1 / 33

Ketone and NEFA testing as diagnostic tools in assessing transition dairy cows

Ketone and NEFA testing as diagnostic tools in assessing transition dairy cows. Stephen LeBlanc OABP/OABA meeting April 14, 2005. Monitoring Programs for Transition Cows. Monitor Current Transition Cow Program HERD LEVEL Track success and compliance with existing program

webb
Download Presentation

Ketone and NEFA testing as diagnostic tools in assessing transition dairy cows

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Ketone and NEFA testing as diagnostic tools in assessing transition dairy cows Stephen LeBlanc OABP/OABA meeting April 14, 2005

  2. Monitoring Programs for Transition Cows • Monitor Current Transition Cow Program • HERD LEVEL • Track success and compliance with existing program • Early detection of problems • Monitor for Subclinical Disease - INDIVIDUAL LEVEL • Early treatment to prevent clinical disease • Helps to quantify problems and direct investigation

  3. Options for Monitoring or Investigating • Clinical disease incidence • Milk production • DMI • Why doesn’t it get done?? • Group average; distribution within group • Target > 12 kg DMI average in close-up (heifers & cows; 3 weeks before due) • Fresh group • Metabolic tests

  4. Daily Dry Matter Intake Around Calving CALVING *

  5. NEFA Propionate AA Glycerol Gluconeo- genesis Completely oxidized  energy BHB Acetoacetate Acetone Incompletely oxidized ketones Glucose Re-esterified  triglyceride Fetus Mammary gland Stored in liver Exported in VLDL

  6. Unsuccessful response to NEB – Ketosis and Fatty liver NEFA Propionate AA Gluconeo- genesis Completely oxidized  energy BHB Acetoacetate Acetone Incompletely oxidized ketones Glucose Re-esterified  triglyceride Fetus Mammary gland Stored in liver  Exported in VLDL

  7. Typical patterns of DMI and NEFA Overton/Burhans, 2001

  8. Associations with health and performance • Pre-partum NEFA associated with: • ~ 4X increased risk of LDA (Cameron et al, 1998; LeBlanc et al, 2005) • ~ 1.5X increased risk of RP (Dyk, 1995; LeBlanc et al, 2004) • 2 – 3 X increased risk of subclinical ketosis (Osborne, 2003; Gooijer et al, 2004)

  9. Incidence of Subclinical Ketosis Median time to diagnosis of clinical ketosis = 11 DIM Duffield, 2000

  10. Prevalence of Subclinical Ketosis Oetzel, 2003 Duffield et al 1998

  11. Clinical ketosis treatment rate is a poor estimate of ketosis (Duffield et al 1998)

  12. Associations with health and performance • BHB (subclinical ketosis) in early lactation is associated with: • 4-8X increased risk of LDA (Geishauser, 2000; LeBlanc et al, 2005) • Decreased milk production (Duffield, 2000) • Increased severity of mastitis (Suriyasathaporn et al, 2000) • 50% decrease in pregnancy at first AI (Walsh et al, 2004)

  13. Effect of subclinical ketosis in week 2 on CR at 1st AI (Walsh et al, 2004)

  14. Milk Keto-Test 100 µmol/L Sensitivity = 83% Specificity = 82% 200 µmol/L Sensitivity = 54% Specificity = 94% Oetzel, 2004 Powder lacks sensitivity Urine Ketostix (read at 5 seconds) “small” (15µmol/L) Sensitivity = 79% Specificity = 96% Carrier et al, 2004 Acetest tablet lacks specificity Cow-side tests for ketosis(relative to serum BHB ≥1400 µmol/L)

  15. Subclinical Ketosis Monitoring Programs(True Prevalence = 20%)

  16. Sampling logistics • In a herd with 50 to 1000 cows, if a prevalence of “positive” tests • e.g. NEFA ≥ 0.5 or BHB ≥ 1400 • And ≥ 10% is the threshold of interest • And you wish to be 75% confident of detecting this level of problem, then… • 13 samples are required • Oetzel proposes using 12 samples for NEFA and BHB blood testing for investigations

  17. Metabolic Predictors of LDA • 1184 animals in 20 herds • Weekly visit by technician • Same day, same time (AM) • Cows enrolled 4 - 10 d prior to expected calving • Sampled weekly until the week after calving (Total of 2 - 4 samples) LeBlanc et al, 2005

  18. LeBlanc et al, 2005

  19. LeBlanc et al, 2005

  20. Prepartum DA model • Among all variables measured in last week before calving: OR95% CIP NEFA  0.5 mEq/L 3.5 1.9 – 7.1 .0001 Sensitivity = 64% Specificity = 66% LeBlanc et al, 2005

  21. Simple Association of NEFA 4-10 d before DUE with LDA LeBlanc et al, 2005

  22. Simple Association of NEFA 4-10 d before DUE with LDA * Excluding cows within 2 days of actual calving LeBlanc et al, 2005

  23. Postpartum DA model Minimum significant cut-points in the model: BHB  1000 mol/L ; NEFA  0.6 mEq/L LeBlanc et al, 2005

  24. Postpartum Simple Associations with DA LeBlanc et al, 2005

  25. Postpartum Simple Associations with DA LeBlanc et al, 2005

  26. Sample handling • Serum (red top) or plasma (purple top) • Avoid hemolysis • Ideal: keep chilled, separate within a few hours, ship chilled to arrive at lab in 1-2 days • Serum can be frozen for at least 1 month • What you could get away with: delay of < 24 h to separate; serum at room temp for < 24 h or in fridge for < 3 days (Stokol & Nydam, 2004)

  27. Monitoring Energy Metabolism in Transition Cows • Pre-Calving - NEFA • Post-Calving - Ketones • Routine monitoring (milk or urine)

  28. Monitoring Energy Metabolism in Transition Cows • Helps to direct investigation • What is the problem? • Where/when is the problem? • Rarely answers “WHY?” • Need to look further and test hypotheses

  29. Evaluation of a Rapid, On-Site Serum NEFA Test • 10 Guelph-area farms • Prepartum blood sample • (-7 to –4 days) • Harvested serum and aliquoted • Measure NEFA concentrations: • Animal Health Laboratory (Hitachi 911 analyzer) • DVM NEFA Gooijer et al, ICPD 2004

  30. Correlation between tests Pearson’s r = 0.89 Gooijer et al, ICPD 2004

  31. Test Characteristics of DVM NEFA (Gold Standard = AHL > 0.4 mEq/L) Sensitivity = 84% Specificity = 96% Gooijer et al, ICPD 2004

  32. Fresh feed daily Adequate bunk space (>60 cm) > 100 ft2/cow of pack < 100% stocking Separate heifer groups Moderate BCS (3.5) Adaptation to new rations (3-4 weeks) Adequate eNDF Minimize group/pen changes Heat abatement THI > 72 T > 27 C Free choice water 0.5 – 0.75% BW in concentrates 60:40 Forage:concentrate Rumensin CRC Maintaining Peripartum DMI

More Related