To Each Mammal, Its Milk

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1200px)" type="image/jpeg"/> <source srcset="/web/20211231072145im_/https://www.nist.gov/sites/default/files/styles/1200w_x_600h/public/images/2021/01/14/NIST_MilkCollectionAtTheZoo_wide.JPG?itok=yihOmdvr 1x, /web/20211231072145im_/https://www.nist.gov/sites/default/files/styles/2400w_x_1200h/public/images/2021/01/14/NIST_MilkCollectionAtTheZoo_wide.JPG?itok=5-EnktLC 2x" media="(min-width: 800px)" type="image/jpeg"/> <source srcset="/web/20211231072145im_/https://www.nist.gov/sites/default/files/styles/800w_x_400h/public/images/2021/01/14/NIST_MilkCollectionAtTheZoo_wide.JPG?itok=QWRSI5Nj 1x, /web/20211231072145im_/https://www.nist.gov/sites/default/files/styles/1600w_x_800h/public/images/2021/01/14/NIST_MilkCollectionAtTheZoo_wide.JPG?itok=_Y46E0kg 2x" media="(min-width: 640px)" type="image/jpeg"/> <source srcset="/web/20211231072145im_/https://www.nist.gov/sites/default/files/styles/640w_x_320h/public/images/2021/01/14/NIST_MilkCollectionAtTheZoo_wide.JPG?itok=89B9OkG3 1x, /web/20211231072145im_/https://www.nist.gov/sites/default/files/styles/1280w_x_640h/public/images/2021/01/14/NIST_MilkCollectionAtTheZoo_wide.JPG?itok=n0h97BXU 2x" media="(min-width: 0px)" type="image/jpeg"/> <img src="/web/20211231072145im_/https://www.nist.gov/sites/default/files/styles/1200w_x_600h/public/images/2021/01/14/NIST_MilkCollectionAtTheZoo_wide.JPG?itok=yihOmdvr" alt="Two orangutans cling to a wire cage" title="Orangutan milk collection at the zoo" typeof="foaf:Image"/> </picture> <div class="nist-image__credit nist-content-row--caption" <span class="nist-image__credit-label">Credit: </span>R. Press/NIST </div> </div> </div> <div class="nist-block nist-block--no-margin"> <h1 class="text-center">To Each Mammal, Its Milk</h1> </div> <div class="nist-block nist-block--no-margin"> <div class="text-center"><span class="text-center text-bold">By: </span><a href="/web/20211231072145/https://www.nist.gov/people/rich-press" hreflang="en">Rich Press</a></div> </div> <div class="nist-block nist-block--no-margin margin-y-205"> <div class="text-center font-body-md"><time datetime="2019-05-07T12:00:00Z">May 7, 2019</time> </div> </div> <div class="nist-block">  <div class="text-center"> <a target="_blank" href="https://web.archive.org/web/20211231072145/https://www.facebook.com/share.php?u=https://www.nist.gov/feature-stories/each-mammal-its-milk" title="Facebook" class="nist-social nist-social--facebook float-none"> <span>Facebook</span> </a> <a target="_blank" href="https://web.archive.org/web/20211231072145/https://www.linkedin.com/shareArticle?mini=true&url=https://www.nist.gov/feature-stories/each-mammal-its-milk&source=https://www.nist.gov/feature-stories/each-mammal-its-milk" title="Linkedin" class="nist-social nist-social--linkedin float-none"> <span>Linkedin</span> </a> <a target="_blank" href="https://web.archive.org/web/20211231072145/https://twitter.com/intent/tweet?url=https://www.nist.gov/feature-stories/each-mammal-its-milk&status=https://www.nist.gov/feature-stories/each-mammal-its-milk" title="Twitter" class="nist-social nist-social--twitter float-none"> <span>Twitter</span> </a> <a href="https://web.archive.org/web/20211231072145/mailto:/?subject=NIST.gov&body=Check out this site https://www.nist.gov/feature-stories/each-mammal-its-milk" title="Email" class="nist-social nist-social--envelope float-none"> <span>Email</span> </a> </div>  </div> <div class="nist-block"> <div class="bg-base-lighter nist-content-row nist-content-row--width-normal nist-content-row--bg paragraph paragraph--type--text-bg-color paragraph--view-mode--default"> <div class="nist-content-row__inner"> <div class="text-long"> <p>Milk — it’s what distinguishes mammals from the rest of the animal kingdom. It’s also an incredibly complex substance, and scientists are still working to identify the many chemical components of milk and the roles they play in nutrition, immunity, brain development and other areas. As part of this effort, researchers at the National Institute of Standards and Technology (NIST) and the Smithsonian’s <a href="https://web.archive.org/web/20211231072145/https://nationalzoo.si.edu/">National Zoo and Conservation Biology Institute</a> are studying the unique milks of many species. In a related project, NIST scientists are also studying the composition of human milk. This research will help zoos raise healthy animals and help scientists understand how mother’s milk promotes the development of healthy human babies. </p> <p> </p> <figure class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/05/06/nist_orangutan_01.jpg?itok=Na7OziOx" data-media-id="524066"><img alt="A baby orangutan sits atop her mother's shoulders. " height="960" loading="lazy" src="/web/20211231072145im_/https://www.nist.gov/sites/default/files/styles/960_x_960_limit/public/images/2019/05/06/nist_orangutan_01.jpg?itok=2YjcPKep" typeof="foaf:Image" width="640"><figcaption class="nist-image__caption"><div class="nist-image__caption-content" data-caption-editable="true"> </div> <div class="nist-image__credit"> <span class="nist-image__credit-label">Credit:</span> R. Press/NIST </div> </figcaption></figure><p>Batang, a Bornean orangutan, and her two-year-old, Redd, live at the National Zoo in Washington, D.C. </p> <p> </p> <figure class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/05/06/nist_orangutan_02.jpg?itok=GsjYd5Z-" data-media-id="524071"><img alt="An orangutan allows a worker to collect her breast milk into a vial" height="3459" loading="lazy" src="/web/20211231072145im_/https://www.nist.gov/sites/default/files/images/2019/05/06/nist_orangutan_02.jpg" typeof="foaf:Image" width="5188"><figcaption class="nist-image__caption"><div class="nist-image__caption-content" data-caption-editable="true"> </div> <div class="nist-image__credit"> <span class="nist-image__credit-label">Credit:</span> R. Press/NIST </div> </figcaption></figure><p>Every week, primate keeper Erin Stromberg collects milk from Batang. Scientists analyze those milk samples to track how the milk’s nutritional profile changes as the infant gets older. That way, if any zoo has to create a milk substitute for a young orangutan, they can make a formula appropriate for the youngster’s age.</p> <p> </p> <figure class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/05/06/nist_orangutan_03.jpg?itok=WKHUUyTa" data-media-id="524076"><img alt="Zookepper gives a peanut to an orangutan" height="3744" loading="lazy" src="/web/20211231072145im_/https://www.nist.gov/sites/default/files/images/2019/05/06/nist_orangutan_03.jpg" typeof="foaf:Image" width="5616"><figcaption class="nist-image__caption"><div class="nist-image__caption-content" data-caption-editable="true"> </div> <div class="nist-image__credit"> <span class="nist-image__credit-label">Credit:</span> R. Press/NIST </div> </figcaption></figure><p>Batang has been trained to give milk voluntarily and is rewarded with peanuts for doing so. She can walk away at any point and is never forced to participate. Stromberg is the only keeper who collects milk from Batang, and over time they’ve developed a close relationship. “She’s smart as a whip, and she has a very strong personality,” Stromberg said.</p> <p> </p> <figure class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/05/06/nist_orangutan_04.jpg?itok=cx5TiJxw" data-media-id="524081"><img alt="hand holding a vial filled with breast milk " height="3744" loading="lazy" src="/web/20211231072145im_/https://www.nist.gov/sites/default/files/images/2019/05/06/nist_orangutan_04.jpg" typeof="foaf:Image" width="5616"><figcaption class="nist-image__caption"><div class="nist-image__caption-content" data-caption-editable="true"> </div> <div class="nist-image__credit"> <span class="nist-image__credit-label">Credit:</span> R. Press/NIST </div> </figcaption></figure><p>Stromberg only needs to collect a small amount of milk from Batang. The milk in this vial is more than enough for chemists to analyze in the lab. </p> <p> </p> <figure class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/05/06/nist_orangutan_05.jpg?itok=5plJpByL" data-media-id="524086"><img alt="close up of an orangutan getting a peanut" height="3164" loading="lazy" src="/web/20211231072145im_/https://www.nist.gov/sites/default/files/images/2019/05/06/nist_orangutan_05.jpg" typeof="foaf:Image" width="4746"><figcaption class="nist-image__caption"><div class="nist-image__caption-content" data-caption-editable="true"> </div> <div class="nist-image__credit"> <span class="nist-image__credit-label">Credit:</span> R. Press/NIST </div> </figcaption></figure><p>Redd gets to enjoy a few peanuts when his mom is giving milk. Like wild orangutans, he will nurse until he’s 6 or 7 years old. This makes orangutans the longest nursing of all mammal species. Bornean orangutans are one of three species of orangutans, all of which are <a href="https://web.archive.org/web/20211231072145/https://www.iucnredlist.org/species/17975/123809220">critically endangered</a>.</p> <p> </p> <figure class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/05/06/nist_nationalzoomilkrepository_01.jpg?itok=UujmjrIK" data-media-id="524021"><img alt="A man and a woman stand outside a freezer. The man is holding out a milk sample in a tube." height="3744" loading="lazy" src="/web/20211231072145im_/https://www.nist.gov/sites/default/files/images/2019/05/06/nist_nationalzoomilkrepository_01.jpg" typeof="foaf:Image" width="5616"><figcaption class="nist-image__caption"><div class="nist-image__caption-content" data-caption-editable="true"> </div> <div class="nist-image__credit"> <span class="nist-image__credit-label">Credit:</span> R. Press/NIST </div> </figcaption></figure><p>NIST research chemist Connie Remoroza meets with Michael Power, the Smithsonian scientist who curates the zoo’s milk repository. Remoroza is part of a NIST research team that uses advanced instruments to identify chemical compounds and determine their molecular structure. They are working with Smithsonian scientists to conduct specialized analysis of milk from several species.</p> <p> </p> <figure class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/05/06/nist_nationalzoomilkrepository_02.jpg?itok=b_4rIveo" data-media-id="524091"><img alt="Close up of vials of lion's milk" height="3744" loading="lazy" src="/web/20211231072145im_/https://www.nist.gov/sites/default/files/images/2019/05/06/nist_nationalzoomilkrepository_02.jpg" typeof="foaf:Image" width="5616"><figcaption class="nist-image__caption"><div class="nist-image__caption-content" data-caption-editable="true"> </div> <div class="nist-image__credit"> <span class="nist-image__credit-label">Credit:</span> R. Press/NIST </div> </figcaption></figure><p>Michael Power retrieves a sample of African Lion’s milk from a freezer. Remoroza will bring the sample back to the lab at NIST, where she will identify the multitude of complex sugars, called oligosaccharides, present in the milk. These sugars have a more complicated molecular structure than the simple sugars found in most foods, and they do more than provide calories. Some play a role in immunity while others promote brain development.</p> <p> </p> <figure class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/05/06/nist_nationalzoomilkrepository_03.jpg?itok=b18o6mvV" data-media-id="524096"><img alt="close up of vial of lion's milk" height="3744" loading="lazy" src="/web/20211231072145im_/https://www.nist.gov/sites/default/files/images/2019/05/06/nist_nationalzoomilkrepository_03.jpg" typeof="foaf:Image" width="5616"><figcaption class="nist-image__caption"><div class="nist-image__caption-content" data-caption-editable="true"> </div> <div class="nist-image__credit"> <span class="nist-image__credit-label">Credit:</span> R. Press/NIST </div> </figcaption></figure><p>This sample of African Lion’s milk was collected from an animal in the wild. How does one collect milk from a lion? Wildlife biologists collected this sample after sedating the animal to conduct a health checkup and gather scientific data. Biologists from around the world send milk samples to Power for inclusion in the zoo’s collection.</p> <p> </p> <figure class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/05/06/nist_nationalzoomilkrepository_05.jpg?itok=96Fd9do7" data-media-id="524101"><img alt="Man stands in front of a freezer holding a stack of milk vials. NIST scientist stands next to him." height="3744" loading="lazy" src="/web/20211231072145im_/https://www.nist.gov/sites/default/files/images/2019/05/06/nist_nationalzoomilkrepository_05.jpg" typeof="foaf:Image" width="5616"><figcaption class="nist-image__caption"><div class="nist-image__caption-content" data-caption-editable="true"> </div> <div class="nist-image__credit"> <span class="nist-image__credit-label">Credit:</span> R. Press/NIST </div> </figcaption></figure><p>Zoo scientist Michael Jakubasz hauls samples out of the deep freeze, where they are kept for long-term storage.</p> <p> </p> <figure class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/05/06/nist_nationalzoomilkrepository_07.jpg?itok=UvyAo716" data-media-id="524106"><img alt="A hand reaches into a freezer filled with milk" height="3744" loading="lazy" src="/web/20211231072145im_/https://www.nist.gov/sites/default/files/images/2019/05/06/nist_nationalzoomilkrepository_07.jpg" typeof="foaf:Image" width="5616"><figcaption class="nist-image__caption"><div class="nist-image__caption-content" data-caption-editable="true"> </div> <div class="nist-image__credit"> <span class="nist-image__credit-label">Credit:</span> R. Press/NIST </div> </figcaption></figure><p>Milk samples at the National Zoo’s milk repository are stored at -80C.</p> <p> </p> <figure class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/05/06/nist_nationalzoomilkrepository_06.jpg?itok=TANiUIQj" data-media-id="524111"><img alt="close up of containers filled with rhino milk" height="3744" loading="lazy" src="/web/20211231072145im_/https://www.nist.gov/sites/default/files/images/2019/05/06/nist_nationalzoomilkrepository_06.jpg" typeof="foaf:Image" width="5616"><figcaption class="nist-image__caption"><div class="nist-image__caption-content" data-caption-editable="true"> </div> <div class="nist-image__credit"> <span class="nist-image__credit-label">Credit:</span> R. Press/NIST </div> </figcaption></figure><p>In addition to the samples of Rhinoceros milk shown here, the milk repository includes some 15,000 samples from more than 200 species. Smithsonian scientists analyze these samples to determine how much sugar, fat and protein they contain, among other things. Milks vary greatly between species, and any zoo can use this information to formulate a species-specific milk substitute if one of their animals is unable to nurse her young.</p> <p> </p> <figure class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/05/06/nist_chemicalanalysisofmilk_01.jpg?itok=CM0bP4w4" data-media-id="524116"><img alt="close up of a hand pushing milk into a vial" height="3744" loading="lazy" src="/web/20211231072145im_/https://www.nist.gov/sites/default/files/images/2019/05/06/nist_chemicalanalysisofmilk_01.jpg" typeof="foaf:Image" width="5616"><figcaption class="nist-image__caption"><div class="nist-image__caption-content" data-caption-editable="true"> </div> <div class="nist-image__credit"> <span class="nist-image__credit-label">Credit:</span> R. Press/NIST </div> </figcaption></figure><p>At the lab, Remoroza prepares a sample of human milk for analysis. So far, she and her colleagues have documented 74 different oligosaccharides in human milk, including 12 that were not previously known to be there. This information can be useful when formulating milk substitutes and when researching the myriad ways in which milk promotes healthy development.</p> <p> </p> <figure class="align-center nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2019/05/07/nist_chemicalanalysisofmilk_05.jpg?itok=yEMfvGdg" data-media-id="524121"><img alt="woman stands at mass spectrometer machine" height="3744" loading="lazy" src="/web/20211231072145im_/https://www.nist.gov/sites/default/files/images/2019/05/07/nist_chemicalanalysisofmilk_05.jpg" typeof="foaf:Image" width="5616"><figcaption class="nist-image__caption"><div class="nist-image__caption-content" data-caption-editable="true"> </div> <div class="nist-image__credit"> <span class="nist-image__credit-label">Credit:</span> R. Press/NIST </div> </figcaption></figure><p>Remoroza operates a mass spectrometer, a laboratory instrument used to identify chemical compounds. “We want to find out as many details as we can about milk because it is so important, but so little is known about its chemistry,” Remoroza said.</p> </div> </div> </div> <div class="bg-primary-lighter nist-content-row nist-content-row--width-normal nist-content-row--bg paragraph paragraph--type--text-bg-color paragraph--view-mode--default"> <div class="nist-content-row__inner"> <div class="text-long"> <h3>For more information about Remoroza’s research, check out "<a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="8369fb41-e119-4a65-bd5d-fe989a05e0a9" href="/web/20211231072145/https://www.nist.gov/news-events/news/2019/05/how-milk-does-animal-body-good" title="How Milk Does an Animal Body Good">How Milk Does an Animal Body Good</a>."</h3> </div> </div> </div> </div> <div class="nist-block nist-content-row--footer">  <div class="nist-tags"> <a href="/web/20211231072145/https://www.nist.gov/topic-terms/glycomics" hreflang="en">Glycomics</a>, <a href="/web/20211231072145/https://www.nist.gov/topic-terms/chemistry" hreflang="en">Chemistry</a> and <a href="/web/20211231072145/https://www.nist.gov/topic-terms/analytical-chemistry" hreflang="en">Analytical chemistry</a></div>  </div> <div class="nist-block">  <div class="text-center"> <a target="_blank" href="https://web.archive.org/web/20211231072145/https://www.facebook.com/share.php?u=https://www.nist.gov/feature-stories/each-mammal-its-milk" title="Facebook" class="nist-social nist-social--facebook float-none"> <span>Facebook</span> </a> <a target="_blank" href="https://web.archive.org/web/20211231072145/https://www.linkedin.com/shareArticle?mini=true&url=https://www.nist.gov/feature-stories/each-mammal-its-milk&source=https://www.nist.gov/feature-stories/each-mammal-its-milk" title="Linkedin" class="nist-social nist-social--linkedin float-none"> 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To Each Mammal, Its Milk | NIST