Partnar Animal Health, Specializing in Bovine, Canine and Equine Reproduction Supplies
We sell everything you need for Bovine, Equine and Canine Semen Collection, Embryo Collection & Transfer and Artificial Insemination
Research Update
CanFreeze Canine Semen Extender
CanFreeze Canine Extender was tested in Dr.Carlos Pinto’s lab at the North Carolina State
University College of Veterinary Medicine.
Partnar developed seven different freeze extenders and asked Dr. Pinto to evaluate these and then
take the most promising formulation and test it against the commercial canine extender
commonly used in his lab.
The CanFreeze Extender is a three step ready to use extender preparation and represented the best
Partnar formulation based on the screening tests conducted by Dr.Pinto.
Five different methods of evaluation the semen were utilized these included visual motility,
CASA motility, membrane integrity, Spermac (acrosome %) and viability.
Ejaculates were collected from stud dogs and pooled for analyses. Ejaculates were obtained by
digital manipulation and collected into a plastic liner connected to a 15-mL centrifuge tube.
Immediately after collection, the pooled semen sample was processed for determination of
concentration and motility parameters using a computer-assisted sperm analyzer (CASA, IVOS
Version 12; Hamilton Thorne Research, Beverly, MA). Viability was assessed by utilizing an
eosin-nigrosin stained sperm smears under oil and visualized using light microscopy at 1000 x
magnification. The hypoosmotic swelling test of sperm was carried out by adding 10 ul of semen
to 100 ul of 100 mMol hypoosmotic sucrose solution and immediately analyzed under phase
contrast microscopy at 400 x magnification. Semen smears were analyzed using Spermac stain
(Conception Technologies, San Diego, CA) to determine the percentage of cells with and without
acrosome. Processed semen was loaded into 0.5 mL plastic straws and frozen in liquid nitrogen
vapor, 2 cm above the liquid nitrogen level for 10 min, before being plunged into the liquid
nitrogen for storage. For each extender, one straw was randomly thawed by immersion in a water
bath at 37 °C for a minimum of 30 s.
Extender
N
Mean Visual Motility
Mean CASA Motility
Mean Membrane Integrity
Mean Acrosome %
MeanViability
CanFreeze
10
57.50 ±8.9
74.00 ±14.2
74.25 ±6.7
97.00 ±3.1
91.19 ±3.9
Positive Control
10
57.50 ±13.8
71.00 ±15.0
72.40 ±10.0
96.75 ±3.0
88.56 ±5.4
No significant statistical differences were detected among the three different extenders using a one way repeated
measures analysis of variance.
Discussion
The CanFreeze extender was effective in these preliminary lab studies. Further studies assessing
litter rates will be published shortly.
The two biggest differences between these two extenders were found in terms of convenience.
The Partnar CanFreeze Extender dilution rate is 1:1 making the calculation easy whereas the
positive control is 1:3-1:5. In addition of egg yolk must be prepared and added to the positive
control extender whereas the CanFreeze Extender is ready to use, not requiring additional egg
yolk.
