Differences in the Rumen Methanogen Populations of Lactating Jersey and Holstein Dairy Cows under the Same Diet Regimen

Abstract

In the dairy cattle industry, Holstein and Jersey are the breeds most commonly used for production. They differ in performance by various traits, such as body size, milk production, and milk composition. With increased concerns about the impact of agriculture on climate change, potential differences in other traits, such as methane emission, also need to be characterized further. Since methane is produced in the rumen by methanogenic archaea, we investigated whether the population structure of methanogen communities would differ between Holsteins and Jerseys. Breed-specific rumen methanogen 16S rRNA gene clone libraries were constructed from pooled PCR products obtained from lactating Holstein and Jersey cows, generating 180 and 185 clones, respectively. The combined 365 sequences were assigned to 55 species-level operational taxonomic units (OTUs). Twenty OTUs, representing 85% of the combined library sequences, were common to both breeds, while 23 OTUs (36 sequences) were found only in the Holstein library and 12 OTUs (18 sequences) were found only in the Jersey library, highlighting increased diversity in the Holstein library. Other differences included the observation that sequences with species-like sequence identity to Methanobrevibacter millerae were represented more highly in the Jersey breed, while Methanosphaera-related sequences and novel uncultured methanogen clones were more frequent in the Holstein library. In contrast, OTU sequences with species-level sequence identity to Methanobrevibacter ruminantium were represented similarly in both libraries. Since the sampled animals were from a single herd consisting of two breeds which were fed the same diet and maintained under the same environmental conditions, the differences we observed may be due to differences in host breed genetics.

Diversity of gut methanogens in herbivorous animals

“…The nature and representation of methanogens from the Skillman et al (2006) study show significant overlap with that of the Holsteins analyzed by Whitford et al (2001) presented above. In a recent report by King et al (2011), the frequency of M. ruminantium (33.3%) and unassigned St-Pierre and Wright Methanobrevibacter species (28.6%) in Jersey cows from a mixed herd were also found to be similar to the study by Skillman et al (2006), but in contrast M. millerae was identified as a prominent methanogen (34.6%) and unassigned species of Methanosphaera were observed at a much lower frequency.…”

“…Recently, rumen methanogens were investigated in lactating Holsteins from a mixed dairy herd (i.e. Holsteins and Jerseys) maintained under a TMR consisting of 33% forage, 33% corn silage and 33% concentrate (King et al, 2011), and although Methanobrevibacter was found to be the most prominent genus the population structure consisted of unassigned Methanobrevibacter species (47.8%), M. ruminantium (28.3%) and Methanobrevibacter millerae (16.7%). In another study, Hook et al (2011) studied the effects of changing the diet of non-lactating Holsteins from hay to a hay and mixed grain regimen.…”

Plant components with specific activities against rumen methanogens

“…Other data demonstrated predominance of only M. ruminantium (Leahy et al, 2010), whereas other data indicated the order Methanobacteriales as predominant in the rumen (Jarvis et al, 2000). However, the literature is still expanding and newer methanogens are being identified (Wright et al, 2008;Zhou et al, 2009;King et al, 2011;Lee et al, 2013).…”

Examination of the Rumen Bacteria and Methanogenic Archaea of Wild Impalas (Aepyceros melampus melampus) from Pongola, South Africa

“…However, Impala-3 was the only individual with no sequence reads in OTU 7 (Table 3). Furthermore, the Methanobrevibacter smithiigottschalkii-millerae-thaueri (SGMT) clade composed 81 % of the sequence reads from OTUs 1-8 while the Methanobrevibacter ruminantium-olleyae (RO) clade accounted for just 2 % [24]. …”