Estrus Detection and Optimal Insemination Timing in Holstein Cattle Using a Neck-Mounted Accelerometer Sensor System
Abstract
Highlights
- The neck-mounted accelerometer-based sensor RUMI demonstrated high specificity, sensitivity, and accuracy for estrus detection in high-producing Holstein cows.
- The optimal timing for artificial insemination was identified as 11–15 h after estrous onset.
- Improved heat detection accuracy can enhance reproductive performance and reduce economic losses associated with missed estrus events and failed inseminations.
- The integration of sensor-based estrus detection reduces reliance on hormones, addressing societal concerns regarding animal welfare and food safety.
Abstract
1. Introduction
2. Materials and Methods
2.1. Animals
2.2. Automated Estrus-Detection Systems
2.3. Synchronization of Estrus
2.4. Ultrasound and Sampling
2.5. Statistical Analyses
3. Results
4. Discussion
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Protocol | Response | Heat Duration (h) | Maximum Heat (h) | Interval Heat Onset–Ovulation (h) | Interval Heat Offset–Ovulation (h) | Interval Last PGF2α–Ovulation (h) | Time Before Ovulation When Progesterone < 1 ng/mL (h) | Interval 2nd PGF2α–Ovulation (h) |
---|---|---|---|---|---|---|---|---|
G6G1PG | 73.33% (22/30) | 12.40 ± 4.51 | 6.80 ± 4.54 | 28.45 ± 6.05 | 15.80 ± 7.76 | 100 ± 15.57 | 41.00 ± 15.57 | 100.00 ± 15.57 |
G6G2PG | 64.70% (11/17) | 10.90 ± 4.01 | 5.20 ± 2.74 | 25.50 ± 3.34 | 14.30 ± 5.36 | 72.40 ± 13.91 | 35.67 ± 10.58 | 96.4 ± 13.91 |
RUMI Alert | Ultrasonography | |
---|---|---|
Heat | No Heat | |
Heat | 90.9% (30/33) | 0% (0/14) |
No heat | 9.1% (3/33) | 100% (14/14) |
Mean ± SD | Minimum | Maximum | Median | |
---|---|---|---|---|
Heat duration (h) | 11.90 ± 4.34 | 6 | 21 | 11.50 |
Maximum heat (h) | 6.27 ± 4.05 | 1 | 20 | 6 |
Interval heat onset–ovulation (h) | 27.47 ± 5.42 | 10 | 39 | 27 |
Interval heat offset–ovulation (h) | 15.30 ± 6.99 | 14 | 27 | 17 |
Interval 2nd PGF2α–ovulation (h) | 90.80 ± 19.85 | 52 | 136 | 88 |
Time before ovulation when progesterone < 1 ng/mL (h) | 39.34 ± 14.24 | 17 | 77 | 41 |
Hours Before Ovulation | −48 (n = 11) | −36 (n = 17) | −24 (n = 26) | −12 (n = 30) | −6 (n = 30) |
---|---|---|---|---|---|
P4 (ng/mL) | 0.81 ± 1.07 a | 0.42 ± 0.44 ab | 0.32 ± 0.20 b | 0.39 ± 0.37 ab | 0.27 ± 0.32 b |
MFA (mm) | 16.80 ± 2.57 a | 19.41 ± 4.16 ab | 20.33 ± 4.52 ab | 21.14 ± 3.90 b | 20.89 ± 4.57 b |
mFA (mm) | 13.89 ± 2.42 a | 15.74 ± 3.40 ab | 17.11 ± 4.02 ab | 16.56 ± 2.79 ab | 17.21 ± 3.02 b |
MFB (mm) | 14.62 ± 7.10 a | 17.60 ± 4.03 a | 17.86 ± 4.10 a | 18.28 ± 4.12 a | 17.33 ± 5.14 a |
mFB (mm) | 12.67 ± 5.81 a | 14.21 ± 4.11 a | 14.32 ± 3.21 a | 14.68 ± 4.64 a | 13.86 ± 3.16 a |
MCL (mm) | 18.41 ± 3.20 a | 17.84 ± 4.69 a | 17.03 ± 2.86 a | 17.60 ± 3.61 a | 17.53 ± 1.80 a |
mCL (mm) | 14.14 ± 3.20 a | 13.97 ± 3.35 a | 14.00 ± 1.69 a | 13.93 ± 3.15 a | 13.70 ± 2.83 a |
END (mm) | 10.49 ± 2.17 a | 9.70 ± 2.41 a | 10.18 ± 3.33 a | 9.81 ± 2.86 a | 9.93 ± 2.64 a |
MIO (mm) | 4.39 ± 1.10 a | 4.73 ± 1.81 a | 3.83 ± 0.89 a | 4.42 ± 1.39 a | 4.76 ± 2.30 a |
END/MIO | 2.52 ± 0.75 a | 2.39 ± 1.46 a | 2.79 ± 1.16 a | 2.40 ± 0.89 a | 2.36 ± 0.90 a |
UL (mm) | 6.21 ± 4.73 a | 6.26 ± 2.95 a | 5.05 ± 4.19 a | 5.04 ± 3.85 a | 3.44 ± 3.80 a |
Hours Before Ovulation | −48 | −36 | −24 | −12 | −6 |
---|---|---|---|---|---|
FA * | N = 10 | N = 16 | N = 22 | N = 27 | N = 29 |
0 | 100% (10/10) | 81.3% (13/16) | 86.4% (9/22) | 70.4% (19/27) | 51.7% (15/29) |
1 | 0% (0/10) | 18.75% (3/16) | 9.1% (2/22) | 3.7% (1/27) | 20.6% (6/29) |
2 | 0% (0/10) | 0% (0/16) | 0% (0/22) | 25.9% (7/27) | 13.8% (4/29) |
3 | 0% (0/10) | 0% (0/16) | 4.5% (1/22) | 0% (0/27) | 13.8% (4/29) |
FB * | N = 5 | N = 11 | N = 14 | N = 14 | N = 14 |
0 | 100% (5/5) | 90.9% (10/11) | 92.9% (13/14) | 78.6% (11/14) | 85.7% (12/14) |
1 | 0% (0/5) | 9.1% (1/11) | 0% (0/14) | 7.1% (1/14) | 0% (0/14) |
2 | 0% (0/5) | 0% (0/11) | 0% (0/14) | 14.3% (2/14) | 7.15% (1/14) |
3 | 0% (0/5) | 0% (0/11) | 7.1% (1/14) | 0% (0/14) | 7.15% (1/14) |
CL ** | N = 8 | N = 12 | N = 10 | N = 10 | N = 7 |
0 | 12.5% (1/8) | 66.67% (8/12) | 70% (7/10) | 80% (8/10) | 100% (7/7) |
1 | 50% (4/8) | 16.67% (2/12) | 20% (2/10) | 20% (2/10) | 0% (0/10) |
2 | 37.5% (3/8) | 16.67% (2/12) | 10% (1/10) | 0% (0/10) | 0% (0/10) |
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Álvarez, J.; Acción, A.; López, E.; Antelo, C.; Barrionuevo, R.; Becerra, J.J.; Peña, A.I.; Herradón, P.G.; Quintela, L.Á.; Yáñez, U. Estrus Detection and Optimal Insemination Timing in Holstein Cattle Using a Neck-Mounted Accelerometer Sensor System. Sensors 2025, 25, 5245. https://doi.org/10.3390/s25175245
Álvarez J, Acción A, López E, Antelo C, Barrionuevo R, Becerra JJ, Peña AI, Herradón PG, Quintela LÁ, Yáñez U. Estrus Detection and Optimal Insemination Timing in Holstein Cattle Using a Neck-Mounted Accelerometer Sensor System. Sensors. 2025; 25(17):5245. https://doi.org/10.3390/s25175245
Chicago/Turabian StyleÁlvarez, Jacobo, Antía Acción, Elio López, Carlota Antelo, Renato Barrionuevo, Juan José Becerra, Ana Isabel Peña, Pedro García Herradón, Luis Ángel Quintela, and Uxía Yáñez. 2025. "Estrus Detection and Optimal Insemination Timing in Holstein Cattle Using a Neck-Mounted Accelerometer Sensor System" Sensors 25, no. 17: 5245. https://doi.org/10.3390/s25175245
APA StyleÁlvarez, J., Acción, A., López, E., Antelo, C., Barrionuevo, R., Becerra, J. J., Peña, A. I., Herradón, P. G., Quintela, L. Á., & Yáñez, U. (2025). Estrus Detection and Optimal Insemination Timing in Holstein Cattle Using a Neck-Mounted Accelerometer Sensor System. Sensors, 25(17), 5245. https://doi.org/10.3390/s25175245