Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New bulls may revive the Texas state Bison Herd

22.11.2004


The three young bulls donated by Ted Turner to be introduced into the Texas Bison Herd at the Caprock Canyon State Park. (Photo courtesy of Chester Hawkins, Texas Parks and Wildlife Department.)


It’s a match made in heaven. Or at least in the Texas Panhandle.

Three young bison bulls were donated by media tycoon Ted Turner from his New Mexico herd. They will be introduced into the Texas Bison Herd at the Caprock Canyon State Park next summer, in hopes they will provide much needed genetic diversity.

The Texas Bison Herd originated in the late 1800s with five bison calves captured by famed cattleman Charles Goodnight. The herd was donated to the state in 1997 and moved to the park. More information about the herd is available from http://www.tpwd.state.tx.us/expltx/eft/bison/ .



But even with intensive management by the Texas Parks and Wildlife Department that includes annual vaccinations, supplemental feeding and veterinary care, the herd has produced a small number of calves over the last six years. Possibly more troubling, the average age of approximately 40-animal herd has increased by three years, said Dr. James Derr, associate professor of veterinary pathobiology with the Texas A&M University College of Veterinary Medicine and the Texas Agricultural Experiment Station.

Derr and Dr. Natalie Halbert, a post doctoral research associate in the College of Veterinary Medicine, were asked to help. "If you have a healthy, stable population that’s having a reasonable number of offspring and the old ones are dying … the average age should not significantly increase over time," Derr said. "If the population is expanding and more babies are being born than old ones are dying, the average would actually decrease. "We, as geneticists, and the Texas Parks and Wildlife Department as wildlife managers, had a concern that something wasn’t going right. The managers were doing everything they could, and the herd was not increasing in size."

While sampling the DNA and doing pregnancy tests in the fall of 2001, Derr and Halbert found that 15 of the 18 adult females were pregnant. However, by spring, when the females were due to calve, only one calf survived. The rest were either not born or did not survive long after birth. Disease and genetic problems such as chromosomal defects were ruled out. But since Derr and Halbert already were sampling the DNA from the federal bison herds throughout the United States for another project, they knew how much genetic variation there should be in an "average" bison. "When we compared genetic variation in the Caprock Canyon bison herd, we found out they had significantly less genetic variation than any of the federal herds and most any of the other state and private herds," he said.

This led them to conclude the herd was suffering from inbreeding depression. Since the herd was confined on the Goodnight Ranch and then at the state park, no new genes had been brought into the herd in 120 years. With the assistance of Dr. William Grant, a professor of wildlife and fisheries science for the Experiment Station, Halbert developed and used computer models to simulate the future for the herd under best-case and worst-case scenarios.

She used genetic and demographic information such as the natality (birth) rate and death rate based on data from the last several years in the model and examined the data year by year. "The idea is to have an estimate, not a definite, of what would happen. In the future is the population going to be driven to extinction? Or is it likely to recover? Given the current problems with natality and mortality and the lack of variation at present, it’s most likely in the next 50 years the population is probably not going to survive," she said. One solution is to bring in new genetic diversity from an outside source. "But in this herd, it’s not something you do lightly," Derr said.

First of all, this herd, since it clearly originated in the Texas Panhandle, is probably the last genetic example of what was called the Southern Plains bison, said Danny Swepston of Canyon, Texas Parks and Wildlife Department wildlife district leader for the Panhandle. When the Transcontinental Railroad was built across the United States in the 1800s, the bison were split into what was known as the Northern and the Southern herds, with the latter made up of animals from Texas, eastern New Mexico, eastern Colorado, Kansas, Oklahoma and southern Nebraska. No other animals but those from Texas have been brought in. "What we didn’t want to do is bring animals in from outside," he said.

Also, the historical link to Goodnight made researchers reluctant to tamper with the herd too much, he said. Even though Goodnight donated three bulls to Yellowstone National Park before his death, animals could not be brought back from there because that herd is infected with brucellosis, a contagious bacterial disease, he said. "Our best option was to try and find a herd that that has a historical link to Texas bison, that did not have hybrids (of cattle and bison) or diseases that could be transmitted to this herd, and had a lot of genetic variation so that the animals we bring in can immediately bring in new genetics to help overcome inbreeding depression," Derr added.

They found that with Turner’s herd. "We tested that herd a few years ago, and we didn’t find any evidence of cattle mitochondrial DNA," a sure sign of cattle genetics in the herd. So last year, Texas Parks and Wildlife representatives, along with Texas A&M researchers traveled to New Mexico and chose three 1½-year-old bison bulls. "We picked the three handsomest, orneriest, teen-aged bulls that were in there," Derr said, laughing. The bulls arrived in January 2003 and have been placed in quarantine as a precaution against disease, Swepston said.

Texas Parks and Wildlife Department staff will keep them separated from rest of the animals until the cows are bred next summer. One or two of the young bulls will be put in with three or four cows, and samples of the DNA of the offspring will be collected. Swepston said it will be a long-term project. "It will be probably be a few years before we know the results." This type of work is important, not only to bison but other wildlife as well, Derr said. "The kind of genetic technology we’re using with North American bison ...was first developed for humans, and secondly used on livestock species such as cattle," he said.

Our hope is that when these studies are completed, they will form a model of the kinds of studies using genetic technology that can be used to preserve, conserve, and reconstruct many other wildlife species populations."

Two scientific articles explaining the details of this study in the Journal of Mammalogy and in Ecological Modelling were published this month.

Edith A. Chenault | EurekAlert!
Further information:
http://www.tpwd.state.tx.us/expltx/eft/bison/
http://www.tamu.edu

More articles from Agricultural and Forestry Science:

nachricht Filling intercropping info gap
16.11.2017 | American Society of Agronomy

nachricht Climate change, population growth may lead to open ocean aquaculture
05.10.2017 | Oregon State University

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>