AME, and citrinin were quantified in breast milk samples at low concentrations. AFM1, FB1, and ochratoxin A were quantified in urine samples at relatively high concentrations. Klebsiella and Escherichia/Shigella were dominant in very early life stool samples (month 1), whereas Bifidobacterium was dominant between months 3 and 6. The total mycotoxin levels in stool were significantly associated with NIs' gut microbiome composition (PERMANOVA, p < 0.05). However, no significant correlation was observed between specific microbiota and the detection of certain mycotoxins. Albeit a small cohort, this study demonstrates that mycotoxins may influence early life gut microbiome composition.

Supplemental Feeding Implementation: Window of Opportunities for the Intestinal Microbiota Development and Immune Responses Modulation

This review summarizes stages of intestinal microbiota development in infant and immune responses modulation associated to these stages. The leading role of breastfeeding in the optimal microbiota and associated immune responses development during the first half of child’s life is presented. The biological feasibility of supplemental feeding implementation at the second window of opportunity (4–6 months) is justified, as well as role of supplementation products (including cereal) in adult microbiota development.

Effect of multi-strain bifidobacteria supplementation on intestinal microbiota development in low birth weight neonates: a randomized controlled trial

Effect of multi-strain bifidobacteria supplementation on intestinal microbiota development in low birth weight neonates: a randomized controlled trial

Derangement of the infant microbiome development: what a pediatrician needs to know. A review

The research on the microbiome and microbiota of different human ecological niches and their impact on human health showed a significant breakthrough in the last decade. It is known that minor microbial contamination is present even in the fetus in utero, inducing immunological resistance. Immediately after birth, the baby rapidly becomes colonized by maternal and environmental microorganisms. The mode of delivery impacts the number of microbes and species composition and subsequent changes in the infant's immune response. A high risk of early onset of atopic march has been reported in children born by cesarean section and treated with antibacterial drugs in early life. This paper reviews the results of recent studies of the effect of the probiotic based on the two most studied strains of Lactobacillus rhamnosus GG and Bifidobacterium lactis BS01 (Probielle Baby) on intestinal microbiota development and the prospects of its use for correcting disorders in children at high risk of atopy.

The difference of intestinal microbiota composition between Lantang and Landrace newborn piglets

BackgroundThe early development of intestinal microbiota plays a fundamental role in host health and development. To investigate the difference in the intestinal microbial composition between Lantang and Landrace newborn piglets, we amplified and sequenced the V3-V4 region of 16 S rRNA gene in jejunal microbiota of Lantang and landrace newborn.ResultsThe findings revealed that the dominant phyla in the jejunum of Lantang piglets were Firmicutes, Actinobacteria and Bacteroidetes, while the dominant phyla of Landrace is Proteobacteria and Fusobacteria. Specifically, Corynebacterium_1, Lactobacillus, Rothia, Granulicatella, Corynebacteriales_unclassified, Corynebacterium, Globicatella and Actinomycetales_unclassified were found to be the dominant genera of Lantang group, while Clostridium_sensu_stricto_1, Escherichia-Shigella, Actinobacillus and Bifidobacterium were the dominant genera of Landrace. Based on the functional prediction of bacteria, we found that bacterial communities from Lantang samples had a significantly greater abundance pathways of fatty acid synthesis, protein synthesis, DNA replication, recombination, repair and material transport across membranes, while the carrier protein of pathogenic bacteria was more abundant in Landrace samples.ConclusionsOverall, there was a tremendous difference in the early intestinal flora composition between Landang and Landrace piglets, which was related to the breed characteristics and may be one of the reasons affecting the growth characteristics. However, more further extensive studies should be included to reveal the underlying relationship between early intestinal flora composition in different breeds and pig growth characteristics.

Effects of Sodium Butyrate Supplementation in Milk on the Growth Performance and Intestinal Microbiota of Preweaning Holstein Calves.

The aim of the present study was to investigate the effects of sodium butyrate (SB) supplementation on the growth and intestinal microbiota of preweaning dairy calves. Eighty newborn Holstein calves (56 female and 24 male) were randomly allocated to four treatment groups with 20 calves each (14 female and 6 male). The suckling milk for the four treatments was supplemented with 0, 4.4, 8.8, or 17.6 g/d SB. During the 6-week experiment, dry matter intake was recorded daily, body weight was measured weekly, and rectal fecal samples were collected in the 2nd week. The V3-V4 hypervariable regions of the microbial 16S rRNA were amplified and then sequenced. SB supplementation elevated average daily gains (ADGs) in the first and second weeks. The optimal SB supplementation level for the whole preweaning period was 8.78 g/d, as revealed by analyzing the whole preweaning period ADG using second-order polynomial regression (quadratic) equations. The alpha diversity (Shannon diversity index), beta diversity, core phyla and genera, and function of the intestinal microbiota were affected by SB supplementation. In addition, the Shannon diversity index and core phyla and genera of the intestinal microbiota were correlated with calf growth-related indices. Overall, SB supplementation in suckling milk improved the growth performance and intestinal microbiota development of dairy calves in a quadratic manner, and regression analysis indicated an optimal supplementation level of 8.78 g/d.

Microbial Diversity and Correlation between Breast Milk and the Infant Gut.

The gut microbiota is significant for infants to grow and develop in the early stages of life. The breast milk microbiota directly or indirectly influences colonizing and the development of early infant intestinal microbiota. Therefore, we wanted to study the microbial diversity and correlation between breast milk and the infant gut. By sequencing the 16S rRNA V3-V4 regions of microbiome in infant feces 1, 14, 20, 30, and 90 days after delivery as well as those in breast milk using Illumina NovaSeq, we studied the component of microbiome in both human milk and infant stools, analyzed the diversity of microbiota, and explored the relationship between them. We found that the richest bacteria in breast milk were Acinetobacter, Stenotrophomonas, Sphingopyxis, Pseudomonas, and Streptococcus, with a small amount of Lactobacillus, Bifidobacterium, and Klebsiella. The infant feces were abundant in Bifidobacterium, Escherichia-Shigella, Klebsiella, Streptococcus, Serratia, Bacteroides, and Lactobacillus, with a small number of Acinetobacter and Pseudomonas. Acinetobacter, Bifidobacterium, Klebsiella, and Lactobacillus appeared in the breast milk and infant feces, suggesting that they were transferred from the breast milk to the infant's gut.

Agaricus subrufescens fermented rye affects the development of intestinal microbiota, local intestinal and innate immunity in suckling-to-nursery pigs

BackgroundAgaricus subrufescens is considered as one of the most important culinary-medicinal mushrooms around the world. It has been widely suggested to be used for the development of functional food ingredients to promote human health ascribed to the various properties (e.g., anti-inflammatory, antioxidant, and immunomodulatory activities). In this context, the interest in A. subrufescens based feed ingredients as alternatives for antibiotics has also been fuelled during an era of reduced/banned antibiotics use. This study aimed to investigate the effects of a fermented feed additive -rye overgrown with mycelium (ROM) of A. subrufescens—on pig intestinal microbiota, mucosal gene expression and local and systemic immunity during early life. Piglets received ROM or a tap water placebo (Ctrl) perorally every other day from day 2 after birth until 2 weeks post-weaning. Eight animals per treatment were euthanized and dissected on days 27, 44 and 70.ResultsThe results showed ROM piglets had a lower inter-individual variation of faecal microbiota composition before weaning and a lower relative abundance of proteobacterial genera in jejunum (Undibacterium and Solobacterium) and caecum (Intestinibacter and Succinivibrionaceae_UCG_001) on day 70, as compared to Ctrl piglets. ROM supplementation also influenced gut mucosal gene expression in both ileum and caecum on day 44. In ileum, ROM pigs showed increased expression of TJP1/ZO1 but decreased expression of CLDN3, CLDN5 and MUC2 than Ctrl pigs. Genes involved in TLR signalling (e.g., TICAM2, IRAK4 and LY96) were more expressed but MYD88 and TOLLIP were less expressed in ROM pigs than Ctrl animals. NOS2 and HIF1A involved in redox signalling were either decreased or increased in ROM pigs, respectively. In caecum, differentially expressed genes between two groups were mainly shown as increased expression (e.g., MUC2, PDGFRB, TOLLIP, TNFAIP3 and MYD88) in ROM pigs. Moreover, ROM animals showed higher NK cell activation in blood and enhanced IL-10 production in ex vivo stimulated MLN cells before weaning.ConclusionsCollectively, these results suggest that ROM supplementation in early life modulates gut microbiota and (local) immune system development. Consequently, ROM supplementation may contribute to improving health of pigs during the weaning transition period and reducing antibiotics use.

Supplementing oat hulls to the diet of suckling piglets altered their intestinal tract and colonic microbiota development.

Current study evaluated the effect of a fine and coarsely ground insoluble dietary fibre source on the gastrointestinal development of suckling pigs. Oat hulls (OH) were selected as a model feedstuff, rich in cellulose, lignin, and insoluble dietary fibre. Three experimental supplemental diets were formulated: a finely ground, low fibre and nutrient dense diet served as control (CON). For the 2 high fibre diets, 15% heat-treated starch in CON was exchanged with OH, either finely (OH-f) or coarsely ground (OH-c). Litters of 10 primi- and multiparous sows (mean litter size 14.6±0.84) were used. Within a litter, experimental diets were allotted to triplets of 4 piglets. From approximately 12d of age, piglets' individual feed intakes were recorded 2 times per day when separated from their dam for 70min. Piglets could suckle with their dam for the remainder of the day. On d 24 and 25, from the total pool of 120 piglets, seven healthy well-eating piglets per treatment were selected for post-mortem evaluation, resulting in 14 replicates per treatment. Consumption of OH-c and OH-f did not impede clinical health and production performance of piglets. The full stomach weights tended to be greater for OH-c compared to OH-f whereas CON was intermediate (P=0.083). Supplementing OH significantly increased ileal villus height and caecal dry matter concentration (P<0.05). For the colon, OH increased its length, contents weight, short-chain fatty acid concentration and reduced total bacterial count as well as γ-proteobacteria count and proportion (P<0.05). The OH-c treatment specifically increased full gastrointestinal tract weight and caecum contents weight compared to piglets fed CON and OH-f. Furthermore, OH-c reduced colonic crypt depth when compared to OH-f (P=0.018). In conclusion, supplementing OH to a diet for suckling piglets exerted subtle developmental effects on gastrointestinal morphology and colonic microbial community. These effects were largely independent from the particle size of the OH.

Грудное вскармливание: первая ступень на пути к формированию сбалансированного состава кишечной микробиоты как один из способов профилактики некоторых социально значимых заболеваний

The non-systematic literature review describes the mechanisms by which breastfeeding prevents the development of the metabolic syndrome and socially significant diseases associated with it: obesity, diabetes type 2 and atopic diseases. One of the mechanisms of metabolic programming is the effect of breast milk on the development of the infant's intestinal microbiota. Human milk oligosaccharides can stimulate the growth of commensal bacteria. Cytokines, secretory immunoglobulins, leukocytes, lactoferrin and lysozyme can prevent colonization by pathogenic microorganisms and prevent an increase in the permeability of the intestinal barrier, the absorption of bacterial metabolic products, including lipopolysaccharide, and the development of systemic inflammation, including inflammation adipose tissue. Polyunsaturated fatty acids from breast milk prevent adipocyte hypertrophy at an early age and the development of obesity in the adults. Adiponectin prevents insulin resistance, other hormones that are part of breast milk influence the eating habits of children and prevent weight gain in adulthood. The inclusion of breast milk components in artificial mixtures has the potential to prevent the development of many socially significant diseases.

New Strategies for Enhancement of Infant Milk Formulas Composition

This article covers the issues of remodeling breast milk’s protective properties during creating infant milk formulas. First of all, this concerns the conditions for normal intestinal microbiota development in growing organism. Its quantitative and qualitative features are the trigger of either sanogenetic, or pathological immune and metabolic reactions, and also determine gut-brain axis functioning. The protective significance of prebiotic composition diversity of mammalian milk and the inductive role of breast milk oligosaccharides are shown. The modern concept of synbiotics role in gastrointestinal tract and other systems functioning, as well as the use of modern synbiotics in the creation of infant formulas (available Russian formula included) are presented.

Increased Proportion of Fiber-Degrading Microbes and Enhanced Cecum Development Jointly Promote Host To Digest Appropriate High-Fiber Diets.

Previous study found that appropriate high-fiber diet (containing 19.10% total dietary fiber [TDF], treatment II) did not reduce apparent fiber digestibility of Chinese Suhuai finishing pigs and increased the yield of short-chain fatty acids (SCFAs), but too high-fiber diet (containing 24.11% TDF, treatment IV) significantly reduced apparent fiber digestibility compared with normal diet (containing 16.70% TDF, control group). However, characteristics of microbiota at the species level and histological structure in pigs with the ability to digest appropriate high-fiber diets were still unknown. This study conducted comparative analysis of cecal physiology and microbial populations colonizing cecal mucosa. The results showed intestinal development indexes including cecum length, densities of cecal goblet cells, and renewal of cecal epithelial cells in treatment II and IV had better performance than those in the control. Paludibacter jiangxiensis, Coprobacter fastidiosus, Bacteroides coprocola CAG:162, Bacteroides barnesiae, and Parabacteroides merdae enriched in treatment II expressed large number of glycoside hydrolase (GH)-encoding genes and had the largest number of GH families. In addition, pathogenic bacteria (Shigella sonnei, Mannheimia haemolytica, and Helicobacter felis) were enriched in treatment IV. Correlation analysis revealed that the intestinal development index positively correlated with the relative abundance of cecal mucosal microbiota and the amount of digested fiber. These results indicated that increased proportions of fiber-degrading microbes and enhanced intestinal development jointly promote the host to digest an appropriate high-fiber diet. However, although too-high fiber levels in diet could maintain the adaptive development of cecal epithelium, the proportions of pathogenic bacteria increased, which might lead to a decrease of fiber digestion in pigs. IMPORTANCE Although studies about the effects of dietary fiber on fiber digestion and intestinal microbiota of pigs were widely in progress, few studies have been conducted on the dynamic response of intestinal microbiota to dietary fiber levels, and the characteristics of intestinal microbiota and intestinal epithelial development adapted to high-fiber diet s were still unclear. Appropriate high fiber promoted the thickness of large intestine wall, increased the density of cecal goblet cells, and promoted the renewal of cecal epithelial cells. In addition, appropriate high fiber improves the microbial abundance with fiber-digesting potential. However, excessive dietary fiber caused an increase in the abundance of pathogenic bacteria. These results indicated that an increased proportion of fiber-degrading microbes and enhanced intestinal development jointly promote host to digest appropriate high-fiber diets. However, although too-high fiber levels in diet could maintain the adaptive development of cecal epithelium, the proportions of pathogenic bacteria increased, which might lead to a decrease of fiber digestion in pigs. Our data provided a theoretical basis for rational and efficient utilization of unconventional feed resources in pig production.

Ontogenetic characteristics of the intestinal microbiota of Quasipaa spinosa revealed by 16S rRNA gene sequencing.

To analyse the correlation between the intestinal microbiota (IM) and differential development of Quasipaa spinosa across different stages of metamorphosis, we focused on four key developmental periods (15 days post-hatch [dph; Gosner stage, GS23], 60 dph [GS25], 90 dph [GS41] and 150 dph [GS25, GS41, GS42, GS46]) and used 16S rDNA amplicon sequencing. Results showed that IM diversity in Q. spinosa was related to life history. Specifically, there was a significant difference between the aquatic and terrestrial stages, and IM diversity increased with age. Proteobacteria, Bacteroidetes and Firmicutes were the dominant phyla in tadpoles, whereas Bacteroidetes, Proteobacteria, Firmicutes and Fusobacteria were the dominant phyla at the metamorphosis stages. The composition of the IM at different stages and ages varied considerably, but the changes were not substantial among different development stages at 150 dph. This was probably because age has a greater influence than growth factors, and host selective pressure increases with age. This study provides a theoretical reference for subsequent studies on the IM, as well as for the prevention of amphibian endogenous pathogenic microbial diseases.

Feed Safety and the Development of Poultry Intestinal Microbiota.

Simple SummaryIntensive gut colonisation of animals starts immediately after birth or hatch. Oral route of colonisation, and consequently the first feed, plays a significant role in the continual defining of the intestinal microbial community. The feed can influence colonisation in two ways: providing the microbial inoculum and providing the nutritional requirements that suit a specific type of microbes. In combination with environmental factors, feed shapes animal’s future health and performance from the first day of life. The objective of this review was to investigate feed safety aspects of animal nutrition from the gut colonisation aspect.The first feed offered to young chicks is likely the most important meal in their life. The complex gut colonisation process is determined with early exposure and during the first days of life before the microbial community is formed. Therefore, providing access to high-quality feed and an environment enriched in the beneficial and deprived of pathogenic microorganisms during this period is critical. Feed often carries a complex microbial community that can contain major poultry pathogens and a range of chemical contaminants such as heavy metals, mycotoxins, pesticides and herbicides, which, although present in minute amounts, can have a profound effect on the development of the microbial community and have a permanent effect on bird’s overall health and performance. The magnitude of their interference with gut colonisation in livestock is yet to be determined. Here, we present the animal feed quality issues that can significantly influence the microbial community development, thus severely affecting the bird’s health and performance.

Development and role of intestinal microbiota in term and preterm newborn babies. Accent on breast feeding

Intestinal microbiota (IM) plays in human organism a number of various functions including a participation in metabolic procecces, stimulation of immune function, competition with pathogenic flora, fermentation activity in colon. Microbial colonization of sterile gastrointestinal tract of newborn is based on several natural principles and depends on mode of delivery, vaginal and fecal flora of own mother, external factors (hospitalization, antibiotic therapy), and as well is regulated by breast feeding or bottle feeding. Besides that there is a proven difference between term and preterm newborn babies. Microbial community (so called Microbiome) of human milk with its complicated microbial society plays a key role in IM development, especially in combination with human milk oligosaccharides evolutionary connected with human intestinal microbiota development.

Effect of antibiotics in the first week of life on faecal microbiota development

BackgroundInfants are frequently exposed to antibiotics (AB) in the first week of life for suspected bacterial infections. Little is known about the effect of AB on the developing intestinal microbiota....

Therapeutic Interventions of Gut-Brain Axis as Novel Strategies for Treatment of Alcohol Use Disorder Associated Cognitive and Mood Dysfunction.

Alcohol use disorders (AUD) is characterized by persistent or intermittent alcohol cravings and compulsive drinking. The functional changes in the central nervous system (CNS) after alcohol consumption are alcohol-associated cognitive impairment and mood disorders, which are major health issues reported in AUDs. Studies have shown that transferring the intestinal microbiota from AUDs patients to germ-free animals causes learning and memory dysfunction, depression and anxiety-like behavior, indicating the vital role of intestinal microbiota in development of neuropsychiatric disorders in AUD. Intestinal flora composition of AUD patients are significantly different from normal people, suggesting that intestinal flora imbalance orchestrate the development of neuropsychiatric disorders in AUD. Studies suggests that gut microbiome links bidirectional signaling network of the enteric nervous system (ENS) to central nervous system (CNS), forming gut-microbe-brain axis (brain-gut axis). In this review, we discussed pathogenesis and possible treatment of AUD-induced cognitive deficits, anxiety, and depression disorders. Further, we described the mechanism of intestinal flora imbalance and dysfunction of hippocampus-amygdala-frontal cortex (gut-limbic circuit system dysfunction). Therefore, we postulate therapeutic interventions of gut-brain axis as novel strategies for treatment of AUD-induced neuropsychiatric disorders.

Developmental changes of nutrient digestion in young lambs are influenced by weaning and associated with intestinal microbiota

Understanding the effects of weaning on the changes of digestive function could help to design efficient intervention strategies for promoting the development of the lamb during the early stages of life. In this study, 24 lambs were divided into two groups (control group, lambs were not weaned; and weaning group, lambs were weaned at 21 days of age). The growth, nutrient digestion, gastrointestinal enzyme activity, plasma biochemical indicators, and intestinal microbiota at 7–49 days were determined, as well as the impact of early weaning. The nutrient digestion changed rapidly with age, especially at 14–28 days (p < 0.05). Weaning reduced the dry matter (DM), crude protein (CP), and ether extract (EE) intake and digestion, but increased the starch, neutral detergent fiber (NDF), and acid detergent fiber (ADF) intake and digestion (p < 0.05). Weaning did not affect the overall jejunal microbiota (p > 0.05), but affected the relative abundance of certain bacteria taxa (p < 0.05). Lactic acid-producing bacteria, such as Olsenella, Bacillus, Sharpea, and Bifidobacterium are closely related to CP or EE digestion and growth performance (p < 0.05). In summary, we delineated the pattern of nutrient digestion and intestinal microbiota development in young lambs, and the impact of early weaning.