Czech J. Anim. Sci., 2023, 68(6):231-244 | DOI: 10.17221/208/2022-CJAS

Timed artificial insemination protocols in dairy cattle: Functioning, shortcomings, and improvementsReview

Amine Boudaoud
LESPA, Department of Veterinary sciences, Institute of Veterinary and Agronomic Sciences, University of Batna 1, Batna, Algeria

Oestrus detection is currently at the top of the factors limiting the success of artificial insemination in dairy herds. This limitation becomes more pronounced as milk production increases because of higher metabolic clearance rates of steroid hormones leading to low circulating oestradiol concentration near oestrus. The standard OvSynch has overcome this problem by enabling fixed-time artificial insemination, for it synchronises follicular wave emergence, luteolysis, and ovulation. However, it did not improve fertility compared to cycles with spontaneous ovulation, which motivated the development of “fertility programs”. These later are nothing but improved OvSynch protocol. This article explains what went wrong with the original OvSynch protocol, discusses the improvements made by “fertility programs”, and highlights the advantages and limits of the newly tested molecules.

Keywords: OvSynch protocol; fertility program; dairy herd; synchronised ovulation

Received: November 26, 2022; Accepted: April 28, 2023; Prepublished online: June 14, 2023; Published: June 16, 2023  Show citation

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Boudaoud A. Timed artificial insemination protocols in dairy cattle: Functioning, shortcomings, and improvements. Czech J. Anim. Sci. 2023;68(6):231-244. doi: 10.17221/208/2022-CJAS.
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