RAW MILK MICROBIOLOGICAL CONTAMINANTS AND ITS SOURCES IN FARM ENVIRONMENT

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RAW MILK MICROBIOLOGICAL CONTAMINANTS AND ITS
SOURCES IN FARM ENVIRONMENT
BALTFOODQUAL

• Konosonoka I.H., Jemeljanovs A., Ikauniece D.
• Research Institute of Biotechnology and
  Veterinary Medicine Sigra, Latvia

International Workshop Microbiological indices in
the whole cycle of animal origin food production
chain September 1718, 2009, Rakvere, Estonia
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INTRODUCTION

• Milk - the part of the healthy human diet
• Dairy foods provide a unique mix of nutrients
• Milk - an excellent medium for bacteria, yeasts
  and moulds

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Sources of milk contaminants

• Environmental saprophytic microorganisms from
  teat canal, teat and udder skin, dust, manure,
  bedding material, feed, water, milking system,
  cooling tanks

• Pathogenic microorganisms from diseased cows
  80 of inflamed quarter milk samples contain
  pathogenic bacteria

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Mastitis causing organisms

• Environmental pathogens
• Escherichia coli, Klebsiella pneumonia,
  Klebsiella oxytoca, Enterobacter aerogenes,
  Streptococcus uberis, Streptococcus dysgalactiae

• Contagious pathogens- Streptococcus agalactiae,
  Staphylococcus aureus,
• Mycoplasma spp.

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AIM OF THE STUDY

• to find out raw milk contaminants and its
• sources in farm environment

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MATERIAL AND METHODS - I

• In total
• 159 bulk milk samples
• 21 water samples
• 5 manure samples from the four dairy farms were
  analyzed
• 4 air samples from 2 farms
• 311 subclinical and 87 clinical mastitis
  secretion samples

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MATERIAL AND METHODS - II

• Cows were Latvian Brown (LB), Holsteins
• Black (HM), and crosses LBHM.
• Majority of cows (82,6 ) were from 1st to
• 4th lactation
• productivity of 63.0 of cows made 4 500 to
  6 000 kg of milk per year.

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Methods of analyses

• Bacteriological examination according to
  generally accepted standards
• Total bacterial count LVS EN ISO 48332003
• Salmonella spp. LVS EN ISO 65792003
• Listeria monocytogenes LVS EN ISO 11290-1 A1
  2007
• Staphylococcus spp. LVS EN ISO 6888-11999

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RESULTS
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Microflora of bulk milk samples I
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Microflora of bulk milk samples II
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Microflora of bulk milk samples III
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Microflora of bulk milk samples IV

• Gram-negative microorganisms 9,4 ( n 159),
  int.al.
• Pantoea agglomerans,
• Escherichia coli,
• Hafnia alvei,
• Enterobacter cloacae,
• Pseudomonas aeruginosa,
• Aeromonas hydrophila,
• Serratia mercescens

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Microflora of subclinical secretion sample
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Microflora of clinical secretion samples
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Incidence of contaminated water samples () I
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Incidence of contaminated water samples () II
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Microflora from air in dairy farms
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Microflora from cows manure (n5)
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CONCLUSIONS I

• Food born pathogens Bacillus cereus,
  Staphylococcus aureus and Listeria monocytogenes
  were isolated from 15,7 , 1,2 , 0,6 bulk milk
  samples, respectively.
• Salmonella spp. had not been isolated from milk
  samples.
• Subclinically and clinically diseased cows milk
  is the source for raw milk contamination with
  Staphylococcus spp., Streptococcus spp. and gram-
  negative bacteria.

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CONCLUSIONS II

• Water used in dairy farms is the source for raw
  milk contamination with Escherichia coli,
  Enterococcus spp., Bacillus cereus, Clostridium
  spp. and coliform bacteria.
• Air in dairy farms may be source of contamination
  with members of Staphylococcus genus.
• Manure is the potential source for raw milk
  contamination with Bacillus cereus, Listeria
  spp., Escherichia coli.

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THANK YOU FOR YOURATTENTION!