Housing Systems for Laboratory Fish

Transcription

1 March , Bergen-Norway Lab Animal Science: Special Focus on Fish Housing Systems for Laboratory Fish Tommaso Sala Customer care Manager Aquatic Line Tecniplast - Italy

2 Contents Laboratory aquatic species Main aquatic housing systems for lab models

3 Laboratory aquatic species The focus ofourdiscussionwillbeon housingsystemsfor vertebrate and freshwater models (zebrafish) As it is clear, the choice of the species drives the type of system to be used

4 Main aquatic housing systems for lab models Facing regulations Keep animals healthy Be reliable Be user friendly and safe Easy to maintain

5 Main aquatic housing systems for lab models Outdoor Indoor

6 Main aquatic housing systems for lab models Main aquatic systems Static Flow through Recirculating

7 Main aquatic housing systems for lab models Static Tropical Aquaria 1905

8 Main aquatic housing systems for lab models Static NORMALLY NOT USED FOR FISH -Obtained using cages dedicated for other lab animal species, mainly rodents - Otherwise called fill and dump tanks - Ideal solution for housing a small colony -They occupied a small space -Scaling -up: managing problems and high costs - Poor water quality

9 Main aquatic housing systems for lab models Static

10 Main aquatic housing systems for lab models Flow through Mainly used for amphibians and sometimes adapted for fish Pay attention to water quality

11 Main aquatic housing systems for lab models Recirculating H2O H2O H2O H2O Main choice for teleost lab fish H2O H2O

12 Main aquatic housing systems for lab models Recirculating GIVE ME A PUMP!

13 Main aquatic housing systems for lab models Recirculating Housing tanks Drain Primary solid removal Chemical filtration Pipes Reservoir Biofilter Pump Secondary solids removal Water Disinfection Water source Schematic representation of a recirculating system for zebrafish

14 Main aquatic housing systems for lab models Recirculating Housing tanks Dimensions Materials Water quality

15 Housing tanks DIMENSIONS Big enough in order not to stress the animals housed in and dedicated to proper experimental needs Which is the best density value? Are there any indications? More than one size, different needs

16 Housing tanks Density Management 5 14 Days = 25 Fry per liter Days = 12 Fry per liter 30 + Days = 6-10 Fish per liter This is optimum This number varies dramatically depending on space and research requirements This will allow for quick growth and reproduction of the lines Systems can handle much higher numbers

17 Housing tanks

18 Housing tanks

19 Housing tanks Sometimes it happens!

20 Housing tanks Grouping Stocking Isolation

21 Housing tanks MATERIALS Plastic vs Glass Easily washable and disinfectable Easily handable and ergonomic

22 Housing tanks

23 Housing tanks WATER QUALITY From the APPENDIX A of ETS 123: All the enclosure should be kept free of fish waste products or All the enclosure should be kept free of fish waste products or uneaten food. If these are allowed to accumulate, water quality and thus fish health will be adversely affected

24 Housing tanks: breeding tanks PC PSU

25 Housing tanks: breeding tanks

26 Main aquatic housing systems for lab models Recirculating Drain Reservoir, water source and drain Recirculatingsystems are not closed ones Reservoir It provides a stock of conditioned water, very important in case of ZF Water source Its quality is essential, check the size in case of RO

27 Water source TAP WATER Be carefull, must be dechlorinated RO WATER Activated carbon is normally used

28 Water source: RO

29 Main aquatic housing systems for lab models Recirculating Primary solid removal Normally called PREFILTRATION and acts in order to remove particles greater than 100 µm Pads Bags

30 Prefiltration

31 Main aquatic housing systems for lab models Recirculating PUMPS External or submerged Back up pumps Attention to noise and vibration

32 Main aquatic housing systems for lab models Recirculating Biofilter It s a device (Bioreactor) to culture microorganism Real Heart of the recirculating systems Living entity Direct consequences on the health status of the animals

33 Biofilter Feeding rate, feed composition, fish metabolic rate and uneaten feed affect tank water quality. The by-products of fish metabolism include carbon dioxide, ammonia-nitrogen compounds and fecal solids. The main purpose of a biofilteris to: - Remove AMMONIA - Remove NITRITE

34 Biofilter Weneedtoreduce the concentrationofthe toxicpart ofthe nitrogen compounds which are dissolved in water Which are the nitrogen compounds dissolved in water in a recirculatingsystem? AMMONIA NITRITE NITRATE NH3/NH4 + NO2 NO3

35 Biofilter TOXICITY Toxicity AMMONIA NITRITE NITRATE 0 Concentration

36 Biofilter RECIRCULATING STATIC

37 Biofilter Advised levels of nitrogen compounds for aquatic organism AMMONIA NH3/NH4 + 0,01 NITRITE NO2 0,2 NITRATE NO3 50 mg/l

38 Biofilter Main problems related to toxic levels of nitrogen compounds AMMONIA Ammoniatoxicityisparticularyproblematicin newlyestablishedrecirculatingsystems, overcrowding containers as well as in shipping containers. Fish suffering from ammonia toxicitymayexhibitbehaviouralabnormalities, suchashyperexcitability, anorexia, reduced growth and increased susceptibility to pathogens. Chronic ammonia toxicity is often associated with hyperplasia of the gill epithelium NITRITE Nitrite toxicityislesscommon in aquariasituationsthanammoniatoxicity, butcan occur simultaneously. Nitrite toxicity is the cause of brown blood disease, in which case methemoglobinproduction bychemicaloxidationofhemeironresultsin haemoglobin incapable of combining with oxygen, thus hypoxia occurs.

39 Biofilter

40 Biofilter NH3 AMMONIA NO2 - NITRITE NO3 - NITRATE O2 O2 Bacteria Bacteria BIOFILTER

41 Biofilter Recirculating systems are not closed systems

42 Biofilter NH /2 O2 Nitrosomonas NO H + + H2O Nitrobacter NO /2 O2 NO3 - Nitrosomonas Nitrobacter

43 Biofilter Nitrosomonas Nitrobacter These bacteria are: - Gram negative Image Width: 3 microns - Aerobic: The aerobic bacteria are organism which get energy from metabolic reactions whichneedsoxygenin ordertotake place

44 Biofilter TAN = Total ammonia nitrogen AMMONIAis the principal nitrogenous waste (Bioproductof protein metabolism) NH3 Unionized form Ammonia NH4 + Ammonium ion UIA is the more TOXIC

45 Biofilter NH3+ H2O <=> NH4 + + OH - Low temperature and low ph High temperature and high ph

46 Biofilter How can we determine the [NH3] in ppmfrom its percentage? 1-Measure TAN, ph and Temperature of your water 2-Use the table to calculate the % of toxic ammonia 3-Divide this number by 100 and multiply by the [TAN]

47 Biofilter Examples 2 1 1) The [TAN] is 1,9 ppm, the ph is 8.0 and the Temperature is 25 C (77 F). From the table we can assume that 5,38 % of the total ammonia is in the toxic NH3 (UIA) form. Therefore, the [NH3] is 1,9 ppmx (5,38: 100) = 0,10 ppmnh3 2) The [TAN] is 1,0 ppm, the ph is 7.0 and the Temperature is 20 C (77 F). From the table we can assume that 0,39 % of the total ammonia is in the toxic NH3 (UIA) form. Therefore, the [NH3] is 1,0 ppm x (0,39 : 100) = 0,004 ppmnh3

48 Biofilter

49 Biofilter Biological filters generally fall into four main types, submerged filters, where the media is always underwater (it may either be stationary or free floating), trickling filters, where the media is surrounded by air and water and is trickled through it, Fluidized bed sand filters and Bead filters

50 Biofilter

51 Biofilter Submerged filters Typically used in standard aquaria Simple waterproof container with media inside Main choice for RAS (recirculating aquaculture system) on a small scale For RAS on a big scale, they are normally too big (large size), with a consequent extremely high weight Modern submerged bed filters are very efficient, have low head loss and are very easy to build and maintain They are oxygen net consumers (high flow and possible aeration if needed)

52 Biofilter

53 Biofilter

54 Biofilter Trickling filters One of oldest type of biological filters (late 1800 s) Water is sprayed over the top of the media and collected underneath it They are not consuming oxygen from water (large air-water interface). Because of this they also work as strippers (CO2 removal)

55 Biofilter Pay attention to good water distribution on top of the media (pressure spray or shallow water distribution pan) Energy can be a problem in case of large installation (pump water on top of the filter)

56 Biofilter Fluidized bed sand filters Regular sand filters (Swimming pool application) are worthless as biofiltersin aquaculture). Biofilmsquickly fill the space between the grains and pressure drop across the filter rises rapidly (Frequent back-washing) A sand filter become fluidized when the velocity of the water flowing through the bed is sufficient to raise the grains of sand up and separate each grain from its neighbors. (Particles are suspended in the water stream)

57 Biofilter Possible problems: Relatively high energy in order to fluidized the bed Pressure regulation: the pressure varies depending on the amount of biofilm on the sand particles Uniformity of water flow: water needs to be distributed across the whole bed Net oxygen consumers

58 Biofilter Floating bed filters The media is floating with a similar density of the water and is moved by airlift convection

59 Biofilter Bead filters Relatively new type of biofilter Vessel partially filled with small plastic beads, once full of water, the beads are floating at the top of the vessel Water flows up through the bed of beads DOUBLE ACTION: Biofiltration and mechanical filtration (Clarification) The beads are small enough to trap most large suspended solids, in addition, the surface of the beads support the growth of a biofilm.

60 Biofilter Needs maintenance: periodically the water flow is shut off and the bed of beads stirred to dislodge the suspended solid. The solid are then settling into the bottom of the vessel from which are drain off. Too frequent washing to remove solids dislodges the biofilmand disrupt the nitrification process. On the contrary if the beads are not washed enough, the solids start to plug the bed. Moreover if not well managed the water flow and pressure drop are not constant. Anyway, for small lightly loaded system are working fine.

61 Biofilter Biofiltration system start-up As a ruleofthumb, PATIENCE iseverythingwhenitcomestosystem start-up (Naturally or Chemically) WEEK % of Total Biomass introduced Total system Biomass % 10% % 20% % 40% % 60% % 80% % 100% During this period is essential a daily check of the N-Compounds

62 Biofilter Animals introduction Natural Bio Activator

63 Biofilter Natural Start introducing animals (A small group) Check the Nitrogen compounds concentration (Ammonia) If TAN will increase over 1/2 ppm, set the WCH at a higher value (e.g. from 10% to 20%) and stop introducing animals If TAN will not increase, consider gradual introduction (This will depend on lots of factors: feeding regime, age, water temperature set, etc..

64 Biofilter Bio-Activator Start introducing the Bio-Activator Follow the proper procedure In order to work properly, animals should be in (food) Normally can save 30% / 40% of the biofilteractivation time Forget to load in one shot the system

65 Biofilter Bio-Activator Check the Nitrogen compounds concentration (Ammonia) If TAN will increase over 1/2 ppm, set the WCH at a higher value (e.g. from 10% to 20%) and stop introducing animals If TAN will not increase, consider gradual introduction (This will depend on lots of factors: feeding regime, age, water temperature set, etc..

66 Main aquatic housing systems for lab models Recirculating Secondary solids removal Source: Fish waste Uneaten food

67 Secondary solids removal Solids: compromise filtration equipment block pipes 70 % of TAN (NH3/NH4+-N)in wastewater is associated with organic solids IT S a CRITICAL POINT IN A RAS

68 Secondary solids removal Cartridge filters Always placed downstream the main recirculating pump They required a powerful pump, could be placed in series of different filter bodies Average filtering capacity µm

69 Secondary solids removal Microscreen filtration Drum filter Is a mechanical and self-cleaning filter No pressure operation The filter is pressured through gravity Modular design with some different drum diameters and different mesh filter sizes ( μm)

70 Secondary solids removal Cartridge filters: easier management with a dedicated by-pass valve

71 Main aquatic housing systems for lab models Recirculating Chemical filtration Action against dissolved organigs in water EssentialtoremoveCl - fromtapwater Activated carbon are used Ifnot acid washed can influencethe ph value

72 Main aquatic housing systems for lab models Recirculating Water Disinfection Action on the total bacterial load recirculating Normally UV lamps are used Preventive action Lamps are not everlasting Maesurementunit: µw/cm 2 /sec

73 UV lamps UV energy penetrates the outer cell membrane, passes through the cell body, and disruptsits DNA, preventing reproduction. UV treatment does not alter water chemically; nothing is being added except energy. These UV power is affected by turbidity. Suspended particles are a problem because microorganisms buried within particles are shielded from the UV light and pass through the unit unaffected. The UV lamp never contacts the water; it is either housed in a quartz glass sleeve inside the water chamber or mounted external to the water which flows through UV transparent Teflon tubes. U V units are most often used in constant flow recirculatingsystems. (View a table that shows the Ultraviolet Dosage Required for 99.9% Destruction of Various Organisms (µws/cm2 at 254 nanometer).

74 UV lamps

75 UV lamps Lamp Replacement UV lamps do not burn out as normal florescent lamps do. Instead, the UV lamps will reduce their intensity to about 60% of a new lamp after about one year of continuous use. When lamps are new, they will generate a dosage level near 60,000 µws/cm2. When the dosage drops to 30,000 µws/cm2 (the minimum dosage needed to effectively kill bacteria) lamps should be replaced. Lamp life will be shortened significantly if the lamp is turned on and off more frequently than once every eight hours. Cleaning As water passes through the UV unit, minerals, debris and other material in the water will deposit out and onto the quartz sleeve. This will limit the penetration of UV rays through the sleeve and into the water. To maintain high clarity, the glass around the lamp must be cleaned regularly. Cleaning frequency depends on the water quality and will be minimal with RO, distilled, or deionized water.

76 Main aquatic housing systems for lab models Recirculating Pipes Water Feed Piping From the pumps, in the plant room, to the fish tanks. This part of the piping works in pressure (min 0.5; max 5 or more bars). Positioning can be done without obstacles in height or fittings angles or numbers of elbows (after calculation of total friction losses). Material: PVC

77 Drain Piping From the fish tanks to the plant room. This Piping works without pressure. Critical positioning related to water levels, fittings, elbows, sockets unions and valves!!! Material: PVC, PP

78 Main aquatic housing systems for lab models Recirculating Housing tanks Drain Primary solid removal Chemical filtration Pipes Reservoir Biofilter Pump Secondary solids removal Water Disinfection Water source Schematic representation of a recirculating system

79 Main aquatic housing systems for lab models Recirculating FOCUS: Small labs or quarantine

80 Main aquatic housing systems for lab models Recirculating Quarantine systems The use of separate quarantine area is the best way to lessen the chance of infecting your system with outside organisms If possible the system should be in a completely separate room The quarantine system should be completely separate from your main housing system This includes: Water Tanks Nets Plugs Cleaning supplies

81 Main aquatic housing systems for lab models Recirculating FOCUS: Small labs or quarantine

82 Main aquatic housing systems for lab models Recirculating FOCUS: Medium - Big labs, flexible approach

83 Main aquatic housing systems for lab models Recirculating FOCUS: Medium -Big labs

84 Main aquatic housing systems for lab models Recirculating 1 floor CS DesignSumps below the racks Plant devices are on moveable platform (pallet) and are not totally customized From to racks racks with zebra Pumps Floor level Biofilter in the sumps (submerged or floating) Compact system, with solids filters, UV and pumps Without pressure gravity drain pressure

85 1 floor CS Design Water reservoir With the reservoir is not necessary the sumps below the racks Plants devices are customized From to racks UV racks with zebra Biofilter Water reservoir Pumps Mec. filters

86 2 floors Design: DIRECT PUMPING TO THE RACKS Pressure is maintained constant at racks levels with electronic power regulation of pumping (frequency control) From 15 racks to 30 Floor 0 racks with zebra 100 % Floor -1 Drum filter Biofilters Pumps UV 100 % Plant room

87 3 floors Design : Water is pumped to a ground water level reservoir and gets into the racks with gravity feed Floor % 20 % Floor 0 racks with zebra Floor -1 Drum filter Biofilters Pumps UV 120 % Plant room

88 Main aquatic housing systems for lab models Recirculating Monitoring and Dosing Not always integrated and provided as standard for lab species housing systems Crucial in the managing of big facilities Important for monitoring the physical and chemical main water quality parameters (ph, Cond and Temperature)

89 Monitoring Easy to understand and manage Essential in case of accreditation Remote alarming(different levels)

90 Automatic Dosing Adding certain substances is absolutely necessary to reconstitute RO water (Which is not a suitable water for housing aquatic species) It helps in keeping as constant as possible some of the main water quality parameters (ph and Cond) Lesslaborassociatedwiththe standard system maintenance Possibility to set and change the parameters easily. Itisnotimportantknowingthe concentration of the solution, it s quicker.

91 Cond 1500 Alarm Accuracy + Set point 1180 Accuracy Alarm - Time (weeks)

92 ph 8,5 Alarm + 7,6 7,5 Accuracy + Set point 7,4 Accuracy - 6,5 Alarm - Time (weeks)

93 Thanks a lot for your attention!