Holstein and Jersey Steers Differ in Rumen Microbiota and Enteric Methane Emissions Even Fed the Same Total Mixed Ration

Abstract

Previous studies have focused on the rumen microbiome and enteric methane (CH4) emissions in dairy cows, yet little is known about steers, especially steers of dairy breeds. In the present study, we comparatively examined the rumen microbiota, fermentation characteristics, and CH4 emissions from six non-cannulated Holstein (710.33 ± 43.02 kg) and six Jersey (559.67 ± 32.72 kg) steers. The steers were fed the same total mixed ration (TMR) for 30 days. After 25 days of adaptation to the diet, CH4 emissions were measured using GreenFeed for three consecutive days, and rumen fluid samples were collected on last day using stomach tubing before feeding (0 h) and 6 h after feeding. CH4 production (g/d/animal), CH4 yield (g/kg DMI), and CH4 intensity (g/kg BW0.75) were higher in the Jersey steers than in the Holstein steers. The lowest pH value was recorded at 6 h after feeding. The Jersey steers had lower rumen pH and a higher concentration of ammonia-nitrogen (NH3-N). The Jersey steers had a numerically higher molar proportion of acetate than the Holstein steers, but the opposite was true for that of propionate. Metataxonomic analysis of the rumen microbiota showed that the two breeds had similar species richness, Shannon, and inverse Simpson diversity indexes. Principal coordinates analysis showed that the overall rumen microbiota was different between the two breeds. Both breeds were dominated by Prevotella ruminicola, and its highest relative abundance was observed 6 h after feeding. The genera Ethanoligenens, Succinivibrio, and the species Ethanoligenens harbinense, Succinivibrio dextrinosolvens, Prevotella micans, Prevotella copri, Prevotella oris, Prevotella baroniae, and Treponema succinifaciens were more abundant in Holstein steers while the genera Capnocytophaga, Lachnoclostridium, Barnesiella, Oscillibacter, Galbibacter, and the species Capnocytophaga cynodegmi, Galbibacter mesophilus, Barnesiella intestinihominis, Prevotella shahii, and Oscillibacter ruminantium in the Jersey steers. The Jersey steers were dominated by Methanobrevibacter millerae while the Holstein steers by Methanobrevibacter olleyae. The overall results suggest that sampling hour has little influence on the rumen microbiota; however, breeds of steers can affect the assemblage of the rumen microbiota and different mitigation strategies may be needed to effectively manipulate the rumen microbiota and mitigate enteric CH4 emissions from these steers.

Influence of dietary organic trace minerals on enteric methane emissions and rumen microbiota of heat-stressed dairy steers

“…VFA production is negatively correlated with ruminal pH [44]. In this study, the ruminal pH and total VFA were not influenced by trace mineral supplementation; however, lower ruminal pH was recorded in Jersey steers than in Holstein steers, which is in agreement with the findings of Islam et al [45]. This might be due to the higher total VFA production by Jersey steers compared to that by Holstein steers in this study.…”

Dietary forage to concentrate ratios impact on yak ruminal microbiota and metabolites

“…It is possible that the rumen microbiota was disturbed due to the feeding of high concentrate ( Krause and Oetzel, 2006 ; Moya et al, 2009 ), the rumen microbiota underwent value-added, together with the composition of the diet and the special breed of yaks, this resulted in a higher abundance and diversity of rumen microbiota in the C80 group of yaks. PCoA analysis showed that rumen microbiota clustered according to different dietary concentrate ratios and significant differences between rumen microbiota were observed, which is consistent with other studies ( Hu et al, 2019 ; Islam et al, 2021 ).…”

Effects of high concentrate rations on ruminal fermentation and microbiota of yaks

“…This suggests that feeding high concentrate diets to yaks causes a decrease in rumen pH and inhibition of cellulose-degrading bacteria, leading to a decrease in the diversity and abundance of ruminal bacteria. PCoA analysis showed that rumen microbial communities aggregated according to the concentrate ratio in diets, and significant differences between intra-ruminal microbial communities were observed, which were consistent with previous reports ( Hu et al, 2019 ; Islam et al, 2021 ).…”