Progress 10/01/07 to 09/30/11
Outputs
OUTPUTS: The Specific Aim of this proposal is to develop management strategies to improve reproduction in lactating dairy cows, thereby improving profitability and competitiveness of dairy operations. Results from the experiments in this project were presented to dairy scientists at the 2011 American Association of Dairy Science meetings in New Orleans, LA and to dairy producers, county Extension agents, and veterinarians through national, statewide, and local extension meetings. PARTICIPANTS: Individuals who worked on this project include my colleagues, Dr. Milo Wiltbank and Dr. Victor Cabrera in the Dairy Science Department at the University of Wisconsin - Madison. My graduate students working on this project include my Ph.D. student, Julio Giordano, my M.S. student, Glaucio Lopes, and a visiting Ph.D. student from Italy, Alessio Valenza. My technician, Mr. Jerry Guenther, also was involved with these projects. TARGET AUDIENCES: Target audiences for this work include dairy scientists, reproductive physiologists, dairy producers, county Extension agents, and veterinarians. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Several economic evaluation tools have been developed and made available on the web to help dairy producers and veterinarians to calculate the economic impact of the reproductive protocols developed through this research. These economic evaluation tools can help dairy farmers to motivate change in their management strategies to improve reproduction on their farms.
Publications
- Giordano, J. O., J. N. Guenther, G. Lopes Jr., and P. M. Fricke. 2012. Changes in serum pregnancy-associated glycoprotein (PAG) pregnancy specific protein B (PSPB), and progesterone concentrations before and after induction of pregnancy loss in lactating dairy cows. J. Dairy Sci. (in press).
- Giordano, J. O., M. C. Wiltbank, J. N. Guenther, R. Pawlisch, S. Bas, A. P. Cunha, and P. M. Fricke. 2012. Increased fertility in lactating dairy cows resynchronized with Double-Ovsynch when compared to Ovsynch initiated 32 d after Timed AI. J. Dairy Sci. (in press).
- Giordano, J. O., P. M. Fricke, M. C. Wiltbank, and V. E. Cabrera. 2012. Economic decision making support system for selection of reproductive management programs on dairy farms. J. Dairy Sci. (in press).
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Progress 01/01/10 to 12/31/10
Outputs
OUTPUTS: Effect of presynchronization with GnRH or hCG 7 d before resynchronization of ovulation initiated 25 d after a previous timed AI on fertility of lactating dairy cows. J. O. Giordano, J. N. Guenther, G. Lopes Jr., M. M. Herlihy, A. B. Nascimento, M. C. Wiltbank, and P. M. Fricke, Department of Dairy Science, University of Wisconsin, Madison To determine the effect of presynchronization on fertility to resynchronization of ovulation (Resynch), lactating cows on a commercial dairy initiated Resynch 25 d after a prior TAI using GnRH and cloprostenol (PGF) as follows: (d 0, 200 ug GnRH; d 7, 750 ug PGF; 56 h, 100 ug GnRH; 16 h, TAI). At the prior TAI, cows were randomly assigned to one of three treatments to receive: 2,000 IU hCG (Chorulon) 7 d before initiation of Resynch (HGPG, n=346); 200 ug GnRH 7 d before initiation of Resynch (GGPG, n=361); or no presynchronization (C, n=375). Cows diagnosed not pregnant at the PGF injection of Resynch (32 d after prior TAI) continued the protocols, and pregnancy was diagnosed at 32 and 53 d after Resynch TAI to determine pregnancies per AI (P/AI). Based on logistical regression analysis, treatment tended (P=0.07) to affect P/AI 32 d after TAI [HGPG = 33.0% (114/346); GGPG = 30.8% (111/361); C = 25.3% (95/375)]. Based on statistical contrasts, HGPG cows had more (P=0.02) P/AI than C cows, whereas P/AI for GGPG vs. C cows tended (P=0.10) to differ and HGPG vs. GGPG cows did not (P=0.53) differ. Pregnancy loss from 32 to 53 d after Resynch TAI was not affected by parity and did not differ (P=0.29) among treatments [HGPG = 6.3% (7/112); GGPG = 9.9% (11/111); C = 4.3% (4/93)]. Treatment did not affect (P=0.13) P/AI at 53 d after TAI when all treatments were included in the model; however, when analyzed separately, HGPG cows tended to have more (P=0.08) P/AI 53 d after Resynch TAI than C cows [30.5% (105/344) vs. 23.9% (89/373)]. Based on a subset of cows, ovulation to the last GnRH injection of Resynch did not differ among treatments [HGPG = 89.3% (176/197); GGPG = 89.8% (168/187); C = 89.9% (177/197)]. We conclude that presynchronization with hCG or GnRH 7 d before initiation of Resynch did not affect synchronization rate, but that hCG increased fertility whereas GnRH tended to increase fertility compared to Ovsynch initiated 25 d after a prior TAI. PARTICIPANTS: These experiments were done in collaboaration with my colleague, Dr. Milo C. Wiltbank, in the Department of Dairy Science at the University of Wisconsin - Madison. In addition, Mr. Julio O. Giordano, is my graduate student, and these experiments will be a part of his Ph.D. dissertation. TARGET AUDIENCES: Target audiences include: veterinarians, county extension agents, dairy farmers, and the AI industry. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Presynchronization with hCG or GnRH 7 d before initiation of Resynch did not affect synchronization rate, but that hCG increased fertility whereas GnRH tended to increase fertility compared to Ovsynch initiated 25 d after a prior TAI.
Publications
- Giordano, J. O., J. N. Guenther, M. S. Ares, M. C. Wiltbank, and P. M. Fricke. 2010. Presynchronization with hCG 7 d before initiation of Resynch improves fertility similar to a Double-Ovsynch Resynch protocol in lactating dairy cows. J. Dairy Sci. 93(E-Suppl. 1):219.
- Giordano, J. O., J. N. Guenther, G. Lopes Jr., M. M. Herlihy, A. B. Nascimento, M. C. Wiltbank, and P. M. Fricke. 2010. Effect of presynchronization with GnRH or hCG 7 d before resynchronization of ovulation initiated 25 d after a previous timed AI on fertility of lactating dairy cows. J. Dairy Sci. 93(E-Suppl. 1):676.
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Progress 01/01/09 to 12/31/09
Outputs
OUTPUTS: A multisite collaborative research study was conducted. Our objective was to determine the effect of exogenous progesterone (P4) during timed artificial insemination (TAI) protocol on pregnancies per AI (P/AI) in dairy cows not previously observed in estrus. Lactating cows (3,338) from 7 commercial dairy herds were submitted to a presynchronization protocol (2 injections of PGF2 alpha 14 d apart; Presynch), and cows in estrus after the second PGF2 alpha received AI (EDAI; 1,652). Cows not inseminated by 12 to 14 d after the second PGF2 alpha injection were submitted to a TAI protocol (GnRH on d 0, PGF2 alpha on d 7, GnRH 48 to 72 h after PGF2 alpha, and TAI 0 to 24 h after GnRH). At onset of the TAI protocol, cows were balanced by parity and DIM and assigned randomly to receive no exogenous P4 (control, 815) or a controlled internal drug release (CIDR) insert containing 1.38 g of P4 from d 0 to 7 (CIDR, 871). Blood samples collected at the second PGF2 alpha injection of the Presynch protocol and on the day of the first GnRH injection of the TAI protocol for P4 determination. When P4 in both samples was less than 1.0 ng/mL, cows were classified as anovular, whereas cows having at least 1 sample greater than 1.0 ng/mL were classified as cyclic. Concentration of P4 at 11 to 14 d after AI was determined in a subgroup of cows (453) from 2 sites. Pregnancy was diagnosed at 40 and 65 d after AI. PARTICIPANTS: This experiment was conducted in 7 commercial dairy herds located in Arizona (one open dry lot dairy), California (two free-stall dairies and one open dry lot dairy), Kansas (two free-stall dairies), and Wisconsin (one free-stall dairy). Collaborators included R. C. Chebel (UC Davis), M. J. Al-Hassan and P. M. Fricke (University of Wisconsin), J.E.P. Santos (University of Florida), J. S. Stevenson (Kansas State University), R. L. Ax (University of Arizona). TARGET AUDIENCES: These results were presented to scientists at the National ADSA meetings and to veterinarians, dairy producers, and county extension agents at meetings held throughout the past year. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Proportion of cows inseminated on estrus after the second PGF2 alpha injection of the Presynch protocol differed among herds (range of 26.6 to 61.1 percent). Results showed that P/AI for EDAI cows at 40 and 65 d were 35.9 and 34.9 percent, respectively, and pregnancy loss was 9.0 percent. Proportion of cyclic cows at the onset of the TAI protocol differed among herds (range from 66.5 to 86.3 percent), but did not differ between treatments (control = 72.5, CIDR = 74.0 percent). Treatment tended to and affected P/AI at 40 (control, 33.4; CIDR = 37.9 percent) and 65 (control, 30.1, CIDR, 34.9 percent) d after AI, respectively, but it did not affect pregnancy loss (8.7 percent). Cyclic cows had greater P/AI at 40 (38.3 vs. 28.9 percent) and 65 d (35.2 vs. 25.8 percent) after AI, but cyclic status had no effect on pregnancy loss. The interaction between treatment and cyclic status and between treatment and herd did not affect P/AI at 40 and 68 d after AI. Treatment affected P4 concentration after AI, with more CIDR cows having P4 greater than 1.0 ng/mL (94.4 vs. 86.9 percent) and P4 greater than 3.2 ng/mL (81.8 vs. 68.0 percent) at 11 to 14 d after AI compared with control cows. Treatment of cows not previously observed in estrus with a CIDR insert during a TAI protocol increased proportion of cows with functional CL after AI and P/AI. These results were presented to scientists at the National ADSA meetings and to veterinarians, dairy producers, and county extension agents at meetings held throughout the past year.
Publications
- Chebel, R. C., M. J. Al-Hassan, P. M. Fricke, J. R. Lima, J. E. P. Santos, C. A. Martel, J. S. Stevenson, R. Garcia, R. L. Ax, and F. Moreira. 2010. Supplementation of progesterone via CIDR inserts during ovulation synchronization protocols in lactating dairy cows. J. Dairy Sci. (In press).
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Progress 01/01/08 to 12/31/08
Outputs
OUTPUTS: Results from this work have been disseminated through the PI's statewide, national, and international Extension program in Dairy Cattle Reproduction. Methods of dissemination include oral presentation at extension and scientific meetings for dairy producers, veterinarians, and researchers as well as through the PI's web site. PARTICIPANTS: Cooperating Agencies and Personnel: Wisconsin Agricultural Experiment Station and P. M. Fricke (project leader), and Milo Wiltbank, Department of Dairy Science, University of Wisconsin-Madison. In addition, ag experiment stations from Kansas State University (J. S. Stevenson); Purdue University (R. L. Krisher); University of Minnesota (G. C. Lamb); Michigan State University (J. R. Pursley); University of Missouri (H. A. Garverick) were involved with this collaborative experiment. At each university, this experiment was a component of a graduate student's professional development. TARGET AUDIENCES: Target audiences for this information include: dairy veterinarians, dairy producers, county agricultural agents, and allied dairy industry personnel. Methods of dissemination include local and regional scientific and Extension meetings, as well as dissemination on University web sites. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Our objective was to determine the effect of exogenous progesterone (P4) during timed AI protocols on pregnancy risk (PR) in dairy cows not previously observed in estrus. Lactating cows, from 6 dairy herds, were submitted to a Presynch protocol (2 injections of PGF2 alpha [PGF] 14 d apart), and cows in estrus after the second PGF received AI (EDAI, n = 1366). Cows not inseminated by 12-14 d after the end of the Presynch received a timed AI (TAI) protocol (GnRH [d 0], PGF [d 7], GnRH [48-72 h after PGF], TAI [0-24 h after GnRH]). At onset of the TAI protocol cows were blocked by parity and DIM and randomly assigned to receive no exogenous P4 (CON, n = 721) or a CIDR insert (CIDR, n = 770). Blood was sampled at the second PGF injection of Presynch and at onset of the TAI protocol for P4 determination. Cows with 2 samples in which P4 < 1.0 ng/mL were classified as anovular and those with 1 or 2 samples in which P4 > 1.0 ng/mL were classified as cyclic. Pregnancy was diagnosed at 38 and 62 d after AI. Data were analyzed including all cows or only cows randomly allocated into treatments. Proportion of cows inseminated following the Presynch was different among sites (P < 0.01). Proportion of anovular cows at the onset of the TAI protocol was affected (P < 0.01) by site (range 13.7 to 33.5%), but it was similar (P = 0.88) between treatments (CON = 25.7, CIDR = 26.0%). When all cows were considered, treatment did not (P = 0.12) affect PR at 38 d (CON = 33.7, CIDR = 37.9, EDAI = 38.5%), but it tended (P = 0.08) to affect PR at 62 d (CON = 30.0, CIDR = 34.9, EDAI = 34.9%). When only cows randomly assigned to treatments were considered (model 2), PR at 38 and 62 d tended to be (CON = 33.7, CIDR = 37.9%; P = 0.10) and was (CON = 30.0, CIDR = 34.9%; P = 0.05) improved by exogenous P4, respectively. Cyclic cows had greater (P < 0.01) PR at 38 (38.4 vs. 29.1%) and 62 (34.9 vs. 25.7%) d than anovular cows, but PR did not differ (P > 0.15) among sites at 38 (range 31.9 to 42.4%) and 62 (range 28.6 to 37.5%) d. Use of exogenous P4 during TAI protocols improved fertility of lactating dairy cows not previously observed in estrus.
Publications
- Stevenson, J. S., D. E. Tenhouse, R. L. Krisher, G. C. Lamb, C. R. Dahlen, J. R. Pursley, N. M. Bello, P. M. Fricke, M. C. Wiltbank, D. J. Brusveen, M. Burkhart, R. S. Youngquist, and H. A. Garverick. 2008. Detection of anovulation by heatmount detectors and transrectal ultrasonography before treatment with progesterone in a timed insemination protocol. J. Dairy Sci. 91:2901-2915.
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Progress 01/01/07 to 12/31/07
Outputs
OUTPUTS: The primary objective of this project was to evaluate pregnancies per AI (P/AI) after synchronization of ovulation using one of two modifications of Ovsynch: 1) GnRH + TAI 48 h after PGF2α (Cosynch 48) or 2) GnRH + TAI 72 h after PGF2α (Cosynch 72). A secondary objective was to evaluate P/AI to Cosynch 48 and Cosynch 72 based on synchronization protocol (Presynch + Ovsynch vs. Resynch). Finally, the proportion of female calves resulting from Cosynch 48 and Cosynch 72 TAI was compared. Our hypothesis was that fertility would be greater for Cosynch 72 after Presynch + Ovsynch but not for Resynch TAI, and that a greater proportion of female calves would result from Cosynch 48 than Cosynch 72 TAI.
PARTICIPANTS: Individuals: Ryan A. Sterry, graduate research assistant Paul M. Fricke, PI/PD Collaborators Phillip W. Jardon, veterinarian and consultant Brian Ryzebol, dairy producer
TARGET AUDIENCES: Target audiences for this project include: bovine practitioners, dairy producers, dairy consultants, the artificial insemination industry, county agriculture agents.
PROJECT MODIFICATIONS: None.
Impacts
Overall, pregnancies per AI (P/AI) did not differ for cows receiving Cosynch 48 (29 %) vs. Cosynch 72 (33 %). Furthermore, treatment did not affect P/AI for cows receiving first postpartum TAI after Presynch + Ovsynch, for cows receiving second and greater TAI after Resynch, or the proportion of female calves born. In conclusion, delaying the second GnRH injection and TAI from 48 to 72 h after the PGF2α injection of Ovsynch did not affect P/AI or calf sex ratio. The lack of a difference in fertility between these Cosynch protocols may offer more flexibility for implementing a systematic synchronization protocol when a Cosynch strategy is used. These results have been disseminated to dairy producers, veterinarians, and county extension agents and potentially affect reproductive management of 14,000 dairy producers, 500 dairy veterinarians, and 1.2 million lactating dairy cows in Wisconsin.
Publications
- Sterry R. A., P. W. Jardon, and P. M. Fricke. 2007. Effect of timing of Cosynch on fertility of lactating Holstein cows after first postpartum and Resynch timed AI services. Theriogenology 67:1211-1216.
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