Anti-microbial usage and Expectations. Gerald Stokka, DVM, MS Livestock Stewardship

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1 Anti-microbial usage and Expectations Gerald Stokka, DVM, MS Livestock Stewardship

2 WHAT DOES A PULL LOOK LIKE?

3 Signs of Disease Everything is respiratory disease Difficult to distinguish from other conditions Acidosis vs Pneumonia

4 Feedlot Cowboy BRD Diagnosis What Does a Pull look like? Depression Low head set Continue lying down when penmates rise Standing alone, avoiding pen activity Anorexia May come to the bunk, not eat Gauntness (high in the flank) No bowel movement after standing up

5 Feedlot Cowboy BRD Diagnosis Weakness Knuckling Floppy walking Standing or walking Cross-legged Downers Weakness is likely due to negative energy balance, and the development of ketosis.

6 Feedlot Cowboy BRD Diagnosis Nasal Discharge Clear moisture inside the nares is normal. Color o Clear ropy nasal discharge usually indicates an URT irritant or URT viral involvement. o Purulent (yellow or green) nasal discharge indicates bacterial involvement (sinusitis). Time of Day o Nasal discharge early in the morning is normal. o Excessive discharge after feeding is abnormal.

7 Feedlot Cowboy BRD Diagnosis Cough Coughing is a normal function and may be present without pathology. Soft moist cough is common with BRD. Usually indicates tracheal irritation Poor air quality o Dust o Diesel Fumes Infectious Disease o BHV-1 (IBR)

8 Feedlot Cowboy BRD Diagnosis Cough May be of lung origin Bovine Respiratory Syncytial Virus (BRSV) Mycoplasma Emphysema Ruptured lung abscess Chronic BRD

9 BRD Diagnosis 35% of calves received treatment for respiratory tract disease between birth and slaughter. However, 72% of all calves had lung lesions at slaughter. 78% of calves treated for respiratory disease had pulmonary lesions. (22% false positives) 68% of calves that were never diagnosed or treated for respiratory disease had lung lesions at slaughter. (false negatives) Wittum, et al

10 Principles of Therapy Above all, Do no harm Hippocrates

11 ATTRIBUTES OF THERAPEUTIC PRODUCTS Clinically Efficacious (as per label) FDA Approved Preserve Beef Quality (SQ. options) Preferably Low volume

12 Antibiotic Therapy Antibiotic - chemical substances produced by various species of microorganisms (bacteria, fungi, actinomycetes) that suppress the growth of other microorganisms and may eventually destroy them.

13 Percent resistant Ceftiofur Enrofloxacin Florfenicol Oxytetracycline Spectinomyci n Tilmicosin % 29.1% 29.1% 56.4% 36.4% 45.5% % 47.1% 36.1% 64.5% 51.6% 47.1% % 63.1% 43.0% 81.0% 63.7% 61.5% Number of Isolates by year

14 Culture and Sensitivity Most cultures are from dead animals Treated Does not seem to correlate directly with treatment success Other factors than antibiotic sensitivity contribute to treatment success.

15 Treatment Response

16 Treatment Response Factors Age/Quality of Cattle Procurement Shipping Stress Pathogens Processing Program Nutrition/TLC Bio-containment

17 Treatment Response Factors Immune status Stage of disease/crew attitude and capability Therapeutic regimen

18 Treatment Response Fever reduction, attitude, feed consumption, hydration status!!! Mortality Retreats, repulls Treatment cost

19 Treatment Success Response rates in the same yard using the same treatments range from 55% to 86% to first treatment. Differences were not due to antibiotic failure, but calves in lower response group were lower priced, and took longer to assemble. R.A. Smith, Bovine Respiratory Disease, Sourcebook for the Veterinary Professional,1996

20 Therapy 1150 calves, average weight 552, Southeastern origin, multiple salebarns and order buyers. 52% pull rate, 3.1% mortality, 5.9% case fatality rate. Northern bawling commingled calves <15% morbidity <1% mortality <5% case fatality rate

21 Cost of Illness T1 & T2 Combined performance data Sick Well 313 head 857 head ADG Decatur Select Vac Study, Illness reduced ADG by 0.4 lbs/head/ day across treatments

22 Cost of illness To calculate the cost of illness in a load of calves that has a 10% diagnosed sickness rate and a 5% case fatality rate; 10% * $0.90 (value of gain) * 0.4lb/hd/day (loss of performance) * 90 (days on feed) = $3.24 $30 treatment cost *10% = $3.00 $10 processing cost *100% = $ % morbid *5% case chronic rate *$1020/2 (1/2 purchase price) = $ % morbid * 5% case fatality rate * $1020 (purchase price) = $5.10 Total $23.89

23 Cost of Illness How much would a 600 animal need to be discounted to make up this cost in expected morbidity, performance loss, chronics and deads. $23.89/600 = $0.04/pound. $23.89/200 lb of gain = $0.12/lb decrease value of gain, now value of gain is only $0.78/lb.

24 Baytril vs. Micotil vs. Nuflor Item Baytril Micotil Nuflor Mortality % Chronics % Relapse rate % ADG (60 days) No. calves 1443 Avg in weight range 475 Colorado to 642 Kansas Bayer 2000

25 Antibiotics and Medications Treatment regimes shall follow label directions unless otherwise directed by a veterinarian. Extra label drug use shall be used only when prescribed by a veterinarian with a valid VCPR.

26 Combination Therapies Reasons for combinations Broaden spectrum? Suppress resistance? Kitchen sink approach

27 Treatment Schedule Diagnosis Treatment Dosage Route Withdrawal RESPIRATORY SYSTEM: Respiratory, Acute Advocin( ) 1.5cc/100 cwt repeat 48 hrs S.Q. 4 Days Second Treatment Nuflor ( ) Banamine( ) 6cc/100 cwt 1cc/100 cwt S.Q. I.V. 38 Days Respiratory Chronic Diphtheria LA-200 Tylan Predef 2X ( ) Excenel ( ) Predef 2X ) 5cc/100 for 3 days 4cc/100 for 3 days 5cc/Animal for 1 day 2cc/100 for 3 days 5cc/Animal for 1 day I.V. I.V. S.Q. S.Q. S.Q. 42 Days 30 Days The above products are being utilized in treatment schedules. Directions for their use and withdrawal times have been reviewed and are posted Manager Prescribed by Date License No.

28 Summary Priorities for Success Disease Prevention Source Management Metaphylaxis Vaccination Early Recognition and Treatment of BRD Effective Therapy (antibiotic selection) TLC