Estrus Detection and Optimal Insemination Timing in Holstein Cattle Using a Neck-Mounted Accelerometer Sensor System
Authors:
- Jacobo ÁlvarezJÁJacobo Álvarez
- Antía AcciónAAAntía Acción
- Elio LópezELElio López
- Carlota AnteloCACarlota Antelo
- Renato BarrionuevoRBRenato Barrionuevo
- Juan José BecerraJuan José Becerra
- Ana Isabel PeñaAPAna Isabel Peña
- Pedro García HerradónPHPedro García Herradón
- Luis Ángel QuintelaLuis Ángel Quintela
- Uxía YáñezUYUxía Yáñez
Open Access
Abstract
This study aimed to evaluate the accuracy of the accelerometer-equipped collar RUMI to detect estrus in dairy cows, establish a recommendation for the optimal timing for artificial insemination (AI) when using this device, and characterize the blood flow of the dominant follicle (F) and the corpus luteum (CL) as ovulation approaches. Forty-seven cycling cows were monitored following synchronization with a modified G6G protocol, allowing for spontaneous ovulation. Ultrasound examinations were conducted every 12 h, starting 48 h after the second PGF2α dose, to monitor uterine and ovarian changes. Blood samples were also collected to determine serum progesterone (P4) levels. Each cow was fitted with a RUMI collar, which continuously monitored behavioral changes to identify the onset, offset, and peak of activity of estrus. One-way ANOVA assessed the relationship between physiological parameters and time before ovulation. Results showed that the RUMI collar demonstrated high specificity (100%), sensitivity (90.90%), and accuracy (93.62%) for estrus detection. The optimal AI window was identified as between 11.4 and 15.5 h after heat onset. Increased blood flow to the F and reduced luteal activity were observed in the 48 h prior to ovulation. Further research is needed to assess the influence of this AI window on conception rates, and if it should be modified considering external factors.Keywords
Funding Information
- Fundación Caixa Rural Tomás Notario Vacas (2024 call) (ED481_033/2024)
- Xunta de Galicia (ED481_033/2024)
This publication has 45 references indexed in Scilit:
- Relationships between activity monitoring device data and ovarian, uterine, hormonal, and pregnancy variables in beef cowsTheriogenology, 2025
- Application note: Validation of BovHEAT — An open-source analysis tool to process data from automated activity monitoring systems in dairy cattle for estrus detectionComputers and Electronics in Agriculture, 2021
- Evaluation of an ear-attached accelerometer for detecting estrus events in indoor housed dairy cowsTheriogenology, 2019
- Development of fertility programs to achieve high 21-day pregnancy rates in high-producing dairy cowsTheriogenology, 2018
- Automated activity monitoring and visual observation of estrus in a herd of loose housed Hereford cattle: Diagnostic accuracy and time to ovulationTheriogenology, 2017
- Effects of insemination–ovulation interval on fertilization rates and embryo characteristics in dairy cattleTheriogenology, 2006
- Blood flow: A key regulatory component of corpus luteum function in the cowDomestic Animal Endocrinology, 2005
- Influence of repeated rectal ultrasound examinations on hormone profiles and behaviour around oestrus and ovulation in dairy cattleTheriogenology, 2004
- Relationship between level of milk production and estrous behavior of lactating dairy cowsAnimal Reproduction Science, 2004
- Synchronization of ovulation in dairy cows using PGF2α and GnRHTheriogenology, 1995