{"id":743,"date":"2020-03-18T20:45:57","date_gmt":"2020-03-18T19:45:57","guid":{"rendered":"https:\/\/cimafoundation.org\/2020\/03\/19\/nucleic-acids-and-cetacean-health\/"},"modified":"2022-09-29T08:19:01","modified_gmt":"2022-09-29T08:19:01","slug":"nucleic-acids-and-cetacean-health","status":"publish","type":"post","link":"https:\/\/www.cimafoundation.org\/en\/news\/nucleic-acids-and-cetacean-health\/","title":{"rendered":"Nucleic acids and cetacean health"},"content":{"rendered":"\n

A study just published in \u201cScientific Reports\u201d shows how the analysis of the ratio between nucleic acids can be a valid indicator of the health status of cetaceans, providing an approach for the study of these populations in the natural environment<\/em><\/h4>\n\n\n\n

To determine a whale or dolphin\u2019s state of health, let’s consider looking at its genetic material. Or rather, looking at the ratio between the two nucleic acids involved in protein synthesis, RNA and DNA. This is the finding suggested in a study<\/a> recently published in Scientific Reports<\/em>, signed by a group of Portuguese and one of our researchers.<\/p>\n\n\n\n

Nucleic acids as indicators of health status<\/h4>\n\n\n\n

Using genetic material to understand the\neco-physiological conditions of an animal has the advantage of requiring only a\nsmall sample of skin (especially notable given the particularly complex nature\nof research in marine environments) from which to extract nucleic acids. Genetic\nmaterial can provide important information. In fact, if the DNA content of\ncells is mostly constant during the life of an individual, the RNA, the\nmaterial on which protein synthesis is based varies instead according to growth\nneeds. In other words: the more an organism grows, the more it needs proteins\nto build and repair tissues, and consequently, the more it produces RNA.<\/p>\n\n\n\n

As a result, the relationship between RNA and cellular DNA provides clues about protein reserves, which in turn vary depending on the environmental <\/strong>conditions in which an organism lives, such as the availability of food.<\/p>\n\n\n\n

\u201cThis approach has so far only been applied to certain groups of animals\u201d, says Massimiliano Rosso, a researcher of the Marine Ecosystems Department<\/a> at CIMA Research Foundation and co-author of the study. \u201cIn the work just published, we tried to understand if it was also applicable to two species of cetaceans that, as apical predators, play a key role for the ecosystems in which they live. On the other hand, cetaceans are deeply influenced by anthropic pressure, for example due to habitat loss and pollution\u201d.<\/p>\n\n\n\n

Two species, two questions<\/h4>\n\n\n\n

The two species analyzed are the bottlenose dolphin (Tursiops truncatus<\/em>) and the Gray’s blackfish (Globichephala macrorhyncus<\/em>). Although both are classified as least concern by the IUCN, information on population trends is lacking. They are considered common in the Macaronesia area (the archipelagos of the North Atlantic and off the African coast), where they have been studied with genetic tests and photo-identification techniques. Yet we still know little about their health state<\/strong>, so they are good candidates for testing how the analysis of the relationship between nucleic acids can help obtain information about their physical condition.<\/p>\n\n\n\n

In particular, researchers have tried to answer two\nquestions. First, are there differences between the two species in terms of\nhealth and nutritional status? Secondly, are there differences within the same\nspecies, for example, due to sex or season?<\/p>\n\n\n\n

Healthy populations<\/h4>\n\n\n\n

In response, researchers conducting the study analyzed the ratio between RNA and DNA from samples of 39 bottlenose dolphins and 37 blackfishes collected during sea campaigns conducted between 2017 and 2018. The results of the analysis showed that the populations could be considered healthy, i.e. with a high ratio between the two nucleic acids. However, animals that are sedentary, i.e. do not move much from the island, would appear to have a more compromised health status<\/strong> than nomadic animals. In fact, the best results belong to some specimens of blackfish that have visited the waters around Madeira for some time, coming from unknown areas of the Atlantic Ocean. These individuals have been nicknamed “visitors”:<\/p>\n\n\n\n

 \u201cThe visitors\nseem to be in better nutritional condition. The hypothesis is that these\nanimals, given their more nomadic habits, are better able to adapt to the\ndifferent oceanic environments and therefore to nourish themselves more\nefficiently. More studies will be necessary, however, to confirm this,\u201d explains\nRosso.<\/p>\n\n\n\n

In terms of intraspecific differences, researchers\nfound no significant differences between the sexes. This is interesting because\nthe difference between the sexes was observed in studies previously conducted on\nother groups of animals. \u201cNot finding gender differences is counterfactual. While\nour results did not show this difference, again, further research is needed to\nconfirm the result\u201d, the researcher adds.<\/p>\n\n\n\n

Finally, in general, bottlenose dolphins showed a higher\nRNA\/DNA ratio than blackfish. However, this may not be due to a better health\nstatus, but to an intrinsic species-specific difference.<\/p>\n\n\n\n

Towards future studies<\/h4>\n\n\n\n

Although the work highlights the applicability of the\nstudy of nucleic acids to assess the health status of cetacean populations, the\nauthors point out some limitations of this approach. For example, they note\nthat it is difficult to combine results with morphometric tests because\ncetaceans move rapidly, which does not allow for precise measurements. In\naddition, different tissues may have different RNA to DNA ratios, so it is very\nimportant to be sure to always have samples from the same part of the animal’s\nbody. Despite this, the results are encouraging.<\/p>\n\n\n\n

\u201cThis work is the first to apply the analysis of the\nrelationship between nucleic acids to these large marine predators in order to\nstudy their ecophysiological state. It is for this reason that many of the\nresults we have obtained will need to be confirmed and further analyzed in the\nfuture,\u201d concludes Rosso. \u201cAt the same time, we have shown how this approach\ncan be a valuable study tool for animals on which research is traditionally\ndifficult.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"

A study just published in \u201cScientific Reports\u201d shows how the analysis of the ratio between nucleic acids can be a valid indicator of the health status of cetaceans, providing an approach for the study of these populations in the natural environment To determine a whale or dolphin\u2019s state of health, let’s consider looking at its […]<\/p>\n","protected":false},"author":1,"featured_media":747,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[121,12],"tags":[84],"class_list":["post-743","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-marine-ecosystems","category-uncategorized","tag-data"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.cimafoundation.org\/en\/wp-json\/wp\/v2\/posts\/743","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.cimafoundation.org\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.cimafoundation.org\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.cimafoundation.org\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.cimafoundation.org\/en\/wp-json\/wp\/v2\/comments?post=743"}],"version-history":[{"count":0,"href":"https:\/\/www.cimafoundation.org\/en\/wp-json\/wp\/v2\/posts\/743\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.cimafoundation.org\/en\/wp-json\/wp\/v2\/media\/747"}],"wp:attachment":[{"href":"https:\/\/www.cimafoundation.org\/en\/wp-json\/wp\/v2\/media?parent=743"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.cimafoundation.org\/en\/wp-json\/wp\/v2\/categories?post=743"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.cimafoundation.org\/en\/wp-json\/wp\/v2\/tags?post=743"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}