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| − | ==Blood samples==
| + | #REDIRECT[[:Category:Pathological Sample Collection]] |
| − | When collecting blood samples, fill tubes containing anticoagulant to the fill line and mix gently immediately after collection. Vacutainers can be used for large animal blood sample collection, and a needle and syringe for small animals. The jugular vein is the preferred collection site using a wide bore needle to prevent haemolysis of the blood from using excessive suction during collection. The cephalic and saphenous veins are alternative venipuncture sites. Ensure the venipuncture site is clean and swabbed, wear gloves and ensure you have adequate restraint prior to collecting a blood sample.
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| − | Always label your sample tubes with permanent marker immediately with the animal's details and the date and time of collection. Serum samples can be processed by allowing the blood to clot in an upright position and removing the serum from the tube prior to sending the sample for analysis to avoid haemolysis (bursting of the red blood cells into the serum) during transit. A more ideal method of serum separation is to centrifuge the sample -balance the centrifuge by adding a tube filled with the same volume of fluid in the opposite well in the centrifuge for safety.
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| − | The following table is a guide to the sample type required for some specific laboratory tests - seek guidance from your processing laboratory for confirmation of sample requirements, which can vary depending on the equipment used to analyse the sample.
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| − | {|border="2" width="800px" align="center" cellspacing="0" cellpadding="4" rules="all" style="margin:1em 1em 1em 0; border:solid 1px #AAAAAA; border-collapse:collapse;empty-cells:show"
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| − | !bgcolor="#A7C1F2" width="180px"|Test Required
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| − | !bgcolor="#A7C1F2"|Sample Required
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| − | !bgcolor="#A7C1F2"|Comments
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| − | !align="left" bgcolor="#F2F2F2"|Haematology
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| − | |bgcolor="#F2F2F2"|EDTA
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| − | |bgcolor="#F2F2F2"|Mix gently immediately after collection
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| − | !align="left"|Biochemistry
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| − | |Serum
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| − | |Centrifuge after permitting sufficient clotting time (min 2 hours)
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| − | |-
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| − | !align="left"|Fibrinogen
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| − | |Citrate
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| − | |Mix gently immediately after collection
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| − | |-
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| − | !align="left" bgcolor="#F2F2F2"|SAA
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| − | |bgcolor="#F2F2F2"|Serum
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| − | |bgcolor="#F2F2F2"|Needs to be processed quickly as the half life is very short
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| − | !align="left" bgcolor="#F2F2F2"|Electrolytes
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| − | |bgcolor="#F2F2F2"|Heparin
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| − | |bgcolor="#F2F2F2"|Mix gently immediately after collection
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| − | |-
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| − | !align="left"|Glucose
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| − | |Fluoride oxalate
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| − | |Can use fresh whole blood if tested immediately
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| − | |-
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| − | !align="left" bgcolor="#F2F2F2"|Insulin
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| − | |bgcolor="#F2F2F2"|Serum
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| − | |bgcolor="#F2F2F2"|Fasting sample required
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| − | |-
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| − | !align="left"|Prothrombin clotting time
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| − | |Citrate
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| − | |A normal sample is required for comparison
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| − | |-
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| − | !align="left"|Progesterone
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| − | |Serum
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| − | |-
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| − | !align="left"|Oestrone Sulphate
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| − | |Serum
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| − | |-
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| − | !align="left" bgcolor="#F2F2F2"|Testosterone
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| − | |bgcolor="#F2F2F2"|Serum
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| − | |bgcolor="#F2F2F2"|Request Testosterone before Inhibin for GCTs
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| − | |-
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| − | !align="left" bgcolor="#F2F2F2"|IgG
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| − | |bgcolor="#F2F2F2"|Serum
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| − | |bgcolor="#F2F2F2"|Measurement techniques vary so check sample requirements
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| − | !align="left" bgcolor="#F2F2F2"|ACTH
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| − | |bgcolor="#F2F2F2"|EDTA plasma
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| − | |bgcolor="#F2F2F2"| Freeze plasma as soon after collection as poss (max 2 hours)
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| − | |-
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| − | !align="left" bgcolor="#F2F2F2"|Selenium
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| − | |bgcolor="#F2F2F2"|Heparin/Serum
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| − | |bgcolor="#F2F2F2"|Send Heparin for deficiency testing, serum for toxicity testing.
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| − | |-
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| − | !align="left"|Zinc
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| − | |Serum
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| − | |Avoid using tubes with a rubber bung
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| − | |-
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| − | !align="left" bgcolor="#F2F2F2"|Drugs testing
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| − | |bgcolor="#F2F2F2"|Serum or Heparin
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| − | |bgcolor="#F2F2F2"|Send to HFL
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| − | !align="left"|Virus Titres e.g. EHV
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| − | |Serum
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| − | |Take 2 samples 14 days apart (freeze 1st)
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| − | |-
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| − | !align="left"|Tapeworm ELISA
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| − | |Serum
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| − | |-
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| − | !align="left"|Fractional Excretion test
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| − | |Serum and urine
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| − | |Collect both samples simultaneously if possible and do not permit
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| − | food or fluids until both are collected
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| − | |-
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| − | |}
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| − | ==Bacteriology Samples==
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| − | ===Swabs===
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| − | *Swab the area which is showing active signs of inflammation - avoid areas of pus as the neutrophilic destruction of bacteria which forms pus is less likely to produce a live culture.
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| − | *Use aseptic techniques and watch the swab tip until it has been safely replaced in the swab container to prevent accidental contamination prior to culture.
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| − | *Transport media containing charcoal is suitable for most samples with some notable exceptions such as Strangles PCR swabs. Check with your submitting lad the first time you collect a swab for a specific diagnostic test to see if there are any special transport medium requirements. CEMO swabs must be taken in charcoal.
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| − | *Label the swab immediately and indelibly with the patient details, site, and date.
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| − | *Fill in your external lab request form as completely as possible - the more information you include the better the chances of a diagnostic result. Most cultures are likely to give a mixed growth and if the pathologist can rule in or out organism based on the information you give them then the pathological process becomes considerably more accurate.
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| − | *Refrigerate samples that are awaiting postage later in the day, as this will help to prevent an overgrowth of fast growing organisms at the expense of pathogenic organisms.
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| − | ===In House Culture===
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| − | Accurate paperwork is essential when culturing in house samples so that changes noted on plates can be recorded over time. Always warm culture plates to room temperature prior to inoculation or cold shock can inhibit a delicate organism from growing on a plate. Different mediums can be a used to select for an organism of interest:
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| − | #Blood Agar (BA) is the standard plate used for most samples - in most cases an additional plate is added to give more information about the identity of any organism that successfully grows.
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| − | #COBA is selective for Streptococci species, which are ubiquitous in some species and frequently cause opportunistic infections. Tracheal washes, joint samples, and cervical swabs and potential Strep equi cases require this medium in addition to BA.
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| − | #CLED with Andrade’s indicator is a useful medium when a swab is likely to grow E coli; the indicator will turn pink and the colonies have a distinctive look and smell.
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| − | #Sabaroud plates are selective for fungi and are useful for skin scrapes where Dermatophytes are suspected - for many fungi special incubation requirements (e.g. temperature settings of 30°C for 48 hours) must be met so check the requirement based on the most likely organism to culture.
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| − | #XLD and Brilliant green are used to encourage and identify Salmonella species; the colonies grow with specific characteristics on these two plates. Place your sample in Selenite broth prior to inoculating this media to reduce the number of contaminant organisms that will grow on the plate.
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| − | #MRSA Chromogenic media will give a rapid (18 hour) diagnosis of MRSA infection – growth of the organism is associated with a distinctive colour change.
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| − | #CEMO medium for Taylorella culture requires two plates of specialised agar which suppress the growth of contaminants; one plate contains added Streptomycin, the other is without Streptomycin as some strains of Taylorella have been found to be Streptomycin sensitive. | |
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| − | In addition to using these plates for your original innoculation, there are media available which can confirm the identity of an organism such as Pseudomonas aeruginosa that has growth on the standard media initially. Always test your growth media by maintaining known organisms and innoculating the media using normal conditions so that you can be sure that your methods are giving diagnostic results. Alternative methods of identifying an organism include biochemical tests such as oxidase or catalase reactions or latex agglutination tests.
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| − | ===Sensitivity testing===
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| − | Sensitivity testing requires a standardised approach to plate innocultion and disc strengths used - the British Society for Antimicrobial Chemotherapy (BSAC) guidelines publish a methology to ensure this. The plate requirement, dilution of the culture, the strength of antibiotic disc used, the interpretation of the disc size and the culture conditions are all specified in these guidelines, which ensures in vivo antiobiotic sensitivity. The remit is based on organism rather than species which the sampl originated from ,so it is a valid approach to ansure accurate sensitivity tests.
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| − | ==Skin Scrapes==
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| − | ==Urine Samples==
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| − | ==Peritoneal and Joint taps==
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| − | ==Tracheal Washes and BALs==
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| − | ==WECs==
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| − | ==Sending Samples by Post==
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| − | There are some absolute requirements for sending samples through the UK postal system. Blood samples cannot be posted outside the UK without an export license - use a large lab to send your sample as they will have the required licensing.
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| − | Packaging samples should follow the guidelines required by Royal Mail, namely:
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| − | *The maximum weight or volume permitted in any one package of diagnostic specimens is 50g/50ml. Samples that exceed this limit need to be packaged into several smaller packages rather than one large one.
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| − | *Use leak proof containers – seal the lid with a little parafilm or tape to ensure this. Label the sample accurately and in permanent ink including the sample type (e.g. blood, urine etc). Make sure samples preserved in Formalin are marked as such (in case of breakage during transport).
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| − | *Package the sample with sufficient tissue paper or cotton wool to absorb the entire contents of the sample should there be a leak whilst in transit. Always package bloods tubes/containers individually so they are kept separate from one another.
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| − | *Seal your wrapped sample in a separate outer packaging that is leak proof such as a sealable plastic bag.
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| − | *Place the sample and the lab request form into an envelope or jiffy bag that is clearly labeled in permanent ink ‘Diagnostic Specimen’.
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| − | *It is advisable (but not required) to add a returns address so that the practice can be contacted in the event of any problems.
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| − | [[Category:Blood Samples]] | |
| − | [[Category:WikiPath]]
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