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Pink Eye

Pink Eye. James Reecy Annette O’Connor Abebe Hassen Gary Snowder. Pink Eye. Reported in the USA since 1889 45% of Missouri herds have endemic IBK Average prevalence = 8% More common in the young – 10-60% Immunity develops with age No gender affinity.

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Pink Eye

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  1. Pink Eye James Reecy Annette O’Connor Abebe Hassen Gary Snowder

  2. Pink Eye • Reported in the USA since 1889 • 45% of Missouri herds have endemic IBK • Average prevalence = 8% • More common in the young – 10-60% • Immunity develops with age • No gender affinity

  3. How Effective Are We At Controlling Pink Eye? • Kansas ranchers reported it as the 2nd most common infectious disease in 1993 • NAHMS : diseases with economic impact • Internal/ external parasites (way in front) • Open cows • Pink eye • Foot rot • Between 17 and 65 lbs decrease in weaning weight • $150 million yearly

  4. General Information • What causes “pink eye” • Moraxella bovis, ……, is considered to be the cause of IBK” • Gellatt “ food animal ophthalmology” page 1131

  5. What Causes “Pink Eye” • Moraxella bovis • Brannamella ovis? • High UV light • Dust • IBR infection • IBR vaccination • Mycoplasma infection Mycoplasma bovoculi • Trauma • Face flies- Musca autumnalis (since 1946)

  6. What Causes “Pink Eye”? M. Bovis UV Light Long Grass Stress

  7. What Causes “Pink Eye”? M. Bovis UV Light Face Flies

  8. Why Do Only Some Calves Get Pink Eye? • Individual differences • Genetics • Dam colostral immunity

  9. Options For Control/ Prevention • Remove reservoirs for M.bovis • Cattle ( sub-clinical carriers) • Face Flies, Stable Flies, Horn Flies ( for 3-4 days) • Wildlife ?

  10. Options For Control/ Prevention • Are the technologies up to the job?

  11. Options For Control/ Prevention • Not up to the job • Vaccines • Fly control • Dust control • Pasture clipping

  12. Options For Control/ Prevention • Vaccines: • Pilated forms of M bovis are virulent – allows attachment • At last count there were 7-8 pili groups, they do not provide much cross protection • Each pilis type is associated with specific ab production • Failure in vaccines is due to low cross protection and emergence of new pili. • Also naturally animals produce lacrimal IgA to M bovis, vaccines stimulate serum IgG, IgM, and secretory IgA

  13. Why Does Control/ Prevention Fail? • Fly control • Adulticides, traps, larvicide's rarely achieve > 50% control • Due to small amount of time spent on animal • At any one time , < 5% of the entire female population ( only females) on cattle • Overlapping generations means that traps don’t work • Local migration is easy – they moved from Nova Scotia to in 1950’s to North Dakota in 1960: renewing populations constantly

  14. What The Future Options • Genetic selection • Improved vaccines • Better treatment

  15. Assumptions • Genetic variation in resistance/ susceptibility to the pinkeye exists • Low heritability (<.15) • Disease incidence is low ~10%

  16. Requirements of the project • Serve as a model for disease resistance/susceptibility research • Internal parasites - nematodes • Respiratory • Use field records • Need to develop data collection scheme • Need ~8,000 records

  17. Data Collection • Two seasons • When cases are actively observed • Weaning • Scoring system • Data sheets

  18. ACTIVE LESIONS: SHEET 2 Score 1 – An active lesion involving less than one-third of the cornea. Score 2 – An active lesion involving one-third to two-thirds of the cornea.

  19. Score 3 – An active lesion involving more than two-thirds of the cornea. Score 4 – An active lesion with perforation of the cornea

  20. Current data collection • Iowa State – Rhodes Research Farm • American Angus Association • Contacted a few breeders to start collecting data • Iowa, Missouri, Indiana, Wisconsin • Universities • Ohio State • Kentucky

  21. Change in Severity Over Time October Severity Call August Severity Call

  22. October Severity Call Right August Severity Call Left

  23. Data Analysis • No sex or eye effect • Heritability • MTDFREML • Model Y =  + CG +animal +PE + error • CG = Sex-weaning group (4) • PE = permanent environmental • h2 = 0.18

  24. MARC Pinkeye data • Gary Snowder • 19 years of data • Calves listed as being treated in the herd book • Number of records • 907 to 10,947 head per breed • 1.3 to 22.4% incidence

  25. Future Direction • Moraxella bovis infection rate vs. Corneal abrasion • Field data collection • Mechanism?

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