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LAPAROSCOPIC INSEMINATION IN SHEEP
LAPAROSCOPIC INSEMINATION IN SHEEP Laparoscopic AI (LAP AI) involves the insemination of ewes, synchronised with cidrs/sponges and PMSG, with fresh or frozen semen, using a laparoscope to enable insemination directly into the uterus. Artificial insemination is a precise procedure, and to achieve satisfactory results, the program needs to be followed and performed with great care. AI results are optimised by : 1. SUPPLEMENTARY FEEDING the ewes 3 weeks prior to AI. Lupins are preferable i.e. 100 gm / head / day. 2. Keep the ewes isolated from the smell and sight of rams until the cidrs/sponges are removed and the teasers are released with the ewes. 3. Ewes should be handled quietly and slowly, with minimal stress from dogs. Avoid moving the ewes unnecessarily on the day of AI and up to 4 weeks after AI. PRE-AI MANAGEMENT OF EWES Ideally ewes should be weaned at least 8 weeks prior to AI, and all routine treatments and management procedures (drenching, dipping, shearing etc.) completed prior to sponge insertion. Ewes of body condition score 3 are ideal. Ewes of body condition 3.5 plus should be run tight two months prior to cidr/sponge insertion, to ensure they are not over fat at the time of insemination. However, they should be pushed 3 weeks prior to AI to give an increasing plane of nutrition and the 'flushing' effect. "Flushing" ewes for 3 weeks prior to AI with supplementary feed, may assist in boosting the ovulation rates and therefore the number of lambs born. SYNCHRONISATION Ewes are synchronised using intra-vaginal sponges or CIDR’s These sponges contain progesterone and are inserted into the vagina for a period of 12 days. The sponge is then removed and an injection of hormone (PMSG) is administered. Two days after cidr/sponge removal AI is performed. The success of AI depends on synchronising ovulation with the arrival of viable sperm in the reproductive tract. Sponges/cidrs must be pulled from ewes and PMSG administered accurately at the time specified on the program. If for any reason the removal of sponges/cidrs is delayed, contact the AI company immediately. TIMING OF INSEMINATION Maximum conception rates using frozen - thawed semen, occur when the ewes are inseminated from around 8 hours before ovulation, and no later than 4 hours after ovulation. Ovulation in flocks after sponge removal can vary from 55 to 69 hours, therefore most ewes are inseminated between 52 - 60 hours after sponge removal.If using CIDR’s then ovulation occurs 6 hrs earlier so the time of removal has to be delayed. TEASER WETHERS These are optional. At the time of sponge insertion, wethers (10% of ewes inseminated), need to be injected with 5ml of Tesgro or Banrot. Teaser wethers aid in the synchronisation of ovulation. At sponge removal the teasers will either need harnesses ('cold' or 'soft' crayons) or branding fluid liberally applied painted onto their briskets and released with the ewes. The branding fluid will need to be reapplied each time the ewes are drafted. Marked ewes are drafted off the night before AI, and the morning of AI. The ability to identify ewes in season assists in the timing of the insemination. SEMEN QUALITY Frozen All semen is thoroughly assessed after freezing and only semen of good quality is retained for use. Frozen semen to be used needs to ordered or collected from the ram at least two months prior to AI. Fresh AI programs requiring the use of fresh semen, need to have the ram trained and back - up frozen semen collected at a semen collection centre. All rams must be rested for at least 3 days prior to a fresh AI day. CLIENT RESPONSIBILITIES AT INSEMINATION Facilities AI is conducted inside the shearing shed or similar shed with basic sheep handling facilities with a smooth, solid floor. Electricity is essential and a stable, wool table or large trestle table is required for equipment. Fresh water is also required, about 2 buckets. Labour At least two fit people are needed to load ewes into the cradles. If ewes require ear tagging or brand ID, extra staff are necessary. Livestock Ewes have to be removed from feed and water 12 hours prior to insemination. Access to water and hay after insemination (especially if it is hot and the ewes have a long distance to walk to the paddock) will assist in reducing the stresses associated with AI. PROCEDURE FOR THE USE OF CIDRS Cidr insertion Place applicator in a non-irrating antiseptic solution, such as an iodine solution. Cidrs are “Y” shaped, and the short ends push together, with the tips protruding from the applicator. Gently place the applicator (with cidr in place), into the vagina of the ewe. Depress the applicator handle to release the cidr into the vagina. Slowly pull the applicator out, ensuring that the cidr stays in place. (Sometimes the cidr cord can be caught in the applicator and the cidr dislodges as the applicator is removed.) Wash the applicator between each ewe and ensure that the procedure is conducted in a clean environment. Note: For Maiden or Dry Ewes, ensure that the cidr is pushed past any constriction in the mid vagina. Do not apply excessive pressure which can cause damage to the ewe. Cidr Removal Cidrs must be removed and P.M.S.G injected into the muscle of the hind leg prior to the time indicated on the date allocated. To remove the cidrs, pull the cord backwards and downwards. The cord can be drawn up into the vagina, hence if the cord is not visible carefully insert a clean finger into the vagina and locate it and remove the cidr. If the cidr cannot be removed, or located, don't administer P.M.S.. Identify the ewe/s and the problem will be treated on the day of AI. Cidrs need to be disposed carefully. Either burnt or deeply buried ASAP. INSTRUCTIONS FOR HANDLING P.M.S.G. KEEP P.M.S.G. REFRIGERATED Mixing the PMSG the evening prior to its use is convenient. Only make up the amount required the next morning. Withdraw 3mL of sterile water from the bladder pack and inject it into the small bottle of freeze dried Pregnacol. Mix thoroughly to dissolve all of the hormone. Draw up all of the dissolved hormone and place it into the bladder pack of sterile water. You will be notified on the dosage required (usually between 1.5-2.0 ml / ewe). Check the accuracy of your auto vaccinator, set dosage and attach the made up bladder pack. P.M.S. is injected intramuscularly into the rump or hind leg of the ewe. POST AI MANAGEMENT 1. Ewes should be handled gently at the time of AI and allowed to walk quietly back to their paddock. 2. Feeding The ewes should not be disturbed for four weeks and a change in diet should also be avoided during this time. Keep the ewes on maintenance feeding levels. Don't over feed 3. Back up rams can be released 14 days after AI. Ewes not holding to AI will start returning to oestrus 15 - 19 days post AI. 4. Scanning Pregnancy scanning (ultra sound) 45 days after AI or back-up ram removal, allows for single / twin feeding and re-mating of dry ewes. Contact AI centre for further details 5. Lambing Ewes holding to AI will lamb over a 4 -5 day period with a peak around day 145 ( EARLIER than natural mating). 6. Results Standard forms will be provided to aid data collection. Send us your results and any interesting comments!! Without these we cannot improve. GOOD LUCK ☺!
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