Tuesday, September 27, 2016

Professions That Work With Animals

Many of us grow up loving animals and daydreaming of building a career out of working with them. But what should I be? Veterinarian? Zoo keeper? What else is there?

In fact, there are many professions that work with animals. Here are some fields to consider:


Jobs in Zoos and Aquariums:


Photo provided by Bridget Walker.
When we think of jobs in zoos and aquariums, we generally think of being a zoo keeper or aquarist (the animal care takers). Although these are generally the most visible of these positions, there are many more to keep in mind. If you like to work with animals directly, then you could be a keeper or aquarist, a veterinarian, a veterinary technician, an animal trainer, an educator, or a research biologist. If you are good at seeing the bigger picture of the mission and are destined for management, then you may be a good exhibit curator, education curator, financial manager, facilities manager, or even the director. If you are good with people, you could be a volunteer coordinator, public relations director, marketing director, special events manager, membership director, gift shop manager, visitor services manager, or personnel manager. Zoos and aquariums have many more positions that this and they all vary quite a bit in the experience and training needed and the salaries they pay. To see more, check out the Association of Zoos & Aquariums website.

Animal Health Professions:


A wildlife rehabilitator handles a baby skunk.
Image by AnimalPhotos at Wikimedia.
Veterinarians are needed wherever there are animals, so they can work in small animal clinics, animal hospitals, at farms, at zoos and aquariums, and out in the field with researchers. They can also specialize in areas such as parasitology, radiology, surgery, or dentistry. Veterinarians can’t do it alone either. Veterinary assistants, veterinary technicians and veterinary technologists all make up the teams that help diagnose and care for sick and injured animals. Wildlife rehabilitators, animal shelter workers, animal sanctuary workers and animal behaviorists specialize in caring for animals with special needs.


Animal Research:


Jérôme Micheletta with the Macaca Nigra Project
in Indonesia. Photo from Jérôme Micheletta.
Animal research takes many different forms and serves many different functions. Animal researchers doing basic research are discovering how animals’ bodies work, why they do what they do, and how they work together in their ecosystems. Animal researchers doing applied research are developing new drugs, new medical procedures and devices, new nutritional formulas, and new methods of keeping animals to make our lives and the lives of animals better. Many animal researchers work in universities as professors and scientists. Others work for the government for the Department of Natural Resources (DNR), the Environmental Protection Agency (EPA), the National Institutes of Health (NIH) or the Food and Drug Administration (FDA). Others work for private organizations such as zoos and aquariums, animal food developers, and drug development companies. All of these organizations have strict guidelines for the humane use of animals in research (often under the guidance of an Institutional Animal Care and Use Committee, IACUC), so jobs in research can include researcher/scientist, assistant researcher, animal care specialist, veterinarian, veterinary technician, surgical specialist, IACUC director or compliance director.


Working with Pets:


Snuggles! Photo by Jenna Elizabeth.
If you just can’t get enough of pets, then maybe you should work with them professionally. In addition to the care and love of their families, pets require healthcare, so many of the animal health positions above would get you lots of exposure to pets. Many pets also require the help of groomers or farriers (that fit horses with shoes) for their hygiene and animal behaviorists and trainers to help them fit in. When owners are away, many pets are in need of a pet daycare service or longer-term boarding, all of which require animal care and management staff. When people are looking for a new addition to their families and the supplies to care for them, pet adoption counselors and pet store workers are helpful. Animal wardens, animal control workers, and animal cruelty investigators all help ensure that animals are treated well.


Farming and Breeding:


Working at a dairy farm. Photo by Elizabeth Martens.
Animal farmers commonly raise dairy cows, cattle, poultry, sheep, goats, and pigs. But we don’t always think of the important roles of apiarists (bee farmers), aquaculturists (fish and seafood farmers), and specialty animal breeders. Specialty animal breeders often work privately for the pet trade, breed horses for both work and play, and work for conservation organizations. There is a wide range in animal farming and breeding practices, so research any breeding organization or company before you get involved.


Animal Behavior:


All animals behave (and misbehave), so experts in animal behavior are needed in all of the fields mentioned above. Zoos and aquariums rely on animal trainers not only to entertain the public, but also to encourage animals to cooperate with caretakers and the veterinary staff, which reduces their stress and risk of injury. Farmers, breeders and pet owners rely on animal behaviorists for the same reasons. Animal trainers also work in specialty areas, such as animal racing, showing, hunting, and acting. More noble animal professions are service animals that assist people with disabilities, police and military dogs and horses, and detection dogs and pigs. All of these highly trained animals require experienced professional trainers. Animal behavior is also an active area of animal research to provide us with insight about how and why animals (including ourselves) do what we do.

Tuesday, September 20, 2016

Risky Business: Ape Style

A reposting of an article from April, 2013


The decisions of this chimpanzee living in the
Tchimpounga Chimpanzee Sanctuary are affected
by his social situation. Photo by Alex Rosati.
If you have a choice between a prize that is awesome half the time and totally lame the other half of the time or a mediocre prize that is a sure-thing, which would you choose? Your choice probably depends on your personality somewhat. It may also depend on your needs and your mood. And it can depend on social contexts, like if you’re competing with someone or if you’re being watched by your boss or someone you have a crush on.

All animals have to make choices. Some choices are obvious: Choose the thing that is known to be of high quality over the thing that is known to be of low quality. But usually, the qualities of some options are uncertain and choosing them can be risky. As with us, the likelihood of some primates, birds, and insects to choose riskier options over safer ones can be affected by outside influences. And we aren’t the only species to have our risk-taking choices influenced by social context.

Anthropologists Alex Rosati and Brian Hare at Duke University tested two ape species, chimpanzees and bonobos, in their willingness to choose the riskier option in different social situations. They tested chimpanzees living in the Tchimpounga Chimpanzee Sanctuary and bonobos in the Lola ya Bonobo Sanctuary, both in the Democratic Republic of Congo. Most of the apes living in these sanctuaries are confiscated from poachers that captured them from the wild for the pet trade and for bushmeat. In these sanctuaries the animals live in social groups, generally spending their days roaming large tracts of tropical forest and their nights in indoor dormitories. This lifestyle rehabilitates their bodies and minds, resulting in psychologically healthy sanctuary inhabitants.

It is in these familiar dormitories that Alex and Brian tested the apes’ propensity for making risky choices. For their experimental set-up, an experimenter sat across a table from an ape and offered them two options: an overturned bowl that always covered a treat that the apes kinda like (peanuts) versus an overturned bowl that covered either an awesome treat (banana or apple) or a lousy treat (cucumber or lettuce). In this paradigm, the peanut-bowl represents the safe choice because whenever the ape chooses it, they know they’re getting peanuts. But the other bowl is the risky choice, because half the time they get fruit (yum!), but the other half of the time they get greens (bummer).

This figure from Rosati and Hare's 2012 Animal Behavour paper shows Alex
demonstrating the steps they would go through before the ape chose one of the two options.

After spending some time training the apes to be sure they understood the game, the researchers tested their choices in different social situations. In each test session, the ape was allowed to choose between the two bowls (and eat the reward) multiple times (each choice was called a trial). But before the test session began and in between choice trials, another experimenter sat with the ape for two minutes and did one of three things: In one group, the experimenter sat at the table and silently looked down (they called this the “neutral condition”). In another group, the experimenter repeatedly offered the ape a large piece of food, pulling it away and grunting whenever the ape reached for it (they called this the “competitive condition”). In a third group, the experimenter tickled and played with the ape (they called this the “play condition”).

Alex and Brian found out that whereas bonobos chose the safe option and the risky option about equally, the chimpanzees were significantly more likely to choose the risky option. But despite this species difference, both species chose the risky option more often in the “competitive condition”. Neither species increased their risk-taking in the “play condition”.

The graph on the left shows that wheras bonobos chose the safe option and the risky option each about 50% of the time (where the dashed line is), the chimpanzees chose the risky option much more often. The graph on the right shows that both species chose the risky option more often in the "competition condition" than they did in the "neutral condition". Figure from Rosati and Hare's 2012 Animal Behavour paper.

These are interesting findings, especially when you consider the natural behaviors and lifestyles of these closely related species. Bonobos can be thought of as the hippies of the ape world, happily sharing and using sex to settle disputes and strengthen relationships. In comparison, chimpanzees are more like gangsters, aggressively fighting over resources and dominance ranks. So in general, the more competitive species is more likely to take risks. But when the social environment becomes more competitive, both species up the ante. This effect doesn’t seem to be simply the result of being in a social situation, because the apes didn’t increase their risk-taking in the presence of a playful experimenter.

This still leaves us with some questions to ponder though. Are apes more likely to take risks when an experimenter is offering food and taking it away because of a heightened sense of competition, or is this the result of frustration? And would we see the same effect if the “competitor” were another ape of the same species, rather than a human experimenter? How would their behavior change if they were hungry? These questions are harder to get at, but this research does demonstrate that like in humans, the decision-making process in chimpanzees and bonobos is dependent on social context.


Want to know more? Check this out:

Rosati, A., & Hare, B. (2012). Decision making across social contexts: competition increases preferences for risk in chimpanzees and bonobos Animal Behaviour, 84 (4), 869-879 DOI: 10.1016/j.anbehav.2012.07.010

Tuesday, September 13, 2016

Cow Pies Can Make You Smarter and Less Stressed

A reposting of an article from August, 2015

It seems like everyone is running around buying school supplies and books, registering for classes, and fretting about how hard it is going to be to learn another whole year’s worth of stuff. The secret to success, it turns out, may lie in cow dung.

A cow pie. Photo taken by Jeff Vanuga at
the USDA available at Wikimedia Commons.
Recent research has highlighted the important role that microbes living in animal digestive tracts have on host animals’ health and behavior. This influence of our gut microbes on our behavior is called the microbiota-gut-brain axis. Many of these microbes have long-standing populations that reproduce and spend their whole lives in our guts. Because our digestive tracts do not have much oxygen, these species are anaerobic (do not require oxygen to live). However, our gut communities also have more transient aerobic members (species that do require oxygen to live) that come in when they are ingested and die or leave with the droppings. One of these transient aerobic intestinal citizens is Mycobacterium vaccae (or M. vaccae for short), an aerobic bacterium that naturally lives in soil, water, and yes, cow dung.

When mice are injected with heat-killed M. vaccae, they develop an immune response that activates their brain serotonin system and reduces signs of stress. Serotonin is a neurotransmitter that is found in the brain and is involved in regulating alertness, mood, learning and memory. In fact, many antidepressant drugs work by increasing the amount of available serotonin in the brain. Interestingly, serotonin is also found in the digestive system, where it plays a role in digestive health. Since M. vaccae can increase serotonin function, and serotonin reduces anxiety and improves learning, researchers Dorothy Matthews and Susan Jenks at The Sage Colleges in New York set out to test whether eating live M. vaccae could reduce anxiety and improve learning in mice.

A drawing of the mouse maze used by Dorothy and Susan.
This image is from their 2013 Behavioural Processes paper.
The researchers developed a Plexiglas mouse-maze with three difficulty levels, where each increase in difficulty was marked by more turns and a longer path. They encouraged the mice to run the maze by placing a tasty treat (a square of peanut butter on Wonder Bread™) at the end of the maze. Half of the mice were given live M. vaccae on the peanut butter and bread treat three weeks and one week before running the maze, and then again on each treat at the end of each maze run. The other half were given peanut butter and bread without the bacterial additive. The mice then ran the maze roughly every other day: four times at level 1, four times at level 2 and four times at level 3. Each maze run was video recorded and the researchers later watched the videos to count stress-related behaviors.

The mice that ingested M. vaccae on their peanut butter sandwiches completed the maze twice as fast as those that ate plain peanut butter sandwiches. They also had fewer stress-related behaviors, particularly at the first difficulty level of the maze when everything was new and scary. In general, the fewer stress behaviors a mouse did, the faster its maze-running time was. The mice that ate the M. vaccae also tended to make fewer mistakes.

The researchers then wanted to know how long the effects of M. vaccae lasted. They continued to test the mice in the same maze, again with four runs at level 1, four runs at level 2 and four runs at level 3, but for these maze runs no one was given the M. vaccae. The mice that had previously eaten the M. vaccae continued to complete the maze faster and with fewer mistakes and to show fewer stress-related behaviors for about the first week before the M. vaccae effects wore off.

What does this all mean? It means eating dirt isn’t all bad (although I don't recommend eating cow poop). Letting yourself get a bit dirty and ingesting some of nature's microbes could even help you learn better, remember more, and stay calm - especially in new situations. Just something to think about as the school year gets started.


Want to know more? Check these out:

1. Matthews, D., & Jenks, S. (2013). Ingestion of Mycobacterium vaccae decreases anxiety-related behavior and improves learning in mice Behavioural Processes, 96, 27-35 DOI: 10.1016/j.beproc.2013.02.007

2. Lowry, C., Hollis, J., de Vries, A., Pan, B., Brunet, L., Hunt, J., Paton, J., van Kampen, E., Knight, D., Evans, A., Rook, G., & Lightman, S. (2007). Identification of an immune-responsive mesolimbocortical serotonergic system: Potential role in regulation of emotional behavior Neuroscience, 146 (2), 756-772 DOI: 10.1016/j.neuroscience.2007.01.067

Tuesday, September 6, 2016

Need a Hand? Just Grow it Back! How Salamanders Regenerate Limbs (A Guest Post)

By Maranda Cardiel

(A reposting of an original article posted on February 29, 2016)

How cool would it be if you could regenerate your own body parts? Just imagine: you are chopping up some carrots for dinner, but whoops! You accidentally cut off your thumb! No worries, it’ll grow back in a few weeks, good as new and fully functional. No need to take a trip to the hospital and pay all of those annoying medical costs.

That all sounds pretty nifty, but that can’t actually happen, right? Tissue regeneration on that large of a scale is something you can only find in science fiction. …Or so you may think. Nature has actually found a way to regenerate full limbs and other body parts after they have been completely amputated. However, among animals with spines, this unique ability is only found in salamanders. But how does it work, and why can’t we do it too?

A cartoon illustrating examples of the three different methods of tissue regeneration in animals. A.) An
adult hydra being cut into two pieces and regenerating into two separate hydras. B.) Part of a human
liver being cut off and the remaining liver regenerating via cell division. C.) A salamander’s arm being
amputated and undergoing epimorphosis to regenerate an entire new arm.
Source: Maranda Cardiel

There are actually three ways that animals can regenerate tissues. Some animals, such as hydras, can use the tissues they already have to regenerate themselves after being cut in two, resulting in two separate hydras. Mammals, including humans, have the ability to regenerate their livers by having the liver cells divide into more liver cells. This is how liver transplants work – a portion of liver from a live donor will grow into a fully-functioning liver in the recipient. The third method is called epimorphosis, which is the ability to change existing cells of specific types so that they can re-grow as different cell types, and this is what salamanders are able to do.

When the limb of a salamander is cut off, only the outermost layer of skin moves to cover the wound. This single layer forms a special skin cap known as the epithelial cap, and the nerves at the amputation site shrink back from the wound. Then the cells beneath the cap dedifferentiate, losing their specific characteristics so all of the different types of cells become the same and detach from each other.

A cartoon illustrating the process of a salamander regenerating its arm. A.) The limb is amputated.
B.) The outermost layer of the skin begins to cover the wound. C.) This single layer of skin creates
an epithelial cap and the blastema forms underneath it. D.) The cells of the blastema begin to
differentiate into bone, nerves, etc. E.) The cells continue to divide and differentiate until the limb is
fully formed. Source: Maranda Cardiel

Now the amputated limb has a mass of indistinguishable cells under the cap, and this mass is called the regeneration blastema. A blastema is simply a clump of cells that is able to grow into an organ or body part. Over the course of several weeks, this blastema divides into more cells and the cells begin to differentiate - or turn into multiple types - again, forming different cell types such as bone, muscle, cartilage, nerves, and skin. Eventually, the salamander will have a brand new limb.

The salamander’s body can even tell what body part it’s supposed to re-grow; if it’s amputated at the wrist it will grow a new hand, and if its entire hind leg is amputated it will grow a new hind leg. And it’s not only limbs that salamanders can regenerate – they can even grow back their tails, retinas, spinal cords, and parts of their hearts and brains!

As you can see, the process of epimorphosis is much more complicated than simply having a single cell type divide a lot. It also requires certain chemicals and patterns of immune signaling to work properly. But why can’t people do this too? One of the reasons is because when our tissues are damaged, all of our skin grows to cover and heal the wound, which forms scars. In salamanders, only the outermost layer of skin does this, which prevents the scarring that would stop tissue regeneration. The salamander’s immune system is also regulated differently than our own, which allows them to regenerate whole body parts.

Unfortunately we are not salamanders, so when you cut off your finger it’s not going to grow back. But researchers are continuing to study salamanders and their astounding regenerative abilities in the hopes of finding a way to apply it to people. Who knows, maybe someday we’ll be able to grow back our own limbs too.


Sources:

Gilbert, Scott F. Developmental Biology 6th Edition. Ncbi.nlm.nih.gov. National Center for Biotechnology Information, 2000.

Godwin, J., Pinto, A., & Rosenthal, N. (2013). Macrophages are required for adult salamander limb regeneration Proceedings of the National Academy of Sciences, 110 (23), 9415-9420 DOI: 10.1073/pnas.1300290110

Thursday, July 7, 2016

Summer Vacation!

It is time for this blogger to unplug and unwind! But don't worry, I will be back in September with more stories of why animals behave the way they do, how their bodies function, and how to pursue your animal-related dreams.

Be curious!