Stanton PhD Thesis final_docx - Atrium - University of Guelph

treatment and weight gain category. Bunk behaviors were observed for the last 65 calves on the
trial, and resting behaviors were observed for the last 44 calves on the trial (Table 3.1). Smaller
sample sizes were based on the availability of video tapes with earlier groups not recorded. Bunk
engaged was use to determine if calves stood at the feed bunk but did not consume feed. Bunk
directed behavior was used as an indicator of reluctance to place the head through the stanchion,
which is potential inhibitor of feed intake. Close and Far Lying were used as measurements of
affiliation. One group of 5 calves was excluded from the study of bunk behaviors due to the
failure of video recording equipment.
3.2.2 Experimental Study Design
The objective of the underlying trial was to identify behavioral and physiological changes
associated with bovine respiratory disease complex (BRD) or administration of a long-acting
antibiotic. No calves were diagnosed with BRD in the first week post-weaning. On days 0, 4, 7,
11 and 14 of the present study calves were haltered and blood samples were collected via jugular
venipuncture for measures associated with the antibiotic trial.
3.2.3. Statistical Analysis
All statistical analyses were conducted using Statistical Analysis Software (SAS version
9.1; SAS Institute Inc, Cary, NC, USA).
Means and standard errors for each weight gain category were generated for normally
distributed continuous variables (Proc Means). If the variables were not normally distributed
upon visual assessment, medians were presented with a range for the 1 st and third quartiles (Proc
Means).
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