Temporal profiling of rumen and hindgut microbiota revealed enterotypes affecting the microbial interactions and assembly in the gut of dairy cows.

It has been reported that rumen microbiota affects the cattle's milk-yield productivity, but the gut microbiota's contribution to the individualized performance and its associated mechanism have not been well defined. In this study, microbiota of 222 rumen and hindgut respective samples collected from 74 cows throughout the prepartum, postpartum, and peak-lactation periods were assessed using 16S rRNA gene amplicon analysis and were evaluated whether they affected inter-individual microbial interactions, assembly, functions, and contributed to host milk production and serum parameters. Prevotella-dominated (R-Prevot, n = 27) and Butyrivibrio-dominated (R-Butyri, n = 47) enterotypes were identified for rumen microbiota, and Prevotellaceae_UCG-003-dominated (H-Prevot, n = 33) and Paeniclostridium-dominated (H-Paenic, n = 41) enterotypes were identified for fecal microbiota.

Quantitative microbiome profiling reveals associations between ruminal microbiota shifts and accelerated milk production increase in dairy cows.

Milk is a valuable source of essential nutrients for humans. In dairy cows, the rumen-the largest digestive organ-plays a critical role in supporting high productivity. The postpartum period marks a crucial transition to peak lactation, characterized by a rapid rise in milk and milk solids yield.

High lignan- and flavonoid-based polyherbal mixtures improve performance in Holstein calves via modulating diarrhea frequency, rumen volatile fatty acid levels, and serum health parameters.

This study aimed to determine the effects of a polyherbal mixture (PM) containing 42.3% lignans and 21.2% flavonoids on the performance, ruminal fermentation, and serum biomarkers in preweaning Holstein calves.

Development and validation of a sensitive assay for analysis of D/L-serine in cells using ultra-high performance liquid chromatography-fluorescence detector.

The aim of this study was to establish a simple, sensitive, and robust ultra-high performance liquid chromatography coupled with fluorescence detection method (UPLC-FLD) for the determination of chiral D/L-serine in cells. D/L-serine in cells were derivatizated by o-phthalaldehyde (OPA) and N-acetyl-L-cysteine (NAC). Carbocisteine was selected as the internal standard.

Microbial diurnal rhythmicity in the rumen fluid impacted by feeding regimes and exogenous microbiome providing novel mechanisms regulating dynamics of the rumen microbiome.

Background: Diurnal oscillations have been reported on ruminal prokaryotes, but the daily rhythmicity of eukaryotes remains unknown. This study investigated diurnal oscillations of ruminal prokaryotes and eukaryotes under three different feeding managements and rumen fluid transplantation conditions, aiming to elucidate the regulatory mechanisms influencing the dynamic shifts of rumen microbiome through the daily feeding cycle.

Results: Quantification and profiling of the microbiota of 288 rumen samples collected from lactating dairy cows (n = 12) every 6-h over 48-h feeding cycles under ad libitum, restricted feeding at daytime and nighttime, respectively, revealed the rhythmicity in the population and abundance of ruminal bacteria, archaea, and protozoa.

Deterministic succession patterns in the rumen and fecal microbiome associate with host metabolic shifts in peripartum dairy cattle.

Background: Metabolic disorders in peripartum ruminants affect health and productivity, with gut microbiota playing a key role in host metabolism. Therefore, our study aimed to characterize the gut microbiota of peripartum dairy cows to better understand the relationship between metabolic phenotypes and the rumen and fecal microbiomes during the peripartum period.

Results: In a longitudinal study of 91 peripartum cows, we analyzed rumen and fecal microbiomes via 16S rRNA and metagenomic sequencing across six time points.

Temporal modulation of duodenal microbiota in dairy cows: effects of dietary shift from high forage to high concentration.

Introduction: The duodenum and its resident microbiota play crucial roles in the process of nutrient digestion and absorption. However, the temporal dynamics of duodenal microbiota in response to different dietary regimes remain are not yet fully understood. The aim of the present study was to explore the effects of high-forage (HF) and high-concentration (HS) diets on the circadian rhythm variation of duodenal fermentation and microbial communities in dairy cattle.

Diurnal shifts of rumen fermentation and microbial profiles revealed circadian rhythms of rumen bacteria, methanogens, and protozoa under high-grain and high-forage diets.

In this study, we investigated how the composition and population of rumen microbiota shifted in response to diurnal oscillations under 2 different diets (high grain vs. high forage). Five multiparous Holstein dairy cows with similar BW, DIM, and parity were enrolled in this study.

Competitive Analysis of Rumen and Hindgut Microbiota Composition and Fermentation Function in Diarrheic and Non-Diarrheic Postpartum Dairy Cows.

Postpartum dairy cows can develop nutritional diarrhea when their diet is abruptly changed for milk production. However, it is unclear whether nutritional diarrhea develops as a result of gut acidosis and/or dysbiosis. This study aimed to uncover changes in the gastrointestinal microbiota and its fermentation parameters in response to nutritional diarrhea in postpartum dairy cows.

Growth performance, blood metabolites, ruminal fermentation, and bacterial community in preweaning dairy calves fed corn silage-included starter and total mixed ration.

The objective of this study was to evaluate the effects of the inclusion of whole-plant corn silage (WPCS) in a starter or total mixed ration (TMR) on growth, blood metabolites, ruminal fermentation, and microbial community in preweaning dairy calves. A total of 45 healthy dairy calves were blocked by date of birth and randomly assigned to 1 of 3 treatments: 100% calf starter (CONS), a mix of 85% calf starter and 15% WPCS [dry matter (DM) basis; CSCS], or 100% WPCS-based lactation TMR (CTMR). Pasteurized normal milk was fed to all the animals under the same regimen.

Novel Process Methods for the Whole Cottonseed: Effect on the Digestibility, Productivity, Fat Profile, and Milk Gossypol Levels in Lactating Dairy Cows.

In this study, we aimed to determine the effect of mixed-process methods on the ruminal degradability of whole cottonseed (WCS) both and , and the effect on the production performance of dairy cows. Eight WCS process methods were tested on the ruminal digestibility, including crush-alkali 1 (CA1), crush-alkali 2 (CA2), crush-alkali 3 (CA3), alkali 1-crush (A1C), alkali 2-crush (A2C), alkali 3-crush (A3C), crush-only (CO), and non-processed. Alkali 1, 2, and 3 indicate the supplementation of alkali to WCS at the dose of 4% on dry matter (DM) base as followed: 4% NaOH, 2% NaOH + 2% CaO, and 2% NaOH + 2% CaCl alkaline, respectively.

Rumen Fermentation, Digestive Enzyme Activity, and Bacteria Composition between Pre-Weaning and Post-Weaning Dairy Calves.

To better understand the transition of rumen function during the weaning period in dairy calves, sixteen Holstein dairy calves were selected and divided into two groups: pre-weaning (age = 56 ± 7 day, = 8) and post-weaning (age = 80 ± 6 day, = 8). The rumen fluid was obtained by an oral gastric tube. The rumen fermentation profile, enzyme activity, bacteria composition, and their inter-relationship were investigated.

Adsorbents Reduce Aflatoxin M Residue in Milk of Healthy Dairy Cow Exposed to Moderate Level Aflatoxin B in Diet and Its Exposure Risk for Humans.

This study investigated the effect of moderate risk level (8 µg/kg) AFB in diet supplemented with or without adsorbents on lactation performance, serum parameters, milk AFM content of healthy lactating cows and the AFM residue exposure risk in different human age groups. Forty late healthy lactating Holstein cows (270 ± 22 d in milk; daily milk yield 21 ± 3.1 kg/d) were randomly assigned to four treatments: control diet without AFB and adsorbents (CON), CON with 8 μg/kg AFB (dry matter basis, AF), AF + 15 g/d adsorbent 1 (AD1), AF + 15 g/d adsorbent 2 (AD2).

Effects of Age, Diet CP, NDF, EE, and Starch on the Rumen Bacteria Community and Function in Dairy Cattle.

To understand the effects of diet and age on the rumen bacterial community and function, forty-eight dairy cattle at 1.5 (M1.5), 6 (M6), 9 (M9), 18 (M18), 23 (M23), and 27 (M27) months old were selected.

Effects of Rumen-Protected Niacin on Dry Matter Intake, Milk Production, Apparent Total Tract Digestibility, and Faecal Bacterial Community in Multiparous Holstein Dairy Cow during the Postpartum Period.

Extensive studies about rumen-protected niacin (RPN) supplementation on dairy cows in early-lactation have been done, but the effects of RPN on changes in dry matter intake (DMI), milk production, feed digestibility, and fecal bacterial community were conflicting. The aim of this study was to investigate them affected by RPN in postpartum cows. Multiparous Holstein dairy cows ( = 12, parity = 3.

Effects of Different Parts on the Chemical Composition, Silage Fermentation Profile, In Vitro and In Situ Digestibility of Paper Mulberry.

Paper mulberry (, PM) is high protein but unutilized as a feed source. The study explores the different parts (leaf, stem, and whole plant) of PM chemical composition, silage fermentation, and in vitro and in situ digestibility, aiming to give some guidelines to PM usage as feed. The result showed that the leaf had a higher fresh weight than the stem ( < 0.

The day-to-day stability of the ruminal and fecal microbiota in lactating dairy cows.

In this study, we examined differences between the microbiota of the ruminal fluid (DR) and feces (DF) from five lactating dairy cows over three consecutive days using 16S rRNA gene sequence-based analysis. Results showed significant differences between the microbial communities of the DR and DF. In particular, the relative abundance of the phyla Firmicutes and Actinobacteria was significantly lower (q < 0.

Effects of sulfanilamide on boar sperm quality, bacterial composition, and fertility during liquid storage at 17°C.

Sulfanilamide (SA) is an effective broad-spectrum antibacterial agent in human and veterinary medicine. The purpose of this study was to evaluate the effects of SA on boar sperm quality during liquid storage at 17°C and determine the optimal concentration of SA and its effects on bacterial growth, microbial composition, and maternal fertility. Boar ejaculates were diluted with a basic extender, containing different concentrations of SA, and stored in a 17°C incubator for 6 days.

The effects of different levels of superoxide dismutase in Modena on boar semen quality during liquid preservation at 17°C.

This study was conducted to investigate the influence of superoxide dismutase (SOD) on the quality of boar semen during liquid preservation at 17°C. Semen samples from 10 Duroc boars were collected and pooled, divided into five equal parts and diluted with Modena containing different concentrations (0, 100, 200, 300 and 400 U/mL) of SOD. During the process of liquid preservation at 17°C, sperm motility, acrosome integrity, membrane integrity, total antioxidant capacity (T-AOC) activity, malondialdehyde (MDA) content and hydrogen peroxide (H O ) content were measured and analyzed every 24 h.