The Experts below are selected from a list of 64449 Experts worldwide ranked by ideXlab platform

Isaac Omwenga - One of the best experts on this subject based on the ideXlab platform.

  • staphylococcus aureus enterotoxin genes detected in milk from various Livestock Species in northern pastoral region of kenya
    Food Control, 2019
    Co-Authors: Isaac Omwenga, Gabriel Oluga Aboge, E S Mitema, George Obiero, Catherine Ngaywa, Nicholas Ngwili, George Wamwere, Martin Wainaina
    Abstract:

    Abstract Staphylococcus aureus (SA) food poisoning results from consumption of preformed S. aureus enterotoxins in food. The enterotoxins are one of the most important virulence factors of the bacterium. The risk posed by contamination of milk intended for human consumption by pathogenic S. aureus in pastoral areas in Kenya is still generally not well documented yet this information is critical for ensuring safety to consumers who sometimes may take unpasteurized milk. This study, therefore determined the prevalence of S. aureus enterotoxin genes in raw milk from cattle, goats, sheep and camels intended for human consumption in northern Kenya. A total of 603 milk samples from 57 zebu cattle, 346 galla goats, 8 red Maasai and dorper sheep, 4 one-humped camel (Camelus dromedaries) and 188 pooled from all animals were collected from Isiolo and Marsabit counties of Kenya. S. aureus isolates were cultured from milk samples using a selective media, mannitol salt agar (MSA). Suspect colonies of SA were further analyzed using biochemical tests. Polymerase chain reaction and sequencing techniques were used to confirm SA and detect sea, seb, sec, sed and see enterotoxin genes. Overall, potentially pathogenic S. aureus harboring enterotoxic genes were detected in 85 (14.09%, 95% CI: 11.55–17.1%) of the total milk samples. Genes encoding enterotoxins were detected in the S. aureus bacteria isolated from the milk samples. At least one type of S. aureus enterotoxin gene (SE) was detected in 74.11% (95% CI: 63.91–82.24%) of the 85 isolates. The most frequently encountered gene in the two counties was see (51; 60%, 95% CI: 49.73–69.76%) followed by sea (22; 25.88%, 95% CI: 17.76–36.09%) and sec (19; 22.35%, 95% CI: 14.8–32.29%). None of the isolates tested positive for sed. Overall, 21 of the 85 (24.7%, 95% CI: 16.76–34.83%) strains harbored more than one enterotoxin gene. More than half of the S. aureus isolates harbored at least one of the enterotoxin coding genes, indicating milk samples contaminated by S. aureus could have a high chance of causing staphylococcal food intoxication. Consumption of raw and sour milk in the region could increase the risk of staphylococcal food poisoning and pastoral communities in the region are therefore advised to consume pasteurized milk.

Andredenis G Wright - One of the best experts on this subject based on the ideXlab platform.

  • analysis of rumen methanogen diversity in water buffaloes bubalus bubalis under three different diets
    Microbial Ecology, 2012
    Co-Authors: Raul Franzolin, Benoit Stpierre, Korinne S Northwood, Andredenis G Wright
    Abstract:

    The water buffalo (Bubalus bubalis) is a prominent Livestock Species for the production of milk and meat in many countries. We investigated the diversity of rumen methanogens in Mediterranean water buffaloes maintained in Brazil under different diets: corn silage, grazing pasture, or sugar cane. A total of 467 clones were isolated from three methanogen 16S rRNA gene clone libraries that each represented a distinct feed type. The 467 clones were assigned to 19 Species-level operational taxonomic units (OTUs). Four OTUs were represented in all three libraries, eight OTUs were library-specific, six OTUs were found in only the corn silage and pasture grazing libraries, and one OTU was shared only between pasture grazing and sugar cane libraries. We found that Methanobrevibacter-related sequences were the most abundant in the water buffaloes sampled for our analysis, in contrast to previously reported studies showing that Methanomicrobium mobile-like methanogens were the most abundant methanogens in water buffaloes of Murrah and Surti breeds sampled in India. Considering the worldwide distribution of water buffaloes and the likely wide variety of diets provided, our results combined with studies from other groups support that larger scope analyses of microbiomes for this Livestock Species would provide great insight into the contribution of geographical location, breed, and diet in determining the population structure of rumen microorganisms.

Martin Wainaina - One of the best experts on this subject based on the ideXlab platform.

  • staphylococcus aureus enterotoxin genes detected in milk from various Livestock Species in northern pastoral region of kenya
    Food Control, 2019
    Co-Authors: Isaac Omwenga, Gabriel Oluga Aboge, E S Mitema, George Obiero, Catherine Ngaywa, Nicholas Ngwili, George Wamwere, Martin Wainaina
    Abstract:

    Abstract Staphylococcus aureus (SA) food poisoning results from consumption of preformed S. aureus enterotoxins in food. The enterotoxins are one of the most important virulence factors of the bacterium. The risk posed by contamination of milk intended for human consumption by pathogenic S. aureus in pastoral areas in Kenya is still generally not well documented yet this information is critical for ensuring safety to consumers who sometimes may take unpasteurized milk. This study, therefore determined the prevalence of S. aureus enterotoxin genes in raw milk from cattle, goats, sheep and camels intended for human consumption in northern Kenya. A total of 603 milk samples from 57 zebu cattle, 346 galla goats, 8 red Maasai and dorper sheep, 4 one-humped camel (Camelus dromedaries) and 188 pooled from all animals were collected from Isiolo and Marsabit counties of Kenya. S. aureus isolates were cultured from milk samples using a selective media, mannitol salt agar (MSA). Suspect colonies of SA were further analyzed using biochemical tests. Polymerase chain reaction and sequencing techniques were used to confirm SA and detect sea, seb, sec, sed and see enterotoxin genes. Overall, potentially pathogenic S. aureus harboring enterotoxic genes were detected in 85 (14.09%, 95% CI: 11.55–17.1%) of the total milk samples. Genes encoding enterotoxins were detected in the S. aureus bacteria isolated from the milk samples. At least one type of S. aureus enterotoxin gene (SE) was detected in 74.11% (95% CI: 63.91–82.24%) of the 85 isolates. The most frequently encountered gene in the two counties was see (51; 60%, 95% CI: 49.73–69.76%) followed by sea (22; 25.88%, 95% CI: 17.76–36.09%) and sec (19; 22.35%, 95% CI: 14.8–32.29%). None of the isolates tested positive for sed. Overall, 21 of the 85 (24.7%, 95% CI: 16.76–34.83%) strains harbored more than one enterotoxin gene. More than half of the S. aureus isolates harbored at least one of the enterotoxin coding genes, indicating milk samples contaminated by S. aureus could have a high chance of causing staphylococcal food intoxication. Consumption of raw and sour milk in the region could increase the risk of staphylococcal food poisoning and pastoral communities in the region are therefore advised to consume pasteurized milk.

Catherine Ngaywa - One of the best experts on this subject based on the ideXlab platform.

  • staphylococcus aureus enterotoxin genes detected in milk from various Livestock Species in northern pastoral region of kenya
    Food Control, 2019
    Co-Authors: Isaac Omwenga, Gabriel Oluga Aboge, E S Mitema, George Obiero, Catherine Ngaywa, Nicholas Ngwili, George Wamwere, Martin Wainaina
    Abstract:

    Abstract Staphylococcus aureus (SA) food poisoning results from consumption of preformed S. aureus enterotoxins in food. The enterotoxins are one of the most important virulence factors of the bacterium. The risk posed by contamination of milk intended for human consumption by pathogenic S. aureus in pastoral areas in Kenya is still generally not well documented yet this information is critical for ensuring safety to consumers who sometimes may take unpasteurized milk. This study, therefore determined the prevalence of S. aureus enterotoxin genes in raw milk from cattle, goats, sheep and camels intended for human consumption in northern Kenya. A total of 603 milk samples from 57 zebu cattle, 346 galla goats, 8 red Maasai and dorper sheep, 4 one-humped camel (Camelus dromedaries) and 188 pooled from all animals were collected from Isiolo and Marsabit counties of Kenya. S. aureus isolates were cultured from milk samples using a selective media, mannitol salt agar (MSA). Suspect colonies of SA were further analyzed using biochemical tests. Polymerase chain reaction and sequencing techniques were used to confirm SA and detect sea, seb, sec, sed and see enterotoxin genes. Overall, potentially pathogenic S. aureus harboring enterotoxic genes were detected in 85 (14.09%, 95% CI: 11.55–17.1%) of the total milk samples. Genes encoding enterotoxins were detected in the S. aureus bacteria isolated from the milk samples. At least one type of S. aureus enterotoxin gene (SE) was detected in 74.11% (95% CI: 63.91–82.24%) of the 85 isolates. The most frequently encountered gene in the two counties was see (51; 60%, 95% CI: 49.73–69.76%) followed by sea (22; 25.88%, 95% CI: 17.76–36.09%) and sec (19; 22.35%, 95% CI: 14.8–32.29%). None of the isolates tested positive for sed. Overall, 21 of the 85 (24.7%, 95% CI: 16.76–34.83%) strains harbored more than one enterotoxin gene. More than half of the S. aureus isolates harbored at least one of the enterotoxin coding genes, indicating milk samples contaminated by S. aureus could have a high chance of causing staphylococcal food intoxication. Consumption of raw and sour milk in the region could increase the risk of staphylococcal food poisoning and pastoral communities in the region are therefore advised to consume pasteurized milk.

Raul Franzolin - One of the best experts on this subject based on the ideXlab platform.

  • analysis of rumen methanogen diversity in water buffaloes bubalus bubalis under three different diets
    Microbial Ecology, 2012
    Co-Authors: Raul Franzolin, Benoit Stpierre, Korinne S Northwood, Andredenis G Wright
    Abstract:

    The water buffalo (Bubalus bubalis) is a prominent Livestock Species for the production of milk and meat in many countries. We investigated the diversity of rumen methanogens in Mediterranean water buffaloes maintained in Brazil under different diets: corn silage, grazing pasture, or sugar cane. A total of 467 clones were isolated from three methanogen 16S rRNA gene clone libraries that each represented a distinct feed type. The 467 clones were assigned to 19 Species-level operational taxonomic units (OTUs). Four OTUs were represented in all three libraries, eight OTUs were library-specific, six OTUs were found in only the corn silage and pasture grazing libraries, and one OTU was shared only between pasture grazing and sugar cane libraries. We found that Methanobrevibacter-related sequences were the most abundant in the water buffaloes sampled for our analysis, in contrast to previously reported studies showing that Methanomicrobium mobile-like methanogens were the most abundant methanogens in water buffaloes of Murrah and Surti breeds sampled in India. Considering the worldwide distribution of water buffaloes and the likely wide variety of diets provided, our results combined with studies from other groups support that larger scope analyses of microbiomes for this Livestock Species would provide great insight into the contribution of geographical location, breed, and diet in determining the population structure of rumen microorganisms.