Latest Pig Industry News
New Aspects of Boar Semen Freezing Strategies
GERMANY - Research paper published by R. Großfeld and colleagues at Friedrich-Loeffler-Institute in Neustadt, Germany. They successfully investigated ways of improving fertility after cryopreservation of boar semen.Although cryopreserved boar semen has been available since 1975, a major breakthrough in commercial application has not yet occurred. There is ongoing research to improve sperm survival after thawing, to limit the damage occurring to spermatozoa during freezing, and to further minimize the number of spermatozoa needed to establish a pregnancy. Boar spermatozoa are exposed to lipid peroxidation during freezing and thawing, which causes damage to the sperm membranes and impairs energy metabolism.
The addition of antioxidants or chelating agents, e.g. catalase, vitamin E, glutathione, butylated hydroxytoluene or superoxide dismutase, to the still standard egg-yolk based cooling and freezing media for boar semen effectively prevented this damage. In general, final glycerol concentrations of 2-3 per cent in the freezing media, cooling rates of -30 to -50ºC/minute, and thawing rates of 1200 to 1800ºC/minute resulted in the best sperm survival.
However, cooling and thawing rates individually optimized for sub-standard freezing boars have substantially improved their sperm quality after cryopreservation. With deep intrauterine insemination, the sperm dose has been decreased from 6 to 1x10(9) spermatozoa without compromising farrowing rate or litter size.
Minimizing insemination-to-ovulation intervals, based either on estimated or determined ovulation, have also improved the fertility after AI with cryopreserved boar semen.
With this combination of different approaches, acceptable fertility with cryopreserved boar semen can be achieved, facilitating the use of cryopreserved boar semen in routine AI programs.
Großfeld R, Sieg B, Struckmann C, Frenzel A, Maxwell WM and Rath D. Institute of Farm Animal Genetics, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health (FLI), Hoeltystrasse 10, 31535 Neustadt, Germany. Theriogenology. 2008. Sep 4.
ThePigSite News Desk
Related news items:
Third TOPIGS Import into China in Three Months
Breeding Success and Maximising Returns
EU Sets New MRL for Altrenogest
Project on Gender–Sorted Semen Ended
From the Wallingford Pig Study Group to PIC
Related News Categories: Breeding and Reproduction, Genetics, Artificial Insemination
More of the latest Pig Industry News
Action Taken to Ramp Up Abattoir Inspections
FAO Food Price Index Rebounds in January
OleoServ Takes over Harles & Jentzsch Assets
US Pork Export Forecast is Unchanged- Public Resistance Ousts GM Crops From EU
Nutreco Achieves Excellent Progress in 2011- Animal Welfare: The Right Thing to Do
New Zealand Pork Seeks New CEO
Two Cases of ASF in Wild Boar- 2011 Pork Imports Higher Than a Year Ago
