Fig 1.
Seasonality in the N. ceranae infection intensity observed from March to October in naturally infected honey bee colonies. Data obtained from measurements conducted on a monthly basis for the first five days of each month from March to October in 2014 and 2015. The dotted line represents a linear regression. Diamond shapes (♦) represent means while error bars indicate standard deviation.
Table 1.
Infection types and intensities in the Nosema spp. infected colonies.
Fig 2.
Changes in the intestinal yeast CFU number per honey bee worker observed from March to October in uninfected and N. ceranae-infected honey bee colonies. Data obtained from measurements conducted on a monthly basis for the first five days of each month from March to October in 2014 and 2015. Different lower case letters indicate significant differences (p < 0.05) between uninfected and N. ceranae-infected colonies (one-way ANOVA was performed separately for each month). Dotted lines represent regression lines. Diamond shapes (♦) represent means while error bars indicate standard deviation.
Table 2.
Spearman’s correlation coefficients between yeast CFU and N. ceranae number of spores. Significant correlations (p < 0.05) are indicated with an asterisk.
Fig 3.
The average N. ceranae infection intensity observed during consecutive days of cage experiments conducted in 2014 and 2015. Data obtained from daily sampling from the second day after the infection (4-day-old workers) to the end of each experiment in 2014 and 2015. Diamond shapes (♦) represent means while error bars indicate standard deviation.
Fig 4.
The average yeast CFU number observed during consecutive days of cage experiments conducted in 2014 and 2015. Data obtained from daily sampling from the second day of workers emerging to the end of each experiment in 2014 and 2015. The arrow (↑) indicates the day of N. ceranae infection. Diamond shapes (♦) represent means while error bars indicate standard deviation.