Vitamin B2, also called riboflavin, is one of the B vitamins and is slightly soluble in water. The main physiological function of vitamin B2 is to promote metabolism as a coenzyme, which is an essential factor for the growth of many animals and microorganisms.

Among livestock and poultry, pigs and chickens are most likely to show vitamin B2 deficiency.
When vitamin B2 is deficient, chicks show curled toes, weak legs, and slow growth, while adult hens have decreased egg production, egg hatching rate and chick survival rate.
When pigs lack vitamin B2, they show loss of appetite, diarrhea, growth stagnation, rough fur, cloudy eye lens, stiff leg muscles, premature birth of sows, embryonic death and fetal malformation.
Young calves and lambs need to be supplied with vitamin B2 by food in the early stage of birth, and when they are deficient, they suffer from ulceration of the corners of the mouth, loss of appetite, hair loss and diarrhea.