So three straight female calves from Mabu and Litsemba at Reid Park. Certainly not the least bit disappointing - the future of Reid Park's herd is bright.
Amazing news for sure!
Pure luck. Boys and girls are usually 50/50.Besides pure luck, is there any way to guarantee a girl calf or no?
Although, some scientists/reproduction specialists believe weight has a play in it. I’d have to find it again but there was one or two studies that showed heavier cows tended to throw more bulls and skinnier cows threw more cows. Which would make sense because males on average eat more so times with plentiful resources in the wild would be perfect for raising bulls. I personally don’t believe it as if I’m not mistaken males decide the gender by whatever sperm makes it all the way but still an interesting theory.Pure luck. Boys and girls are usually 50/50.
I have also heard that AI has a significantly higher chance to have a male calfPure luck. Boys and girls are usually 50/50.
While I am not an expert in elephants, it is generally understood that there can, in some species, be factors other than XX/XY which determine the sex of offspring. While at the core level, you are absolutely correct that whichever sperm makes it all the way will determine the sex of the offspring, environmental conditions inside the female can sometimes favor XX sperm or XY sperm, making it more likely that is the sperm to succeed. Generally, it would be something like hormonal levels to determine this (and not strictly reproductive hormones- stress hormones play a role too), as hormones can adjust the pH and other internal conditions. While I'm not sure if weight could play a role in changing the internal conditions to favor XY sperm, it is certainly a plausible hypothesis.Although, some scientists/reproduction specialists believe weight has a play in it. I’d have to find it again but there was one or two studies that showed heavier cows tended to throw more bulls and skinnier cows threw more cows. Which would make sense because males on average eat more so times with plentiful resources in the wild would be perfect for raising bulls. I personally don’t believe it as if I’m not mistaken males decide the gender by whatever sperm makes it all the way but still an interesting theory.
I’ll look for the study today but if anyone would like to beat me to it I know Janine Brown is one of the people who wrote it, however she’s written or been a part of hundreds of elephant repro papers so it’ll be tough lol. But yes their cortisol levels were one of the things tracked and it’s believe that the higher cortisol levels that come with having less resources played an impact in the sex of calves. Fascinating research all together though, and tbh I wish we could advance AI to the same level as with cows and humans where we can basically chose the sex and implant that embryo. Would be a GAME CHANGER imo.While I am not an expert in elephants, it is generally understood that there can, in some species, be factors other than XX/XY which determine the sex of offspring. While at the core level, you are absolutely correct that whichever sperm makes it all the way will determine the sex of the offspring, environmental conditions inside the female can sometimes favor XX sperm or XY sperm, making it more likely that is the sperm to succeed. Generally, it would be something like hormonal levels to determine this (and not strictly reproductive hormones- stress hormones play a role too), as hormones can adjust the pH and other internal conditions. While I'm not sure if weight could play a role in changing the internal conditions to favor XY sperm, it is certainly a plausible hypothesis.
It has long been hypothesized in baboons whether or not additional factors, such as dominance rank or resource availability, play an indirect role in sex determination through the female's stress hormone levels, and while the data for this is inconsistent and still heavily debated (over 40 years after it was first proposed!), the general idea that there could be other factors which favor whether XX sperm or XY sperm is successful is certainly not a new one, and one that has been proposed in a wide range of mammal species. This article on reindeer might be of interest: https://royalsocietypublishing.org/doi/full/10.1098/rspb.2005.3330, or this one on mice: https://royalsocietypublishing.org/doi/full/10.1098/rspb.2019.2909#d36365360e1
Let's leave at least the sex determination of elephants to nature. And not to the people who already influence their lives too much...I’ll look for the study today but if anyone would like to beat me to it I know Janine Brown is one of the people who wrote it, however she’s written or been a part of hundreds of elephant repro papers so it’ll be tough lol. But yes their cortisol levels were one of the things tracked and it’s believe that the higher cortisol levels that come with having less resources played an impact in the sex of calves. Fascinating research all together though, and tbh I wish we could advance AI to the same level as with cows and humans where we can basically chose the sex and implant that embryo. Would be a GAME CHANGER imo.
With all due respect, if this is something we could influence with reliable results, it would be like finding the Ark of the Covenant as far as elephant management goes.Let's leave at least the sex determination of elephants to nature. And not to the people who already influence their lives too much...
It has been successful in other species, bottlenose dolphins have been sex selected via AI.With all due respect, if this is something we could influence with reliable results, it would be like finding the Ark of the Covenant as far as elephant management goes.
I'm a little puzzled by the line you are drawing here. From a welfare perspective, I think artificial insemination is something that can legitimately be questioned. I'm not taking a position on it here, but an argument could easily be made as to how AI unnecessarily infringes on an animal's sense of choice and control or in how it is wrong to force a pregnancy in an "unnatural" manner. Not saying I agree with these arguments, just that it's a relatively easy argument to make. For better or for worse, AI is undeniably a valuable management tool in zoo populations where it has been successful, however, and if AI is to occur, I don't see how selectively inseminating with male versus female sperm is any different than inseminating indiscriminately, at least on the elephant's side of things. It isn't like the elephant is consciously choosing to have a male or female calf. If you have a non-welfare based argument against sex determination, but for artificial insemination, I'd love to hear it, but I definitely think it is an odd place to draw the line.Let's leave at least the sex determination of elephants to nature. And not to the people who already influence their lives too much...
My only quibble is that I do hope that Louisville doesn't get "stuck" on the idea of having a multigenerational herd of elephants if it really does want to stick with elephants in the future, and not just, reuse the space the elephant exhibit currently takes up for another species.
The zoo's statement about their potential future with elephants now says that any future exhibit would be build to house a multigenerational herd AND a bull group!
(As seen at the bottom of this page)
Follow Our Elephant’s Journey
It definitely didn't sound like their master plan was final in their responses about a potential elephant exhibit. They wouldn't be the first zoo to re-do their master plan several times, and its likely we'll see several popping up before a final one is decided.Frankly, unless Louisville completely redoes it's master plan again, I just can't see them being able to house both a multigenerational herd and bulls in such a small area.
Tbh, I think 3-ish acres is fine if the space is interesting enough (if we're talking 3 acres of just yard space).It definitely didn't sound like their master plan was final in their responses about a potential elephant exhibit. They wouldn't be the first zoo to re-do their master plan several times, and its likely we'll see several popping up before a final one is decided.
I would imagine that the zoo believes it's possible to have a large exhibit in some version of a masterplan, since a 3ish acre exhibit isn't nearly up to par with the standards of new exhibits nowadays. I'm still pretty skeptical myself, but elephants are a huge draw and it wouldn't surprise me in the least if they pulled a Smithsonian and went all in on elephants over other species.
I'm a little puzzled by the line you are drawing here. From a welfare perspective, I think artificial insemination is something that can legitimately be questioned. I'm not taking a position on it here, but an argument could easily be made as to how AI unnecessarily infringes on an animal's sense of choice and control or in how it is wrong to force a pregnancy in an "unnatural" manner. Not saying I agree with these arguments, just that it's a relatively easy argument to make. For better or for worse, AI is undeniably a valuable management tool in zoo populations where it has been successful, however, and if AI is to occur, I don't see how selectively inseminating with male versus female sperm is any different than inseminating indiscriminately, at least on the elephant's side of things. It isn't like the elephant is consciously choosing to have a male or female calf. If you have a non-welfare based argument against sex determination, but for artificial insemination, I'd love to hear it, but I definitely think it is an odd place to draw the line.
Just having seen the blog post and the master plan, I don’t think elephants would be in Louisville’s futureThe zoo's statement about their potential future with elephants now says that any future exhibit would be build to house a multigenerational herd AND a bull group!
(As seen at the bottom of this page)
Follow Our Elephant’s Journey
If the zoo didn't think they had the ability to house elephants again, then they wouldn't have stated that it's a possibility.Just having seen the blog post and the master plan, I don’t think elephants would be in Louisville’s futureYes master plans change all the time and sometimes they have animals from their current collection on the plans, assuming they will have some still at their facility when they made plans. But seeing how they will repurpose it for rhinos, I don’t feel too strongly they will be returning. They mention how if they’re to hold them, they would require to have space for both multigenerational herd and bulls. That’s quite a tall order and just reading their statements so far, I’m inclined to believe they may not unfortunately.