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Collection, Preservation and Dispatch of Clinical Samples

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U. P. Veterinary University (DUVASU), Mathura
U. P. Veterinary University (DUVASU), Mathura

The presentation outlines the basic information for collection, labelling and dispatch of clinical samples

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Collection, Preservation and Dispatch of Clinical Samples 4/14/2021 1 Dr. Vinod Kumar Singh Department of Veterinary Microbiology DUVASU, Mathura
Need of Sample collection 4/14/2021 2 • Establishing a disease diagnosis • For Health Surveillance • For the Monitoring of Response to Treatment • For the Monitoring of Response to Vaccines • Aid in choosing the right choice of drug: ABST
Ensure before Sampling 4/14/2021 3 • What will I have to do? • What are the associated risks? • Personal safety Biosecurity • What do I need to do the job safely and securely?
4/14/2021 4 • Boots, gloves, overalls, eye-wear, face mask, first aid kit • Forms (Specimen Advice, key list) • Writing equipment, camera, phone • Disinfectant for instruments, containers, collection site and operators hands
4/14/2021 5 • Equipment and drugs for animal restraint • Equipment for animal identification • Equipment for clinical examination • Instruments for necropsy, biopsy, blood collection • Specimen packaging containers • Water
Keep a small kit ready 4/14/2021 6
Sample size 4/14/2021 7 S. No. Sample Size 1 Feces 10 gm 3. Organs/tissue 1-1.5 cm3 4. Blood 10 % of blood volume with fluid replacement
Sample Collection 4/14/2021 8 • Samples may be taken from • animals-dead or alive : intact carcass, tissues removed from carcasses, parasites, ingested food, feces, blood • their environment • consider personal safety and avoid injury or distress to the animal • Prior to collection note • the distribution • Color and morphological description • size and odor of the lesions
4/14/2021 9 • Every carcass be treated as a potential health hazard • Knowledge of pathogenesis of infectious disease • Separate samples for microscopic examination, microbiology, toxicology, and other analyses • Try to obtain a minimum of five specimens per species • Time of collection is also important in some cases
Sample Collection: live animal 4/14/2021 10 1.Blood • Ideally the skin at the site of vein puncture should be shaved (plucked) first and swabbed with 70 % ethyl alcohol • Taken by syringe and needle or by needle and vacuum tube • When taken from small veins it is better to use a syringe • For virology, antibiotics may be added • For samples with anti-coagulant and/ or antibiotics, thorough mixing is necessary
4/14/2021 11 Blood Volume • Most animals will go into shock if 25-30% of their blood (approx 2% of body wt) is removed over a short period of time • up to 2% of the body weight blood can be removed at one time at slow rate if replaced promptly with warm sterile fluids at a slow and steady rate
4/14/2021 12 • Removal of 30-40% of the blood will lead to death in at least 50 % of animals • Most animals would die following removal of more than 40% of total blood volume • 10 % of circulating blood can be taken every 3-4 weeks • 1% of circulating blood can be taken every 24 hours
4/14/2021 13 Animal Site Volume for diagnostic Most Large Mammals Jugular or a Caudal vein but brachial veins and mammary veins are also used C – 100 ml S/G – 20 ml H -100 ml Pig Anterior vena cava, jugular vein, ear vein 10 ml Chicken Wing vein (brachial vein) 1 ml Dog /Cat Cephalic, saphenous, femoral, jugular, or recurrent metatarsal vein, heart* Dog – 2 ml Cat – 1 ml Mouse Heart, tail vein or artery, orbital sinus, lateral saphenous vein, puncture of foot or toe or tail clip. 0.1 ml Rat Heart, saphenous vein, tail vein or artery orbital plexus, lateral saphenous vein 0.25 ml Guinea pig Heart, saphenous vein, ear vein 0.5 ml Rabbit Heart, marginal ear vein (small amounts), auricular artery (large amounts) 1 ml
4/14/2021 14 2. Serum • Serological analysis • Blood should be left in slanting position at RT • Preservatives, such as boric acid or merthiolate should be avoided in sera to be used in virus neutralization tests • Generally collected early in the course of disease and during convalescence (paired sera) • In outbreak of an exotic disease, a single positive reaction should be considered highly significant
4/14/2021 15 3. Faeces/Dung • Freshly voided faeces • Avoid contaminating sample with urine • Alternative method is to take swabs from the rectum (or cloaca) • For parasitology, fill the container and sent to laboratory within 24 hours • If transport times are likely to be longer than 24 hours, the sample should be sent on ice or refrigerated to prevent the hatching of parasite eggs
4/14/2021 16 • Screw top containers or sterile plastic bags should be used for shipment • Avoid tubes with rubber stoppers • Swabs may also be transported either dry or in transport medium • Faeces are best stored and transported at 4°C
4/14/2021 17 4. Milk • Usually for detection of sub-clinical mastitis and Brucellosis • should be taken after cleansing the tip of the teat • Discard initial stream of milk • Milk samples are preserved in ice and sent to the laboratory
4/14/2021 18 5. Skin, Epithelium and Hairs/Wool • Plucked hair or wool for mites, lice and fungal infections • In diseases producing vesicular rashes or where lesions are exclusively in the skin • Scrapings of the lesion may be taken • vesicular fluid should be sampled from unruptured vesicles
4/14/2021 19 5. Eye and Nasal discharge • Samples may be taken by soaking sterile cotton swabs that are wetted with transport medium and placed in a sterile glass vial and sent to the laboratory at 4˚ C • Metal-handled swabs are useful for Scraping to ensure sufficient cells are removed for microscopic examination
4/14/2021 20 6. Genital tract and Semen • vaginal or prepuce washing, or by the use of suitable swabs • Sometimes the cervix or urethra is also sampled by swabbing • Samples of semen are best collected using artificial vagina or by the extrusion of penis and artificial stimulation • samples collected in a sterile tube can be sent in ice to the nearest laboratory
4/14/2021 21 7. Urine • Urine samples can be obtained as free catch (mid stream voided) • Cystocentasis and catheterization. • Cystocentesis simplify the interpretation of results by eliminating the possibility of contamination from urethra and genital system • Collected in a clean, polypropylene container without preservatives. • Urine specimens may be transported at 18–25°C
4/14/2021 22 • Urine specimens that will not be processed within 24 hours of collection must be stored at 2–8°C. • Specimens stored at 2–8°C must be processed within seven days of collection • Specimens that cannot be processed within seven days may be stored at –20°C or colder
4/14/2021 23 8. Pus /Abscess • Remove surface exudates by wiping with sterile saline or 70% alcohol and sample the leading edge of an open abscess • A closed abscess should be aspirated with a needle and syringe after sterilizing skin with iodine or isopropyl alcohol wipes • An aspirate is always superior to a swab specimen • Swab samples are suboptimal for bacterial culture (aerobic or anaerobic) because of low specimen collection volume and exposure to oxygen (anaerobes).
4/14/2021 24 • If abscess is open, ensure all pus and cellular debris is removed, then swab deep into the lesion and firmly sample the lesions advancing edge. • If aspirate is obtained, do not submit sample in needle and syringe • If requests are being made for more than one test on a swab taken from a specific site, i.e. bacterial culture aerobes, bacterial culture anaerobes and fungus culture, please ensure that a separate swab sample is submitted for each test requested.
4/14/2021 25 9. Cerebral Spinal Fluid Collection • Lumbar puncture must be performed under conditions of strict asepsis. Handle as Emergency specimen: hand carry to laboratory. • At least one tube (second or third collection) must be sent to bacteriology first, before other studies such as cell count and chemistries are done. • Transport as soon as possible (≤15 minutes) • Samples being submitted for viral cultures only should be held/stored at 4˚C.
Sample Collection: Dead Animal 4/14/2021 26 • Examine animals that : • Are sacrificed or recently dead • had been acutely and typically affected • had not been treated • Target the affected organ or system • If signs are of GI disorder, examine and sample it first. Otherwise, examine and sample it (almost) last • In small animals, entire organs instead of samples may be collected
4/14/2021 27 • When to examine and sample brain • if signs are of CNS disorder • if signs are of a condition in which a CNS lesion is typical • if lesions elsewhere do not account for all signs • samples including abnormal areas and surrounding normal areas • samples no thicker than 1 cm, but long and wide enough to represent different areas of a tissue and possible abnormalities • Mechanical damaging of samples, for instance by compressing them with forceps, must be avoided
4/14/2021 28 1.Tissue impression slides • Pressing the clean non-greasy slide against the cut part of the organ/tissue after blotting with filter paper can make the tissue impression slides • slides are dried and fixed with methyl alcohol • slides should be dispatched in the slide box packed properly
4/14/2021 29 2. Organ or tissue • Tissues may be collected for • Culture • Histopathology • For use as Antigen in Serological Tests • Cut the affected organ (<1.5 cm) such that the cut part should have the affected part along with some normal organ
4/14/2021 30 • Each piece of tissue should be placed in a separate sterile screw-capped jar or plastic bag • for histopathological examination, the vial should have 10% formal saline • container should be labeled with the date, tissue and animal identification • Care must be taken not to contaminate one tissue with another
4/14/2021 31 3. Intestinal content • Collect content of the entire alimentary tract for food analysis • Examination of the stomach content alone may not be sufficient • Contents of the digestive tract can be preserved in 5% formalin or 30-40% alcohol • Whole alimentary tract may be preserved in formalin, after injection of formalin into the stomach, for later analysis
4/14/2021 32 • Samples may be taken • from water and feed troughs, • Soil and pastures • litter • ventilation ducts and drains • hatcheries and slaughter houses • To monitor • Hygiene • As part of disease investigation
Labeling of Sample 4/14/2021 33 • Processing and conservation of samples depend on the type of examination to be undertaken • As critical as proper specimen selection and preservation • Proper labeling and maintaining label readability • preventing label separation from specimens • The label should be as close to the specimen as possible • label should be attached to a carcass • attached to a tube of blood • placed within the vial of preservative with a parasite
4/14/2021 34 • Double labeling, whenever practical, is worth the effort • Use soft lead pencil or waterproof ink on tags • Photographing external and internal lesions provides a record of the color, location, and appearance of lesions • Include in the photograph for scale a coin or another readily recognized indicator of actual size
Specimen Preservation 4/14/2021 35 • Formalin preservation can be used for • specimens for histological examination • for fluid-preserved specimens • should not be used to preserve specimens • for preparation of skeletal material, • for microbial examination or • for preparation of study skins and mounted specimens • Formalin discolors fur and, after a longish immersion, softens the bones • Preservation in alcohol is useful for long term storage of tissues already preserved in formalin
Specimen Preservation 4/14/2021 36 • Whole animal can also be preserved in a container of alcohol (70- 90%) • Removal of the intestines prior to storage of the animal in alcohol is recommended • Chill or freeze all specimens, depending on how long it will take to ship to a diagnostic laboratory • Freezing reduces the diagnostic usefulness of carcasses and tissues, but if specimens must be held for 2 or more days, freezing the specimens as soon as possible after collecting them minimizes their decomposition • Formalin-fixed tissues should not be frozen
Packaging of samples 4/14/2021 37 • laboratory receiving the samples must be contacted in advance • to ensure that it has the facilities to carry the required tests • to know if there are any special packaging or shipment requirements • The packaging must consist of three components: 1. leak-proof primary receptacle 2. leak-proof secondary packaging 3. Rigid outer packaging of adequate strength • Strong glass container with a metal screw cap with rubber washer should be used and tape should be wrapped around the cap to prevent the risk of leakage of sample or media
4/14/2021 38 • Information for identification of material should be attached to the bottle written on waterproof adhesive tape • The outside of bottle must be disinfected before proceeding any further. • The bottle should be wrapped in absorbent cotton wool or in corrugated paper • This wrapped primary receptacle bottle should be placed in a well labeled metal container in which it fits and should be leakage proof, preferably a screw cap with rubber washer • This metal container is placed in a solid outer covering to prevent its distortion. A solid cardboard tube or wooden box with metal lid is satisfactory. • Clearly labeled and securely wrapped with adhesive tape or string.
Packaging of samples 4/14/2021 39
Transport of samples 4/14/2021 40 • Samples must be carefully packed, to avoid any possibility of leakage or cross contamination • should be delivered within 48 hours and must be kept cool during transit • Some samples should not be frozen • Screw-capped bottles should be used and should be additionally sealed with adhesive tape or paraffin wax
4/14/2021 41 • Samples in individually identified containers should be placed in larger strong, outer containers and packed with enough absorbent material to protect from damage • Official shipping regulations must be consulted • It is advisable to contact the laboratory in advance in the case of unusual requests • It is essential to do so, where material is sent to a laboratory in another country
Information to be sent 4/14/2021 42 • Information and case history should always accompany • The information should include the following points: 1. Name and address of owner with telephone number 2. Disease suspected and tests required (transport medium used) 3. description of the samples submitted for examination, and post-mortem findings and date of collection 4. Different species on the farm and number, age and sex of each affected animal
4/14/2021 43 5. Length of time on the farm; if recent arrival, where from 6. Date of first cases and of subsequent cases or losses 7. Description of the spread of infection in the herd or flock 8. Number of animals dead, the number showing clinical signs, and their age, sex and breed 9. clinical signs and their duration including the condition of mouth, eyes and feet, and milk or egg production data
4/14/2021 44 10. Type and standard of husbandry, including the type of feed available, possible contact with poison or poisonous plants 11. Any medication and/or vaccination already given to the animals, and when given 12. Separate vials of preservative and transport media used 13. Name and address of sender, with telephone and fax number, and date of submission.
Conditions for Rejection of Samples 4/14/2021 45 • Samples which are not of adequate quality are labile to be rejected • there can be number of things which the sample collector or the respective veterinarian must ensure in order to avoid the rejection of samples • Error in name, number, identification and address • Missing of samples, summary sheet of the batch submitted, specimen label or seal • Insufficient quantity or absence of specimens • Tempered or more than one labels on specimen • Repeated specimen number or duplicate specimens in the same security box
Precautions for Quality Sample 4/14/2021 46 • Trained personnel • Proper documentation of sample • Collect specimen in duplicate • Appropriate transport media and preservative • Securely seal and label • Maintain the proper temperature during transit • Provide all desired information on separate letter • Rush the samples to the laboratory at the earliest • Conducted PM at the earliest and attached report

More Related Content

Collection, Preservation and Dispatch of Clinical Samples

  • 1. Collection, Preservation and Dispatch of Clinical Samples 4/14/2021 1 Dr. Vinod Kumar Singh Department of Veterinary Microbiology DUVASU, Mathura
  • 2. Need of Sample collection 4/14/2021 2 • Establishing a disease diagnosis • For Health Surveillance • For the Monitoring of Response to Treatment • For the Monitoring of Response to Vaccines • Aid in choosing the right choice of drug: ABST
  • 3. Ensure before Sampling 4/14/2021 3 • What will I have to do? • What are the associated risks? • Personal safety Biosecurity • What do I need to do the job safely and securely?
  • 4. 4/14/2021 4 • Boots, gloves, overalls, eye-wear, face mask, first aid kit • Forms (Specimen Advice, key list) • Writing equipment, camera, phone • Disinfectant for instruments, containers, collection site and operators hands
  • 5. 4/14/2021 5 • Equipment and drugs for animal restraint • Equipment for animal identification • Equipment for clinical examination • Instruments for necropsy, biopsy, blood collection • Specimen packaging containers • Water
  • 6. Keep a small kit ready 4/14/2021 6
  • 7. Sample size 4/14/2021 7 S. No. Sample Size 1 Feces 10 gm 3. Organs/tissue 1-1.5 cm3 4. Blood 10 % of blood volume with fluid replacement
  • 8. Sample Collection 4/14/2021 8 • Samples may be taken from • animals-dead or alive : intact carcass, tissues removed from carcasses, parasites, ingested food, feces, blood • their environment • consider personal safety and avoid injury or distress to the animal • Prior to collection note • the distribution • Color and morphological description • size and odor of the lesions
  • 9. 4/14/2021 9 • Every carcass be treated as a potential health hazard • Knowledge of pathogenesis of infectious disease • Separate samples for microscopic examination, microbiology, toxicology, and other analyses • Try to obtain a minimum of five specimens per species • Time of collection is also important in some cases
  • 10. Sample Collection: live animal 4/14/2021 10 1.Blood • Ideally the skin at the site of vein puncture should be shaved (plucked) first and swabbed with 70 % ethyl alcohol • Taken by syringe and needle or by needle and vacuum tube • When taken from small veins it is better to use a syringe • For virology, antibiotics may be added • For samples with anti-coagulant and/ or antibiotics, thorough mixing is necessary
  • 11. 4/14/2021 11 Blood Volume • Most animals will go into shock if 25-30% of their blood (approx 2% of body wt) is removed over a short period of time • up to 2% of the body weight blood can be removed at one time at slow rate if replaced promptly with warm sterile fluids at a slow and steady rate
  • 12. 4/14/2021 12 • Removal of 30-40% of the blood will lead to death in at least 50 % of animals • Most animals would die following removal of more than 40% of total blood volume • 10 % of circulating blood can be taken every 3-4 weeks • 1% of circulating blood can be taken every 24 hours
  • 13. 4/14/2021 13 Animal Site Volume for diagnostic Most Large Mammals Jugular or a Caudal vein but brachial veins and mammary veins are also used C – 100 ml S/G – 20 ml H -100 ml Pig Anterior vena cava, jugular vein, ear vein 10 ml Chicken Wing vein (brachial vein) 1 ml Dog /Cat Cephalic, saphenous, femoral, jugular, or recurrent metatarsal vein, heart* Dog – 2 ml Cat – 1 ml Mouse Heart, tail vein or artery, orbital sinus, lateral saphenous vein, puncture of foot or toe or tail clip. 0.1 ml Rat Heart, saphenous vein, tail vein or artery orbital plexus, lateral saphenous vein 0.25 ml Guinea pig Heart, saphenous vein, ear vein 0.5 ml Rabbit Heart, marginal ear vein (small amounts), auricular artery (large amounts) 1 ml
  • 14. 4/14/2021 14 2. Serum • Serological analysis • Blood should be left in slanting position at RT • Preservatives, such as boric acid or merthiolate should be avoided in sera to be used in virus neutralization tests • Generally collected early in the course of disease and during convalescence (paired sera) • In outbreak of an exotic disease, a single positive reaction should be considered highly significant
  • 15. 4/14/2021 15 3. Faeces/Dung • Freshly voided faeces • Avoid contaminating sample with urine • Alternative method is to take swabs from the rectum (or cloaca) • For parasitology, fill the container and sent to laboratory within 24 hours • If transport times are likely to be longer than 24 hours, the sample should be sent on ice or refrigerated to prevent the hatching of parasite eggs
  • 16. 4/14/2021 16 • Screw top containers or sterile plastic bags should be used for shipment • Avoid tubes with rubber stoppers • Swabs may also be transported either dry or in transport medium • Faeces are best stored and transported at 4°C
  • 17. 4/14/2021 17 4. Milk • Usually for detection of sub-clinical mastitis and Brucellosis • should be taken after cleansing the tip of the teat • Discard initial stream of milk • Milk samples are preserved in ice and sent to the laboratory
  • 18. 4/14/2021 18 5. Skin, Epithelium and Hairs/Wool • Plucked hair or wool for mites, lice and fungal infections • In diseases producing vesicular rashes or where lesions are exclusively in the skin • Scrapings of the lesion may be taken • vesicular fluid should be sampled from unruptured vesicles
  • 19. 4/14/2021 19 5. Eye and Nasal discharge • Samples may be taken by soaking sterile cotton swabs that are wetted with transport medium and placed in a sterile glass vial and sent to the laboratory at 4˚ C • Metal-handled swabs are useful for Scraping to ensure sufficient cells are removed for microscopic examination
  • 20. 4/14/2021 20 6. Genital tract and Semen • vaginal or prepuce washing, or by the use of suitable swabs • Sometimes the cervix or urethra is also sampled by swabbing • Samples of semen are best collected using artificial vagina or by the extrusion of penis and artificial stimulation • samples collected in a sterile tube can be sent in ice to the nearest laboratory
  • 21. 4/14/2021 21 7. Urine • Urine samples can be obtained as free catch (mid stream voided) • Cystocentasis and catheterization. • Cystocentesis simplify the interpretation of results by eliminating the possibility of contamination from urethra and genital system • Collected in a clean, polypropylene container without preservatives. • Urine specimens may be transported at 18–25°C
  • 22. 4/14/2021 22 • Urine specimens that will not be processed within 24 hours of collection must be stored at 2–8°C. • Specimens stored at 2–8°C must be processed within seven days of collection • Specimens that cannot be processed within seven days may be stored at –20°C or colder
  • 23. 4/14/2021 23 8. Pus /Abscess • Remove surface exudates by wiping with sterile saline or 70% alcohol and sample the leading edge of an open abscess • A closed abscess should be aspirated with a needle and syringe after sterilizing skin with iodine or isopropyl alcohol wipes • An aspirate is always superior to a swab specimen • Swab samples are suboptimal for bacterial culture (aerobic or anaerobic) because of low specimen collection volume and exposure to oxygen (anaerobes).
  • 24. 4/14/2021 24 • If abscess is open, ensure all pus and cellular debris is removed, then swab deep into the lesion and firmly sample the lesions advancing edge. • If aspirate is obtained, do not submit sample in needle and syringe • If requests are being made for more than one test on a swab taken from a specific site, i.e. bacterial culture aerobes, bacterial culture anaerobes and fungus culture, please ensure that a separate swab sample is submitted for each test requested.
  • 25. 4/14/2021 25 9. Cerebral Spinal Fluid Collection • Lumbar puncture must be performed under conditions of strict asepsis. Handle as Emergency specimen: hand carry to laboratory. • At least one tube (second or third collection) must be sent to bacteriology first, before other studies such as cell count and chemistries are done. • Transport as soon as possible (≤15 minutes) • Samples being submitted for viral cultures only should be held/stored at 4˚C.
  • 26. Sample Collection: Dead Animal 4/14/2021 26 • Examine animals that : • Are sacrificed or recently dead • had been acutely and typically affected • had not been treated • Target the affected organ or system • If signs are of GI disorder, examine and sample it first. Otherwise, examine and sample it (almost) last • In small animals, entire organs instead of samples may be collected
  • 27. 4/14/2021 27 • When to examine and sample brain • if signs are of CNS disorder • if signs are of a condition in which a CNS lesion is typical • if lesions elsewhere do not account for all signs • samples including abnormal areas and surrounding normal areas • samples no thicker than 1 cm, but long and wide enough to represent different areas of a tissue and possible abnormalities • Mechanical damaging of samples, for instance by compressing them with forceps, must be avoided
  • 28. 4/14/2021 28 1.Tissue impression slides • Pressing the clean non-greasy slide against the cut part of the organ/tissue after blotting with filter paper can make the tissue impression slides • slides are dried and fixed with methyl alcohol • slides should be dispatched in the slide box packed properly
  • 29. 4/14/2021 29 2. Organ or tissue • Tissues may be collected for • Culture • Histopathology • For use as Antigen in Serological Tests • Cut the affected organ (<1.5 cm) such that the cut part should have the affected part along with some normal organ
  • 30. 4/14/2021 30 • Each piece of tissue should be placed in a separate sterile screw-capped jar or plastic bag • for histopathological examination, the vial should have 10% formal saline • container should be labeled with the date, tissue and animal identification • Care must be taken not to contaminate one tissue with another
  • 31. 4/14/2021 31 3. Intestinal content • Collect content of the entire alimentary tract for food analysis • Examination of the stomach content alone may not be sufficient • Contents of the digestive tract can be preserved in 5% formalin or 30-40% alcohol • Whole alimentary tract may be preserved in formalin, after injection of formalin into the stomach, for later analysis
  • 32. 4/14/2021 32 • Samples may be taken • from water and feed troughs, • Soil and pastures • litter • ventilation ducts and drains • hatcheries and slaughter houses • To monitor • Hygiene • As part of disease investigation
  • 33. Labeling of Sample 4/14/2021 33 • Processing and conservation of samples depend on the type of examination to be undertaken • As critical as proper specimen selection and preservation • Proper labeling and maintaining label readability • preventing label separation from specimens • The label should be as close to the specimen as possible • label should be attached to a carcass • attached to a tube of blood • placed within the vial of preservative with a parasite
  • 34. 4/14/2021 34 • Double labeling, whenever practical, is worth the effort • Use soft lead pencil or waterproof ink on tags • Photographing external and internal lesions provides a record of the color, location, and appearance of lesions • Include in the photograph for scale a coin or another readily recognized indicator of actual size
  • 35. Specimen Preservation 4/14/2021 35 • Formalin preservation can be used for • specimens for histological examination • for fluid-preserved specimens • should not be used to preserve specimens • for preparation of skeletal material, • for microbial examination or • for preparation of study skins and mounted specimens • Formalin discolors fur and, after a longish immersion, softens the bones • Preservation in alcohol is useful for long term storage of tissues already preserved in formalin
  • 36. Specimen Preservation 4/14/2021 36 • Whole animal can also be preserved in a container of alcohol (70- 90%) • Removal of the intestines prior to storage of the animal in alcohol is recommended • Chill or freeze all specimens, depending on how long it will take to ship to a diagnostic laboratory • Freezing reduces the diagnostic usefulness of carcasses and tissues, but if specimens must be held for 2 or more days, freezing the specimens as soon as possible after collecting them minimizes their decomposition • Formalin-fixed tissues should not be frozen
  • 37. Packaging of samples 4/14/2021 37 • laboratory receiving the samples must be contacted in advance • to ensure that it has the facilities to carry the required tests • to know if there are any special packaging or shipment requirements • The packaging must consist of three components: 1. leak-proof primary receptacle 2. leak-proof secondary packaging 3. Rigid outer packaging of adequate strength • Strong glass container with a metal screw cap with rubber washer should be used and tape should be wrapped around the cap to prevent the risk of leakage of sample or media
  • 38. 4/14/2021 38 • Information for identification of material should be attached to the bottle written on waterproof adhesive tape • The outside of bottle must be disinfected before proceeding any further. • The bottle should be wrapped in absorbent cotton wool or in corrugated paper • This wrapped primary receptacle bottle should be placed in a well labeled metal container in which it fits and should be leakage proof, preferably a screw cap with rubber washer • This metal container is placed in a solid outer covering to prevent its distortion. A solid cardboard tube or wooden box with metal lid is satisfactory. • Clearly labeled and securely wrapped with adhesive tape or string.
  • 40. Transport of samples 4/14/2021 40 • Samples must be carefully packed, to avoid any possibility of leakage or cross contamination • should be delivered within 48 hours and must be kept cool during transit • Some samples should not be frozen • Screw-capped bottles should be used and should be additionally sealed with adhesive tape or paraffin wax
  • 41. 4/14/2021 41 • Samples in individually identified containers should be placed in larger strong, outer containers and packed with enough absorbent material to protect from damage • Official shipping regulations must be consulted • It is advisable to contact the laboratory in advance in the case of unusual requests • It is essential to do so, where material is sent to a laboratory in another country
  • 42. Information to be sent 4/14/2021 42 • Information and case history should always accompany • The information should include the following points: 1. Name and address of owner with telephone number 2. Disease suspected and tests required (transport medium used) 3. description of the samples submitted for examination, and post-mortem findings and date of collection 4. Different species on the farm and number, age and sex of each affected animal
  • 43. 4/14/2021 43 5. Length of time on the farm; if recent arrival, where from 6. Date of first cases and of subsequent cases or losses 7. Description of the spread of infection in the herd or flock 8. Number of animals dead, the number showing clinical signs, and their age, sex and breed 9. clinical signs and their duration including the condition of mouth, eyes and feet, and milk or egg production data
  • 44. 4/14/2021 44 10. Type and standard of husbandry, including the type of feed available, possible contact with poison or poisonous plants 11. Any medication and/or vaccination already given to the animals, and when given 12. Separate vials of preservative and transport media used 13. Name and address of sender, with telephone and fax number, and date of submission.
  • 45. Conditions for Rejection of Samples 4/14/2021 45 • Samples which are not of adequate quality are labile to be rejected • there can be number of things which the sample collector or the respective veterinarian must ensure in order to avoid the rejection of samples • Error in name, number, identification and address • Missing of samples, summary sheet of the batch submitted, specimen label or seal • Insufficient quantity or absence of specimens • Tempered or more than one labels on specimen • Repeated specimen number or duplicate specimens in the same security box
  • 46. Precautions for Quality Sample 4/14/2021 46 • Trained personnel • Proper documentation of sample • Collect specimen in duplicate • Appropriate transport media and preservative • Securely seal and label • Maintain the proper temperature during transit • Provide all desired information on separate letter • Rush the samples to the laboratory at the earliest • Conducted PM at the earliest and attached report

Editor's Notes

  1. The basic supplies and equipment that should be included in a field kit for specimen collection will vary with the species being sampled and the types of analyses that will be conducted
  2. In addition to the choice of the samples, the size and the amount of the sample is also vital importance for an accurate laboratory diagnosis. There are some general statistical rules one should borne in mind before taking microbiological samples, particularly when sampling herds or flocks for a health surveillance scheme. It is possible to calculate how many animals must be sampled from a herd/ flock of a certain size, to achieve a 95 % probability infection assumed to be present in a certain percentage of the animals.
  3. For many infectious diseases, the agent can be identified from blood, by detection of antigens or culture and isolation of the agent, or demonstration of DNA usually 200 units of penicillin and 200 mg of streptomycin per ml
  4. A positive serological reaction does not necessary means that the animal is clinically infected: vaccination, post-infection immunity, persistence of maternal antibodies in young animals, and lack of specificity of the test, are common cause of "false" positive. Therefore, when possible it is always better to provide either paired samples from the same animal with 2-3 weeks between sampling or from different animals at different stage of the disease. However in an outbreak of an exotic disease, a single positive reaction should be considered highly significant. Generally serum samples early in the course of disease (acute, within 1 -4 day s) and during convalescence (convalescent, around 21 days) are collected. Such samples are called paired serum samples and are used to demonstrate the rising antibody titre.
  5. Improperly collected, packed and labeled or shipped specimen is not only illegal but also causes considerable inconvenience and wastage of time and money to both involved in collection and dispatch and to the laboratory personals.