Fig. 3

Quantitative relationship between genome copies per gram of faeces and oocysts per gram of faeces (OPG). a Relationship between genome copies per gram of faeces and OPG based on 109 non-zero observations from dpi 4 to 10 with Eimeria and the corresponding linear models. The expected number of genome copies for 1 oocyst fully sporulated should be around 8 (8 sporozoites per oocyst, should generate a difference of appox. 10¹, at most). However, we consistently observed higher DNA intensities (of up to approx. 10³ more than OPG) for all but samples from dpi 8 and 9. b Residuals of the model in a ordered by dpi. Filled black circles indicate the mean per dpi. Early in infection, relatively more DNA is observed compared to oocysts, while later in infection it is relatively less. c Relationship between genome copies per gram of faeces and OPG with independent slope and intercept for each infection day (indicated by coloured lines). Positive slopes are only observed late in infection (on dpi 8 and 9) meaning that the number of oocysts partially explains the amount of DNA (only) at those time points. d The same relationship as shown in c using a time and individual demeaned dataset, in which genome copies and OPG were added to the maximum value for each mouse individual and time point before transformation with the common logarithm in order to remove within-individual and within-time-point correlations. As in c this demonstrates a very weak (non-significant) correlation between DNA and oocyst counts when time (and host individual) are considered