Saturday, December 14, 2013
Breeding Soundness Exams
While the focus of our project is Artificial Insemination, our work first focused on the the ram by learning about breeding soundness exams (BSE). A BSE is a relatively simple test to evaluate a ram’s suitability for breeding. This test is of value to every sheep operation and is essential for rams used in AI. It consists of a physical examination, an inspection of the reproductive organs, and an evaluation of a semen sample.
Dr. Craig Zimmerly, DVM is demonstrating the correct use of a scrotal tape as part of this ram's BSE. Research has shown that rams with large scrotal measurements not only produce
more semen than rams with smaller scrotal measurements but will also have
progeny that reach puberty earlier.
The Society for Theriogenology recommends the following breeding program standard values for scrotal circumference:
Rams 8 months to 14 months
< 30 cm questionable
30 - 36 cm satisfactory
> 36 cm exceptional
Rams > 14 months old
< 32 cm questionable
32 - 40 cm satisfactory
> 40 cm exceptional
Wednesday, December 4, 2013
Performing Sheep AI on the Farm
Kathy Bielek of Misty Oaks Farm, is being coached by Dr. Dale Duerr, DVM on the proper pipette position while she inseminates one of her Katahdin ewes. This is one of 3 farms visited by our team in the past 3 months. At each farm, 20 ewes have been artificially inseminated.
Dr. Duerr, DVM and Dr. Zimmerly, DVM have taught us about performing breeding soundness exams (BSE) on rams, handling semen, prepping ewes, inseminating ewes using cervical AI techniques, and performing ultrasounds to determine pregnancy.
This project team was formed when a small group of farmers realized there was a need to not only have a biosecure method for introducing new genetics to closed flocks but also to share their genetic gains across more flocks. Although numerous research studies have been conducted on AI in sheep, the application of AI at the farmer level in the U.S. is limited. We are hopeful that this can change.
Monday, December 2, 2013
Artificial Insemination Methods Used in Sheep
Insemination of sheep may be vaginal, cervical (posterior or transcervical), or intrauterine.
Vaginal insemination deposits fresh diluted semen into the anterior of the vagina without an attempt to locate the cervix. It is the simplest and easiest method but requires a larger dose of semen and the success rates are usually less than other methods.
Posterior cervical insemination uses a pipette to transverse the vagina and deposit fresh diluted semen at the cervical opening. It is a technique that is relatively easy to perform, but is limited to fresh semen (diluted or undiluted) since conception rates are generally lower with frozen semen. It is the most common method used in sheep.
Trancervical insemination is performed by inserting a thin pipette through the cervix and depositing the sperm directly into the uterus. Because of the anatomic complexity of the ewe’s cervix, it is more difficult to perform than posterior cervical AI. This method requires a special pipette but allows the use of either fresh or frozen semen at fairly high success rates.
Intrauterine insemination is often referred to as laparoscopic artificial insemination (LAI) and is accomplished by depositing semen directly into the uterus through an abdominal incision. Conception rates are typically very high. Because LAI is an invasive procedure, it requires the expertise of a trained veterinarian which makes it cost-prohibitive and less available for producers.
Thursday, October 31, 2013
Ethnic Marketing of Lamb and Mutton
A FREE 4-PART WEBINAR SERIES
The webinar series will provide sheep producers with the
necessary skills to effectively market sheep/lamb meat to ethnic
communities in their respective market areas. The series includes four
live webinars, associated readings, activities, assignments, and group
discussions.
Developed jointly by Richard Brzozowski, Extension Educator,
University of Maine Cooperative Extension, with Susan Schoenian of the
University of Maryland Extension and Roger High of Ohio State
University.
Advantages of Artificial Insemination in Sheep
AI has not yet received acceptance in the sheep industry like it has in other livestock breeding practices. There are several reasons for this. The cost of implementing an AI program has often outweighed the economic benefit in an industry that sometimes operates at a small profit margin; the cost and maintenance of breeding rams can be relatively low; and the success rate obtained in the past has been a limiting factor due to the anatomical make-up of the ewe’s cervix and the ability to successfully utilize stored and frozen semen.
Let's explore some of the advantages of artificial insemination in sheep:
2. AI allows for easy transportation of genetic material. Semen is much cheaper to transport than entire animals and is not subject to the same risks of spreading disease. New genes could be imported from overseas and from countries which will not allow importation of live animals.
3. Semen from valuable rams may be stored for use in future years – even after death or as an insurance policy in the event of death. Additionally, when monitoring for genetic progress, the same ram can be used over several years of selection and future generations compared back to the base ram.
4. Increased efficiency of breeding. Timed inseminations allow all ewes to be mated even if they are not displaying behavioral estrus.
5. Reduction or elimination in the need to maintain rams on the farm. Small breeders could eliminate the costs and inconvenience associated with keeping a team of breeding rams - provided they can obtain semen from outside sources.
6. Prevention and control of disease by eliminating direct male to female contact.
7. Use of an incapacitated ram that might have suffered injury or become infirm and unable to mate naturally. If the semen is of sufficient quality, he can be still be used for breeding.
8. Accurate record keeping that can be helpful in increasing the accuracy of selection or to eliminate undesirable traits from a flock.
9. Synchronized or out-of-season breeding for better utilization of resources during lambing periods or where it is not possible for producers with large flocks to keep a sufficient number of males for natural mating.
10. Use of additional technology like superovulation for embryo transfer and pre-determining sex of offspring by separating X and Y chromosome bearing spermatozoa.
Evans,
Gareth, and M. Chisholm Maxwell. "Introduction to Artificial
Insemination." Salamon'sArtificial Insemination of Sheep and Goats. Butterworths, 1987. 1-5. Print.
Monday, October 7, 2013
ASI Webinar Oct 8, 2013: Reducing Labor at Lambing Time
If you haven't already registered for the upcoming ASI Webinar on TUESDAY, October 8, time is running out. Information on the webinar and the link to complete registration are listed below.
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Reducing Labor at Lambing Time
Join us for a webinar on Oct 08, 2013 at 7:00 PM EDT.
Register now! (copy and paste into your browser if link doesn't work)
Presenters:
Philip Berg, Pipestone Lamb and Wool Program Instructor Mike Caskey, Pipestone Lamb and Wool Program Instructor Minnesota West Community and Technical College, Pipestone Date: Tuesday, October 8, 2013 Time: 7:00 pm Eastern DST, 6:00 Central, 5:00 Mountain, 4:00 Pacific Host: Dr. Jay Parsons, Colorado State University & Optimal Ag Our discussion will identify keys to reducing labor at lambing. This will include labor saving watering, feeding and bedding systems ideas. Examples of warm lambing barn layouts and sheep flow will be presented. This webinar is made possible with funding support from the American Sheep Industry Association and the Rebuild the Sheep Inventory Committee.
After registering, you will receive a confirmation email containing information about joining the webinar.
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