Conventional fixed-time artificial insemination (FTAI) compared to block FTAI in Nelore cows


  • Daniele Alves Corrêa de Abreu Instituto Federal Goiano - Campus Urutaí
  • Wesley José de Souza Instituto Federal Goiano - Campus Urutaí
  • Geisiana Barbosa Gonçalves Instituto Federal Goiano - Campus Urutaí
  • Natália de Fátima Borges Martins Instituto Federal Goiano - Campus Urutaí
  • Wolff Camargo Marques Filho Instituto Federal Goiano - Campus Urutaí
  • Andressa Silva Nascimento Instituto Federal Goiano - Campus Urutaí



Follicle, Bovine reproduction, Pregnancy rate


Conventional Fixed-Time Artificial Insemination (FTAI) is a biotechnology widely used in beef cattle, however, the technique has shown fertility rates of females almost stabilized. Block FTAI is a technique that aims to maximize these rates, since to obtain good pregnancy results, insemination needs to be performed close to ovulation, this period is defined by the interaction between the inducer and the diameter of the dominant follicle. In this work, the objective was to analyze the pregnancy rate of Nelore cows, comparing the Block FTAI with the conventional FTAI, in two different protocols that are more used in the region, diverging only by the ovulation inducer, being Estradiol Cypionate and o Estradiol benzoate, and amount of handling. Forty multiparous Nellore cows were used. With 10 females in each of the four groups: conventional FTAI with cypionate, FTAI in Block with cypionate, conventional FTAI with benzoate and FTAI in Block with benzoate. FTAI in blocks with cypionate showed a higher pregnancy rate of 70% (P = 0.079), thus, it is a good alternative for producers in the region who did not know this technique. 


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How to Cite

Abreu, D. A. C. de, Souza, W. J. de, Gonçalves, G. B., Martins, N. de F. B., Marques Filho, W. C., & Nascimento, A. S. (2023). Conventional fixed-time artificial insemination (FTAI) compared to block FTAI in Nelore cows. Multi-Science Journal, 6(1), 15–19.



Agricultural Sciences

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