TWiV 781: My genome is left to tell the tale

July 18, 2021

The Team with Invincible Values discusses whether dogs or cats passively carry SARS-CoV-2 on hair and foot pads, maternal to fetal transfer of antibodies in infected or vaccinated pregnant women, and evidence that retroviruses infected cetaceans before and after they moved into the oceans.

Hosts: Vincent Racaniello, Dickson Despommier, Alan Dove, and Brianne Barker

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Weekly Picks 1:30:44

DicksonCurrent Map | U.S. Drought Monitor
BrianneA comic strip about immune responses
AlanSuperliminal game
VincentBirds are dying in NJ

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Intro music is by Ronald Jenkees

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8 comments on “TWiV 781: My genome is left to tell the tale

  1. Richard Cornell Jul 19, 2021

    The State lawmakers are Republicans, and God will protect all of the State citizens from every virus that has ever been and possible all of God’s virus that are to come.
    If I’m wrong about God protecting its citizens of the State, I’m sorry about the number of the painful deaths that will occur. But they have been warn that nasty viruses like COVID-19 will kill you off if not vaccinated. It is one way that the Democrats will take control of the State Senate if all the Republicans are dead.
    Guess it is up to God on how many will died.

    • Judith Stapleton Jul 20, 2021

      Please see Youtube interview of Dr David E Martin with the legal team in Germany led by Dr Reiner Fuellmich

  2. I’m sorry to so out of line when it comes to people who refuse to get vaccinated, but have worked in the medical field myself and seen children so infected when by childhood diseases that could have been stopped if only their parents care about the health of their children. It will be sad when parents die off and leave their children in the hands of others.

  3. Wayne Hamilton Jul 19, 2021

    +1 for Mountain. I have 6 of their LPs.
    My favorite songs are probably “Mississippi Queen” and “Theme From An Imaginary Western”.

    and +1 for manual transmission 🙂

    I’m vintage 1952.

  4. Jeffery Biss Jul 20, 2021

    All whaling should be ended, including that of indigenous peoples. Whaling is brutal and whales have the same rights that we claim for ourselves because we consider ourselves moral. We can’t claim for ourselves that which we deny to others.

    Indigenous people are also human beings and so they are part of the problem. The human biomass is estimated at 0.06 GtC and that of our livestock is 0.1 GtC while that of all wild mammals is 0.007 GtC. Many wildlife populations have been in decline for decades as our population has grown and we have increased our use of earth’s resources and destroyed wildlife habitat.

    Therefore, there is absolutely no valid claim that any human is “part of nature” as our population is so out of whack compared with that of our wild brethren that we need to do something to reverse the human load, such as enacting policies to get people to stop having kids, such that the wild world can recover.

  5. Stephanie Jul 20, 2021

    Regarding crossing the placenta of different animals – it depends – various mammals have different types of placentas, with differing cell layers. (veterinarian+virologist here).

    • John Barlow Jul 26, 2021

      TWiVers (81F and sunny here in VT, and I have been catching up on past episodes while doing yard work, so a bit of a delay responding here). Glad someone else started to chime in on this topic… a bit more detail…

      For many species there is no trans-placental passive transfer of immunoglobulins. It all depends on the type of placenta, and more specifically the number of tissue layers comprising the placenta. In fact for most of our domestic animal species there is little to no trans-placental transfer of immunoglobulins, and either all or most of passive transfer of immunity occurs via colostrum. True for horses, pigs, ruminants (cows, sheep, goats), camelids (camels, llamas and alpacas), and related wild animals such as deer, buffalo (i.e. all ungulates) (Elephants are one species that I believe have a significant amount of placental transfer, there are always exceptions to the “rules”). So many species depend on colostral antibodies for passive transfer, that we might say humans (and other primates) and some rodents (rabbits and Guinea pigs) are the exception. Carnivores (dogs and cats) have a small to moderate amount of trans-placental transfer (5-15% of neonates’ immunoglobulins), so they too depend on colostrum for passive immunity. Neonatal rats and mice receive passive immunity from both trans-placental transfer and via colostrum.
      Post-natal failure of passive transfer is a major reason for morbidity and mortality in domestic species such as cattle. Also, there is a window for gut absorption of immunoglobulins, within the first 24 to 48 hours (earlier is better) after which there is “gut closure” and limited absorption (don’t get me going about gut closure). Brianne was right on regarding the mechanism of trans-placental transfer in humans, receptor mediated transcytosis via FcRn (n for neonate). IgGs are primarily transferred during gestation (last third), with IgG1 being the transported most efficiently. Immunoglobulin concentrations in colostrum also differ among species. For example, concentrations of IgG, IgA and IgM in humans are 0.43, 17.40, and 1.60 mg/ml, respectively, while in cows they are 50.50, 3.90 and 4.20 mg/ml, respectively (I had to look these numbers up in one of my lactation textbooks, Lactation and the Mammary Gland by Mike Akers, recently retired from Virginia Tech). Passive transfer in calves is so important that we have established “calf-side” tests to measure serum total protein as a proxy for failure of passive transfer in the neonate. Calves that did not receive adequate high quality colostrum will have a low total serum protein because they lack the gamma globulins, and they are at increased risk for neonatal diarrhea and respiratory disease. Vincent asked, what about kangaroos? It seems most marsupials receive passive transfer from milk while they are in the pouch stage of development, although some species may receive some transplacental transfer (again, depends on placenta type). And since there was a paper on marine mammals in this episode, what about passive transfer among these species? It seems for where it is known, the majority of seals, whales and dolphins are born with low serum IgG and acquire immunoglobulins from milk after birth. By the way, the diversity in lactation strategies among the seals and sea lions is amazing, but that is another story from my days of teaching a course on lactation!

      Best Regards and keep up the great work (TWiM, TWiV and TWiEVo fan, Vermontah, veterinarian (dairy cattle), epidemiologist, with some not to distant past immunobiology and lactation biology work!)

  6. Vincent, Alan, Dickson, and Brianne:
    We have spent the past week working toward COVID-19 mitigation strategies in our community, and I just flipped on Sunday’s TWiV (today is Wednesday). Not surprisingly, Tennessee was one of your topics. You’ll be glad to know that your opinions are respected and shared by the professionals in our county.
    Tennessee has an interesting state health department reach: while smaller counties follow the direction of the state, counties including Hamilton (where we live in Chattanooga) can follow the directives of the local health department. The Chattanooga/Hamilton County health department is proudly continuing to advise childhood vaccination and vaccination against COVID-19 and has had two such events in the past week.
    As far as our strategies go, we continue to advise the county mayor and schools, plus Purdue University and our other schools and businesses, and are taking the Delta variant seriously. 100% of sequencing done locally is the Delta variant, and hospitalizations are following the same curve as Springfield right now.
    Thanks for continuing to educate us all–without you, we couldn’t do our job. As always, we believe it can be done: school, work, you name it, and vaccination along with basic mitigation is our strategy.
    Your friends in Chattanooga,
    Lisa Smith and David Bruce