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