What are the genotypes of the parents and offspring, if only black offspring are obtained

What are the genotypes of the parents and offspring, if only black offspring are obtained from the crossing of a cow with a red coat with a black bull? Identify the dominant and recessive gene.

Since all offspring demonstrate a phenotype characteristic of one of the parental individuals and the phenomenon of splitting according to the considered trait in the offspring is not observed, it should be concluded that the gene for black wool dominates over the gene for red wool in cows, and the black bull is homozygous for the gene for the dominant trait.

Let us designate the gene for the black color of the cows’ fur as K, and the gene for the red color of the wool of these animals as k.

A ginger cow must be homozygous for the ginger hair gene in order for this trait to be realized in her phenotype. She has the kk genotype and produces the same type k eggs.

The black bull has the KK genotype and produces the same type of sperm K.

All offspring from crossing a black bull with a red cow have a heterozygous Kk genotype and have black hair.

Answer: the gene for black wool is dominant, the gene for red wool is recessive. The bull is homozygous for the dominant gene (KK), the cow is homozygous for the recessive gene (kk), and the calves are heterozygous (Kk).