Table 2.

Statistical analysis of fecal sIgA circadian rhythmicity^a

Sex	TCDD (μg/Kg)	Robustness (%)	Values of Pb
Female	0	11.8 ± 0.9	0.29 ± 0.03
	10	9.1 ± 3.2	0.44 ± 0.15
	40	19.3 ± 3.6	0.17 ± 0.06
Male	0	16.1 ± 3.5	0.24 ± 0.10
	10	20.0 ± 7.0	0.31 ± 0.12
	40	15.8 ± 3.9	0.21 ± 0.06

^a Data represent means ± SEM for n = 6 mice per treatment group sampled at 4-hour intervals for 4 days. Statistics were calculated using the Cosinor program [53]

^b Results of F tests to determine if the amplitude of modeled cosine waves is significantly larger than zero, an indication that the cosine fit is meaningful [53]