Establishing populations of Megasphaera elsdenii YE 34 and Butyrivibrio fibrisolvens YE 44 in the rumen of cattle fed high grain diets

Abstract

Aim: To determine whether Megasphaera elsdenii YE34 (lactic acid degrader) and Butyrivibrio fibrisolvens YE44 (alternative starch utilizer to Streptococcus bovis) establish viable populations in the rumen of beef cattle rapidly changed from a forage-based to a grain-based diet. Methods and Results: Five steers were inoculated with the two bacterial strains (YE34 and YE44) and five served as uninoculated controls. With the exception of one animal in the control group, which developed acidosis, all steers rapidly adapted to the grain-based diet without signs of acidosis (pH decline and accumulation of lactic acid). Bacterial populations of S. bovis, B. fibrisolvens and M. elsdenii were enumerated using real-time Taq nuclease assays. Populations of S. bovis remained constant (except in the acidotic animal) at ca 10 7 cell equivalents (CE) ml )1 throughout the study. Megasphaera elsdenii YE34, was not detectable in animals without grain in the diet, but immediately established in inoculated animals, at 10 6 CE ml )1 , and increased 100-fold in the first 4 days following inoculation. Butyrivibrio fibrisolvens, initially present at 10 8 CE ml )1 , declined rapidly with the introduction of grain into the diet and was not detectable 8 days after grain introduction. Conclusion: Megasphaera elsdenii rapidly establishes a lactic acid-utilizing bacterial population in the rumen of grain-fed cattle 7-10 days earlier than in uninoculated cattle. Significance and Impact of the Study: The study has demonstrated that rumen bacterial populations, and in particular the establishment of bacteria inoculated into the rumen for probiotic use, can be monitored by real-time PCR.

Performance, ruminal changes, behaviour and welfare of growing heifers fed a concentrate diet with or without barley straw

“…No changes in S. bovis and M. elsdenii quantifications due to the treatments were detected, although we observed that M. elsdenii levels were numerically higher than S. bovis levels. These results agree with other authors who observed that enumeration of S. bovis was stable and in low numbers in the rumen of adapted high-grain cattle, except when animals are unadapted to grain or during a rapid transition when there could be a high increase of this bacteria (Olumeyan et al, 1986;Klieve et al, 2003;Nagaraja and Titgemeyer, 2007). Moreover, it is well reported that M. elsdenii is abundant in animals adapted to high grain and it is either not detected or detected in low numbers in animals receiving 100% forage diets (Klieve et al, 2003;Krause et al, 2003;Brown et al, 2006).…”

Production of trans C18:1 and conjugated linoleic acid in continuous culture fermenters fed diets containing fish oil and sunflower oil with decreasing levels of forage

“…High concentrate diets have been shown to promote the growth of Megasphera elsdenii YJ-4 which can convert linoleic acid to t10c12 CLA (Kim et al, 2002). Furthermore, feeding high grain diets to steers has been shown to stimulate the growth of the YE34 strain of Megasphera elsdenii and cause a rapid decline in Butyrivibrio fibrisolvens YE44 (Klieve et al, 2003) and its is well established that VA is an intermediate of linoleic acid metabolism by isolates of Butyrivibrio fibrisolvens (Harfoot & Hazlewood, 1988).…”

Effect of silage type and concentrate level on conjugated linoleic acids, trans-C18:1 isomers and fat content in milk from dairy cows

“…3c). High grain diets promote the growth of the bacterial strain Megasphera elsdenii YJ-4 [18] due to a decrease in rumen pH and cause a rapid decline in the main cellulose digesting bacteria Butyrivibrio fibrisolvens [19]. Megasphera elsdenii YJ-4 exhibits cis9,trans10-isomerase activity [20], which can convert 18:2n-6 to trans10,cis12-CLA and trans10-C18:1, whereas Butyrivibrio fibrisolvens produces cis9,trans11-CLA and trans11-C18:1 as intermediates in the hydrogenation of 18:2n-6 [21].…”