A follicle and a luteinized cystic follicle

Keywords: CL,corpus, luteum, cystic, bovine, cycle, infertility, cow, ultrasound

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A follicle 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.

Leucosis in the uterus of a cow

Keywords: bovine, COD, cystic, BLV, leucosis, uterus, bovine

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Bovine leucosis is caused by the bovine leukemia virus (BLV). Many cows are carriers and asymptomatic. In this case, as shown by the arrows, there are multiple foci of leucosis in the uterus of the cow. This cow also had a cystic CL,in the right ovary; a normal structure in many cycling cows (not to be confused with a luteinized cyst).

Luteinized follicles. COD in a cow.

Keywords: COD, cystic, ovarian, ovary, luteinization, disease, cow, production, bovine

Several follicles in one ovary show various degrees of luteinization after chronic low-grade LH stimulation. The presence of numerous follicles indicate that there was no deficiency of FSH in this cow. As is usually the case for cows with cystic ovarian disease (COD) this cow would probably not have shown estrus for a prolonged period of time.

It was once believed that these cows would not ovulate while cystic structures such as these persisted in their ovaries. However it has since been shown that estrous cycles may resume with ovulations adjacent to these cystic structures.

COD in dairy cows is usually associated with high levels of milk production; in beef cows is associated with the use of steroid containing growth promoters.