Abstract #842
Section: Production, Management and the Environment
Session: Production, Management, and the Environment VI
Format: Oral
Day/Time: Thursday 9:15 AM–9:30 AM
Location: Panzacola F-4
Session: Production, Management, and the Environment VI
Format: Oral
Day/Time: Thursday 9:15 AM–9:30 AM
Location: Panzacola F-4
# 842
Effects of expression of estrus measured by activity monitors on ovarian dynamics and conception risk in Holstein cows.
Augusto M. L. Madureira*1,2, Bruna F. Silper2, Tracy A. Burnett2, Liam B. Polsky2, Eraldo L. Drago Filho1, Sergio Soriano3, Alex F. Sica3, José L. M. Vasconcelos1, Ronaldo L. A. Cerri2, 1Sao Paulo State University, Botucatu, SP, Brazil, 2University of British Columbia, Vancouver, BC, Canada, 3Colorado Dairies, Araras, SP, Brazil.
Key Words: pedometer, follicle, pregnancy
Effects of expression of estrus measured by activity monitors on ovarian dynamics and conception risk in Holstein cows.
Augusto M. L. Madureira*1,2, Bruna F. Silper2, Tracy A. Burnett2, Liam B. Polsky2, Eraldo L. Drago Filho1, Sergio Soriano3, Alex F. Sica3, José L. M. Vasconcelos1, Ronaldo L. A. Cerri2, 1Sao Paulo State University, Botucatu, SP, Brazil, 2University of British Columbia, Vancouver, BC, Canada, 3Colorado Dairies, Araras, SP, Brazil.
The objective of this study was to determine intensity of physical activity as a result of estrus expression and its relationship with ovarian dynamics and fertility. Estrus events were recorded at 2 commercial dairies. A collar-mounted accelerometer (Collar; SCR Heatime) and a leg-mounted pedometer (Leg1; Boumatic Heat-seeker-TX) were used in farm 1. A second leg-mounted pedometer (Leg2; AfiMilk Pedometer Plus) was used in farm 2. Only spontaneous estrus (SE) events were registered at farm 1 (collar and Leg1; 1,099 events; 318 cows). Cows with Leg2-tags were induced to ovulate (IO; 1,411 events; 1,040 cows) with an E2/P4-based TAI protocol. Blood samples and ovarian ultrasonography were done at detection of activity increase (SE), or at the moment of AI and 10 d after AI (IO). IO cows’ were scanned on d 7 after AI to assess CL presence. Pregnancy diagnosis was performed at 42 ± 7 d. Data were analyzed with ANOVA, logistic regression, proc MIXED. Peak estrus activity (PA) for Collar was 71.6 ± 20.7 index value, and for Leg1 and Leg2, 334.3 ± 155.7% and 286.18 ± 163.3% relative increase. Pre-ovulatory follicle diameter was 18.8 ± 0.3 mm (SE) and 13.3 ± 3.5mm (IO). Follicle diameter was not correlated with AAM measurements (r = 0.007). Cows with high PA had greater E2 concentration (9.5 ± 0.3 vs. 8.2 ± 0.2 ng/mL [Collar]; 8.9 ± 0.2 vs. 8.1 ± 0.2ng/mL [Leg1]). P4 concentration at d of AI was not correlated with relative increase (Leg2), but it was higher on d 10 for cows that had more intense estrus (3.17 ± 0.11 ng/mL vs. 3.73 ± 0.21 ng/mL). Cows with greater PA had greater P/AI than those with lower PA (36.5% vs. 24.6% [Collar], 33.5% vs. 21.4% [Leg1] and 42.9% vs. 28.9% [Leg2]). Likelihood of ovulation was greater for high vs. low relative increase (94.6% vs. 86.2%). Greater estrus intensity improved ovulation and P/AI. Data from AAM might be used to survey and predict fertility measures in dairy cows. More studies are needed to determine management and selection tools to improve estrus expression, detection, and fertility.
Key Words: pedometer, follicle, pregnancy
