Fig. 2.

Graphical illustration of colony forming units isolated from Q-/q-uniparous cows after intramammary challenge. Colony forming units logarithmized to the base 10 per milliliter (log (CFU/ml)) of bacteria isolated from sterile milk samples of infected udder quarters after intramammary challenge with (a) Staphylococcus aureus (Q: n = 12 versus q: n = 12) and (b) Escherichia coli (Q: n = 6 versus q: n = 6) is shown. The first sample was taken before intramammary challenge and defined as 0 h relative to challenge. Afterwards, quarter milk samples were taken every 12 h. Data are presented as the mean and standard error of the mean (a) and as the median and interquartile range (b). Differences between uniparous cows selected for favorable (Q) and unfavorable (q) haplotypes are indicated with * if P < 0.05 and with ** if P < 0.01. Significant differences within the haplotype groups over time relative to challenge are not shown