Hygienic status of camel milk in Dubai (United Arab Emirates) under two different milking management systems [Elektronische Ressource] / by Valérie Eberlein

Valérie Eberlein

Informations

• Publié par: ludwig-maximilians-universitat_munchen
• Publié le: 01 janvier 2007
• Nombre de lectures: 61

Extrait

Central Veterinary Research Laboratory
Dubai (United Arab Emirates)
Scientific Director: Priv. Doz. Dr. Dr. habil. U. Wernery
presented through
Institut für Hygiene und Technologie der
Lebensmittel tierischen Ursprungs
(Lehrstuhl Prof. Dr. E. Märtlbauer)
der Tierärztlichen Fakultät der Universität München
Hygienic status of camel milk in Dubai (United Arab Emirates) under two different
milking management systems
Thesis for the attainment of the title of
Doctor in Veterinary Medicine
from the Veterinary Faculty
Ludwig-Maximilians-Universität München
by
Valérie Eberlein
Fontainebleau
München 2007
IAus dem Central Veterinary Research Laboratory
Dubai (United Arab Emirates)
Scientific Director: Priv. Doz. Dr. Dr. habil. U. Wernery
eingereicht über das
Institut für Hygiene und Technologie der
Lebensmittel tierischen Ursprungs
(Lehrstuhl Prof. Dr. E. Märtlbauer)
der Tierärztlichen Fakultät der Universität München
Hygienischer Status von Kamelmilch in Dubai (Vereinigte Arabische Emirate) unter
Berücksichtigung zweier verschiedener Milchgewinnungssysteme
Inaugural-Dissertation zur Erlangung
der tiermedizinischen Doktorwürde
der Tierärztlichen Fakultät
der Ludwig-Maximilians-Universität München
von
Valérie Eberlein
Fontainebleau
München 2007
IIGedruckt mit der Genehmigung der Tierärztlichen Fakultät der
Ludwig-Maximilians-Universität München
Dekan: Univ.-Prof. Dr. E. P. Märtlbauer
Referent: Univ.-Prof. Dr. Märtlbauer
Korreferent: Dr. Mansfeld
Tag der Promotion: 20. Juli 2007
IIITo my family
and to my friends who supported
me during the last years
IVTABLE OF CONTENT
TABLE OF CONTENT ..............................................................................................................I
ABBREVIATIONS..................................................................................................................VI
1. INTRODUCTION......................................................................................................... - 1 -
2. LITERATURE REVIEW.............................................................................................. - 2 -
2.1 Dromedaries as milking animals........................................................................... - 2 -
2.1.1 Taxonomy and breeds ................................................................................... - 2 -
2.1.2 Physiology of reproduction in dromedary camels......................................... - 3 -
2.1.3 Camel population in the world...................................................................... - 4 -
2.1.4 Importance of the camel today and in the past.............................................. - 5 -
2.1.4.1 Food and other products............................................................................ - 6 -
2.1.4.1.1 Milk and milk products ....................................................................... - 6 -
2.1.4.1.2 Meat and meat products - 8 -
2.1.4.1.3 Other products..................................................................................... - 8 -
2.1.5 Infectious diseases of food safety importance............................................... - 8 -
2.1.5.1 Zoonoses.................................................................................................... - 8 -
2.1.5.2 Foot-and-mouth disease (FMD).............................................................. - 11 -
2.2 Characteristics of lactation and camel milk ........................................................ - 11 -
2.2.1 Anatomy of the camel udder ....................................................................... - 11 -
2.2.2 Characteristics of camel milk...................................................................... - 12 -
2.2.3 Lactation...................................................................................................... - 12 -
2.2.4 Milk yield .................................................................................................... - 12 -
2.2.5 Milk contents and pH .................................................................................. - 14 -
2.3 Bacteria in camel milk......................................................................................... - 16 -
2.3.1 Total bacteria count (TBC) ......................................................................... - 18 -
2.3.2 Staphylococci .............................................................................................. - 18 -
2.3.2.1 Coagulase positive staphylococci (CPS)................................................. - 20 -
2.3.2.2 Coagulase negative staphylococci (CNS) ............................................... - 21 -
2.3.3 Coliforms and Escherichia coli................................................................... - 21 -
2.3.3.1 Escherichia coli....................................................................................... - 21 -
I2.3.3.2 Coliforms................................................................................................. - 22 -
2.3.3.3 Verotoxinogenic Escherichia coli (VTEC)............................................. - 23 -
2.3.4 Bacillus cereus ............................................................................................ - 24 -
2.3.5 Salmonella spp. ........................................................................................... - 24 -
2.3.6 Listeria spp.................................................................................................. - 25 -
2.3.7 Other bacteria .............................................................................................. - 25 -
2.3.7.1 Streptococcus spp.................................................................................... - 25 -
2.3.7.2 Further bacteria ....................................................................................... - 27 -
2.3.8 Yeasts .......................................................................................................... - 29 -
2.4 Further diagnostic means in camel milk ............................................................. - 29 -
2.4.1 Somatic cells and cell fragments in camel milk.......................................... - 29 -
2.4.1.1 Semi-quantitative California mastitis test (CMT)................................... - 30 -
2.4.1.2 Somatic cell count (SCC)........................................................................ - 31 -
2.4.2 Electrical conductivity in cow and camel milk ........................................... - 32 -
2.4.3 N-acetyl-ß-D-Glucosaminidase (NAGase) ................................................. - 33 -
2.4.4 Indicator enzymes for heat treatment of milk ............................................. - 34 -
3. OWN INVESTIGATIONS ......................................................................................... - 35 -
3.1 Materials..............................................................................................................- 35 -
3.1.1 Animals ....................................................................................................... - 35 -
3.1.2 Samples - 35 -
3.1.3 Milking........................................................................................................ - 36 -
3.1.3.1. Machine milking ................................................................................. - 36 -
3.1.3.2. Hand Milking ...................................................................................... - 37 -
3.1.4 Sampling...................................................................................................... - 37 -
3.1.5 Examination scheme ................................................................................... - 37 -
3.1.6 Bacteria in camel milk - culture media and reagents .................................. - 38 -
3.1.6.1. Preparation of samples and dilutions .................................................. - 38 -
3.1.6.2. Total bacterial count (TBC) ................................................................ - 38 -
3.1.6.3. Coagulase positive staphylococci (CPS)............................................. - 38 -
3.1.6.4. Coliforms and Escherichia coli........................................................... - 38 -
3.1.6.5. Verotoxinogenic (VTEC) in faecal samples ............ - 38 -
3.1.6.6. Bacillus cereus .................................................................................... - 39 -
3.1.6.7. Salmonella spp. ................................................................................... - 39 -
II3.1.6.8. Listeria spp.......................................................................................... - 39 -
3.1.6.9. Other bacteria ...................................................................................... - 40 -
3.1.7 Somatic cells and cell fragments in camel milk.......................................... - 40 -
3.1.7.1. Semi-quantitative California mastitis test (CMT)............................... - 40 -
3.1.7.2. Somatic cell count (SCC).................................................................... - 40 -
3.1.8 Electrical conductivity................................................................................. - 41 -
3.1.9 I