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Artificial Insemination in Large Animals. Tony Seykora University of Minnesota. Characteristics of Ejaculates. Volume (ml) Sperm / ml 10 6 Dairy Bulls 7 1250 Beef Bulls 5 1500
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Artificial Insemination in Large Animals Tony Seykora University of Minnesota
Characteristics of Ejaculates Volume (ml) Sperm / ml 106 Dairy Bulls 7 1250 Beef Bulls 5 1500 Rams, Bucks 1 2000 Boars 225 125 Stallions 90 125
Effect of AI to Dairy Industry Parameter 1945 1985 Change Dairy cows (no.) 25 mil 11 mil -56% Milk production (lbs.) 120 mil 140 mil +16% Milk/cow (lbs.) 4,800 12,700 +265% Total feed -30% Feed Costs -$3 bil 80% of dairy calves born as the result of A.I.
Milk Production Record • True-Blue Duster Ihm Jen • 61,030 pounds in a 365 day lactation (3X) • ~ 167 lbs a day • Probably gave ~ 305 at peak lactation
Semen Collection • Semen used for AI can be collected by: • rectal massage • electroejaculation • artificial vagina
Semen Collection (con’t.) • The most common method of collection is the artificial vagina as this results in the highest quantity and quality of semen.
Semen Collection (con’t.) • The artificial vagina consists of a large rubber tube lined with a water holding jacket. • A receptacle for collecting the semen is attached to the end of the tube.
Semen Evaluation • After the semen has been collected, it is examined in the lab under a microscope for motility and morphology.
Semen must contain at least 40 million cells per cc before freezing and 12.5 million cells per cc after thawing to be used for AI.
After the semen sample passes a thorough evaluation, it must be processed using an extender. The extender dilutes the semen sample so it can be divided into several units for the fertilization of many eggs. The extender also dilutes the waste products produced by the sperm so the sperm remains viable.
Processing the Semen • Extender also provides nourishment and protects the semen after it has been frozen. • Common extenders added to semen include milk, egg yolk, glycerine, and antibiotics. New extenders are now developed that contain no animal products!
Freezing the Semen • Semen is frozen at a constant rate until it reaches a temperature of –320 F. • Semen is stored in liquid nitrogen tanks to preserve it.
Heat Detection Recommendations • Patience • Don’t distract cows – move quietly • At least two 45 minute sessions (early morning and late evening) • Use heat detection aids • Use secondary heat signs • mounting other females • Swollen vulva • mud on flanks or rubbed off brand
Artificial Insemination Onset of Heat Ovulation and Fertilization Sperm Capacitation 0 12 16 20 24 25 33 Hours
Semen is thawed by placing in 95 degree F water bath. • The straw is placed into the end of the AI rod and a protective sheath is put over the rod. • The plunger is locked into place.
Locating the Cervix • The technician should insert one hand into the cow’s rectum to locate the reproductive tract and cervix.
Cleaning the Vulva • The skin around the vagina (the vulva) should be cleaned with paper towels to avoid contaminating the cow when inserting the AI rod into the vagina.
Inserting the Insemination Gun • Once the cervix has been located, the AI rod is inserted through the vagina into the reproductive tract. • The rod must be passed through the three muscular rings of the cervix and into the body of the uterus.
Depositing the Semen • Once the technician is sure the rod has passed through all three rings of the cervix, the semen is deposited into the body of the uterus.
Oviduct Site of Fertilization Uterine horns Ovary Uterine body ‘TARGET’ Cervix
Kamar patches • Useful on cows you suspect may be coming into heat, but not yet showing standing heat. • Expensive ~ 1.00/ apiece • Should be used as tool to supplement visual detection not replace it
Tail Chalking • Can be prone to errors • Less labor intensive than observation • CHEAP
Other Methods • teaser gomer bulls • chin ball marker • steroid-treated cows • Pedometers
Estrus synchronization • Estrus synchronization is a management tool with several different procedures • If used properly it can increase pregnancy rate. • No matter how well used will not increase conception rate • Increases pregnancy rate by increasing service rate
Synchronization Products • Prostaglandin (PGF) • Lutalyse • Estrumate
X Follicle Corpus Luteum X Ovulation Progesterone
Synchronization Products • Progestins • Melengestrol Acetate (MGA) • Norgestomet • CIDR
Follicle X Corpus Luteum Ovulation Progesterone
Synchronization Products • Gonadotropin Releasing Hormone (GnRH) • Cysterelin • Fertagyl • Facterel
Follicle Corpus Luteum Ovulation Progesterone
Ovsynch (Timed-A.I.) Timed A.I. GnRH PGF2 GnRH 2 days 7 days 18-24 hr GnRH = $3.50 PGF2 = $3.00 Total Cost $10
Presynch GnRH 14 d 7 d 12 d 24h 48h GnRH PGF2 PGF2 PGF2 Time inseminate Cost $16
Estrus Detection and AI 2 × PGF 100 cows in herd PGF Heat detect and AI PGF -14 0 6 No. detected in estrus: 65 Synchronization Rate: 65% Conception Rate: 42/65 = 65% Pregnancy Rate: 42/100 = 42%
Timed AI CO-Synch + CIDR 100 cows in herd GnRH & AI PGF GnRH CIDR -7 -1 0 2-3 MGA No. detected in estrus: - Synchronization Rate: - Conception Rate: 60/100 = 60% Pregnancy Rate: 60/100 = 60%
Relative Price for Estrous Synchronization Products • PGF (Lutalyse, Estrumate, Prostamate): $ 2 to 3 Ave = $2.50 GnRH (Cysterelin, Factrel, Fertagyl): $ 2.50 to 6 Ave = $4.50 • Progestins (MGA, CIDR): MGA - $ 0.05 to 0.20/head/day Ave = $ 0.10/head/day CIDR - $ 6.50 to 10.00 Ave = $ 8.00
Why AI for Beef? • Disease prevention • Widespread selection of bulls • Proven genetics • Reduce costs associated with bull maintenance • Uniformity • Genetic selection of replacements improves overall cowherd genetics
Ultrasound Evaluation of Fetal Development for Twin Pregnancies ET US US US RP Live Birth D 7 d 33 d 69 d 108 d180 Birth No. of transfers 37 37 36 36 36 36 Pregnant recipients 37 30 27 24 22 21 Twins 37 17 11 9 8 7 % twins of pregnant recipients 100 57 41 38 36 33
Early Embryonic Pregnancy Detection 25 Day Pregnancy 35 Day Pregnancy 50 Day Pregnancy
Inducing Twins in Cows by Transferring Two Demi-Embryos Single Birth Twin Birth Calving percent, % 95 130 Weaning percent, % 90 120 Sets of twins 3 30 Weaning wt of twins, lb 425 425 Weaning wt of singles, lb 550 550 Ave weaning wt, lb 541.00487.50 Weaning wt/cow, lb 486.90 585 Price/lb, $ 1.00 1.05 Revenue/cow, $ 486.90614.25
% of Sows Bred A.I. • 1990 7% • 1997 50% • 2004 75-80%
Boars collected 2 to 3 times per week. 12 inseminations per ejaculate. Assuming 2 inseminations per sow equals greater than 500 sows serviced per boar.
A.I. Advantages in Swine • Saves time. • Fewer boars to maintain. • Mate animals of different sizes • Works for producers of all sizes • More offspring from boars of top genetics