Secondary Trauma in Cage-Free Hens. Frederic J. Hoerr DVM USPEA Live Production, Welfare, and Biosecurity Seminar Nashville, TN September 18, 2018

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1 Secondary Trauma in Cage-Free Hens Frederic J. Hoerr DVM USPEA Live Production, Welfare, and Biosecurity Seminar Nashville, TN September 18, 2018

2 Normal mortality in commercial layers 6.4% to 11.6% to 80 weeks, depending on breed 64,000 to 116,000 hens lost in 1M bird farm At conservative loss of 100 eggs/hen 6.4 to 11.6M eggs Major target for improving welfare and profitability 2

3 Mortality survey examines every bird that dies on a given day Regular surveys establish trends that are important for health and welfare Mortality spikes are often a manifestation of normal mortality Focusing only on spikes in mortality may overlook existing information for prevention or mitigation Assessing mortality 3

4 Mortality survey vs. Normal bird/wellness survey Mortality Survey Primary cause of death General categories not definitive diagnosis Can help focus further investigation Contributing or Additional Findings Parasites, injuries, non-lethal disease conditions Wellness exam Normal hens selected for sacrifice and assessment Weight, feathering, conformation, body condition, reproductive measurements 4

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6 A common problem Reports and spreadsheets that get filed and never analyzed 6

7 Mortality Analytics Design Mortality buckets Cloud-based data and operations Keyboard, stylus, or voice data entry Infinitely expandable database Active and retired/archived flock data always accessible Rapid data analysis Graphs and tables Export to Excel 7

8 Mortality Survey Categories Individual body weight Flock body weight Individual or condition expressed as % of flock body weight Primary cause of mortality Secondary or contributing findings Primary Findings Beak Problem Bone - Skeletal Depletion Coccidiosis Cystic Oviduct - False Layer Decomposed Dehydration Emaciation Gout Gut, Enteritis Gut, Other Liver, Fatty or Hemorrhage Liver, Hepatitis Lung, Pneumonia or Air Sacculitis Lung, Respiratory, Other Omphalitis Other Peritonitis Prolapse Reproductive, Other Salpingitis Septicemia, Systemic Disease Suffocation/Piling Tetany, Metabolic (Calcium) Tracheitis or Tracheal Plug Trauma - Injury Tumor Undetermined Urolithiasis Vaccine Error, Reaction Vent Trauma 8

9 Company Complex Farm Analytics House Flock Housing system Breed Date Age Individual bird tables 9

10 Top Findings: Primary diagnoses 1 month 1 year 10

11 Secondary Findings: Oral ulcers Feed Mill A, Farm A Feed Mill B, Farm B Oral ulcers, presumptive evidence of mycotoxins or other irritating substances in feeds, show similar changes in incidence, regardless of feed mill or farm. This is suggestive that the problem may have a common source in purchased ingredients, or reflect annual variations in feed-associated stresses. 11

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14 Trauma - Injuries Primary and Contributing (Secondary) 14

15 Why focus on trauma? Trauma reflects the interface of the hen with her environment Equipment, handling, behavior Some trauma can be corrected Many hens in aviary systems have chronic lesion of trauma that may contribute to mortality Establish data to address consumer perceptions/misconceptions 15

16 Criteria Trauma as primary diagnosis 3 years of data Broken bones, spur-capture, other wire capture, persecution, vaccine handling injuries Pre-existing trauma diagnosis 1 year of data A significant disease process with evidence chronic pre-existing injury Peritonitis, salpingitis, pneumonia, tetany, gout Likely a contributing factor but trauma alone was not fatal Exceptions: Emaciation and Dehydration If chronic pre-existing trauma present, then Trauma is the primary diagnosis Circumstantial evidence of failure to thrive in the production environment 16

17 Primary Trauma Birds with severe coccidiosis were laying with head in feed trough; likely struck on the back or side of head by steel guard on traveling feeder. 17

18 Examples of fatal and nonfatal trauma Curved keel, likely fractured while flying into roosting perch. Nonfatal and common. Broken clavicle (wishbone), likely from flying into aviary equipment. Nonfatal but the dark red muscle = dehydration. Broken leg, with malunion and scar tissue deposition. Fatal injury over time due to insufficient feed intake. Red muscle = dehydration 18

19 Trauma, healed fractures and emaciated & dehydrated hens

20 Pre-existing injury and emaciation Recorded as Primary Trauma 20

21 Trauma, caught in cage, +/- spur 21

22 Wing with chronic trauma with infected skin and likely deeper involvement of the joint. 22

23 Persecution trauma 23

24 Pre-existing trauma of keel 24

25 Clavicle (wishbone) fractures 25

26 Pre-existing keel trauma and peritonitis 26

27 Pre-existing keel trauma and peritonitis

28 Pre-existing trauma and salpingitis (oviduct inflammation) 28

29 Injury, preexisting, with emaciation and dehydration; recorded as Primary Trauma 29

30 Emaciated & dehydrated; failure to thrive. No other lesion identified 30

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32 Trauma as Primary Diagnosis Secondary Findings: Pre-existing Trauma with Primary Diagnosis 32

33 Pre-existing trauma in aviaries - % affected 33

34 Pre-existing trauma in the aviary by age count 34

35 Pre-existing trauma in the aviary by breed, % affected 35

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38 A sampling of a growing number of studies on keel fractures No difference between free-range siblings and conventional cages Traumatic in origin Bone mass is lower in fractured keels (lower bone breaking threshold) Bone ash, collagen no difference Fleming et al, Brit Poult Sci 2003 Up to 60% affected at 50 weeks, Floor > Cage Petrik et al, Poult Sci 94, 2015 Ramps effective in preventing keel and foot pad problems in non-cage systems Heerkens, et al, Poult Sci 95, 2016 Fracture prevalence increases with age, to 50 weeks and beyond Cages > Floor, until 72 weeks+, then Floor > Cage Brown > White Eusemann, BK, et al, 2018, PLOS one, 38

39 Keel Fractures Floor > Cages Cage > Floor Mike T. Petrik Michele T. Guerin Tina M. Widowski Poultry Science, Volume 94, Issue 4, 1 April 2015, Pages , Eusemann BK, Baulain U, Schrader L, Thöne-Reineke C, Patt A, Petow S (2018) Radiographic examination of keel bone damage in living laying hens of different strains kept in two housing systems. PLoS ONE 13(5): e

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42 % o f M o r ta lity % o f M o r ta lity P r e -E x is tin g T r a u m a - F a r m A P r e -E x is tin g T r a u m a - F a r m s A, B, C S y s te m A S y s te m B 0 S y s te m A S y s te m B A v ia ry S y s te m A v ia ry S y s te m 42

43 Conclusions Regular mortality surveys reveal trauma to be a primary cause of death, Acute fatal trauma Chronic pre-existing trauma is detected along with other primary causes of death Fractures of keel and clavicle are the most common pre-existing lesions of trauma in dead hens examined in surveys Peritonitis > emaciation > pneumonia > prolapse > tetany > salpingitis Pre-existing fractures Have greater occurrence in aviaries than conventional cages Appear in mortality by 35 weeks and continue to 100+ weeks Detected in 7 genetic strains (100%) in aviaries, at 12- to 30% of total mortality Aviary systems may be a significant influence 43

44 Discussion This problem was detected and defined by regular mortality surveys and related extended discussion of findings Data analysis was possible because of a disciplined approach to examining normal mortality Survey method was modified to accommodate pre-existing trauma as contributing factor in mortality Ongoing assessment of Interactive pathogeneses with primary diagnoses (infectious and metabolic) Understanding the influence of aviary design Pullet training and layer management may be mitigation points Breed differences 44

45 END Acknowledgements Steve Taylor Paul Williams Dr. Mark Blakely Dr. Bernie Beckman, Dr. Danielle Botting, Frank Johndrew, Bill Snow Dr. Kelli Jones Mark Tilbury Management and Staff at Midwest Poultry Services LP John Hoerr