Understanding antimicrobial stewardship: Disease severity treatment thresholds and antimicrobial alternatives among organic and conventional calf producers.

Reductions in livestock antimicrobial use (AMU) can be achieved through identification of effective antimicrobial alternatives as well as accurate and stringent identification of cases requiring antimicrobial therapy. Objective measurements of selectivity that incorporate appropriate case definitions are necessary to understand the need and potential for reductions in AMU through judicious use. The objective of this study was to measure selectivity using a novel disease severity treatment threshold for calf diarrhea, and identify predictors of more selective application of antimicrobials among conventional dairy producers.

Associations of various physical and blood analysis variables with experimentally induced Mycoplasma bovis pneumonia in calves.

Objective: To determine associations of blood analysis variables and orbit and nasal planum surface temperatures with the onset and severity of Mycoplasma bovis pneumonia in calves. Animals-28 healthy calves.

Procedures: Calves were challenged with M bovis (n = 24) on day 0 or not challenged (4).

Assessment of a commercially available point-of-care assay for the measurement of bovine cardiac troponin I concentration.

Objective: To assess a commercially available point-of-care assay for measurement of bovine cardiac troponin I (cTnI) concentration in blood and plasma samples.

Sample: Prepared bovine plasma standard samples with known concentrations (0 to 1.0 ng/mL) of cTnI and blood and plasma samples obtained from 28 healthy 2.

Elimination kinetics of chlorhexidine in milk following intramammary infusion to stop lactation in mastitic mammary gland quarters of cows.

Objective: To evaluate the elimination kinetics of chlorhexidine in milk when used as an intramammary infusion to stop lactation in cows.

Design: Prospective study.

Animals: 6 cows.

Serum lactoferrin concentrations in colostrum-fed calves.

Objective: To determine serum lactoferrin concentrations (SLFC) in neonatal calves before and after ingestion of colostrum and to develop models that predict SLFC as a function of colostral lactoferrin concentrations (CLFC) in calves.

Animals: 13 Holstein calves.

Procedure: Calves were fed 4 L of colostrum via oroesophageal feeder within 3 hours after birth.

Evaluation of a commercially available immunoassay for assessing adequacy of passive transfer in calves.

Objective: To evaluate diagnostic utility of a commercially available immunoassay for assessing adequacy of passive transfer of immunity in neonatal calves.

Design: Prospective study.

Animals: 123 calves.

Serum immunoglobulin G concentrations in calves fed fresh colostrum or a colostrum supplement.

This study compared serum immunoglobulin G (IgG) concentrations in calves fed colostrum with those of calves fed a colostrum supplement containing spray-dried serum. Twenty-four Holstein calves were randomly assigned to I of 2 treatment groups (fresh colostrum or colostrum supplement). Each calf was fed 4 L of colostrum (n, = 12) or 4 L of colostrum supplement (n2 = 12) via oroesophageal intubation at 3 hours of age.

Factors related to in-house agricultural animal caseloads in US veterinary teaching hospitals.

A retrospective observational study was conducted to determine whether agricultural animal caseloads at veterinary teaching hospitals declined between 1995 and 1998. Thereafter, the effect of organizational and demographic factors on 1998 in-house agricultural animal caseloads was examined. Caseload data were obtained from the American Association of Veterinary Medical Colleges.