A NIFA-funded dual purpose, dual benefit grant with the National Institutes of Health (NIH) researched the effects of a molecule called colony stimulating factor 2 (CSF2) regarding the development of the early bovine embryo. It has yielded some striking results that could have far-reaching consequences for animal production. 

 

CSF2 is a regulatory molecule produced by the reproductive tract of the cow and other animals. One function of CSF2 is to modify development of the early embryo. In the human and cow, addition of CSF2 to culture medium of embryos produced in the laboratory can enhance the likelihood that an embryo can survive to term after transfer into a female. 

 

Researchers demonstrated that actions of CSF2 on the early embryo can have long-term effects that extend into life after birth. They also observed that heifer calves born as a result of transfer of an embryo exposed to CSF2 from day five to seven of development, gained weight more rapidly in the first 13 months of life than calves derived from embryos not exposed to CSF2. While there was no difference in birth weights between groups, CSF2 heifers grew more rapidly thereafter. At 13 months of age, CSF2 heifers weighed 88 lb more than control heifers. It is likely that CSF2 acted on the early embryo to cause long-term changes in function of genes involved in biological processes controlling postnatal growth.  

The practical consequence of this work is that it may be possible to improve the ability of a cow or other farm animal to produce meat or milk by exposing it to signals like CSF2 during early pregnancy when it is still an embryo of only 50 to 150 cells.  If these results are borne out with further research, manipulation of signals like CSF2 could program the embryo for later success after birth. The result would be increased profitability and sustainability of production of animal-based food products.