Subclinical mastitis caused by Mycoplasma-like bacteria in in dairy cattle in South Australia

Transcription

1 Friday, August 12, 2016 Subclinical mastitis caused by Mycoplasma-like bacteria in in dairy cattle in South Australia Abd Al-Bar Al-Farha

2 Mycoplasma Smallest bacteria Mollicutes Cattle-associated M. bovis M. californicum M. bovigenitalium M. alkalescence M. bovoculi M. mycoides mycoides M. dispar Acholeplasma spp. Ureaplasma diversum Slide 1

3 Disorders in cattle3,4 Pneumonia Mastitis Arthritis Keratoconjuctivitis Otitis media Urogenital tract disorders Slide 2

4 Issues with Mycoplasma Slow growing bacteria Special culture requirements Not part of routine mastitis culture Do not grow on routine culture media Difficulties in survival

5 Mastitis Clinical: acute, subacute and chronic sub-clinical Mycoplasma mastitis, undifferentiated mastitis SCC Milk production

6 Economic impacts US= US$ 108 million annually Europe= US$ 130 million annually Slide 5

7 Aims Identify and isolate Mycoplasma species by microscopic culture method Examine the effects of Mycoplasma-like organisms compared to other mastitis pathogens on the test-day SCC and milk production Develop and compare between different PCR detection methods for Mycoplasma Evaluate the survival of Mycoplasma under different freezing conditions Slide 6

8 Materials and methods Source of isolates Single farm from Mt Gambier High SCC High rate of treatment failure Slide 7

9 Materials and methods Milk samples Cow level 2 occasions February 2015 September 2015 Slide 8

10 Total herd 2500 Sampled cows 368 Mycoplasma mastitis Other pathogens Slide 9

11 Materials and methods Enrichment Anaerobically for 5 days Culture Anaerobically 7-10 days Slide 10

12 Yeast extract Penicillin Peptones Thallium acetate Mycoplasma selective media

13 Molecular detection Development of PCR Mycoplasma in milk & culture samples Run all samples 2 Differentiate between Mycoplasma spp. 16S rrna gene sequencing Development of RT-PCR 1 Slide 12 3

14 Freezing Techniques

15 Results Slide 14

16 Culture & PCR results Slide 15

17 Mycoplasma colonies Typical fried egg appearance of colony of Mycoplasma-like organisms under the stereomicroscope (10 x magnification) Slide 16

18 Somatic cell counts SCC

19 Milk production

20 Survivability Results

21 Molecular results Conventional PCR Universal 16S rrna Positive sample -ve sample + control cpcr using Acholeplasma specific primer

22 Real time PCR Real Time PCR Quantification/DNA Binding Dye/DNA/Standard Curve ATCC for M. bovis Component Melt Data ATCC for M. bovis Positive sample Positive sample but different spp. Negative control

23 Sequencing n=16 9/16 M. bovis 7/16 Acholeplasma laidlawii

24 Conclusion Awareness for the importance of Mycoplasma mastitis Cornerstone for further research

25 Acknowledgments Supervisors Dr Kiro Petrovski Dr Farhid Hemmatzadeh Prof Darren Trott Farm owners and staff South East Vets Andrew Hoare

26 References 1- Aebi, M, Bodmer, M, Frey, J & pilo, p 2012, Herd specific strains of Mycoplasma bovis in outbreaks of Mycoplasma mastitis and pneumonia, Veterinary Microbiology, vol. 157, pp Amram, E, Freed M, Khateb, N, Miknla, I, Blum, S, Spergser, J, Sharir, B, Ozeri, R, Harrus, S & Lysnyansky, I. Year Multiple locus variable number tandem repeat analysis of Mycoplasma bovis isolated from local and imported cattle, The veterinary Journal, vol. 197, pp Boonyayatra, S, Fox, LK, Bosser, TE, Sawant, A, Gay, M & Raviv, Z 2012, A PCR assay and PCRrestriction fragment length polymorphism combination identifying the 3 primary Mycoplasma species causing mastitis, Journal of Dairy Science, vol. 95, pp Maunsell, FP, Woolums, AR, Francoz, D, Rosenbusch, RF, Step, DL, Wilson, DJ & Janzen, ED 2011, Mycoplasma bovis Infection in Cattle, Journal of Veterinary Internal Medicine, vol. 25, pp Morton, J Malmo, J, House, J & Mein, G 2014, Mycoplasma bovis in Australian dairy herds Australian Veterinary Journal, vol. 92, pp Zadoks, RN, Middleton, JR, McDougall, s, Katholm, J, Schukken, YH 2011, Molecular Epidemiology of Mastitis pathogens of Dairy Cattle and comparative & elevance to Humans, Journal of the Mammary Gland Biology and Neoplasia, vol. 01, No. 16, pp Boonyayatra, S., L. K. Fox, T. E. Besser, A. Sawant, and J. M. Gay Effects of storage methods on the recovery of Mycoplasma species from milk samples. Vet Microbiol 144(1-2): Nicholas, R. A. and R. D. Ayling Mycoplasma bovis: disease, diagnosis, and control. Res Vet Sci 74(2): Slide 25

27 Thanks