Pre-Parturient Mare Behavior. Mares will generally foal after an 11-month gestation, but this is highly variable. Studies have shown a range of gestation from 315 to 387 days, with an average of about 341 days.
Punnett squares are most commonly used to examine genotype probabilities from one genetic locus at a time. They can be used to look at more than one locus at time, but some find the resulting diagrams complicated and difficult to interpret.
A Punnett Square for a tetrahybrid cross contains 256 boxes with 16 phenotypes and 81 genotypes. A third allele for any one of the traits increases the number of genotypes from 81 to 108. Given this complexity, Punnett Squares are not the best method for calculating genotype and phenotype ratios for crosses involving more than one trait. Test your understanding with the Punnett Square Calculator Problem Set. Video Overview