Sheep / goat insemination

Artificial insemination (AI)


Reasons to apply AI and comparison with other, existing mating methods

One of the basic benefits is better use of a ram or a buck. Compare the following mating systems:

1) Group mating: 3% of rams with sheep over a 6 week period. It takes 30 - 40 sheep per ram during this period (season).

2) Mating from the hand: Sheep in estrus are separated and brought to the ram. Ram is able to mate 5 - 10 sheep a day or every other day. The mating is mostly once and is monitored. One ram can pair 20 - 30 sheep / week. Workforce engagement is required, that is, investing time in observing, extracting and recording of mated sheep.

3) AI with fresh semen, cervical method: Sperm are taken on a farm. Ten sheep can be inseminated with one ejaculate. Basically, two consecutive ejaculates are collected at intervals of few minuts (often 15 - 20 minutes). On average, about 20 sheep are inseminated per ram per day.

4) Freshly chilled semen, cervical method: Fresh sperm cooled to 15°C (French experience; shorter distance from center to farm and shorter transport period, semen is stored 8-12 hours) or up to 5°C (e.g. Australia - due to long distances, semen is stored for up to 3 days in this way). The number of inseminated sheep per ram is, on average, about 20 sheep.

5) Laparoscopic intrauterine AI with fresh or frozen sperm: Only 20 million live sperm are required for fertilization (Australian recommendations) or 50-150 million (European recommendations). Up to 100 sheep a day can be inseminated with fresh semen on a daily basis. With frozen semen, an experienced operator can inseminate up to 300 sheep a day (the limit is the speed of insemination, not amount of semen).

 

There are three techniques of artificial insemination:

- vaginal insemination,

- cervical insemination and

- laparoscopic insemination.

AI with frozen semen with vaginal insemination was developed only in Norway. The insemination is carried out in sheep that have spontaneus oestrus. Otherwise, 
in all other countries it is done exclusively with fresh semen.

Goat 
insemination with frozen semen with vaginal method is a generally accepted in intensive goat farming in developed countries where genetic progress is very important. The system of selection, control, production of semen, insemination and preparation of females must be brought to the highest level. The system does not suffer any improvisation.
 
 
 
 Cervical insemination of sheep and goats in Serbia

 Cervical insemination with fresh sperm


The basic equipment consists of a speculum with a built-in light source and pipettes connected to a 1ml syringe (plastic disposable straws are popular in Australia, New Zealand, USA). The French method (IMV Biotecnology) is using mini straws and AI sheats, similar to cattle, only smaller in size (represented in our country).

The animal is restrained by lifting hind legs over the rail and with head hanging down. The height should be 80 - 90 cm and the front legs should remain on the floor. One helper stands next to the sheep and secures the hind legs. Vulva of the sheep is wiped with a cotton swab, cloth or handkerchief. The speculum is slightly lubricated with a non-toxic semen lubricant and carefully introduced into the vagina to a depth of 10 - 13 cm. The opening of the cervix is ​​easily recognizable (picture below). There are large differences in the size and shape of the cervical aperture between individual females. In young sheep it is sometimes seen only as a cleft at the entrance of the vagina, while in older sheep the cervix is ​​usually protruding into the vagina. The opening of the cervix must be lifted by the tip of a pipette. An attempt should be made to find a space between the folds of the cervix.
 
 
 
 
The inseminator should attempt to insert the pipette into the cervix without using force. The semen is deposited in the cervix by pushing the plunger. The speculum is pulled first and then the straw to prevent reflux of the semen. Extruding semen deeper than 1cm into the cervical canal in sheep is rarely possible. It is far easier to achieve deep penetration or even intrauterine insemination in goats. Complete penetration can be felt by a lack of resistance. Avoid pushing AI sheat forcibly as this can cause damage to the cervical duct.
When a large amount of mucus accumulates in the vagina or when mucus covers the cervix, then the vagina must be emptied. The helper lifts the front end of the sheep up high and the mucus is drained out through the speculum tube.
Instruments must be desinfected before inseminations. The speculum must be cleared between each sheep. Pure alcohol must be used regularly to clean and disinfect instruments. Mild disinfectants can be used to rinse the speculum. Rinse again with clean water as disinfectants are harmful to the semen. Do not touch the tip of AI straws with hands. The tip of speculum should be wiped with gauze before introduction to next sheep. The fresh semen is diluent in extender heated to 30°C - 34°C. Boiled cow's skim milk or UHT skim milk can be the most suitable extender used on farms unless you have a commercial extender on hand.
The conception depends on the number of motile sperm, not the volume. Extender is used to prolong sperm life and to increase their volume for easier AI. Creamy density and motility sperm scored with 5 and 4 can be diluted 1 + 2 to 1 + 3. The insemination dose is 0.2 ml / sheep. Semen of low cream density and motility of 3 are only diluted 1 + 1. A solid result is expected if 0.5 to 0.1 ml of undiluted sperm is used to inseminate sheep within 0 - 20 minutes after collection.
 
AI with fresh chilled semen
Using the same technique. Semen is only taken from a thermos bottle or under a gel pack at 15 ° C or 5 ° C, respectivelly.  
 
 
Laparoscopic insemination
 
What is Laparoscopic Insemination?

Laparascopy enables artificial insemination of sheep directly into the uterus, via the abdominal wall, with minimal surgery. The laparoscopic insemination procedure was first applied by Australian researchers in 1982, which revolutionized the technique of sheep insemination. This procedure requires expensive equipment and a trained crew. The "RAM GEN" center has three trained and experienced veterinarians who apply this technique.

In sheep, the cervix is ​​an anatomical obstacle that prevents the 
semen depositing directly into the uterus during vaginal or cervical artificial insemination with a pipette due to annular folds of the cervix.

As a result, one-fold higher sperm concentrations are needed, which will be sufficient for fertilization compared to laparoscopic techniques. Better results can be obtained in goat insemination because of the possibility of deeper penetration through the cervix. Laparoscopic technique avoids the cervix as an anatomical barrier, and the semen is directly injected into each horn of the uterus. There are papers indicating that a single horn application is sufficient. This is essential for the technique of fertilization with frozen semen in sheep, precisely in order to achieve a sufficient number of vital sperm.
Laparoscopic AI is also used in the insemination of sheep in superovulation for embryo transfer (then double insemination is desiderable).

Advantages of using laparascopic insemination:
• Fertilization success with LAI is similar to natural mating (laparoscopic AI with fresh semen) and ranges between 75% to 85%. With frozen semen, AI success ranges from about 60 - 75%. If natural cycles are used, 5-10% better success is expected than only hormone-induced cycles, but this method is not used in Serbia because of small flocks. The reason is that not all sheep respond to hormone cycle induction.
• A large number of sheep can be inseminated in one day (better organization of lambing and farm work). A skilled operator can inseminate up to 300 sheep a day with either fresh or frozen sperm / semen. When using fresh semen, up to 150 sheep with one ram's sperm can be inseminated. Only 20 million motile sperm are needed for laparoscopic VO versus cervical / vaginal insemination, where 150 million are needed.
• More precise lambing period and organizing farm work in a period associated with other activities (eg sowing, harvesting, etc.).
• Better care of lambs, possibility of lambing and redistribution of lambs, better dedication to work, round-the-clock production, uniform quality.
• Frozen semen can be imported or exported more easily than live animals.
• Rams are of proven health status and fertility. Serum positive findings (positive rams for Medi visna, Brucella ovis, chlamydia, paratuberculosis was detected in 16% of licensed throats), with general and genital abnormalities, up to 20% of rams can have some of the defects that can lead to impaired fertility or its complete unusability (Milovanovic et al., 2011).
• Holds fewer rams.
• Sheep and goat breeders can use laparoscopic AI whenever is favorably in their breeding programs.
• When frozen semen is used, more sheep can be inseminated with semen from one common ram. It is possible for several co-owners to acquire one expensive ram, to split the cost of the acquisition and to use it more intensively.
• Frozen sperm is a good security for the owner, in terms of preserving genetic material for a number of years, as well as being able to trade in semen of excellent genetics.
• Rapid genetic progression - Semen of proven rams based on good traits and based on progeny testing can be distributed throughout the country and many herd breeders can benefit from it. It is more economical to buy semen from several top rams than to invest money in just one expensive ram.

The use of frozen sperm provides the wider range of available genetics.
 
Disadvantages: The technique can be too expensive for commercial sheep and goat breeders. It requires farmers ’commitment in terms of proper preparation, care and nutrition. Trained farms are happy to use this method continuously.

Equipment:

The equipment consists of:

• Endoscopic light source and fiber optic cable;

• Two sets of trocar and cannula;

• air pump with filter and latex tubes (for inflating the stomach);

• Transcap and aspic (to insert semen with the aid of a short sharp needle into the lumen of both uterine horns);

• Two or three special laparoscopic cradless (to fix the sheep to the back and to tilt at an angle of 45 ° with the hind legs up).
 
 
 
Technique: Sheep should be fasted 24 hours before insemination and should not drink water for at least 12 hours to reduce rumen and bladder contents. The abdomen is prepared by haircutin, shave (if necessary) and disinfection. The trocar is gently pierced by the abdominal wall 7 - 10 cm ventrally from the udder and 5 - 10 cm on each side from the middle of the ventral line. The scalpel can be used to make a small 1 cm incision on the skin, thus facilitating entry. The 7mm trocar and the cannula connected to the air pump are first introduced into the abdomen. The abdomen is inflated slightly to create space in the abdomen and reduce the possibility of injury to the internal organs. The introduction of the first trocar and cannula should be well controlled. The sharp trocar is pulled out as soon as the abdominal wall is pierced. Both the trocar and the cannula are inserted after the air is blown in, for safety reasons. The semen is deposited in each horn of the uterus about half the length of the body of the uterus. About 0.1-0.2 ml of diluted semen (0.2-0.4 ml total) is applied per horn. The instruments are withdrawn and placed in a disinfectant between each animal. An antibiotic spray or disinfectant is applied to both wounds. A professionally performed procedure does not result in further reproduction failures, so this procedure can be repeated without any fear. Occasional bleeding may be caused by perforation of the subcutaneous blood vessel. Wound suture or use of blood vessel clamps are rarely need. Deaths occur when the abdominal aorta is punctured with uncontrolled insertion of the first trocar. It is possible to pierce the rumen as well as the full bladder. Therefore, operators should be well trained.
 
 
 
 
 
Upon completion of insemination, sheep are given food (and a concentrated portion of the meal) and water. About 5-10% of sheep do not reach the food within a few hours but this condition stabilizes within 12-24 hours. If it lasts longer, antibiotic therapy with analgesics and vitamins should be given (give us a call).

Success of the program: In order to achieve good results, the breeder must work as a team with the AI Center and veterinarians in order to make this program successfully, well planned and implementation.
 
There are 4 basic requirements for successful reproduction:
• The presence of vital, quality sperm of ram semen;
• production and release (ovulation) of healthy ovine ovum cells;
• a favorable environment for sperm and egg cells to fuse so that fertilization can be maintained;
• a favorable environment where a fertilized egg (zygote) can grow and develop.

Poor AI results occur when one of these basic requirements is not met. From this it is clear that a breeder using a laparoscopic AI will determine the success of the program through the management and feeding of the herd.

In our conditions, the presence of moldy foods, lack of vitamin-mineral supplementation and low body condition scoring are the main reasons for poor fertilization success.
 
 
Moldy food used on the farm can cause up to 80% of sheep rebreeding after natural or induced cycle 
 

Place for laparoscopic insemination

           It is optimal to perform AI in a covered place, with concrete flooring, protected from sun, wind and dust. The sheep are tied into a solid laparoscopic cradle with small wheels. It is optimal that the space is with concrete flooring to allow the cradle to move freely. It is necessary to have two or three small boxes near the working area into which the sheep will be sorted before and after AI. A reliable power supply with 220 volts is required as well as a light source. Orientationally, a double garage work area as well as one kitchen table (or two if farm semen have to be taken on a farm) and one chair is required. 

Conclusion Laparoscopic insemination with fresh or frozen semen has become essential and integral to the controlled rearing of sheep and goats and provides valuable practical opportunities to improve reproductive efficiency and genetic progression. Please contact the "RAM GEN" center for more information.
 

The record number of live born lambs is 7 (Hancko Đerđ, Kula, Suffolk breed).

 

One example of successful implementation of laparoscopic insemination of domestic sheep in the Republic of Serbia: 9 sheep - 19 lambs (same age) (breeder Mićuka Milutinović, Lojanice, Vladimirci municipality)