Respiration rate during development

Please Note:  Our current instrument does NOT perform respiration measurements of oocytes or embryos.  These results refer to previous reseach projects.

 

 

Respiration rate measurements were performed for 114 bovine embryos every two hours from 24 hours after fertilization to 144 hours after fertilization. Data representing results from individual embryos as well as general patterns reoccuring in a number of embryos are shown below. 

Individual respiration rate monitoring

The upper panel shows the respiration rate of one competent embryo developing to blastocyst. The gradual increase in respiration rate occurred at the time when the embryo switches from translation of maternal genes to embryonic gene transcripts. The respiration rate increases further during the morula stage until a high level of about 1.2 nl 02/hr is reached for the expanding blastocyst.

 

The respiration rate develops differently in embryos with arrested development. In some cases abrupt stepwise patterns were observed (mid panel) while in other cases a gradual decrease in respiration rate is observed (lower panel).

Pattern emergence in respiration rate measurements

The respiration rate measurements of all 114 embryos were quantified and analyzed as a whole.

 

Curves of all the embryos that developed into blastocysts are shown in green.

 

Measurements in empty wells are shown as dark blue curves. Among the embryos that did NOT develop into blastocysts at least three qualitatively different patterns were observed: ranging from constant respiration rates (light blue), through gradually decreasing rates (red) to more abrupt changes in respiration rate (orange).

 

Any abrupt decrease in respiration rate was normally preceded by a marked increase in respiration rate, like a frantic burst of activity prior to cell death.

References

  • Data compiled in the lab of Dr. Henrik Callesen, The Danish Institute of Agricultural Sciences, Denmark 
  • see also Lopes, A.S., Greve, T. and Callesen, H. 2007. Quantification of embryo quality by respirometry. Theriogenology 67(1):21-31 (Entrez)