Characterization of bacterial populations recovered from the teat canals of lactating dairy and beef cattle by 16S rRNA gene sequence analysis

Abstract

Bovine mastitis is of major concern to the dairy industry worldwide. The bovine teat canal is the primary route through which pathogens enter the mammary gland. The microflora of the teat canals of dairy and beef cattle was investigated by analysis of 16S rRNA gene sequences. The goal was to examine the global difference between dairy cattle, which are sanitized on a regular basis, and beef cattle, which receive little sanitary management. A diverse population of 16S rRNA gene sequences was recovered from both the dairy and the beef herd samples, with diversity higher in the beef sample. Analysis revealed the presence of 90 operational taxonomic units (OTUs) among 156 sequences, with 45 OTUs in the dairy sample and 53 OTUs in the beef sample. Only eight OTUs were common to both samples. Members of the classes Clostridia and Bacilli dominated both samples, followed by Actinobacteria and Proteobacteria. The dairy sample contained a cluster (20/80 clones) of Staphylococcaceae members, seven of which were identifiable as coagulase-negative Staphylococcus species. The beef sample was dominated by members of the genus Clostridia, many of which have not been previously cultured. The results suggest that the microorganisms present in the bovine teat canal are more diverse than previously described.

Cow Teat Skin, a Potential Source of Diverse Microbial Populations for Cheese Production

“…Enterococcus faecium, Enterococcus hirae, Enterococcus lactis, Leuconostoc mesenteroides, Pediococcus pentosaceus, Streptococcus sp., and Streptococcus bovis identified on teat skin have also been identified in milk (7,8), suggesting that these species might be inoculated in milk by teat skin and not only by the teat canal (58). However, Lactococcus lactis (21,23,45), Streptococcus thermophilus, Streptococcus parauberis, and Streptococcus dysgalactiae (15,25,45), which have been identified in cow milk, have not been found on teat skin yet (58) or in the teat canal (26).…”

“…In the udder cells of healthy cows, milk is sterile; however, it is enriched with microorganisms during its passage through the teat canal (26) by contact with the surface of teat skin, the surrounding air, and other environmental factors on the farm (52). Housing conditions (bedding material, litter management) and milk house water supply can also influence the quality of the milk (27,29,43).…”

“…The teat cistern, teat canal, and teat apex can be colonized by a variety of microorganisms including pathogenic bacteria (26,47). The microbial population of the teat canal has been described by cloning and sequencing of 16S rRNA genes (26).…”

“…The microbial population of the teat canal has been described by cloning and sequencing of 16S rRNA genes (26). On the other hand, teat end (47) and teat skin microbial populations (58) have been described only by applying culture-based methods.…”

Biological Source Treatment of Acid Mine Drainage Using Microbial and Substrate Amendments: Microcosm Studies

“…The organism with the highest frequency (&19%) in this sample matched ''uncultured bacterium clone B-42'' in the NCBI Blast database. This organism appears to be related to cow teat canals and up-flow anaerobic sludge blanket reactors (Gill et al 2006;Purohit and Kapley 2005). Other species of note included an anaerobic bacterium (clone 159) associated with whey degradation (&1% of total Table 3).…”