Causes of variation in the frequency of monozygous and dizygous twinning in various breeds of cattle.
D000022:Abortion, Spontaneous; D000818:Animals; D002417:Cattle; D005260:Female; D009026:Mortality; D010298:Parity; D010641:Phenotype; D011247:Pregnancy; D012621:Seasons; D012744:Sex Ratio; D013045:Species Specificity; D013997:Time Factors; D014310:Triplets; D014427:Twins