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Key Note Lecture: The Evolution of Lactation in Mammalian Species
Olav T. Oftedal
Monday, Sept. 23, 2019 · 9:29 a.m. · 01h 00m 54s
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integration to grammar is very good we're uh what is known now
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uh about the relationship between a male and a or a unity
00:00:13
uh my work was done some years ago on and
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it has a long term scheme of the evolution of lactation
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uh uh i could say among the million species
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of course we know there is great diversity in the
00:00:33
lactation among mammals there's great diversity in the composition of no
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there's great diversity in the length of lactation there's great
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diversity in the degree to which mothers use the troll reserves
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uh there's great diversity with regard to the size of weaning uh at the end of lactation
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and there are many social aspects that inter relate with lactation
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for example i just sort of put together a table which has a or categories of knock fat
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and you can see that on the far left hand side
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are there are very low fat jokes which include human no
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on the far right side they're very high fat dogs which includes some of the seal no
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but the point is that the even though there's may species or cluster down near the lower
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fat content there also are many species uh not just the seals that have high fat no
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i get a work early on on uh in the eighties on a
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black bears a because i was very interested in this species in terms of
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the uh offspring are a born in and again
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uh the mothers give person middle of january the top photo on the left shows
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someone uh putting a hole in with a drug to map remote allies the female there
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uh and uh the the uh we uh warren nitrogen
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cycles from other to cops uh during the lactation period
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it's actually a a phenomenal of a system in which uh the mother is in the den
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just lack taping she's provide actually six a consuming mix creator of the young
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um but she's not eating or drinking herself otherwise for months
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where we uh we and if we look at the uh black pair caught the
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different ages uh going from newborn do one month or two months or three months
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you'll see they change a lot inside but they're all dependent on now
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uh and they all actually have very different
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a lactation dependencies based on uh the mothers activity
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the cops are very on a poorly developed our outer shell at birth
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a switch from a plus central look goes and amino
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acids to milk fat and protein uh when they're born
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uh the milk it's mostly logan carbohydrate it's mostly like a sack right
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we've had a lot of work done on this in the last twenty years
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uh and then go crack increases the milk is low in protein
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all these things we could discuss in detail with regard to this species
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and had this species has evolved or a lactation strategy of its own
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uh logo healed uh and reduce the glucose demand on the fasting mother
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so there is species has different lactation strategies
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uh we worked on california see lines which you can see the upper photo is
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uh agreeing beach you you can see all the animals
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that have accumulated there the mothers come ashore and give birth
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so we end up with a basically a a riot of parts on the beach uh mon mom's coming ashore trying to
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find them uh and then after nursing going out to see
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if he did for several days um so the uh uh
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forging trips of the mother are important not just because she's acquiring
00:04:45
you treat yourself but the pops are fasting which is gone so they have an interim
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intermittent fasting approach which again is different from what you would think of for many species
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uh and the mother's return uh to nurse their pop for about one
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half days at a time and this continues for eleven months and this species
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so the milk intake is intermittent that is moderately high there's no
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lactose in the milk and there's no lactose base to look exactly right
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uh there is uh some reason uh do you relate that
00:05:25
to their period of going to see and maintaining lactation at sea
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uh the nokia intake during the nursing periods uh is about thirty percent of pop
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body mass uh but again there's intermittent fast so
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the popular only consuming a small now on average
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and again what is this due to the microphone
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um
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and again sends the parts are very active in how high note about expenditure they're
00:05:57
very inefficient in growth in other words they have to have a lot of no energy
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uh and protein to grow and it you can see in the left
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hand graph that these are male and female pop that only about sixteen percent
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oh it doesn't matter what about sixty percent a deposition
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so see lines and first years as a group of animals uh produce high
00:06:25
fat milk that reduces the they'll come volume that they have just agree at sea
00:06:31
and enables rapid energy transfer to the part when they come ashore
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knock secretion itself has been shown to be up and
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down regulated uh when the mothers ish ashore and se
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uh and the forging trips of the mothers in some species are two to three weeks
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now what that means is that hops are left on the shore to fast for two to three weeks
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uh so again i rather remarkable lactation strategy
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uh the consequence of which we don't fully understand
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uh and it's believed that the loss of alpha lack albumin
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is related to uh the ability for these emails to sustain lactation
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another species that i worked out or what it seals which give birth oh to well developed
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pops on unstable pack ice off the coast of in our case off the coast of canada
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um and the picture to lower right shows the ice flow and shows our research vessel
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uh obviously i i mention this because this is one of the species
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that's considered very susceptible to climate change because they are dependent on having
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ice uh that is rafting ice for the mothers to give birth to their pops
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on uh and they uh have to have a we are very tight time frame
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uh this is a species with a very short an intensive lactation
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so unlike the fur seals and see what you might think all seals
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are similar but these are are the uh numbers are the true still family
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uh and we demonstrated for the first time
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that the lactation duration is four days or less
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uh and uh that there's frequent nursing an mass
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gain of the pop of about seven kilograms per day
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uh which you when i first presented this data to some pediatricians i could not believe
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how could an animal absorbed that amount of facts in a day
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the milk is probably more aptly called heavy cream uh because
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you can see that it is a fifty six percent sixty
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one percent sixty one percent that's three sort of it's quote
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unquote stages of lactation which is zero two and four days
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uh and uh there's a picture is the one for me to just talk a little bit about
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the males and uh have a a platter they blow out their nose and they shake it up and
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down to i guess scare off other males and to attract females and make sure about ringing sound as they
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do this uh this uh particular photograph shows of email with the dark enter but
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uh because we were the process of collecting nope rubber and then we had this disturbance them because i don't stop everything and take pictures
00:09:49
and the shows that uh they manage shake
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strain efficiency uh in deposition uh the uh
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uh fat transfer from the do the pop
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uh is to possible about eighty eight percent rate
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um so it's obviously that the and this is a a four they'll
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pop on the right side in in the photograph you can see that he's
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rubies um in fact at this age they can't swim they can just float like a cork
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uh in the water um so it's it's actually with the with
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they do is they're getting under the ice nanny ices caring themself
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um so if they didn't have ice they couldn't swim that
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couldn't feed uh and it would be devastating for the species
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um and it's an extreme example of memory leopard secretions so i wanted to just show you
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some examples of a a very big difference
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is a month different species of wild that memphis
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and i worked on about seventy five species so i know they're very diverse
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uh but the bigger story as how lactation came to be and that's what the rest of my discussion will be on
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lactation uh it is a a defining characteristic of
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mammals in fact we're mammal come from and me
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uh and it was with the way in which uh
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they relies that lactation was what link all mammals together um
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they're uh can be a long a dependence uh and relate function which are you the um
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uh which is important in many different species whether you're talking about
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primates were the mothers are holding the inference or whether you're talking about
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animals are using nests um there is a a transfer
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of possible transfer of nutrients from one time and place
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uh to another time and place like some of our seals were going off a great distance there
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i didn't mention but some of the seals or swimming about of thousand
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kilometres to go get to forging sites and come back to that but
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obviously that's only possible uh if you have some
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way of of storing nutrients in transferring them which nokia's
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and you know how to such a radical uh
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uh approach especially compared to the preexisting kayaks are evil
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i don't need to elaborate on the fact that there are many novel aspects of lactation
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they're novel feeding types being based on its integration
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there's a novel gland type there's novel constituents in mail
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uh which channel functions there's novel degree of up regulation of secretion
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a novel degrees of the new nail immaturity which are dependent on on bill can lactation
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uh and novel the just of features onion h. how could such
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complex novelty right this was originally rages a challenge to the theory of
00:13:11
of natural selection uh and or when it ended up having to put together a
00:13:17
a chapter in his origin of species to try and respond how it
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was possible that you could have all of these things have evolved at once
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and again as i mentioned before there's many novel constituents i'm not gonna go
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into them in great detail but obviously there are things which are unique to milk
00:13:47
that are not find outside of male and then or genetic products of the mammary gland
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uh including an elf lacked albumin be elected logon way acidic protein in some species
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like lactation protein in some species and it's uh
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so there is some and the case scenes of course
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and some of the milk fat claudio membrane proteins that are all uh indicate
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a long period of of uh evolution and the evolution of many different constituents
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there has been your evidence uh that
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which i will briefly allude to a on a molecular evolution evolution of signal constituents
00:14:36
uh looking at the evolution uh of the development of
00:14:41
the mammary gland um which again shows a very interesting
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parallels across texas a and poorly apology which i will
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just show you a few pictures rather than going into detail
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um but obviously uh i believe that uh that evolution lactation has a
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very big part to play in yellow into logical history uh of the
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mammals that rose
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so if your questions uh how and when did member secretion a region a was
00:15:18
it before or after the origin of mammals we'll take that often we think of
00:15:24
lactation and mammals we don't relies it may be that you are the same
00:15:29
uh what evolution changes have occurred in male and what role
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the lactation play in the evolution mammals all again or actually
00:15:40
option of themselves and i'm just gonna go over them quickly
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but first we need to have an idea of what the time frame we're talking about is
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uh we are this is a model of the milky
00:15:53
way and that a line points to the location of or
00:15:59
a bar star of the sun and this whole thing is rotating
00:16:05
uh about every two hundred twenty million years
00:16:09
uh and so about three of these galactic
00:16:13
years before i either two or twenty years were the first multi each other animals animals
00:16:19
about you you get yours was the dollars dishes
00:16:25
that one and a half years the first sin apps it's these are the ancestors of mammals
00:16:32
and uh about one degree you're a complex lactation
00:16:37
table so there's been a long period of evolution
00:16:45
one of the most important initial evolutionary
00:16:49
steps was forming a skin that was like
00:16:53
the skin that would be important for the evolution of mammary glands uh and uh this was a a
00:17:00
qualified layer uh and a maturing a granular and
00:17:06
spires layers will refer to layer is a fraud scheme
00:17:11
the next step it is a truly glandular and take human where you have i guess a point
00:17:21
um where you you have a glance uh enlarge and in shutting down into the
00:17:28
skin on and in between them there or scales so this is a a a a
00:17:38
um this is an illustration of a a sicilian which
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is uh there are now known to be says humans which
00:17:45
produce a glandular skin they when the young are born the young scraped
00:17:52
the skin of the mother and get you change that nutrients from the mother
00:17:58
very similar to lactation in some ways but very dissimilar in other words
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uh this is a i want to sort of you a a bit of an overview of evolution
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i'm going back through time we have time on the
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left hand side to yell it so it all this time
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going up to younger time and then you have
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a long across of the top you have different groups
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uh that were involved in a mammalian evolution
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or are relative to the mail in evolution
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oh and basically there was the the so calls
00:18:41
an absence to form the ancestral room for mammals
00:18:45
split over in the corner force around three hundred million years ago from
00:18:51
the star opposite to produce all the reptiles and birds you
00:18:55
know which reptiles and birds so but also numbers or a long
00:19:00
a divergent a lineage uh and not very informative in terms of trying to understand
00:19:08
the evolution of like th uh in the middle of this thing there or you'll see
00:19:16
a little little bursts of blue lines which are just simply radiation so there's an absence
00:19:22
in each case that was radiation of the snatch it and then most of them
00:19:25
went extinct and if you remain the same issue the mail you forms at the end
00:19:31
the most the mixed think but if you remain in were in fact the ancestors of mammals
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um and the other other thing in here in the middle is used either or some
00:19:43
uh schematics of glance with with here are sticking out
00:19:47
i'll come back to these because this is a very interesting
00:19:51
a phenomenon uh is the structure of mammary glands in different groups of mammals
00:20:01
so this is this fundamental diversions that occurred around three million years ago
00:20:06
where the syrup says to ensure reptiles and birds separated from sin axes
00:20:12
their ancestral to to mammals uh and
00:20:16
had very different uh soft tissue characteristics
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um based on what we understand of uh the fossil
00:20:24
record uh and the ancestral of this you send in forms
00:20:33
oh here's another example of uh uh something that uh
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show the again showing from going from the left up
00:20:42
two words the right or the relations of different tack so
00:20:47
uh and again showing that they existed for certain periods of time then they went extinct and it was
00:20:52
only the mail informed actually led to the mail yeah
00:20:56
ah around a hundred and fifty a million years ago
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and then i you'll notice that the whole question where is
00:21:11
the origin of lactation in all these i mean all these radiation
00:21:28
well looking at the a a size a and e. asked me to a mass
00:21:36
of the um the million forms who became extremely small
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uh we have argued that they must have been lactic
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if you look at the photograph to the right uh i you'll notice there's a paper
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clip that's a paper clip for scale so that is the adult side of an adult female
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and it's of similar size to the smallest mammals the live today
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uh we believe that this was part and parcel of the transition
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um that led uh to the million lactation as we know it today
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so these try asking the mail it forms a were are very small and of the remote from
00:22:29
of us made from fossil evidence of unable to produce a lot of a four and other mickey on
00:22:37
so there for argue they had small legs with immature offspring
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and they're and they also had limited use replacement in other
00:22:46
words they lost the frequency of twos replacements are the young
00:22:51
couldn't eat solid foods uh and so all of us just the
00:22:56
most of black dated uh and so you know when we consider the
00:23:01
evolution of language proteins and sugars we have to go back uh
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a long period of time and not just to the beginning of mammals
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not molecular evolution of course there
00:23:29
is evidence of variation among species
00:23:34
uh and uh suggestions the the atlanta at a genetic
00:23:39
level that different compounds have a drive from earlier combo
00:23:45
um and you know and stickler there i will talk a bit about uh keychain my cells
00:23:51
um i will talk a bit about no fat glottal
00:23:54
numbering constituents that about alpha like the human like two sentences
00:23:59
a bit about elected lobby one and the bit about a ways to go to just down the road from some other tax
00:24:14
now i'm sure you will see a model of what the casing looks like how big it is
00:24:21
uh and uh how it is composed a variety of different
00:24:26
um uh types of casings uh that form
00:24:30
the structure a huge structure of including calcium advance
00:24:37
well a very uh
00:24:41
well that was speaking at a massive structure
00:24:45
and very important to be uh
00:24:50
transfer of protein from other young
00:24:54
and calcium voters
00:25:01
no this is just a a a graph showing the variety of genes that or
00:25:10
in similarity relationship to place in jeans uh
00:25:14
and studies it and uh done that suggests
00:25:18
the origin of the scenes from rule your
00:25:22
uh which a sector calcium binding foster proteins
00:25:28
oh and suggestion that uh they were involved in relation of
00:25:34
a minimisation uh and could even have been involved in regular the regular they
00:25:40
in and minerals ration of a a
00:25:49
of course we all know in this room that that uh
00:25:53
the uh
00:25:56
'kay scenes precipitate as per has come again
00:25:59
that this as important effect on the uh
00:26:07
on the the uh stomach environment uh and uh the way in which these
00:26:13
things or broken down ah can have effects on microbial communities uh and it
00:26:21
well so gradual release of protein and fat uh to
00:26:25
the intestines uh which is an important feature no digestion
00:26:33
of course lactose uh which is in los requires yes on black case
00:26:40
and so really we're dealing with a co evolution of multiple factors of uh of
00:26:49
like they said lack those case genes proteins fats
00:26:54
everything is in related in terms of their evolution
00:27:01
this is just a schematic uh of a
00:27:05
at a site or a secretary cell members actors all uh and on the right the
00:27:12
rich proteins that are involved in penetrating the um the uh
00:27:18
no effect on remembering a and it's a associating with underling what blair
00:27:32
one of the uh features of a male fast
00:27:36
sentences is the engine off of it levels of that
00:27:41
and one thing that occurred to me was that of course if you have
00:27:44
a high rate of no fat sentences you can't have a high rate of
00:27:50
signed up last night last with the i'm not fat o'clock bills because that would basically
00:27:59
uh undermine second or sell and so it seems this was a major and uh aspect of the
00:28:06
evolution of the uh no fact wobble was the
00:28:09
ability to minimise the cytoplasm it gets lost with the
00:28:16
no fact lotto
00:28:20
and that a a specific proteins have involved and
00:28:24
i'm not gonna talk about them any like here but
00:28:27
hell hole of the uh membrane tight to the uh
00:28:33
underline fat layer uh and that this is no doubt
00:28:37
part and parcel of there's a a mechanism of of
00:28:44
reducing a side of plastic lost during a press which
00:29:03
so when we talk about the evolution of a liberal secretion we have to think about all
00:29:08
the various constituents that go into each of the structures that are part and parcel of no
00:29:16
including uh the uh constituents the or involved in the hope that god will member
00:29:25
so it was a key step on in e. up regulation of
00:29:30
that secretion was minimising the amount of membrane inside unless the walls
00:29:42
course i should i should i should add here that
00:29:45
we don't really have much information on you know many speeches
00:29:52
uh for example we had these put seals that i told you that had this
00:29:57
tremendous manifests krishna we don't really know how they manage that how to accomplish that
00:30:03
and that's true of any number of different
00:30:06
living actually uh there are species specific solutions ah that have the bell
00:30:23
now of course we know the latter's is an
00:30:26
important constituent of cows milk and move your email is
00:30:31
um but it's a lot less up it's uh what a lot less uh
00:30:39
major in important then i realised when i first started working on on lactation
00:30:46
i'm lactose is not found elsewhere in nature it
00:30:49
requires a special modifier protein helpful act albumin allows
00:30:53
okay i'll do you want to add collectors to look at us and that's a unique to the memory
00:31:01
not no one else were per elsewhere in nature um but what just slide fails to recognise
00:31:09
lactose may or may not be the final step
00:31:18
it's thought that helpful act albumin uh is derived from uh
00:31:24
see lies design just and team microbial protein and ask integrations
00:31:30
oh and it's in fact true that there are multiple constituents are found in order of
00:31:35
ought to be related to the uh earlier
00:31:40
immune function uh in earlier in a evolution
00:31:47
and again the uh
00:31:50
uh mm long
00:31:52
red line really points to the separation of so rob
00:31:56
says and the and the sun actions as as the date
00:32:00
had previously been suggested uh based on a molecular studies
00:32:13
now obviously if you're going to have a lattice you
00:32:17
have have lactate but i think it's a silly right
00:32:23
a if people don't have who lactation parent at the black
00:32:28
puts same thing with california see why is if you give
00:32:32
lactose containing formula jewel california's you line you produce a violent die right
00:32:38
a very quickly uh and and that has been known for many years because it was so so ah yes
00:32:47
obviously we need to have both black case and a lactose if
00:32:52
we're gonna digest lactose we need and black case but that would mean
00:32:57
yeah we need to have evolution of lack case if we're going to have the evolution of
00:33:03
lectures and again so this is the interactions of
00:33:07
different constituents other important because of their in relationships
00:33:16
and then i guess the question was how did lactose involved in you know if if there was no lack taste and then the ending
00:33:23
and vice versa a hack subject anyway
00:33:28
you have to have the your lectures but no lactation got a
00:33:33
problem and and vice versa here lactation lattices doesn't do you much good
00:33:46
so among mammals uh we do know that there are species that do not have a lactate
00:33:53
probably cannot digest free lactose
00:33:56
um many of them however
00:34:00
a fairly high levels of a like a sack arrives in their mail
00:34:05
and that is perhaps been over over my cover the biggest change we've seen is this recognition
00:34:13
the tremendous diverse not just a new remote you invoke have a greater diversity
00:34:18
lucas accuracy any other mammalian no as far as we know
00:34:23
um and we've looked at uh at other primates as well um
00:34:28
but there's a lot more like a sack right some people recognise uh
00:34:32
i'd in my earlier slide i mentioned about bears having
00:34:38
a little zacharias and there are no uh and
00:34:41
they have long complex structures we don't really know oh
00:34:47
the function of the structure we do not know
00:34:52
and i asked the school to come up with answers
00:34:56
oh we don't know you know with a few conceal a like a sack
00:35:02
arise or style you're willing to sacrifice
00:35:05
what effect having having other being digested
00:35:10
um i thought many years ago that well of the the look of zacharias were
00:35:16
being uh taken up into the intersection broken down there but it now or no because
00:35:24
you know there's such a pretty diversity little zacharias so here we have basically a big one no
00:35:31
about human i mean well mailing lactation and lot papers coming out but
00:35:37
what what the significance of them biologically uh one gems
00:35:42
of a micro while it's it's not she served me um
00:35:49
and the uh for a c. lines in for seals uh have lost single
00:35:54
into secondarily lost it all has to synthesise lectures uh and cannot towering lattice informal
00:36:07
now we've recently been trying to look at some of the
00:36:12
problem quote a ancestral forms of mammals line
00:36:18
particular channels which are an egg line species
00:36:26
i'm okay
00:36:38
oh and have come to look at o. lactose set
00:36:44
as a uh
00:36:47
a substrate to which other constituents are added um because we see this in fact that there might
00:36:53
be a small amount of lactose and then a larger a number of compound sort of an added uh
00:37:01
and uh that uh uh the enzymes that were
00:37:06
involved in forming these are like a sack rides were
00:37:10
uh had have had already existing in had a many functions
00:37:19
we got a i was particularly interested in the whole idea of whether male does been
00:37:25
spin something i've talked about for some years uh whether male
00:37:29
could've evolving relationship daggers and providing a surface secretion to x.
00:37:36
uh and we do have compounds in a can
00:37:40
of milk a witch or a anti microbial in nature
00:37:46
um so they are obviously doing something and in fact the
00:37:52
brown insurers or four oh acid teal three prime slyly
00:37:57
lactose uh which is a a a restricts microbial metabolism
00:38:03
yeah if it's really complicated when you think about the fact that you can
00:38:08
uh gives birth and then he just the egg in a pouch uh and uh
00:38:15
then the there
00:38:19
lack taping or producing secretions which are being absorbed by the eighties
00:38:26
um because these ace actually today before they are lay
00:38:31
or uh uh uh apartment show type that swells with with fluid um
00:38:38
and so you know the question then we'll games could could it be
00:38:41
that this was an original function of like a sack races secondarily later on
00:38:48
became providing lactose
00:38:52
as a source of nutrients to click our group to
00:38:57
use the reasons um and again but that's just hypothetical
00:39:08
this is just a list o. of notes are highly exact right in little if any lactose
00:39:15
the uh came in the platypus or you know the primitive angling mammals
00:39:21
ah all known more soupy also sort of kangaroos
00:39:24
and their allies uh have no so highly exact right
00:39:29
all layers and true seals i've know
00:39:31
for high analogue zacharias many hardcore searches uh
00:39:36
skunks and nanking warnings and raccoons and cats um produced no that are high and
00:39:43
oh exact rhymes yeah i should point out that these are not all the same uh like a
00:39:48
sack right so that the exact right pattern in a spectrum will be different from that and make
00:39:55
um so we have this variation among species like in the pattern
00:40:01
of like the sacrifice a without really knowing what significance it's um
00:40:08
many primates have both lactose handling zacharias uh
00:40:13
and it's not clear why they're such diversity in the likes of exact rights
00:40:18
a moan mammalian mailbox um and uh it's it's a
00:40:23
slow and tedious process to add add species to the list
00:40:31
no um other other proteins uh are very interesting from the
00:40:36
point of view of it evolution below like eleven is of it
00:40:40
class of proteins known as a like okay link which haven't define structure and these have been
00:40:47
look at in terms of of their relationships to each other another
00:40:52
uh like okay islands and all get from that is that the
00:40:59
the electrical islands were one among the earliest diverging
00:41:04
uh like okay i once and native or apparently diversion earlier
00:41:09
than the other um yeah otherwise okay ones that are found in
00:41:15
in a fish have think it'll make sense uh it's so but the point
00:41:23
is that it each constituent in in no okay has potential significance in terms of
00:41:29
trying to understand but it's evolution and biological importance um
00:41:38
hum
00:41:48
and a way sick protein it again is another of protein and that is found
00:41:53
in road and and other no actually at the all evidence is that it was uh
00:41:58
quote unquote ancestral protein it's just been lost many mammals um
00:42:03
and that seems to be true of other uh no constituents
00:42:09
it is a a a ancient origin for this uh
00:42:14
for the self like or domains to define this group of
00:42:18
uh proteins um and uh they again seemed to be a a
00:42:25
related to the anti microbial and and probably ace inhibitors
00:42:30
uh and so they're very interesting and how we overlooked
00:42:35
well um because they are found in either dairy animals or were
00:42:40
humans lactation but that doesn't mean they might not
00:42:44
be a very valuable a constituent to look at uh
00:42:51
and i don't know but anything or things like that
00:42:58
oh last i wanna talk a little bit about what my uh a pet
00:43:01
stories uh which is about uh the evolution of the lambs in um mammals
00:43:08
uh of course uh this schematic on the right is showing the
00:43:14
here follicle and then associate with the hair follicle us a beige is clay and and a problem the land
00:43:21
uh and not associate with hair follicle a a happens what plant
00:43:26
um but from what developmental perspective or
00:43:33
remote a logic developmental perspective of the uh hair follicle spacious
00:43:39
plan a plan formant developmental unit p. h. p. s. u.
00:43:45
which when i first discovered i didn't quite understand the significance of this
00:43:50
um but i thought it was you know very interesting or when i'm trying to think of how
00:43:55
what did the mammary glands evolved from an in my earliest
00:43:59
days i thought they were derived from from a problem type clients
00:44:04
if
00:44:08
there's no doubt that mammary glands are one gland uh uh it's one thing
00:44:15
you have to worry about courses with every glance in different taxes be different
00:44:21
you know structures have something that involves separately from different origins
00:44:26
um but but based on histology alter structure secretary mechanisms biochemical pathways
00:44:33
the second for products mail and uh the importance of options ocean
00:44:37
from not injection um it is clear that they're all the same
00:44:43
mammary glands of the mammary gland goes back to a common origin
00:44:52
uh uh looking at some really weird remembering lance uh oh
00:44:57
this is a mammary gland which is to atlanta spend i sacked
00:45:02
it out but it consists of a hundred to two hundred lobbing rules
00:45:07
but each of which drains separately each of which empties into a
00:45:13
the infant did your mother hair follicle so they're all so there's memory errors
00:45:19
sticking out associated with with each logical and these memory here
00:45:26
are bigger than they hear versions rounding coverage so they are distinctive
00:45:33
um
00:45:41
i guess the only picture will focus on is the middle one here which
00:45:45
is a you can see the egg is in being held between someone's fingers
00:45:52
see the fingernail there so edition idea how large a
00:45:56
these or uh at hatching have small for the eggs or
00:46:02
um
00:46:04
it is actually quite interesting that in the earliest faces of me every development in
00:46:10
the hidden uh the mammary gland looks very much oh oh like a skin plan
00:46:17
oh
00:46:20
and then i've developed an proliferate into that into that
00:46:25
other substantial structure
00:46:28
um
00:46:30
and this is just a cross section of our clan that shows that are married here is
00:46:39
on the right hand side memory here are some
00:46:42
memory here follow tools uh embedded in the gland itself
00:46:48
that they're not outside the plan their part and parcel of structure of the land uh and uh
00:46:58
there's a a developmental association with the hair follicle
00:47:02
and ace of patients go and and the mammary gland
00:47:06
suggesting that the mammary gland is really good uh
00:47:12
in terms of the developmental position up to a problem plant um
00:47:22
this is a a turn of the century last century uh uh uh
00:47:31
drawing of the development of the uh mammary gland and i don't really wanna go or
00:47:36
starting upper left is the embryo and then it going and spread thousand plate and then
00:47:44
developers who projections that come down each of these projections
00:47:48
that comes down become one of these uh memory structures
00:47:55
so it's it's uh
00:47:59
the n. r. marceau people's uh which are like kangaroos and their
00:48:04
allies um and there's of in the middle or the picture of uh
00:48:10
so called joey in other words of any kangaroo attached to a nipple
00:48:15
um they actually do attach to the novel uh and prepared of time
00:48:21
well after the trash you can't get him off a working model can
00:48:25
come back up so that's interesting because it changes the dynamics of access
00:48:31
oh of a microbes
00:48:35
presumably
00:48:37
um
00:48:41
so the the uh uh uh kangaroos live born but they hatch from oh
00:48:47
uh actual membrane euro so sort of like there's a big blank process but
00:48:53
has before oh
00:48:56
there are some minimal possible structure and transfer so it's mostly
00:49:04
a post oh
00:49:08
part um it's mostly a memory going
00:49:11
um
00:49:13
and uh
00:49:18
there's a variation among different species ah of course
00:49:23
appeals in the upper side state percent of function
00:49:28
the nokia's words been studied is always dilute contain lactose and most act right
00:49:35
i should point out as you don't get older the mother
00:49:39
of the main internal mammary gland converse to producing a little zachary
00:49:45
uh so it's changed function the no no longer a
00:49:50
lactose and most accurate banana like a separate rich fluid
00:49:57
and as low levels of casey and whey proteins and like it a little bit in the initial secretion
00:50:05
yeah
00:50:07
i will try to explain most of this as a
00:50:11
on the left hand side of j. a. b. c. and he is a little diagram
00:50:19
oh and the right hand side exactly exactly from his all articles drawing from a based on his logical section
00:50:25
uh the mammary glands starts as a sprout that
00:50:30
he long it's down were to go from a
00:50:34
two one on the left side of me and then there are mammary glands
00:50:42
that sprout out of hand hair follicles that's proud out of the same developmental structure
00:50:49
uh and then in in c. uh
00:50:55
double hollers out a and here far also say with
00:51:00
the mammary gland is actually projecting into this how about structure
00:51:06
and then uh the nipple inverse uh and
00:51:11
the tears are shed uh and now the
00:51:16
collective force fed for the mel oh we're originally the
00:51:23
where the hair follicles i had an associate
00:51:27
so it's a very unusual thing in fact the the you probably can't see it on the lower right hand side is
00:51:34
from from work well and there's actually a hair after the
00:51:39
nipples inverted there's a hair sticking up whatever thought was work
00:51:45
excite yeah um because it's not something we can imagine that this this is
00:51:53
the new nate is you know producing nipples with here
00:52:00
hair follicles of sticking out of them
00:52:03
and then there shed and then later on as memorable
00:52:11
that's one of the things well i was working interview with this
00:52:14
that was especially surprise part was recognition that if you look at the
00:52:20
a human mammary gland development and this is not
00:52:24
found in most of the developmental biology texts on everyone
00:52:28
um the uh there are also sprouts and here on lager
00:52:35
developing from developing mammary gland so that in the lower left hand side concedes
00:52:41
thing sticking out there actually clusters of of what will become second torch issue
00:52:49
along with citations glands along with here i'm alive and of course these things are
00:52:55
sadly wrong um but it to me it shows the relationship that appears to be
00:53:01
uh in terms of the evolution of memory climbs a across cross tax
00:53:10
and this is just a schematic of of some of these things
00:53:14
which is sure shows on the top of million television has the uh
00:53:19
a. p. s. use a a hair follicles and
00:53:23
and a problem lance and then the developmental stages in
00:53:30
seven species uh showing the m. p. s. is the mammary gland
00:53:36
hi lo salacious unit developing in at various stages of development in the stacks so
00:53:45
again we have no recognised them
00:53:51
middle lower left is human
00:53:54
and that hasn't been recognised as important stage uh and of
00:54:00
course and mouse and carry don't have these stages so that ignore
00:54:07
so anyway
00:54:10
that i want to thank you for your attention ah these are uh what else singles oh
00:54:23
not put on the bottom of the world's southernmost side for lactation research 'cause i was there
00:54:32
okay so what's
00:54:34
we have about ten minutes for discussion questions
00:54:39
that's a mistake
00:54:42
yeah thank you for interesting yeah i lecture concerning the occupation
00:54:46
but as we talked last night or during agreement you know production of external secretions
00:54:53
which often russian i'm immunological impact on not restricted only to memorise
00:54:58
ah those of you who ah cop it's probably not that the crown jewel or what arguments fresh water
00:55:05
is the fishbowl simply forgotten the schools or the schools beautiful motherly and they
00:55:10
and it produces me because on its surface like all other fishes
00:55:14
in these cases but you you because when uh a little fish hatch
00:55:18
but actually the skin of the mother and father how few days
00:55:23
i'm very big the probabilities or black taking all of 'em gangs
00:55:28
in the screen and survive if they don't do that they'd ah
00:55:33
so it's uh uh i think i guess in unit and so what i see in unity
00:55:38
of of this which was very expensive because in captivity they didn't propagate pretty easily
00:55:44
but some smart guy took a regular chicken eggs makes
00:55:48
a joke senegal i put it on the market pretty dry
00:55:52
cool filled it with water and then added the fry of the you will match page and they survive
00:55:59
you got the fact as you probably know chicken x. complain a lot of antibody
00:56:03
uh you uh actually yoke ago useful of i. g. g. like molecules
00:56:09
so that's resulted in a tremendous increase in the cost of the speech
00:56:14
and now we have better varieties which do not even exist manage the second species of birds
00:56:21
a memory go out of the birds that is the uh a crop
00:56:25
uh which is the storage will very much similar to the got the bucks collect gosh you're from wood
00:56:32
ah story kinda crop and then regurgitate it to the newly hatched uh
00:56:38
parts but it's covered with antibodies because the no end of the uh crop
00:56:45
it's full of antibody producing south aspect we get into that
00:56:49
uh oh room and of the crop and therefore provide immunity
00:56:56
i'm actually pigeon mail which is that there are no in on
00:56:59
or methodology it's very much similar in its confusion to the milk
00:57:04
like what we we uh we actually do some work on ice
00:57:12
didn't matter stitches on on digits as fast as a love your perspective
00:57:20
well where did you you begin but elegant discussion of the
00:57:24
anatomical pollution in the chemical composition of the different pieces of milk
00:57:29
we can talk about in a blob lose oh settle content of any of these
00:57:35
uh do you have any thoughts about any of the distribution patterns of
00:57:39
evolution of in the middle of a somewhat animals don't tell noisy at all
00:57:44
the sea animals have some i. g. i. g. m. yeah nothing else have grown up
00:57:49
have you had any feeling about the evolution of emitted london satellite distribution of
00:57:54
even antibody t. sin function in in it
00:58:01
uh yeah i my only observation is that which i've started on that back when i started on like they should
00:58:09
uh because not think there's so many important and interesting questions and i think that you know
00:58:18
i i think it's a reasonably well known the first
00:58:21
antibody secretions even stopping for with the fishes i. g.
00:58:25
m. but more like a lot i g. i. g. a. is the outcome or only invert it starts in but
00:58:31
so it's i g. m. and n. i. g. g. like molecules lot thicker skin of the shark
00:58:37
secretions over its i. g. m. and i. g. but not right yeah yeah so
00:58:44
oh okay ah yeah sure going through the evolution microbes
00:58:54
zero huh sequences were microbes are more involved my haitian
00:59:00
um how ah lactation as we go through them millions piece
00:59:07
i think that huh
00:59:13
yeah i i i think that um
00:59:19
it has been largely overlooked and i think this is something
00:59:22
that's very crucial to the evolution of lactation and i think that
00:59:26
you know may have been behind the evolution of carbohydrates in no can many other constituency know which were
00:59:33
oh what became obvious to me and examining the evolution
00:59:37
of constituency no 'cause many of them are anti microbial originally
00:59:41
maybe not now but i think historically or
00:59:45
evolution merrily uh that this is a very important
00:59:50
relationship and i wish that we understood it better uh
00:59:53
across taxes on because i think we have this natural experiment
00:59:58
which is all the different varieties of mammals ah that
01:00:02
produce milk and that of course have to deal with uh
01:00:08
microbial
01:00:10
a species in in
01:00:13
and they've got and elsewhere and whether whether there's been you know how much of how much of this
01:00:21
you know was driven how much of the evolution of no constituents was with driven um bye
01:00:29
i'm in need for defence ah and secondarily became more important for traction
01:00:38
there was a question someone
01:00:44
no well thank you so much it was a remarkable
Conference Program
NNIW94 Opening
Dr. Natalia Wagemans, MD
Sept. 23, 2019 · 9 a.m.
Dedication to Lars A Hanson
Pearay L. Ogra
Sept. 23, 2019 · 9:10 a.m.
139 views
Key Note Lecture: The Evolution of Lactation in Mammalian Species
Olav T. Oftedal
Sept. 23, 2019 · 9:29 a.m.
678 views
Immunology of Milk and Lactation: Historical overview
Pearay L. Ogra
Sept. 23, 2019 · 11:01 a.m.
450 views
Common Mucosal Immune System
Jiri Mestecky
Sept. 23, 2019 · 1:03 p.m.
446 views
Immunomodulatory components of Human Colostrum and Milk
Helena Tlaskalova-Hogenova
Sept. 23, 2019 · 1:57 p.m.
481 views
Influence of Breastfeeding on Immune Trajectory and long-term Immune Health
Valerie Verhasselt
Sept. 23, 2019 · 3:33 p.m.
426 views
Milk and immune competence in prevention of allergy and infections
Carine Blanchard
Sept. 23, 2019 · 4:31 p.m.
511 views