Progress 07/01/24 to 02/12/25
Outputs
Target Audience:This grant project was targeted at commercial producers of the United State's 5 million sheep and 3 million goats (together, small ruminants). Small ruminant meat is the 4th most consumed meat product in the United States of America and unfortunately the U.S. is a current net importer of this meat, inspite of a persistent growing demand in the U.S.marketplace. In fact, the U.S. is the largest market for Australian lamb.Similarly, the U.S.A. is a net importer of milk from sheep and goats, including cheese products. Moreover, we import the majority of the wool utilized to produce clothing and such. Truely, this is unfortunate as sheep and goats provide the best sustainable source of farming as it is efficient, the animals are adaptable across ecological zones, they have minimal carbon footprint, and a lower initial investment than most other livestock. This situation arose in part due to the inability to rapidly improve the genetics of small ruminants. Genetic gain is limited by the current method of reproduction, live cover and laparoscopic insemimation. Laparoscopic insemination results in ewe death in at least 5% of the ewes and is a veterinary-mediated task, making it too expensive for commercial producers. In most livestock ,dairy and beef cattle, swine and turkeys, animals are artificially inseminated using a slender rod that is passed through the cervix and into the uterine body. This technique is performed by a trained technician and does not put the animal at risk,is cost effective and importantly, does not require prophylactic antibiotics.Economically reasonable insemination such as used in dairy cows,is a high impact reproductive technology that increases genetic improvement, allows international trading of genetics, decreases spread of disease by decreasing animal interactions and creates economic efficiencies within the commodity market of livestock production. The big problem: cervical insemination with an AI rod does not work in sheep and goats because of the tortuous anatomy of the ewe's reproductive tract! This grant project isdirected at providing an economically responsible method to inseminate sheep and goats, allowing the industry to receive the appropriate benefits, and to grow to become internationally competitive! Changes/Problems:Only minor problems were encountered to this grant project. 1) We proposed doing a tape test on abattoir cervices to determine the depth of penetration of the softening agent into the cervical tissue. Unfortunately this did not work as the oily nature of the softening agent did not allow the tape to adhere. After converation with our Project Director, Dr. Smith, we switched to a histological sectioning and staining technique. looking for oil droplets within the tissue compared to untreated tissues. We did see a statistically signficant (P<0.05) increase in oil-red-O positive droplets in treated cervical tissues. 2) We required use of a vaginal speculum during insemination as the cervix location is highly variable from ewe to ewe and even within ewe. The use of the speculum decreased potential trauma to the sheep as it allows one to visually located the cervix rapidly and to position the AI rod correctly rather than continually probingthe ewes' reproductive tract. Above all, we want this technology to be safe for the ewe. What opportunities for training and professional development has the project provided??MPTI had multiple opportunities for training and professional development as the live ewe-research was conducted at Casper College (Casper, WY). Students in the agricultural department actively participated in the research, gathering data, e getting some hands-on time with the ewes, trying to use the technology. In fact, students helped in the insemination of the9 ewes! One remarked proudly when we ultrasounded the ewe she helped to inseminate and found her pregnant, that she was now "a lamb daddy"! How have the results been disseminated to communities of interest?MPTI has reached out to various sheep associations including Sheep Genetics, USA, the Wool Growers Association to have conversations with their executive directors. In addition, outside of the grant, one of the MPTI principalss attended American Sheep Industry Association annual meeting. A conversation was held with a dozen producers, and one company involved in laparoscopic AI to share our data, and discuss their views on the research. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
During this Phase I SBIR grant, MPTI exceeded each of its objectives and moves us us a significant way to creating a low cost method to inseminate ewes with frozen semen. This then allowsthe U.S. sheep industry to make rapid genetic changes within their flocks to meet consumer demand. MPTI startedthe project with a cervical softening agent thatappearedto allow relaxation of the cervix which then allowed an artificial insemination rod to pass throughthe rigid, tortuouscervical os, through the convoluted cervical rings and into the uterine body (like AI in cattle). During this grant, we developed a commercially appropriate method to apply the softening agent. We testedover 33 differenttypes of delivery systems in abattoir tracts. We ensured that there was no significant change in sperm quality after introduction to the softening agent in its final delivery method; the final delivery method does not have a negative impact on sperm quality (objective 1b), and does not result in changes in the cervical tissue. The transition to testing on ewes in a 'ranch' type environment enabled further elimination based on practicality. By the 3rdand 4thexperiments using ewes, we were optimizing the selected delivery method.Like the preliminary data presented for the application, the softening agent proved to be transient, and in fact with the developed delivery method, the time between treatment and AI rod passage was decreased to the 15 to 30 min period from 1 hour in previous research, improving the commercial appeal for the technology.Although one goal was placement of the softening agent without visualization, the final method requires use of a speculum. With the final delivery method, the softening agent can be fully absorbed by the cervix therefore, residue was not an issueas previously anticipated. Through efficacy testing in 4 different live ewe experiments and using 6 different delivery method variants we developed an effective delivery system for the softening agent.Importantly, the finaldelivery system that was effective in allowing an AI rod to pass through the first cervical ring in 94% of ewes, through the second ring in 90% of ewes and into the uterine body in 73% of ewes(Objective 2, the seminal objective). The final and most exciting result was not a Phase I objective but was executed in preparation for Phase II; we inseminated9 ewes using our technology and had a 67% pregnancy/AI with 67% of the pregnant ewes (4 out of 6) having twins! Twinning is economically important in commercial sheep production.This practical proof-of-concept drives us forward into our Phase II grant.
Publications
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