Shark DNA Used to Buff Up Aquacultured Fish

It’s not every day that catching up on scientific literature causes you to almost do a spit-take on your laptop screen.  This happened to me recently due to the weird and wild world of aquaculture.  Aquaculture is the practice of growing aquatic animals such as fish and shellfish for the purpose of food, and has been held up as both a savior and destroyer of the marine ecosystem.  To get an idea of what this generally looks like (at least here in the U.S.), Amy has a whole series of posts on aquaculture operations in North Carolina.

As with land-based farming, aquaculturists are motivated to find ways to increase the food value of their stock.  The methods used are varied, from high-protein feed mixes to genetic manipulation.  Recently, farmed salmon genetically-modified to grow larger and faster than their wild conspecifics have been approved for human consumption by the FDA, though not without debate.  This man-made subspecies was created by modifying the already-existing DNA of the fish, but what if it turned out that simply injecting DNA from a different species could improve the growth and protein output of farmed fish?  And what if that foreign DNA came from sharks?

Read More

The Trouble with Teacup Pigs

I adore Here Comes Honey Boo Boo. That’s right, I said it. There’s a soft spot in my brittle old heart for that whole family, Sugar Bear, Mamma June, and all. Especially Glitzy.

Glitzy the Pig. Image from The Learning Channel.

Glitzy, for those of you who don’t know, is a “Teacup” Pig (as you can tell from the video, pigs don’t like to be held). Pigs are cute. Piglets are super cute. Pigs are very intelligent, highly social, and make surprisingly good, house-trainable pets. Unfortunately, 800-lb hogs are not cute. Over the years, various breeders have tried to create pigs that retain all of the adorableness of a piglet without reaching the potential half ton plus mass of a full grown adult hog. Among the most popular “miniature” is the Vietnamese pot-bellied pig, a delightfully spry porcine that tops the scales at a manageable 300 pounds. When legitimate breeders talk about miniature pigs, they’re talking about these 300-lb cuties. Pot-bellied pigs are surprisingly diverse, and, although extremely rare, adults have been reported as small as 20 pounds (most breeders would regard an adult pig that size to be extremely malnourished). This huge size range prompted many breeders to attempt to create even smaller pig breeds, selecting from only the smallest stock. Enter the teacup pig.

A teacup pig (or a micro pig, nano pig, or any of a half dozen variations of “small”) is supposedly a tiny pig breed. Some breeders claim that their pigs only reach up to 30 pounds in weight. Combined with the intelligence and sociability that pigs possess, it would seem that teacup pigs should make a perfect pet. There is only one problem: there’s no such thing as a teacup pig.

Read More

Chemistry of the Great Big Blue: A Pesticide Mystery

As part of my ongoing community-based research on water quality in coastal North Carolina, I ended up tasked with answering what I thought would be  a very basic question: what is the predominant pesticide used in my county? The largest farm and by far the largest amount of cropland is occupied by a traditional corn/soy rotation with the occasional cotton thrown in. Given the multitude of American acres donated to corn/soy, I figured I could easily find out the basics of that crop’s chemistry. Not so. My little information adventure has made me realize why there are so many rumors surrounding farming’s impact on water quality in the region. Rumors are easier to find than facts.

Read More

That sinking feeling: Hog lagoons, superbugs, and the proliferation of antibiotics in livestock

From here, it looks like such a lovely pond. Photo by Andrew David Thaler

From here, it looks like such a lovely pond. Photo by Andrew David Thaler

The murky brown water was still, reflecting, perfectly, the drifting clouds above. Had I not known what it was, an acre-wide manmade pond almost a dozen feet deep filled to the brim with hog feces, I might be tempted to describe it as “beautiful”. Hog lagoons like this are a common sight in North Carolina, though their use is in decline. My lab group arrived at this particular lagoon to take microbial samples, fungi in this case, from the steaming cauldron of organic waste: an ideal culture medium. Carefully, we loaded a small skiff and rowed out into the stink. Near the center, we gingerly dipped our sampling vials, affixed to the end of an old fishing pole, into the dense fluid. It was then that we noticed the rising waterline, the slow trickle at the stern, the shift in balance. We locked the oars and rowed, frantically, towards shore. Our labmates on shore had, thankfully, tied a line to the bow before we departed. The skiff’s gunwales were creeping closer and closer to the water. We were sinking. We were sinking in a lake of pig shit.

Read More