Ovariohysterectomy versus Ovariectomy

At first glance, the terms "ovariohysterectomy" and "ovariectomy" look similar enough that you might think they refer to the same procedure, but that is not the case.

An ovariohysterectomy (OHE) is what we think of as a traditional spay where both ovaries and the uterus down to about the level of the cervix is removed. An ovariectomy (OE) is simply the removal of both ovaries while leaving the uterus in place.

In the United States, the OHE has long been and still is the surgery of choice when it comes to eliminating a female dog or cat’s ability to reproduce and preventing some common diseases of the reproductive tract (e.g., uterine infections and breast cancer). This might be changing, however. In other parts of the world, the OE is the more common surgery as long as a pet’s uterus is healthy. More veterinarians in the US are starting to move in this direction too, which can lead to questions from owners who are not familiar with OE surgeries.

The main benefit of an OE versus an OHE is the ability to perform the surgery through a smaller incision. This incision can also be locate a little farther forward on the pet’s abdomen, which improves the surgeon’s ability to locate, manipulate, and surgically remove the ovaries. This could potentially reduce surgery times, surgical complications, and the amount of discomfort a pet feels postoperatively, although the few studies that have looked into these factors have not shown a significant difference between OEs and OHEs. This could change, however, as a greater number of surgeons become more familiar and practiced in OE techniques.

Owners are often concerned that leaving the uterus in place increases the chance that their pets could develop uterine disease in the future. The two biggest issues are pyometra and uterine cancer.

Pyometras can only develop in a dog that is under the influence of progesterone. Progesterone is made by the ovaries, so as long as both ovaries are completely removed and a dog is not treated with a medication containing progesterone (something which is almost never done), a pyometra will not occur. Relying on OHEs is not completely protective either. We can and do see something called a “stump” pyometra (i.e., infection involving the small part of uterus that remains after an OHE) when a piece of ovarian tissue is mistakenly left behind during surgery or progesterone is supplied exogenously.

Uterine tumors are very rare in dogs and cats, and they also seem to be under hormonal influence. Therefore, removing a pet’s ovaries at a relatively early age should even further reduce the chances of their forming if the uterus is left in place. The most common type of uterine tumor is a leiomyoma, which is benign, so in the unlikely event that one should form, removing the uterus at that time should be curative.

What this all boils down to is that both OHEs and OEs can be an effective form of surgical sterilization, but the OE may have some potential benefits, particularly when performed by an experienced surgeon. Dr. Jennifer Coates

China confirms bird flu outbreak in Tibet

BEIJING - China's Ministry of Agriculture on Monday confirmed an outbreak of bird flu at a village in Lhasa, Tibet autonomous region.

Laboratory tests showed that the highly pathogenic H5N1 avian flu killed 290 fowls raised by farmers in the Sangda village of Doilungdeqen county on December 2, said an official with the ministry who declined to be named.

The epidemic is under control and no abnormal physical conditions were reported in people who had close contact with the dead birds, said the official.

Authorities have sealed off and sterilized the infected area, where 1,575 fowls were culled and safely disposed of in order to prevent the disease from spreading.

Bird flu, or avian influenza, is a contagious disease of animal origin caused by viruses that normally infect only birds and, less commonly, pigs. It can be fatal to humans.

Mystery disease strikes arctic seals

FAIRBANKS, Alaska, Dec. 12 (UPI) -- Veterinarians in Alaska say they don't know what has killed almost 200 arctic ringed seals since July, with similar deaths reported in Canada and Russia.

The mystery ailment causes the animals' hair to fall out and ulcers to develop on their skin and flippers, and necropsies have revealed lesions on their lungs, livers, hearts and brains, NewScientist.com reported Saturday.

"We don't know what's causing it," Julie Speegle of the US National Oceanic and Atmospheric Administration's office in Alaska said, adding tests have ruled out viruses that killed hundreds of seals in Europe in 1988.

Vets said they were screening for other viruses, bacteria and fungi, and for algal and other toxins that may be responsible.

The disease may have spread to other species including spotted seals, bearded seals and walruses, and NOAA has advised hunters not to eat any sick seals in case the agent can also infect humans.

Animals use tunnels to get to the other side of road

University of Maryland Center for Environmental Science - A great blue heron walks through a tunnel under a Maryland highway. According to a study by the University of Maryland Center for Environmental Science, almost 60 different specices use the culverts. You probably know this old riddle: Why did the chicken cross the road?
But have you heard this one: How did the raccoon (and deer and blue heron) cross the road?

Through the tunnel, of course!

It turns out that an amazing number of animals use tunnels as a way to get from one side of a busy road to another.

Professor Ed Gates, at the University of Maryland Center for Environmental Science, just completed a two-year study of how animals in the state use special tunnels called culverts, which are created to let water drain under highways.

Gates and his team of researchers put motion- and heat-activated cameras in 265 culverts in every county in Maryland. The result: more than 33,000 images of identifiable animals using the tunnels to get to the other side of the road. In fact, they logged 57 species of animals. They didn’t snap pictures of black bears, coyotes and bobcats. But “that doesn’t mean they don’t use them; we just didn’t get a picture,” Gates said.

Culverts are made of different materials and come in different shapes and sizes. Sometimes that matters to the animals, researchers discovered. For example, Gates said, “raccoons will use any type of culvert,” but blue herons look for culverts “big enough so they can spread their wings out.” And deer avoid tunnels that have rocky bottoms because “their feet can get caught between the rocks,” Gates said.

Crossing busy roads by using tunnels seems to be a family affair, the researchers learned. “A lot of animals take their young through the culverts,” Gates said, noting that they got pictures of does leading fawns and ducks leading ducklings through the tunnels. Gates compares it to your mom telling you to look both ways before crossing the street: “When you see a young animal with an adult, [you assume that] the young animal has to be learning that this is a good way to get across.”

Because the tunnels are a necessary part of road construction, Gates said, he hopes the information learned from the study can be used to create new culverts that make it easier for animals to avoid the roads.

That’s important for humans, too, Gates points out. “People can be injured when they try to avoid hitting a deer,” he said before adding, “it’s obviously beneficial to the animals as well.” Tracy Grant

Wild Monkeys to Aid Radiation Research Efforts

Measuring the radiation leaked from the Fukushima Daiichi plant has been a mammoth task that has everyone from manufacturers, volunteer scientists and young mothers pitching in to keep track of the scatter. Now some researchers are even looking to wild monkeys and possibly wild boars to help monitor the contamination.

Researchers from Fukushima University plan to kit wild monkeys out with radiation-measuring collars to track the contamination levels deep in the forests, where it’s difficult for humans to go.

Takayuki Takahashi, a robotics professor at Fukushima University who is the lead researcher on the team, said that, while radiation conditions in the forest have been studied from the air, there is a dearth of data on what it is like on the ground, in close proximity to the wildlife.

Returning the monkeys to the forest equipped with these measuring devices may reveal the long-term effects of radiation on animals, as well as how radiation spreads in the forest as it is transferred from plants to animals and vice versa. It can also shed light on the little-studied subject of internal exposure to radiation by studying the consequences of animals consuming radiation-tainted plants or prey, according to Mr. Takahashi. “As the radiation moves from the ocean to the forest, it is important to set a baseline of knowledge to see how it affects humans and animals in the long run,” said Mr. Takahashi, who, like other Fukushima University professors, is applying his expertise to radiological studies for the first time in his career in the wake of the nuclear accident. The university is located about 70 kilometers from the Fukushima Daiichi plant.

The monkey collars are geared with a small radiation-measuring device, a GPS system and an instrument that can detect the monkey’s distance from the ground as the radiation level is being tallied. Mr. Takahashi said more contraptions may be added, but these will be the three main ones. Researchers plan to first study the mountainous region that abuts Minamisoma city, which is located about 25 kilometers, or 16 miles, from the Fukushima Daiichi plant. The highland, sitting west to Minamisoma, which was made famous when the city mayor’s public appeal for help on YouTube in late March attracted hundreds of thousands of views, is a well-known home to dozens of wild monkey families. After tracking the monkeys for about one to two months, the researchers will recover the animals and collect the data.

Preliminary investigations were conducted in October and the team is seeking to implement the project as early as February. Mr. Takahashi envisions that the study will run for at least five to 10 years, but hopes it will continue beyond that to thoroughly track the effects of cesium 137, which has a half-life of 30 years.

At first, two to three monkeys will be used, with more added later on and, further down the line, possibly wild boar too.