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Collecting and Handling Semen. 4-H Veterinary Science Extension Veterinary Medicine . Objectives. Describe methods for semen collection List the steps for handling semen for freezing. Purpose Evaluation Increases economic rewards Evaluate breeding soundness Breed artificially Storage
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Collecting and Handling Semen 4-H Veterinary Science Extension Veterinary Medicine
Objectives • Describe methods for semen collection • List the steps for handling semen for freezing
Purpose • Evaluation • Increases economic rewards • Evaluate breeding soundness • Breed artificially • Storage • Increase bred animals • Reduce disease transmission
Semen Collection • Species dependent • Types • Artificial vagina (AV) • Electroejaculator • Palpation of accessory glands • Keep warm • Avoid light
AV • Rigid tubular structure • Jacket • Filled with water • Tube on end • Ideal • Good sperm quality
Electroejaculator • Sends electrical impulses • Inserted rectally • Lower sperm quality • Poor libido males
Palpation • Seminal vesecles • Epididymis • Ampulla • Vesicular glands • Prostate gland • Cowper’s glands
Bull and Ram • Collect with • Electroejaculator • AV • Palpation • Mount • Castrated animal • Cow/ewe • Dummy
Stallions • Collect with • AV • Condoms • Mount • Mare • Dummy (most common)
Boar • Collect with • AV (modified) • Gloved hand technique (most common) • Electroejaculation (anesthetize)
Dogs and Cats • Dogs • Manual collection • Cats • AV collection
Semen Evaluation • Macroscopically • Grossly • Color • Creamy, white or gray • Volume • Depends on age and species • Consistency • Concentration • Microscopically • Sperm motility • Forward motion • Concentration • Morphology
Macroscopic evaluation • Motility • Morphology • Normal sperm composed of a head, mid-piece, and tail
Abnormalities in Semen • May swim in circles or in place • Conformational problems • Primary defects • Originate in testicles more serious • Secondary defects • Acquired as sperm pass through the tubules and ducts of repro system also by poor handling • Large number of either type may result in decreased fertility
Extending • Diluted for insemination or for storage • Only highest quality of pure substances of various compounds should be used • Increases the number of females to be bred with single ejaculate • Provides energy source and protection • Extenders include egg yolk phosphates, egg yolk-citrate, tris, homogenized milk, or cream and if frozen for long term glycerol • Sometimes antibiotics are includes to prevent contamination of sperm
Storing • Cool slowly • Prevent cold shock • Preserve viability • Stored -130oC prevents crystal formation • Accomplished by liquid nitrogen process called cyrostorage • Various methods • Straws
Storing • Divided in ½ or 1 ml fractions • 20 million cells per straw • Labeled and placed into canes in canisters within liquid nitrogen tank • Canisters are numbered for records
Thawing • Quickly • Warm water • 10-30 seconds • Ice water • Few minutes