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Dossier Vaccination: what causes poultry vaccination to fail

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This is the third presentation on vaccination, posted recently by Dr. Ossama Motawae, an Egyptian veterinarian. In this presentation, he explains what causes vaccination programs to fail. An interesting presentation for those who are not so familiar with the day-to-day practice of poultry vaccination.

Published in: Health & Medicine

Dossier Vaccination: what causes poultry vaccination to fail

  1. 1. Vaccination Failure
  2. 2. Contents 1. Types Of Vaccines 2. Method Of Vaccination 3. Causes Of Vaccination Failure 4. Seological Monitoring
  3. 3. TYPES OF VACCINES
  4. 4. A live-type poultry vaccine
  5. 5. Types of Vaccines A live-type poultry vaccine  It contains a virus or bacteria that must infect the chicken and multiply in its body to produce immunity, preferably with minimal reaction.  This multiplication of the virus in the chicken is necessary because only relatively small amounts of virus are administered to the bird.  By multiplying in the chicken, increased amounts of virus are recognized by the chicken's immune system, thus an enhanced immune response results
  6. 6. Types of Vaccines A live-type poultry vaccine Advantages of live-type vaccines are: 1. Ease of administration. 2. Low price. 3. Rapid onset of immunity. 4. Broader scope of protection because chickens are exposed to all stages of the replicating virus.
  7. 7. Types of Vaccines A live-type poultry vaccine Disadvantages of live-type vaccines are: : 1. Problems with uniform vaccine application. 2. Excessive vaccine reactions. 3. Unwanted spread of the vaccine virus to neighboring poultry houses. 4. Extreme handling requirements needed to maintain viability of the vaccine organism.
  8. 8. A killed-type poultry vaccine
  9. 9. Types of Vaccines A killed-type poultry vaccine  A killed-type poultry vaccine is prepared from bacteria or viruses that have been inactivated and processed, thus will not spread from bird-to-bird, and requires individual injection.  Killed vaccines are usually combined with an adjuvant such as aluminum hydroxide or an oil.  Adjuvants enhance the immune response by increasing the stability of the vaccine in the body, which then stimulates the immune system for a longer period of time.
  10. 10. Types of Vaccines A killed-type poultry vaccine Advantages of killed-type vaccines are: 1. Assurance of administration of a uniform dose (birds are individually injected) 2. Safety (the organism has been inactivated) 3. Development of uniform levels of immunity (each bird receives the same dose) 4. No chance for spread of vaccine organism to neighboring poultry farms 5. Increased product stability, and a choice of a wider variety of virus strains.
  11. 11. Types of Vaccines A killed-type poultry vaccine Disadvantages of killed-type vaccines are: 1. Increased costs (labor and product). 2. Slower onset of immunity. 3. Narrower spectrum of protection. 4. Presence of localized tissue damage at site of injection due to reaction with the adjuvant.
  12. 12. METHODS OF VACCINE APPLICATION
  13. 13. Methods of Vaccine- Application • Individual application 1. Eye drop 2. Beak dipping 3. Injection 4. Wing web • Mass application 1. Spray 2. Drinking water Road Map
  14. 14. Methods of Vaccine- Application • Individual application 1. Eye drop 2. Beak dipping 3. Injection 4. Wing web • Mass application 1. Spray 2. Drinking water Road Map
  15. 15. Methods of Vaccine- Application • Individual application 1. Eye drop 2. Beak dipping 3. Injection 4. Wing web • Mass application 1. Spray 2. Drinking water Road Map
  16. 16. Very efficient Highly labour intensive Use only specific diluent
  17. 17. Good Practice of Eye-Drop Vaccination  Prepare the vaccine suspension with the appropriate diluent.  Use the calibrated dropper (1,000 doses in 30 ml).  20 minutes for 1,000 birds.  Hold the bottle in upside down position and apply one drop per bird onto the eye or into the nasal duct.
  18. 18. Good Practice of Eye-Drop Vaccination  Avoid bottle contact with mucosa of eye or nostrils.  Compulsory route of vaccination for e.g. ILT, Mg.  Simultaneous vaccination with inactivated vaccines is possible.
  19. 19. Methods of Vaccine- Application • Individual application 1. Eye drop 2. Beak dipping 3. Injection 4. Wing web • Mass application 1. Spray 2. Drinking water Road Map
  20. 20. Methods of Vaccine- Application • Individual application 1. Eye drop 2. Beak dipping 3. Injection 4. Wing web • Mass application 1. Spray 2. Drinking water Road Map
  21. 21. Very efficient Highly labour intensive Use only specific diluent
  22. 22. Good Practice of Beak-Dipping Vaccination  Prepare the vaccine suspension with distilled water.  Use about 150 - 200 ml per 1,000 chicks.  Dip the beak of each bird up to the nostrils.
  23. 23. Good Practice of Beak-Dipping Vaccination Advantages: 1. Fast and easy vaccination during the first days of life. 2. All birds can be immunized. 3. Avoids problems with irregular water consumption. 4. Avoids respiratory reactions as seen after spray vaccination. 5. Simultaneous vaccination with inactivated vaccines is possible.
  24. 24. Methods of Vaccine- Application • Individual application 1. Eye drop 2. Beak dipping 3. Injection 4. Wing web • Mass application 1. Spray 2. Drinking water Road Map
  25. 25. Methods of Vaccine- Application • Individual application 1. Eye drop 2. Beak dipping 3. Injection 4. Wing web • Mass application 1. Spray 2. Drinking water Road Map
  26. 26. Very efficient Highly labour intensive Use only sterile equipment
  27. 27. Correct Incorrect
  28. 28. Intramuscular & Subcutaneous Vaccination Good Practice of Intramuscular & Subcutaneous Vaccination 1. Use sterile equipment only. 2. Change needle every 800 birds. 3. Dilute live vaccines in their appropriate diluent. 4. Oil vaccines should have room-temperature before application. 5. Needle diameter: 1. 1,2 mm = 18 G; Length of 0,7 cm for s.c. 2. 1,0 - 1,3 cm for i.m. 6. Subcutaneous route: Inject into the lower part of the neck. 7. Intramuscular route: Inject tangential into the breast muscle.
  29. 29. Methods of Vaccine- Application • Individual application 1. Eye drop 2. Beak dipping 3. Injection 4. Wing web • Mass application 1. Spray 2. Drinking water Road Map
  30. 30. Methods of Vaccine- Application • Individual application 1. Eye drop 2. Beak dipping 3. Injection 4. Wing web • Mass application 1. Spray 2. Drinking water Road Map
  31. 31. Factors affecting water and spray vaccination Bird 1. Immunocompetence 2. Water consumption 3. Maternal antibodies 4. Drinker space 5. Ambient temperature Vaccine 1. Virus stability in water 2. Lateral spread of vaccine virus 3. Immunogenicity of vaccine 4. Vaccination timing 5. Virus concentration in water
  32. 32. Factors affecting water and spray vaccination Water vaccination 1. Volume 2. Time of water withdrawal 3. Water quality 4. Type of drinker 5. Method of delivery Spray vaccination 1. Volume 2. Particle size 3. Relative humidity 4. House design 5. Distribution of spray 6. Uniformity of droplets
  33. 33. Spray Vaccination Spray vaccination Rapid Good immune response Post vaccinal reactions Use distilled water only
  34. 34. Good Practice of Spray Vaccination Two methods of spray vaccination: (not suitable for diseased and Mg positive birds) 1. Coarse spray: • Droplet-size: 70 - 150 μ. • Recommended during the first 3 weeks of age and for first vaccination. 2. Fine spray: • Droplet-size: 15 - 50 μ. • Reserved for ND booster-vaccination.
  35. 35. Good Practice of Spray Vaccination 1. Select correct spray equipment. 2. Spray equipment has to be clean, free from disinfectants and used for this purpose only. 3. Equipment has to be well maintained and adjusted. 4. Use distilled water for preparing the vaccine solution. 5. Darken the animal house and turn off ventilation during vaccination and up to 30 minutes after vaccination. 6. Gather the birds calmly in a restricted area, if necessary. 7. Walk slowly through the animal house during vaccination (~ 20 minutes). 8. Spray in direction to the heads of the chicken. 9. Distribute the vaccine evenly. 10.Hatchery: Spray 3 seconds on each box of 100 chicks.
  36. 36. Good Practice of Spray Vaccination Quantity of water needed is related to: 1. Number and age of chicken. 2. Equipment to be used. 3. Ambient conditions: temperature & humidity (rate of evaporation). 4. All chicks have to be hit by the spray (shake the head for a moment). 5. All chicks heads have to get slightly moist. 6. Vaccination in two applications might be necessary. 7. Perform a sham vaccination in order to assess time and volume of water needed!
  37. 37. Spray Vaccination: The following table gives some examples: Vaccination with coarse mist Vaccination with fine mist Mean size of the drops > 50 μm < 50 μm Flow/ pressure 500–600 ml/min. 2–3 bar 50 ml/min. Vol./1000 birds 500–1000 ml 100–200 ml Duration of spraying for 1000 birds 1–2 min. 5 min.
  38. 38. Methods of Vaccine- Application • Individual application 1. Eye drop 2. Beak dipping 3. Injection 4. Wing web • Mass application 1. Spray 2. Drinking water Road Map
  39. 39. Methods of Vaccine- Application • Individual application 1. Eye drop 2. Beak dipping 3. Injection 4. Wing web • Mass application 1. Spray 2. Drinking water Road Map
  40. 40. Drinking Water Vaccination Drinking water vaccination Rapid Easy Safe Economic No disinfectants Control water system and drinker Control water quality
  41. 41. Drinking-Water Vaccination Good Practice of Drinking-Water Vaccination  Discontinue the drinking-water disinfection at least 3 days before vaccination.  Clean tanks, tubes and drinkers / nipples one day before vaccination with clean water; don’t use soap or disinfectant.  Dosing pumps are not preferred, but if they are used, use a separate pump which is used for vaccinations only.  For preparing the water-vaccine mixture, use only clean plastic buckets and tools, which must not be used for other purposes.
  42. 42. Drinking-Water Vaccination Determine the volume of water needed for a 2 h uptake: The volume of water varies and is mainly influenced by: 1. Number of chicken 2. Breed 3. Age 4. Temperature 5. Feed
  43. 43. Drinking-Water Vaccination Carry out a test vaccination one day before without vaccine but with skimmed milk powder in order to: 1. Ascertain the adequate time of water deprivation (1-2h). 2. Assess the water consumption during 2h. 3. Skimmed milk powder binds residual disinfectants in the tube system (“dead volumes”) and minerals.
  44. 44. Drinking-Water Vaccination Preparing the drinker system for vaccination: Before and during water deprivation (preferably in the morning)- 1. Ensure a sufficient amount of drinker or nipples. 2. Cut off the water supply. 3. Empty and drain off completely the whole drinker system. 4. Be aware of “dead volumes”.
  45. 45. Drinking-Water Vaccination Preparing the water-vaccine mixture: 1. Use correct number of vaccine-doses. Never under dose. 2. Prepare the water-vaccine mixture on a clean desk in a clean room, using a clean plastic bucket and tools. 3. Use only clean water of very good quality, e.g. mineral water, for dissolving the vaccine (small volume). 4. Add 0,2-0,25 % (2-2,5g/l) skimmed milk powder to the required volume of clean water of good quality (pH ~6, no bacteria, no chlorine, no metallic ions, no disinfectants) and mix well. 5. Mix well vaccine solution with the milky water by means of a plastic stirrer.
  46. 46. Drinking-Water Vaccination Perform drinking-water vaccination after water deprivation: 1. Fill and drain the whole drinker system with the milky water-vaccine mixture. 2. Make sure that milky water-vaccine mixture or dye arrives at each drinker, nipple and the end of tubes. 3. Make sure that all birds drink the water-vaccine solution by going slowly through the chicken house. 4. After complete consumption of the water-vaccine mixture in about 2h, refill the drinker system with clean water of good quality at its maximum and add skimmed milk powder.
  47. 47. Drinking-Water Vaccination Bell drinker: 1 / 80-100 birds Nipple drinker: 1 / 10-15 birds Cup drinker: 1 / 25-30 birds Troughs 6’: 1 / 150 birds Troughs 8’: 1 / 200 birds
  48. 48. Quality of drinking water according to EU norms: Parameter: Norms for Human Acceptable for poultry pH 6,5 – 8,5 (max. 9,5) Hardness 15°-30°(= 150 – 300 ppm Ca) Organic matter < 5 mg / liter Nitrate (NO 3) < 50 mg / liter Nitrite (NO 2) < 0,1 mg / liter Ammonium (NH 4) < 0,5 mg / liter Chlorine (Cl) < 200 mg / liter Iron (Fe) < 0,2 mg / liter Total germs < 10 colonies / 1 ml < 10 colonies / 100 ml Total coliform bact. 0 < 5 / 100 ml Total fecal coliform bact. 0 < 5 / 100 ml Fecal Streptococci 0 < 5 / 100 ml Clostridium spp 0 < 10 / 100 ml Staphylococci 0 0 Salmonella 0 0
  49. 49. Problem Effect Corrective Measurement Excessive time for vaccine solution to reach all birds Vaccine titer may drop below immunizing level Drain residual water and fill water system with vaccine under pressure (with dye) Excessive residual water in lines Delayed delivery of vaccine to birds at the end of waterlines Fill water system with vaccine (using dye) while simultaneously draining residual water Vaccine solution consumed in less than 1,5-2 hours Vaccine consumed by dominant birds only, too many unvaccinated remain Increase volume of vaccine stock solution Uneven application of vaccine Decrease water withdrawal
  50. 50. Problem Effect Corrective Measurement Correct volume of vaccine solution consumed in more than 2 hours Vaccine titer may drop below immunizing level Split vaccination into two successive vaccinations (50% + 50%) Airlocks Delayed delivery of vaccine to areas / tiers in the house Fill waterlines with vaccine (with dye) while draining residual water Uneven vaccination of flock Fill waterlines with vaccine before light comes in the morning Birds at back of battery, last cages do not receive vaccine Vaccine volume not enough to fill water system Increase volume of vaccine solution Uneven vaccination of cage row Drain residual water. Turn off lights while filling waterlines with vaccine
  51. 51. Vaccination Failure
  52. 52. Basics of Vaccination in Poultry Elements of a Vaccination Program Age of the first vaccination Type of vaccines Good Vaccination Program Design Interval between Subsequent vaccinations Route of vaccination Number of vaccinations 1. Stimulation & maintenance of protective immunity 2. Development of immunologic memory
  53. 53. Basics of Vaccination in Poultry Requirements for Good Immune Response Good nutrition Correct Good Immune Response No immune suppression Healthy birds vaccine storage Good administration technique Correct vaccination programme Correct vaccine No stress
  54. 54. What Is Vaccination Failure? A vaccination failure occurs when, following vaccine administration: The chickens do not develop adequate antibody titer levels. and/or The chickens are susceptible to a field disease outbreak.
  55. 55. What Is Vaccination Failure? When a vaccination fails, the natural inclination is to blame the vaccine, although there are other factors that must be evaluated to determine the cause of the failure.
  56. 56. Vaccination Failure - Bird
  57. 57. Causes Of Vaccination Failure / Bird • Maternal antibodies • Stress • Chickens may already be incubating the disease • Chickens may be immunosuppressed • Strong field challenge • Weaning of vaccine immunity Road Map
  58. 58. Causes Of Vaccination Failure / Bird • Maternal antibodies • Stress • Chickens may already be incubating the disease • Chickens may be immunosuppressed • Strong field challenge • Weaning of vaccine immunity Road Map
  59. 59. Maternal Antibodies A high level of maternal antibodies in the young chicken may interfere with the multiplication of live vaccines, reducing the amount of immunity produced.
  60. 60. Maternal Antibodies For example, If a chick comes from a breeder hen with high levels of antibody against Gumboro (Infectious Bursal Disease), the chick will typically have high levels of antibodies (maternal) for several weeks. If vaccination is attempted in the presence of these antibodies, some of the vaccine virus will be inactivated.
  61. 61. Causes Of Vaccination Failure / Bird • Maternal antibodies • Stress • Chickens may already be incubating the disease • Chickens may be immunosuppressed • Strong field challenge • Weaning of vaccine immunity Road Map
  62. 62. Causes Of Vaccination Failure / Bird • Maternal antibodies • Stress • Chickens may already be incubating the disease • Chickens may be immunosuppressed • Strong field challenge • Weaning of vaccine immunity Road Map
  63. 63. Stress Stress may reduce the chicken's ability to mount an immune response. Stress may include: 1. Environmental extremes (temperature, relative humidity) 2. Inadequate nutrition 3. Parasitism 4. Other diseases. Chickens should not be vaccinated during periods of stress, so it is better to delay vaccination until birds are healthy.
  64. 64. Causes Of Vaccination Failure / Bird • Maternal antibodies • Stress • Chickens may already be incubating the disease • Chickens may be immunosuppressed • Strong field challenge • Weaning of vaccine immunity Road Map
  65. 65. Causes Of Vaccination Failure / Bird • Maternal antibodies • Stress • Chickens may already be incubating the disease • Chickens may be immunosuppressed • Strong field challenge • Weaning of vaccine immunity Road Map
  66. 66. Chickens May Already Be Incubating The Disease  Chickens may already be incubating the disease at the time of vaccine administration.  Despite proper administration, birds become diseased because time is needed for antibody production to begin and reach protective levels.
  67. 67. Chickens May Already Be Incubating The Disease  Remember, after first exposure to a live virus-type vaccine, immunoglobulins G, M, and A are first detected approximately 4 to 5 days following exposure.  Additional days are required for titers to reach protective levels.
  68. 68. Causes Of Vaccination Failure / Bird • Maternal antibodies • Stress • Chickens may already be incubating the disease • Chickens may be immunosuppressed • Strong field challenge • Weaning of vaccine immunity Road Map
  69. 69. Causes Of Vaccination Failure / Bird • Maternal antibodies • Stress • Chickens may already be incubating the disease • Chickens may be immunosuppressed • Strong field challenge • Weaning of vaccine immunity Road Map
  70. 70. Chickens May Be Immunosuppressed  Chickens may be immunosuppressed due to infection with IBD virus or Mareks' disease virus, or from consumption of feed with high levels of mycotoxins.  The term immunosuppression refers to circumstances where the non-cellular (antibody) and cellular components of the immune system are not functioning properly.  This may result in the development of only limited protection from the vaccination and an excessive vaccine reaction with morbidity and mortality
  71. 71. Causes Of Vaccination Failure / Bird • Maternal antibodies • Stress • Chickens may already be incubating the disease • Chickens may be immunosuppressed • Strong field challenge • Weaning of vaccine immunity Road Map
  72. 72. Causes Of Vaccination Failure / Bird • Maternal antibodies • Stress • Chickens may already be incubating the disease • Chickens may be immunosuppressed • Strong field challenge • Weaning of vaccine immunity Road Map
  73. 73. Strong Field Challenge No vaccine can tolerate unlimited field challenge
  74. 74. Causes Of Vaccination Failure / Bird • Maternal antibodies • Stress • Chickens may already be incubating the disease • Chickens may be immunosuppressed • Strong field challenge • Weaning of vaccine immunity Road Map
  75. 75. Causes Of Vaccination Failure / Bird • Maternal antibodies • Stress • Chickens may already be incubating the disease • Chickens may be immunosuppressed • Strong field challenge • Weaning of vaccine immunity Road Map
  76. 76. Weaning Of Vaccine Immunity Antibodies are protein, subjected to metabolic breakdown.
  77. 77. Vaccination Failure - Vaccine
  78. 78. Causes Of Vaccination Failure / Vaccine • Live vaccines may be inactivated • The vaccine may not contain the proper strains • Poor distribution of live vaccine • Vaccine may be of poor quality Road Map
  79. 79. Causes Of Vaccination Failure / Vaccine • Live vaccines may be inactivated • The vaccine may not contain the proper strains • Poor distribution of live vaccine • Vaccine may be of poor quality Road Map
  80. 80. Live Vaccines May Be Inactivated  Live vaccines may be inactivated due to improper handling or administration.  Before administering live vaccines, check and record lot numbers and expiration dates on the vials.  Store and handle vaccines as recommended by the manufacturer.  Once a vaccine is reconstituted, the "time clock is ticking." Infectious bronchitis vaccine loses 50 percent of its potency in warm conditions in under 1 hour
  81. 81. Causes Of Vaccination Failure / Vaccine • Live vaccines may be inactivated • The vaccine may not contain the proper strains • Poor distribution of live vaccine • Vaccine may be of poor quality Road Map
  82. 82. Causes Of Vaccination Failure / Vaccine • Live vaccines may be inactivated • The vaccine may not contain the proper strains • Poor distribution of live vaccine • Vaccine may be of poor quality Road Map
  83. 83. The Vaccine May Not Contain The Proper Strains  The vaccine may not contain the proper strains or serotypes of organism required to stimulate protective immunity.  Although the vaccine is administered properly and uniform and adequate antibody titers are present, the chickens still break with the disease, particularly with infectious bronchitis and more recently with infectious bursal disease.
  84. 84. Causes Of Vaccination Failure / Vaccine • Live vaccines may be inactivated • The vaccine may not contain the proper strains • Poor distribution of live vaccine • Vaccine may be of poor quality Road Map
  85. 85. Causes Of Vaccination Failure / Vaccine • Live vaccines may be inactivated • The vaccine may not contain the proper strains • Poor distribution of live vaccine • Vaccine may be of poor quality Road Map
  86. 86. Poor Distribution Of Live Vaccine  Poor distribution of live vaccine administered by the water or spray route may result in chickens being "missed" in parts of the house.  Relying on transmission of the vaccine from bird to bird is risky, and can result in excessive rolling-type reactions of long duration and delayed immunity in the flock.  "Misses" with killed vaccines will result in chickens with no protection, as killed vaccines will not spread from bird to bird
  87. 87. Causes Of Vaccination Failure / Vaccine • Live vaccines may be inactivated • The vaccine may not contain the proper strains • Poor distribution of live vaccine • Vaccine may be of poor quality Road Map
  88. 88. Causes Of Vaccination Failure / Vaccine • Live vaccines may be inactivated • The vaccine may not contain the proper strains • Poor distribution of live vaccine • Vaccine may be of poor quality Road Map
  89. 89. Vaccine May Be Of Poor Quality  Vaccine may be of poor quality (low vaccine titer, contaminated, etc.).  The vaccine manufacturing industry is highly regulated and has extensive internal quality control.  Vaccine failure due to problems with the vaccine are rare.
  90. 90. VACCINATION SEROLOGICAL MONITORING
  91. 91. Most Important Serological Tests 1. Hemagglutination Inhibition test (HI). 2. ELISA. 3. Rapid plate agglutination test (RPA). 4. Agar gel precipitation test (AGPT).
  92. 92. Most Important Serological Tests When Conducting Serological monitoring has to know 2 basically things:- 1. What result to expect prior to testing? (Set standards for successful vaccination) 2. What action to take if results are not according expectation?
  93. 93. ELISA Interpretation of vaccination results by ELISA is usually done by evaluating the 3 main key components of immune response after vaccination, which are:-
  94. 94. Intensity of Response (Mean Titer).  Do birds develop sufficient titer levels that are in the expected range for the used vaccine?  These expected titers following vaccination are often called “Baseline Titers”  These Baseline titer values may vary according to type of bird, age, vaccine type, vaccination program and other factors.  Therefore, one should make their own baselines for there own vaccination programs and local conditions.
  95. 95. Uniformity of Response (CV%)  Is the vaccine actually getting to the all birds or not.  The general guidelines for % CV following vaccination are as follows:- % CV Uniformity Less than 30 % Excellent From 30-50 % Good Greater than 50 % Need to Improve
  96. 96. Persistency of Response (Mean Titer response over Time)  Do titers persist long enough over time, or is another vaccination needed to boost titers above minimum protective levels.
  97. 97. Vaccination Baselines Titers in Broiler Test Vaccine Type Mean titer range at 35 - 40 days Suspect Titer Infection NDV -Live, 2x D.W 2000 – 5000 More than 7,000 -Live, 2x Spray 4000 – 8000 More than 10,000 IBV -Live, 1x (H120) 800 – 1500 More than 3,000 -Live, 2x (H120) 2000 – 4000 More than 6,000 IBD -Live, 1x (intmed.) 2500 – 4500 More than 7,000 -Live, 2x (intmed.) 3000 – 6500 More than 9,000
  98. 98. Vaccination Baselines Titers in layers or Breeders:- Test Vaccine Type Mean titer range Wks after Vac. To test NDV -Live (Lasota) 2,000 – 8,000 2 – 3 wks -Inact. 10,000 – 15,000 4 – 7 wks IBV -Live (H120) 2,000 – 4,000 3 – 5 wks -Inact. 6,000 – 17,000 5 – 7 wks IBD -Live (intmed.) 2,500 – 7,000 3 –5 wks -Inact. 7,000 – 12,000 4 – 7 wks

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