title: Clinical, behavioral, and pulmonary changes in calves following inoculation with Mycoplasma bovis.
abstract: OBJECTIVE
  To characterize clinical and behavioral changes in calves following inoculation with Mycoplasma bovis and evaluate relationships between those changes and pulmonary disease.
  
  
  METHODS
  22 healthy Holstein steers.
  
  
  METHODS
  20 calves were inoculated intranasally with < 10(8) CFU or > 10(9) CFU of M bovis. Calves were assigned a clinical illness score (CIS) on a scale of 1 through 4 twice daily on the basis of severity of cough, labored breathing, and lethargy. For each calf, distance traveled and time spent near the waterer, feed bunk, or shelter were determined via a remote location monitoring device. Calves were euthanized and necropsied 22 days after inoculation.
  
  
  RESULTS
  13 calves became clinically ill after challenge inoculation; 3 calves were euthanized within 20 days. Among all calves, consolidation was evident in 0% to 79.9% of the lungs; extent of lung consolidation did not differ between the challenge dose groups. Distance traveled and percentages of time spent in proximity to the feed bunk and shelter were associated with CIS; calves with more severe disease traveled less distance and spent less time at the feed bunk and more time in the shelter. Distance traveled by calves was negatively associated with extent of lung consolidation (< or ≥ 10% of lungs affected); this effect was modified by trial day.
  
  
  CONCLUSIONS
  Following inoculation with M bovis, calf behavior patterns were associated with both CIS and severity of pulmonary disease. Use of behavior monitoring systems may aid in recognition of respiratory tract disease in calves.
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66502, USA. bwhite@vet.ksu.edu
authors.forename: Brad J
authors.initials: BJ
authors.lastname: White
authors.forename: David E
authors.initials: DE
authors.lastname: Anderson
authors.forename: David G
authors.initials: DG
authors.lastname: Renter
authors.forename: Robert L
authors.initials: RL
authors.lastname: Larson
authors.forename: Derek A
authors.initials: DA
authors.lastname: Mosier
authors.forename: Lindsey L
authors.initials: LL
authors.lastname: Kelly
authors.forename: Miles E
authors.initials: ME
authors.lastname: Theurer
authors.forename: Brad D
authors.initials: BD
authors.lastname: Robért
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Walz
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology* / Q000473:pathology; D008168:Lung / Q000473:pathology; D008297:Male; D009175:Mycoplasma Infections / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D045682:Mycoplasma bovis; D018410:Pneumonia, Bacterial / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D013997:Time Factors