Figure 1. Phenotypic characteristics of hairy syndrome cattle.

(a) Photograph showing coat differences between wild-type and mutant half-sibs, with muddy coat due to wallowing behaviour typical of affected animals. (b) Hair morphology differences between mutant (N=12) and wild-type (N=12) half-sibs. (c,d) Heat stress response phenotypes of mutant (N=12) and wild-type (N=12) half-sibs measured at different ambient temperatures. Responses of twelve wild-type, seven mutant and five clipped mutants also indicated. (e) Sweating rate contrast between mutant (N=6) and wild-type (N=6) cows. (f) Differences in milk volumes between wild-type (N=740) and mutant (N=77) half-sibs. These differences underestimate the extent of lactation effects since at least 25% of mutant animals failed to initiate lactation. Box plots define the median, upper and lower quartiles for the various phenotypes, with whiskers representing the furthest data points within 1.5 × of the interquartile range, and outlier samples indicated beyond this range. *P<0.05, **P<0.001, ***P<0.0001 (two-sided t-tests, Bonferroni-adjusted).