Reducción del “período abierto” en vacas lecheras cruzadas mediante la optimización del protocolo Ovsynch: Un análisis comparativo de la inseminación a las 48 y 56 horas

Jorge Maure; Alberto Gamarra; Edwin Pile

doi:10.48204/semillaeste.v6n1.7881

Submitted August 3, 2025

Published 2025-10-21

Artículos

Vol. 6 No. 1 (2025): Revista Semilla del Este

Reducing the open period in crossbred dairy cows by optimizing the Ovsynch protocol: A comparative analysis of insemination at 48 and 56 hours.

Jorge Maure⁺⁻
Alberto Gamarra⁺⁻
Edwin Pile⁺⁻

DOI https://doi.org/10.48204/semillaeste.v6n1.7881

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References

DOI: 10.48204/semillaeste.v6n1.7881

Published: 2025-10-21

How to Cite

Maure, J., Gamarra, A., & Pile, E. (2025). Reducing the open period in crossbred dairy cows by optimizing the Ovsynch protocol: A comparative analysis of insemination at 48 and 56 hours. Revista Semilla Del Este, 6(1), 91–101. https://doi.org/10.48204/semillaeste.v6n1.7881

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

Abstract

The optimization of Fixed-Time Artificial Insemination (FTAI) protocols is key for profitability in tropical livestock farming. This study compared the effect of two FTAI timings (48 vs. 56 hours post-PGF2a) within an Ovsynch protocol on reproductive parameters in crossbred dairy cows (Bos taurus x Bos indicus). Forty-six lactating cows were randomly assigned to one of two groups: Ovsynch-48 (n=24) and Ovsynch-56 (n=22). The pregnancy rate was not significantly different between the 48-hour group (37.5%) and the 56-hour group (18.2%) (x²=1.267, p=0.260). However, the Ovsynch-56 protocol significantly reduced the total days open compared to the Ovsynch-48 protocol (p=0.039). Additionally, no significant effect of the number of parities or body condition on the probability of pregnancy was found. It is concluded that, while both protocols yield statistically similar pregnancy rates, the 56-hour protocol offers a strategic advantage by shortening the days open, thereby improving a key indicator of reproductive efficiency.

References

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