Kitchen Wrap and Calcium: Changing the Way Baby Chicks Are Developed

By: Amy Cryer

Kitchen Wrap and Calcium: Changing the Way Baby Chicks Are Developed! Many people ask if we are eating baby chicks when we eat eggs, and the answer to that question is that the eggs that we buy and the ones from farms are unfertilized eggs that have not been developed enough to develop a baby chick. A study conducted by Bruce Dunn at the Medical College of Wisconsin investigated the impact supplemental calcium has on the hatch rate and hatching mass of chick embryos (baby chicks) in a shell-less culture system. The main purposes of this study were to confirm that baby chicks are capable of hatching when suspended in F.O.R. wrap (polymethyl pentene plastic wrap), to develop an incubation system that will allow numerous cultures to be maintained coexisting in a controlled culture, and to compare the wet mass, dry mass and length of the right third toe of cultured and in ovo (in embryo) hatchlings.

Dunn conducted his experiment using a shell-less culture system which involves culturing baby chicks with associated yolk and albumen (whites of the egg, contains proteins) outside of the eggshell membranes and eggshell. This yolk inside of the baby chick's eggs is fertilized and not the same as the unfertilized ones that we eat. Dunn mentioned that there are operations that can be performed or injections given on specific parts of the embryo to observe changes in the behaviour, growth, and heart rate of the chicks without having to sacrifice the cultures. Some cultures received just water and the remaining cultures received sterile water and supplement calcium (calcium L-lactate hydrate). After the hatchlings hatched, the size of the hatchlings in ovo was compared to the cultured hatchlings. After euthanasia, Dunn also recorded the wet mass for each hatchling and the length of the right third toe.

Dunn found that while there was an increase in the hatch rate of the embryos with the supplemental calcium, there was not a notable effect on the hatching mass of the chicks. Dunn also found that the chick embryos that were not supplemented with calcium did not hatch. From this, Dunn concluded that by having extra calcium added during the incubation period of chick embryos in shell-less culture systems, the rate of successful hatchings will increase without negatively impacting the growth and development of the chicks. Dunn’s research shows us how adaptable a developing baby chick is and that the eggshell and eggshell membranes that typically surround the egg are able to be replaced by a kitchen plastic wrap (F.O.R. wrap).

In conclusion, Dunn and his team found that the mass of the cultured hatchlings and the length of the right toe were notably less than the hatchlings in ovo. Most cultures that failed to hatch were due to the inability to properly absorb albumen. Dunn’s research is important because it provides us with a distinctive approach to studying the developing embryo's physiology, which can lead us to improved efficiency of incubation techniques. When chicks are raised in the eggshell, ~75% of the calcium comes from the eggshell in newly hatched chicks, this is why Dunn’s study is important because it

provides us with a method to investigate calcium metabolism in developing chicks. The study is also important because due to the easy access and rapid development of chicken embryos, we are able to learn more about the pathology and physiology of this species and it provides us with a model for developmental biology research which can ultimately extend into human research. If things like calcium and kitchen wrap are capable of creating a new way to develop baby chicks, what other everyday items could change the developmental process of other species?

Dunn, B. (2023). Supplemental calcium increases hatch rate but not hatchling mass of chick embryos in shell-less culture. Journal of Experimental Zoology Part A: Ecological and Integrative Physiology . 1– 12. https://doi.org/10.1002/jez.2678