Fig. 2: Testosterone and estradiol plasma profiles maturate similarly in wild-type (AR^+/+), heterozygous (AR^+/−), and homozygous (AR^−/−) juveniles while development of testicle size, egg-laying and weight of bursa of Fabricius is impacted in AR^−/− chickens.

We depict plasma levels (pg/ml) in males and females and from 1 to 20 weeks after hatching (for all groups n ≥ 3, Supplementary Table S3 or Source Data file), corresponding to sexual maturity. At 20 weeks, testosterone levels significantly increased as in all male (a) and all female (b) genotypes compared to weeks 1 to 11. Estradiol levels also increased significantly during puberty in females but not in males (c, d). For a–d: Standard Least Squares (LS) and incorporated Restricted Maximum Likelihood estimation followed by LS Means Tukey HSD post hoc tests for pairwise comparisons; see Supplementary Table S4. Similar letters in a-d indicate that these groups were statistically similar and different from all other groups (see text and Supplementary Table S4 for all statistical results). In e, the graph shows the testicle-weight to body-weight ratio at 20 weeks of AR^−/− males (dark blue, n = 3) to be significantly lower compared to AR^+/+ males (light blue, n = 3) (one-tailed t-test, t(4) = 14.9, p = 0.00006). f While AR^+/+ (dark red) and AR^+/− (red) females laid approximately 5 eggs per week (n = 4 females per group), no eggs were laid by AR^−/− hens (light red) (one-way ANOVA followed by Tukey-HSD: (F(2) = 193.34, p < 0.00001; Supplementary Table S5b or Source Data file). Similar letters in f indicate that these groups were statistically similar. Panel g shows at 20 weeks the bursa of Fabricius-weight to body-weight ratio of males (blue bars) and females (red bars) of AR^−/− and AR^+/+ individuals^. The bursa weight was higher in AR^−/− compared to AR^+/+ in both sexes (n = 3 per group; one-tailed t-tests, females: t(4) = 6.063, p = 0.002; males: t(4) = 6.537, p = 0.001; Supplementary Table S5a or Source Data file). For e, g*: p < 0.05 (see above). For a–d and f: Shown are box plots with the median (line inside the box), first and third quartiles and outliers. Whiskers are the smallest and largest values within 1.5 times the interquartile range. In e and g, the box and inner line represent the three data points.