A follicle and a luteinized cystic follicle
Keywords: CL,corpus, luteum, cystic, bovine, cycle, infertility, cow, ultrasound
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A follicle together and a luteinized cystic follicle seen by transrectal ultrasonography in a cow.
Together with its appearance, a history of postpartum anestrous allowed a diagnosis of a luteinized cystic follicle (sometimes referred to a luteal cyst) in this cow. Cystic follicles and the luteinized structures they develop into, are abnormal structures, associated with an absence of estrous cycles in the early to late postpartum period; almost always in dairy cows. In dairy cows, abnormal estrogen secretion and abnormal LH surges are thought to be important in the syndrome. Cystic follicles are also seen in beef heifers, but usually only after the use of steroid growth promoters.
Clarification: Cystic corpora lutea are normal structures, associated with normal estrous cycles. Most corpora lutea luteinize completely, obliterating the antrum of the ovulated follicle but many are left with small to large cysts in the center. This author does not use the term “luteal cyst” (an abnormal structure) because it can easily be confused with the term “cystic corpus luteum” (a normal structure). Instead, the term luteinized cyst (a cystic follicle that has become luteinized) should be used.
