Production Practices of Successful Catfish Producers

Transcription

1 Production Practices of Successful Catfish Producers Jimmy Avery, Ph.D. Extension Aquaculture Leader National Warmwater Aquaculture Center Mississippi State University

2 Contributors Dr. James Steeby, NWAC Dr. Craig Tucker, NWAC Charlie Hogue, NWAC Dr. Les Torrans, USDA CGRU Paul Dees, Dillard Farms Keith King, Dillard Farms Brent Johnson, Aqua Farms, Inc.

3 US Catfish Acreage , , , , , , ,100 Acres 150, , , USDA NASS

4 US Catfish Acreage , , , , , ,100-15% 158,100 Acres 150, , , USDA NASS

5 Reasons for Loss of Farms Record low fish prices for 30 months Rising input costs (feed, equipment) Import competition Increased indebtedness Failure to reinvest in infrastructure

6 Reasons for Loss of Farms Record low fish prices for 30 months Rising input costs (feed, equipment) Import competition Increased indebtedness Failure to reinvest in infrastructure Many were excellent farmers!

7 Catfish Price Recovery 75 $ Cents / Lb $ 0.70 $ Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

8 Current Challenges Rising input costs (fuel, labor) Domestic competition from other protein sources Import competition Tightening foodfish supplies Projected shortage of fingerlings Increasing disease losses Decreasing production levels on many farms

9 Limits of Catfish Production Limitations Maximum Potential Water Temperature Year Round Demand Infectious Disease Bird Depredation Dissolved Oxygen Off-flavor flavor Impact (% Decrease) - 50% 20% 20% 10% 22% 15% Production (lbs/acre) 30,000 15,000 12,000 9,600 8,640 6,740 5,728

10 Management Implications Few of the limitations are manageable Water temps uneconomical Year round demand market driven Infectious disease problematic, increasing Bird depredation difficult to negate Dissolved oxygen feasible, expensive Off-flavor flavor feasible

11 Management Implications Few of the limitations are manageable Water temps uneconomical Year round demand market driven Infectious disease problematic, increasing Bird depredation difficult to negate Dissolved oxygen feasible, expensive Off-flavor flavor feasible Will max yield = max profit??

12 Management Implications Reduce the Cost of Production There is rarely one area where significant cost reductions can be attained. The more profitable businesses manage many costs 2-5% 2 more efficiently than their competitors.

13 Developing a Farm Plan

14 Components of the Plan Financial Investing in proven strategies Booking feed (amount vs. protein) Production Minimize time in pond Marketing Sell fish based on size and flavor; not price Personnel Strategic Maintenance (equipment & ponds)

15 Pond Maintenance

16 Pond aging reduces useable pond volume New Pond Old Pond Erosion 3 ft 1.25 ft Year ft water Sediment

17 Sediment Accumulation Caused by: Erosion from pond levees Aerators gouge sediments from bottom Very little accumulation is waste products Management implications Harvest difficulty Decreased production (higher FCRs) Increased aeration

18 Pond Rebuilding After years, start rebuilding 10% of ponds each year Build ponds with a 6 ft average water depth Deeper ponds are more expensive to construct but have a longer useful file Drain shallow ponds every 3 years or use them for fingerling ponds Making pond levees wider will not affect the sediment accumulation

19 Improving FCRs

20 Feed Conversion Ratio (FCR) Individual Pond (Biological FCR) Possible in batch culture (ex. fingerlings) May be based on multiple months Whole Farm (Economic FCR) Pounds of Feed fed : Pounds of Fish sold Based on assumption that beginning and carryover inventory are rather constant from year to year Based on a single year

21 Biological FCR Unlikely to match on commercial scale unless accounting for losses Not much size variation until you get over 3 pounds Fish Size 0.75 lb 1.25 lb 2.0 lb 5.0 lb FCR Robinson & Li

22 Economic FCR Primary determinant on profits Even well performing farms operate in the 2.3 to 2.5 range Decrease by 0.1 unit results in a savings of about $50/acre/year

23 Improving FCRs Three Primary Influences Mortality Feeding Practices Depredation

24 Minimizing Mortalities

25 Proactive Fish Health Management Be aware of losses and trends Minimize the amount of stress and physical injury to fish Maintain adequate chloride levels and aeration Submit fish sample to verify diagnosis Consider the economics of action and non- action

26 Proactive Fish Health Management Check fish for clinical signs (trematodes, etc.) whenever they are being seined or transported If economically justified, initiate treatments before disease intensification or reduction of feed intake

27 Treatment Considerations Must consider: Cost effectiveness (losses vs. expense) Probability of subsequent outbreak (temperature window) Ability to treat targeted fish (mixed sizes) Diagnosis (mixed infections)

28 Restricted Feeding Regime Research indicates that restricting feed during an ESC outbreak reduces mortality Based on temperature or onset of losses Cessation or alternate day feeding of non- medicated feed

29 Medicated Feeds Medication options: Romet (5-d d treat, 3-d 3 d wd) Terramycin (10-d d treat, 21-d d wd) Aquaflor (10-d d treat, 12-d d wd) Veterinary Feed Directive Drug Licensed Vet must write order 2 year record requirement

30 Vaccines AQUAVAC-ESC does appear to increase resistance to ESC Results have been somewhat variable Expensive Must be able to justify costs Protection is not absolute, must be viewed as a tool to help control infection

31 Monitoring Water Quality

32 Ammonia Low in summer (0.5 ppm TAN) Increases through fall (4-5 5 ppm TAN) Peak mid-october (5-6 6 weeks after peak feeding) Nitrite concentrations peak weeks after peak ammonia concentrations

33 Ammonia and Nitrite NITRITE TAN /21 9/21 10/21 11/21

34 Ammonia Management Little or no practical short-term term management options available More practical to take preventive approach Reasonable stocking rates Harvest often as practical to avoid excessively high standing crop of fish Use good feeding practices Moderate rates Be sure all feed offered is consumed

35 Monitoring Ammonia Only reason to monitor is to predict potential nitrite problems Monitor every other day following a bloom crash Monitor weekly during cooler months Otherwise, not necessary

36 Nitrite TAN converted to NO 2 (nitrite) NO 2 normally converted to NO 3 (nitrate) Disruption in cycle leads to buildup of NO 2 Causes Brown Blood disease More frequent in fall and spring

37 Nitrite Management Chlorides in water prevents uptake across the gill membrane Common salt (NaCl( NaCl) ) is cheapest source Maintain at least 10:1 ratio of chlorides to nitrites Some prefer 20:1 ratio General rule: ppm chlorides

38 Cl - Water Cl - Cl - NO - 2 Cl - Cl - Cl - Cl - Cl - 10:1 chloride nitrite ratio Low probability of NO2 - Binding to receptor Cl - Cl - Cl - Blood Cl - Cl - Cl - Cl - Cl - Cl - Cl - Cl - Cl - Cl - NO - 2 Cl - Cl - Cl -

39 Monitoring Nitrite August: Measure chloride levels and add salt to 100 ppm in all ponds Begin measuring NO 2 weekly beginning in mid-october Re-check chloride levels when NO 2 is elevated or flushing has occurred Check NO 2 daily if Cl:NO 2 ratio approaches 10:1

40 Increasing Available Aeration Levee Pond Average = 1 hp/acre Recommended level = 2 hp/acre Higher Production = 3-6 hp/acre

41 Raising Minimum DO Intensification made possible by increased aeration Variation among farms concerning when aeration is initiated Begin at 5 ppm, maintain ppm Begin at 2 ppm Begin when fish show stress

42 Research Results Production Parameter Feed Consumption Net Production Aeration Hours Harvest Weight FCR Survival 5.0 ppm 100% 100% 100% 100% Aeration Target 2.5 ppm 93.7% 100% 38% 100% (No difference) (No difference) 1.5 ppm 54.9% 46.0% 16% 69.5% L. Torrans

43 Conclusions Delaying aeration until 2.5 ppm DO had little impact on production Delaying aeration until 1.5 ppm DO decreased most production parameters by at least 30% If feed is consumed, it will be converted similarly among a range of DOs Results may not be extrapolated directly to large commercial ponds L. Torrans

44 Refining Feeding Practices

45 Importance of Feeder Has direct control of 50% of operating costs Must be able to spend the time necessary to feed properly Must communicate with others concerning fish behavior

46 Feeding Practices Comments refer to feeding healthy fish, 4-55 inches and up If fish eat it (and live), they will convert it efficiently Recommendations are to be considered as guidelines No single method optimum Robinson and Li

47 Feeding Practices 28% protein feed with 3% or less animal protein Feed to satiation in a single, daily feeding May offer second feeding to fish that fed extremely well (avoid wasting feed) No difference in time of day to feed except logistics and avoiding peak oxygen demand Robinson and Li

48 Feeding Practices Feed over as wide an area as possible (40-50% may not respond when fed along one levee) Winter feeding can be beneficial (especially in fingerlings), feed based on temperature Avoid wasting feed Robinson and Li

49 Reducing Depredation

50 Bird Depredation Develop an Active Plan Match resources with estimated losses Estimated $7.1 million for cormorants Seek assistance from USDA Wildlife Services (permits & roost dispersal) Cooperate with area producers in permitted harassment Stay vigilant

51 Bird Depredation Erect Exclusion Devices Effective against cormorants Posts every 60 feet #12 untarred string, feet above water Orange flagging every 15 feet $100 for a 10-acre pond Easily removed for harvest

52 Bird Depredation Consolidate Ponds Cluster fingerling and stocker ponds closer to high traffic areas Consider modular cropping system to keep vulnerable fish out of foodfish ponds

53 Inventory Assessment

54 Inventory Assessment FISHY 2005 Computer software available from CFA Improved reports including NASS output Easily customized for feeding and mortality Spreadsheets MS Excel

55 Inventory Assessment Ground proof computer projections Communicate pond side observations with computer analyst Accurate weights and counts on harvest and stocking Use realistic loss projections Suggest 1.5 2% each month in addition to observed catastrophic losses Zeroing Ponds Out

56 Switching to Modular System large fingerlings stocked Single batch - large fingerlings stocked once per year small fingerlings stocked at high rates or at various times Multiple batch - small fingerlings stocked fry to fingerlings, fingerlings to stockers, and stockers placed into foodfish ponds Modular system - fry to fingerlings,

57 Multiple-batch Production Growout Pond Fingerlings Modular Production Fingerlings Stockers (6 mo) Growout Pond (7 mo)

58 Switching to Modular System Economics of multiple-batch systems becomes more tenuous with processors desire for increased size of harvested product (1.5 to 2.0 lb) More opportunity for proactive fish health management due to similar size fish Stockers for final growout phase exceed size that is commonly susceptible to bird depredation

59 Research Results 50,000/A Diet Mean Weight Survival Production (% Protein) (lb) (%) (lb/a) 2005* 2004** , , ,516 *Stocked 32 lb/1000 fingerlings **Stocked 22 lb/1000 fingerlings 180-day growout Fed to satiation L.R. D Abramo. D 2005.

60 Switching to Modular System Better water quality in foodfish ponds due to lower stocking rates (4,500 5,500) Less deductions due to out-of of-specification fish size

61 Switching to Modular System Better water quality in foodfish ponds due to lower stocking rates Less deductions due to out-of-specification fish size Better control of inventory (No surprises!)

62 Minimizing Off-flavor flavor Delays

63 Off-flavor flavor Sporadic, unpredictable flavor taints from odorous water-borne compounds Adds at least 5 cents per pound to production cost $30 million impact per year

64 Off-flavor flavor Management Copper sulfate treatments Diuron treatments (where allowed) Time!!

65 Copper Sulfate Treatment Developed for use in moderately hard waters typical of the MS Delta region ( ppm) 5 pounds / acre / week when water temperatures are above 70 F Crystals in double burlap bag placed feet in front of paddlewheel aerator till completely dissolved (2-3 3 hours)

66 Copper Sulfate Treatment Results of 3-year 3 on-farm trial 50% reduction in the number of all off-flavor flavor episodes and 75% reduction in the number of MIB episodes 85% reduction in the duration of off-flavor flavor episodes About $3.50/acre per week treatment cost

67 Copper Sulfate Treatment Results of 3-year 3 on-farm trial 17% increase in hours of emergency aeration Increased levels of total ammonia and nitrite, although concentrations never increased to dangerous levels

68 Diuron Treatment 0.5 ounces of 80WP / acre-foot Apply weekly until fish are on-flavor A maximum of 9 applications / year Slurry applied into aerator current Treat only when water temperatures are above 70 F

69 Diuron Treatment Producer surveys indicated that farmers rated diuron moderately to highly effective Processor surveys show a decreased percentage of non-acceptable fish since diuron was approved for use

70 Effective Use of Algicides Algicides do not work on off-flavors flavors that are not caused by algae Algicides are ineffective at water temps below F Initiate fall treatments to reduce off-flavors flavors in fish scheduled for harvest in winter

71 Effective Use of Algicides If fish are off-flavor, flavor, considerable time will be required for then to clean up Time for algicide to work Time for fish to purge the odorous chemical The time required to clean up varies with water temperature In warm water, weeks is an optimistic guess So plan ahead

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73 Questions?