G. N. Machakhtyrov1, V. A. Machakhtyrova2
1M. G. Safronov Yakutsk Research Institute of Agriculture, ul. Bestuzheva-Marlinskogo, 23/1, Yakutsk, 677001, Russian Federation
2Yakutsk State Agricultural Academy, ul. Krasil’nikova, 15, Yakutsk, 677007, Russian Federation
Abstract. The study of cows’ reproductive systems using an ultrasound apparatus aimed to detect heat signs during hidden estrus according to the functional state of the ovaries for timely insemination. The work was performed in the Republic of Sakha (Yakutia) in 2018. For the region, the duration of the winter tie-up keeping season is 8 months. A total of 123 nonpregnant cows of Simmental breed were examined at different stages of the reproductive cycle. Among the tested animals, in 12 cows (10%), the ovaries were in the follicular phase, including 4 cows (33.3%), for which hidden estrus was indicated. All 12 animals were inseminated with frozen and thawed sperm; 8 cows (66.7%) were diagnosed with pregnancy including external estrus manifestations in 6 cows (75%) and hidden estrus in 2 cows (50%). On average, the preovulatory follicle was 1.65 cm ± 0.03 cm large, which determined the peak of the follicular stage and served as the main criterion for determining the optimal time for artificial insemination during hidden estrus. In addition, the size of the corpus luteum served as a distinctive criterion, which averaged 1.66 cm ± 0.07 cm during regression varying from 1.2 cm to 2.7 cm. Detection of the anechogenic zone in the lumen of the uterine endometrium indicated the maturity of the preovulatory follicle. In the luteal phase, corpora lutea of the cavity type had clear boundaries and a structure with an anechogenic cavity. Corpora lutea of a solid type were characterized by granular echogenicity. At the same time, the size of corpora lutea of a solid type was significantly larger than that of corpora lutea of the cavity type by 20% (p was less or equal 0.001).
Keywords: ultrasound diagnostics; echography; corpus luteum; follicles; hidden estrus.
Author Details: G. N. Machakhtyrov, Cand. Sc. (Biol.), deputy director (e-mail: Этот адрес электронной почты защищён от спам-ботов. У вас должен быть включен JavaScript для просмотра.); V. A. Machakhtyrova, Cand. Sc. (Biol.), assoc. prof. (e-mail: Этот адрес электронной почты защищён от спам-ботов. У вас должен быть включен JavaScript для просмотра.).
For citation: Machakhtyrov GN, Machakhtyrova V A. [Examination of the functional state of cows’ ovaries by ultrasound scanning]. Dostizheniya nauki i tekhniki APK. 2020;34(1): 48-51. Russian. doi: 10.24411/0235-2451-2020-10109.