These studies demonstrate the importance of making sure that AI occurs at the right time relative to the synchronized ovulation in TAI protocols. References (peer-reviewed abstracts): E. C. Bowdridge, W. B. Knox, C. S. Whisnant, and C. E. Farin. Not labeled for use in goats in the United States. Third wheel: the insemination of elizabeth tchoungui. All Years Combined: Pregnancy rate for does in Heat Check group (35 of 66): 53%. At NCSU, Boer does that had kidded at least once before were assigned to either traditional estrus synchronization with AI following heat checking (Heat Check) using the AM-PM rule (if in estrus AM, breed PM, and vice versa) or the ovulation synchronization method with timed artificial insemination (NC Synch). Pregnancy rate for does in NC Synch 72 group (11 of 21): 52%.
NC Synch 72: 21 does synchronized and bred by TAI, 11 does pregnant. Half of the does underwent the NC Synch method developed at NCSU as described above, and the other half underwent a CIDR method as follows: CIDR ®* Method. The key for effective timed AI is the s ynchronization of not just estrus but also of ovulation (egg release). The times between drug treatments were changed to better fit the reproductive responses of goats. All animals were bred by timed AI on day 17. Third wheel: the insemination of elizabeth nj. If an AI technician is being hired, a single trip can be scheduled. After the artificial insemination breeding period, all animals were returned to the flock and managed through the standard operating procedures for the farm. Blood samples were collected 31 days after insemination to determine pregnancy status (BioPRYN® BioTracking, LLC). The remaining does were bred using the NC Synch with TAI method described below: NC Synch with TAI Method.
Data on kidding, including number of females kidding to AI breeding date, number of kids born, number of kids born alive, and twinning rate, were recorded. The results are shown below: Heat Check: 22 does synchronized, 18 bred, 12 does pregnant. Estrus synchronization combined with artificial insemination (AI) is used regularly in cattle and has been useful for breeding management. In recent research and demonstration projects at North Carolina State University (NCSU) and North Carolina A&T State University (NCA&TSU), ovulation synchronization methods for timed AI were compared. Estrus synchronization reduces the amount of time required for checking estrus (heat) before AI. CIDR removed; intramuscular injection of 3 cc Lutalyse and 2. Whitley, N. C., C. Farin, W. Knox, L. Townsend, J. R. Horton, K. Moulton and S. Third wheel: the insemination of elizabeth i 1562. Nusz. Differences between years is not surprising given differences in weather and other variables that can change from year to year, though the exact reason for the much lower rates in Year 3 is not known. Some advantages to timed AI include: - No heat checking is used. Comparison of two ovulation synchronization methods for timed artificial insemination in goats. Year 3 (2009-2010): Heat Check: 25 does synchronized, 21 bred, 8 does pregnant. Heat Check (18-24 hr. Intramuscular injection 3 cc Lutalyse. The same technicians did the inseminations (with equal numbers for each technician in each treatment group).
All breeding can occur on a single day that is selected by the farmer and/or AI technician, allowing for purchase and use of semen without long-term storage. A follow-up study was conducted at NCSU using 87 Boer and Boer-crossbred does that were divided into four treatment groups: Heat Check method described above, CIDR Method described above, NC Synch with TAI at 48 hours after the second Lutalyse injection (NC Synch 48) and NC Synch method with TAI at 72 hours after second Lutalyse injection (NC Synch 72, the NC Synch protocol used previously). Breed (AI) by AM-PM rule. All does were exposed to bucks via fence-line contact prior to the start of any treatments. Based on the research and demonstration work of Dr. Charlotte Farin and William Knox, North Carolina State University, and Dr. Niki Whitley, The Cooperative Extension Program at North Carolina A&T State University.
These technologies would also be useful for goat farmers interested in using AI to increase the genetic merit of offspring. Pregnancy rates were higher for animals treated with the CIDR method (50%) than the NC Synch method (10. NC Synch: A protocol for ovulation synchronization and timed artificial insemination in goats. Intramuscular injection 1cc Cystorelin and AI. The low pregnancy rates associated with the NC Synch method in the Upper Mountain Research Station study may have resulted from an early ovulation in this group of does that had not been exposed to bucks prior to the start of the experiment. Because exposure to buck pheromones can shift ovulation timing in does that have not been in prior contact with bucks (known as the buck effect), it is important to be sure that does are managed carefully when considering the NC Synch TAI protocol. At the Upper Mountain Research Station, NCSU, NCA&TSU, and station staff conducted a demonstration and applied-research project using 38 Boer-crossbred does. Pregnancy rates based on ultrasound at 50 and 85 days after breeding.
Does were housed together and were kept from sight, sound, and smell of all bucks until day 15 when all were allowed fence-line contact to an intact buck. A successful ovulation synchronization program with timed AI would allow farmers to add new, higher-value genetics into their herd more efficiently than with estrus synchronization and traditional AI. Acknowledgments: Dr. Keesla Moulton, Elizabeth Bowdridge, Deanna Sedlak, Roberto Franco, Allison Cooper, Lorie Townsend, Ray Horton, and Joseph French. At about 50 and 85 days after artificial insemination, animals were checked for pregnancy status using transabdominal ultrasonography. This research was conducted for three years (2007 to 2010). Frozen semen from a commercial company (Superior Semen Works, Milton, NH) was used for all AI, and motility of samples was confirmed for each straw.