RAMSEM is a registered semen collection centre.
Sheep and goat semen are collected and freeze for the owner and also to make available to the small-stock industry.

Advantages of Frozen Semen for the studbreeder.
More ewes can be done with semen from a single ram. Several co-owners of one expensive ram can still make full use of the ram. Frozen semen is a good insurance for a ram – preservation of genetic material. Genetic progress – Semen from rams proven on merit, based on performance testing of their progeny, can be distributed throughout a country and many studbreeders can benefit from a national program. More economical to buy semen from a few top stud rams than to invest heavily in only one expensive ram. AI programs can be planned and executed properly – breeders know exactly how many doses of semen are available.

Semen Collection by Artificial Vagina.

This is the first step that has to be mastered to do AI on a sustainable basis. Both the semen collector or operator and rams need to be well trained. The operator has to know his rams, get them tame and used to him – feed and water them. Rams must be used to be put in pens and to be handled regularly.

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For semen collection you need a fixed routine. Put a teaser ewe in a neck clamp and introduce the ram for short intervals until the ram mounts. Identify temperament of each ram. Dominant rams easier to collect. Spend more time with rams of shy and wild temperament. Note 5 stages of collection: Preplay; Erection; Mounting; Ejaculation; Dismount and Rest. Artificial vagina (AV) is an imitation of the vagina of the ewe and provides thermal (temperature) and mechanical (pressure) stimulation to the erect penis of the male to cause ejaculation. The AV consists of an outer casing of rubber or plastic 15-20cm x 5-6cm and an inner liner made of rubber or latex. The liner is folded back and secured over the end of the casing. At one end a sterile calibrated semen collection glass is inserted. The space between the casing and liner is filled with warm water through a tap in the casing. The vagina can also be inflated through the tap to excert more pressure. The temperature on the inside of the liners should be 42°C -45°C - this is a critical aspect of successful collection. When the AV is filled with water of 50°C-55°C – this usually provides correct internal temperatures. Temperature of surroundings affects temperature of equipment and adjustments have to be made. Check with a thermometer to find the correct inside temperature and water temperature. To prevent cold shock, the collecting tube should be warmed to 30°C-37°C before collections. When the ram mounts the sheath is gently grasp and the penis is deflected onto the open end of the A.V. A vigorous upward and forward thrush signifies that ejaculation has occurred.

The A.V. is turned with the collecting glass downwards, the pressure of the liner is released and the glass with semen placed in a warm bath at 30°C-34°C.  

 
Collection of Semen by Electrical Stimulation.
Electrical stimulators with a bipolar rectal electrode that gives a 10-15 Volt output. The ram is restrained in a lateral position. Straightening of the sigmoid flexure, extends the penis and the glans penis grasped and hold with a piece of gauze swab. The rectal probe is lubricated and inserted into the rectum

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to a depth of 15-20cm, taking care to avoid injury. The rectal probe is applied towards the floor of the pelvis and short stimuli are applied with intervals. The glans penis shows congestion and with the correct stimulation semen is collected in a prewarmed and sterile tube.
 
Handling and Examination of Semen.

Semen is very sensitive, especially, for cold shock.All glassware for collection and handling must be clean, sterile, dry and warm (minimum 30°C). Work in a clean, enclosed area, protected against sun, wind, dust and insects. Directly after collection the tube with semen is put in a water bath at 32°C-34°C. Each semen sample is examine for the following: 1) Volume : This is assessed by a calibrated collecting glass. Semen volume varies from 0,3ml to 2 ml with an average of 1 ml. Variation due to individual rams, size of testes, age of ram, frequency of collection, feeding, condition and health of ram. 2) Density and color : Density or consistency is an indication of the concentration of the semen.

Density Concentration (number of spermatozoa (x109) per ml.)
Thick creamy Creamy  Thin Creamy Milky  Thin Milk Watery 5,0 (4-6 x 109)  4,0 (3,5-4,5 x 109) 3,0 (2,5-3,5 x 109)   2,0 (1-2,5 x 109) 0,7 (0,4-1,0 x 109)       Insignificant 
 
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Color:  Ram semen – white to pale cream.  Buck semen: White to yellow              Presence of blood – pink color  Contamination or infection: Grey or brown color. image
3) Wave motion and Motility :
Assessment of wave motion is the simplest test for motility of fresh undiluted semen. Good wave motion can be seen in the collection glass with the naked eye. Under a microscope a scoring system from 0-5 is assessed for each undiluted sample. 
 Score  Class      Description
 5 Very Good  Dense, very rapidly moving waves  90% or more of the spermatozoa are active.
 4 Good  Vigorous wave movement but not as rapid as for score 5     70-85% of sperm cells are active.
 3 Fair  Only small, slow moving waves 45-65% of sperm cells are active.
 2 Poor  No waves are formed but some movement of sperm is  visible.20-40% of sperm cells are alive but with poor motility. 
 1 Very poor  Only about 10% of spermatozoa, show signs of live. Only weak movement.
 0 Dead   All sperm cells are motionless.
With a good phase contrast microscope equipped with a warm stage, a drop of diluted semen under a cover slip can be examined for progressive motility, percentage of live and dead sperm and also an assessment of the morphology of the sperm.

4. Further tests on semen.
Haemocytometer and colorimeter for more accurate assessment of   concentration of semen. Stained smears to examine for sperm morphology and  presence of infection. 

Freezing of Semen by the Pellet method.
For one-step freezing, good quality semen is diluted at 30°C-34°C with the prepared diluent for freezing. Only the best samples are diluted 1+4. The diluted semen is cooled in a fridge to 5°C over a period of 1½-2 hours. A block of dry ice (solid CO2 at-79°C) is required. Holes are engraved in the surface and semen at 5°C is pipetted in 0,2ml volumes into the holes on the dry ice surface. It remains on the dry ice for 2-3 minutes and frozen pellets are transferred to liquid nitrogen at -196°C. Pellets are stored in cryo tubes (Nunc-Denmark) or Hexa goblets (IMV – France). ID of the Ram and date of freezing is written on the tubes. One pellet from each batch is thawed the next day and a proper evaluation is done with a good phase contrast microscope equipped with a warm stage at 37°C. Only batches of semen with a progressive motility of 35% are kept for AI. An incubation test, where thawed semen is kept for 2-4 hours in a water bath at 37°C, is useful as an additional quality test. One pellet of 0,2ml with a maximum dilution rate of 1+4 and with good post thaw motility is regarded as a semen dose/ewe. Semen count of 20 million live progressive spermatozoa.