Moro et al., 2000 described an increased antimicrobial drug resistance of Escherichia coli in the intestinal flora of swine as a response to heat stress. This observation was gathered over the course of four studies. Throughout the four studies, finisher pigs (85 kg) were utilized from a common source of swine which had not been supplemented fed antimicrobials for the previous ten years. Animals were randomly selected from a single pen and transported to the research facility 30d prior to the initiation of the studies. During the 30d before the studies, animals were acclimated to 21°C, with ad libitum access to water and fed the same antibiotic-free feed from the source farm. The hypothesis for their study was: an increase in intestinal motility increases shedding of antimicrobial resistant E. coli and that heat stress induces a reduction in intestinal transit time in swine. In order to test these hypotheses, objectives for study were:
Study 1 Finisher pigs (n=10) were randomly allotted to three groups, animals in all groups were subjected to 34°C temperatures (heat stress) and 65% relative humidity for 24hr. Fecal samples were collected weekly prior to the start of treatment and daily during, and for 10d …show more content…
It is unclear whether or not all animals were subjected to the heat stress in those allotments on the same day. There is a lack of a positive control group in this study in which animals were subjected to all collections and 65% relative humidity without the influence of 34°C heat stress. As for the fecal and rectal temperature collection, a daily collection for consecutive days before would provide for a more accurate representation of the baseline for both microbial response and body temperature response to the treatment. The timeline of slaughter post termination of treatment is unclear it is also unclear if anything was sampled post-mortem.