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Field Collection and Sampling. Starting your collection. What to sample: Tissue What to consider: Age, Season What methodology to used for your biological questions What is the natural h istory of your organism eg . Life history etc. - PowerPoint PPT Presentation
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Field Collection and Sampling
1courtesy of Carol Ritland
Starting your collection• What to sample: Tissue
• What to consider: Age, Season
• What methodology to used for your biological questions
• What is the natural
history of your organism
eg. Life history etc.http://images.google.ca/imgres?imgurl=http://www.christiananswers.net/kids/animals6.jpg&imgrefurl=http://www.christiananswers.net/kids/find2.html&h=375&w=500&sz=70&hl=en&start=5&usg=__d6sSz-0SC0vP_NuogTY5sRsvsxY=&tbnid=a9-2ftNtkcqeBM:&tbnh=98&tbnw=130&prev=/images%3Fq%3Danimals%26gbv%3D2%26hl%3Den%26client%3Dfirefox-a%26rls%3Dorg.mozilla:en-US:official%26sa%3DG
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Starting your collection….cont’d
• Check for permission and necessary permits for sampling
• Check for location of field sites
• Check on logistics of field collection
http://www.monkeygrove.com/scribbles/2002/PaperWork.gif3
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Conifer abundance: affect on soil richness
Photos = L. Ritlandcourtesy of Carol Ritland
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Starfish abundance: affect on barnacles
Photos = L. Ritland
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1) What should you collect?
2) What could you collect?
3) Where would you collect?
4) When would you collect?
5) How would you collect?
6) How much would you collect?
7) Why did you collect them?
Tissue (Always go fresh if possible):
– Plant: Seed, Leaves, Flower, Pollen, Bark, Xylem, Roots
–Animal: Reproductive tissue, muscle, skin, hair, scat, blood, ear/toe/tail clip, fin, tooth, sloughed skin, saliva
–Fungal: Hyphae, spores, fruiting bodies
–Bacterial: single isolate culture
–Destructive vs Non Destructive methods
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Factors to consider when collecting:
• Age:– Plant = actively growing material such as
apical points, seedlings– Animal = actively dividing tissue (buccal and
blood cells)– Fungus = young fruiting bodies (pure culture)– Bacteria = liquid culture
• Season:– For conifer = use early spring bud burst
especially for DNA markers8
How to sample:
• Sampling schemes:– Linear – Quadratic squares– Distance between samples – For animals: migration, reproductive
strategies, life cycle– For plants: clonality, roots, reproductive
strategies, life cycle– Consult a statistician? (Gene expression
studies)9courtesy of Carol Ritland
Sampling cont’d
• Tools for sampling:– Ideally flash freezing samples with liquid
nitrogen and transportation under ultra low temperature
– Clean and if possible sterilize collection tools between samples
– Pack samples with foil or proper containers eg. cryovials
– Label all samples with non water based ink and protect with clear tape/paper and pencil
10courtesy of Carol Ritland
Liquid nitrogen vapour tanks
11courtesy of Carol Ritland
Ultralow temp. Liq N2 tanks
•Pending on size•Ultralow temp can last from 10 days to 3 weeks•Can be used on aircrafts
12courtesy of Carol Ritland
Use sterile technique when
sampling
•Keep meticulous records•Identify any problems in the field for given sample•Do not depend on your memory alone
13courtesy of Carol Ritland
Long Term Storage:
– Ideally all tissues should be kept at ultra low temperature (minus 70 to 80°C)
– Certain tissues (blood, animal tissues cut into small pieces <1mm2 ) could be stored in 100% ethanol and saturated EDTA
– Plants (small amounts) could be desiccated with lots of silica beads with lots of changes of beads
14courtesy of Carol Ritland
No No..s
• Items to avoid:– Unnecessary chemicals eg. Formalin– historical samples that has been treated with
fixatives– degraded samples– freezing and thawing of tissue– freezer burn (improper storage conditions)– improper inventory of samples
15courtesy of Carol Ritland
More to ponder…..
• Items to consider:– For certain molecular marker (eg. AFLP,
microarray) use the same tissue type (developmental differences could cause error when genotyping)
– If possible collect all samples within a season over a same span of time (eg. For microarray analysis)
– Collect more samples than required for pilot study and lost of samples
16courtesy of Carol Ritland