January 28, 2009, 6:22 AM CT

Names give cows a lotta bottle

A cow with a name produces more milk than one without, researchers at Newcastle University have found.

Drs Catherine Douglas and Peter Rowlinson have shown that by giving a cow a name and treating her as an individual, farmers can increase their annual milk yield by almost 500 pints.

The study, published online today in the academic journal Anthrozoos, observed that on farms where each cow was called by her name the overall milk yield was higher than on farms where the cattle were herded as a group.

"Just as people respond better to the personal touch, cows also feel happier and more relaxed if they are given a bit more one-to-one attention," explains Dr Douglas, who works in the School of Agriculture, Food and Rural Development at Newcastle University.

"What our study shows is what a number of good, caring farmers have long since believed.

"By placing more importance on the individual, such as calling a cow by her name or interacting with the animal more as it grows up, we can not only improve the animal's welfare and her perception of humans, but also increase milk production".

Dairy farmer Dennis Gibb, who co-owns Eachwick Red House Farm outside Newcastle, Northern England, with his brother Richard, says he believes treating every cow as an individual is "vitally important"......... Posted by: Kelly      Read more         Source

January 23, 2009, 6:24 AM CT

Spitting cobras hit their mark

Spitting cobras have an exceptional ability to spray venom into eyes of potential attackers. A newly released study published in Physiological and Biochemical Zoology reveals how these snakes maximize their chances of hitting the target.

The name "spitting cobra" is a bit of a misnomer. Cobras don't actually "spit" venom, says the study's main author Bruce Young, director of the Anatomical Laboratory in the Department of Physical Therapy at the University of Massachusetts, Lowell. Muscle contractions squeeze the cobra's venom gland, forcing venom to stream out of the snake's fangs. The muscles can produce enough pressure to spray venom up to six feet.

There are no points for distance, however. To be effective, venom must make contact with an attacker's eyes, where it causes severe pain and possibly blindness. Prior studies have observed that cobras hit their targets with alarming frequencynearly 100 percent accuracy from 60 centimeters.

Dr. Young and colleagues, Melissa Boetig and Dr. Guido Westhoff, have found the secret to the cobra's success.

Cobra venom does not hit a victim in one spot. Instead, the venom lands in complex geometric patterns. This is no accident, as per the study. The patterns are actively produced by the cobra......... Posted by: Kelly      Read more         Source

January 23, 2009, 6:12 AM CT

Just Living With Females alone

Living with a female mouse can extend the reproductive life of a male mouse by as much as 20 percent, as per a research studyconducted by Ralph Brinster and a team of other scientists at the University of Pennsylvania School of Veterinary Medicine. The study was reported online today in the journal Biology of Reproduction.

The scientists hypothesize that the females' effect on the environment of the spermatogonial stem cells likely occurs through the male's endocrine and nervous systems, but other systems are likely involved. The change amounts to a reduction of fertility six months earlier in "lonely" mice as opposed to those who have female companionship.

The results have significant implications for the maintenance of male fertility in wildlife, livestock and even human populations.

Brinster and his team housed male mice with and without female companions for 16-32 months. Each male was placed with two novel females at two-month intervals to test its ability to impregnate the females. The results indicated that males housed with females did not show a drop in fertility until 32 months of age, a six-month increase in fertility over males housed alone.

The study also indicated, however, that once male fertility began to decrease, the rate of decrease was the same for both those that lived with females and those that did not. The decline in fertility appeared to be due in part to defects in the sperm-production process......... Posted by: Kelly      Read more         Source

January 21, 2009, 9:36 PM CT

Listening to the songs of birds

We readily understand "Hello, how are you?" whether the question is posed in a small child's squeaky soprano or large man's booming bass. One way our brain enables this feat is by grouping continuous series of sounds into discrete categories, such as the syllables of a conversation. Despite the central importance of this perceptual process to vocal communication, the underlying brain mechanisms remain largely unknown. Researchers at Duke University Medical Center, recording brain activity in wild swamp sparrows listening to the songs of other birds, now have identified neurons likely to underlie categorical perception of vocalizations.

"The sparrow relies on categorical perception to recognize the songs of other sparrows and thus presents an excellent opportunity to understand how the brain enables categorical perception of vocalizations," says Richard Mooney of the Duke Department of Neurobiology, senior author of the study in Nature Neuroscience would be published online Jan. 11.

Previous studies showed that sparrows use categorical perception to rapidly recognize other sparrows' songs, reacting differently to a song as when the duration of a certain note in that song exceeds a "magical" perceptual boundary.

Using a miniature recording device, Dr. Jon Prather, a postdoctoral fellow in Mooney's lab and the first author of the study, recorded neural activity in a region of the sparrow's brain important to singing, and played subtly different songs to the bird through a nearby speaker. The results were surprisingly clear. The neurons responded briskly as long as the duration of a single note within the song was below a certain length, but not at all when the duration was increased beyond this boundary by even a few milliseconds......... Posted by: Kelly      Read more

January 20, 2009, 7:16 PM CT

How food choices influence California sea otters

Sea otters living along the central California coast risk higher exposure to disease-causing parasites as a consequence of the food they eat and where they feed.

Sea otters that eat small marine snails are at a higher risk of exposure to Toxoplasma gondii, a potentially deadly protozoal pathogen, than animals that feed exclusively on other prey, while sea otters living along the coast near San Simeon and Cambria are more at risk than sea otters that live outside this area.

Similarly, sea otters that usually feed on clams and fat innkeeper worms at the southern end of Monterey Bay have a higher exposure risk to another dangerous protozoal pathogen, Sarcocystis neurona Conversely, sea otters whose diet includes significant amounts of abalone, a preferred prey species when sufficiently abundant, have a very low risk of infection with either pathogen.

"Recovery of the sea otter in California has been particularly sluggish at the center portion of its range, where sea otter densities are highest and where most of the reproduction occurs," said Tim Tinker, a U.S. Geological Survey (USGS) sea otter expert at Santa Cruz, Calif., and co-lead of a newly released study led by the University of California-Davis and USGS. "Where food resources are limited, individual sea otters tend to become diet specialists, and the specific skills used to secure food are passed on from mother to pup"......... Posted by: Kelly      Read more         Source

January 20, 2009, 6:57 PM CT

Global warming, pollution and declining coral population

Coral reefs around the world are in serious trouble from pollution, over-fishing, climate change and more. The last thing they need is an infection. But that's exactly what yellow band disease (YBD) isa bacterial infection that sickens coral colonies. Scientists at the Woods Hole Oceanographic Institution (WHOI) and his colleagues have observed that YBD seems to be getting worse with global warming and announced that they've identified the bacteria responsible for the disease.

Just as a doctor can diagnose a child with chicken pox by the small, round bumps on her skin, you can tell a coral with yellow band disease (YBD) by its own characteristic markings. This affliction etches a swath of pale-yellow or white lesions along the surface of an infected coral colony. The discolored band is a mark of death, indicating where the bacterial infection has killed the coral's photosynthetic symbionts, called zooxanthellae. The coral host suffers from cellular damage and starves without its major energy source, and commonly does not recover.

In a paper reported in the November 2008 issue of the Journal of Applied Microbiology (JAM), main author James Cervino, a guest investigator in the WHOI Marine Chemistry and Geochemistry department, and colleagues report isolating the bacteria that cause YBD: a group of four new Vibrio species, which combine with existing Vibrio on the coral to attack the zooxanthellae. This is the first demonstration that the same bacterial culprits are to blame for the disease throughout the Caribbean as well as half way around the world in Indonesia......... Posted by: Janet      Read more         Source

January 15, 2009, 7:32 PM CT

Cooling the planet with crops

By carefully selecting which varieties of food crops to cultivate, much of Europe and North America could be cooled by up to 1C during the summer growing season, say scientists from the University of Bristol, UK. This is equivalent to an annual global cooling of over 0.1C, almost 20% of the total global temperature increase since the Industrial Revolution.

The growing of crops already produces a cooling of the climate because they reflect more sunlight back into space, compared with natural vegetation. Different varieties of the same crop vary significantly in their solar reflectivity (called 'albedo'), so selecting varieties that are more reflective will enhance this cooling effect. Since arable agriculture is a global industry, such cooling could be extensive.

Reporting today [15 January] in Current Biology, Dr Andy Ridgwell and his colleagues at the University of Bristol argue that we should select crop varieties in order to exert a control on the climate, in the same way that we currently cultivate specific varieties to maximize and fine-tune food production.

Dr Ridgwell said: "We have reviewed the effect of our approach in a global climate model. By choosing from among current crop varieties, our best estimate for how much reflectivity might be increased leads us to predict that summer-time temperatures could be reduced by more than 1C throughout much of central North America and mid-latitude Eurasia. Ultimately, further regional cooling of the climate could be made through selective breeding or genetic modification to optimise crop plant albedo"......... Posted by: Erica      Read more         Source

January 15, 2009, 7:31 PM CT

Plant flowering in different environments

It has been known for some time that plants respond to environmental cues that guide their flowering. Chief among these signals are light, temperature and vernalization, when flowering is promoted by prolonged exposure to cold temperatures.

In some plants, researchers have identified particular genes that deal with each of these environmental signals. But they haven't fully grasped how plants integrate these signals in nature. For example, when day length and temperature are combined in different ways, plants outdoors may not respond the same way as plants in the lab.

Through a series of field experiments at five European sites, a Brown University-led research team has charted the internal and external signals that guide the life cycle of one plant species, Arabidopsis thaliana, across its native climate range. The team has created a model that shows the importance of the genetic and environmental cues for key genotypes of Arabidopsis and how these signals vary depending on the plant's location and seasonal environment.

"This is a powerful tool to predict how this plant species and other species will respond to climate change and which genetic pathways are important in different environments," said Amity Wilczek, a postdoctoral research associate in ecology and evolutionary biology at Brown and the paper's main author......... Posted by: Erica      Read more         Source

January 15, 2009, 7:22 PM CT

Worldwide fish biomass and impact on climate change

Are there really plenty of fish in the sea? University of British Columbia fisheries researcher Villy Christensen gives the first-ever estimate of total fish biomass in our oceans: Two billion tonnes.

And fish play a previously unrecognized but significant role in mitigating climate change by maintaining the delicate pH balance of the oceans, as per a research studypublished in tomorrow's edition of the journal Science, co-authored by Christensen and a team of international scientists.

"By drinking salt water, fish ingest a lot of calcium, which needs to be removed or they will get renal stones," says Christensen, an associate professor in the UBC Fisheries Centre.

The team discovered that fish do this by binding the calcium to bicarbonate, and then excreting it as pellets of calcium carbonate, a chalk-like substance also known as "gut rocks," in a process completely separate from food digestion. For an animation of this process, visit www.publicaffairs.ubc.ca/download.

As the calcium carbonate from these pellets dissolves, it turns the seawater more alkaline, which has relevance for ocean acidification, and is impacted by the ocean's exchange of carbon dioxide (CO2) with the atmosphere.

To gauge the global impact of this process, Christensen and Simon Jennings from the UK's Centre for Environment, Fisheries and Aquaculture Science took two entirely different approaches to estimate the total biomass of fish in the world's ocean......... Posted by: Kelly      Read more         Source

January 15, 2009, 6:37 PM CT

The mystery of camouflage

At Hogwarts, Harry Potter uses an invisibility cloak to hide from his enemies. In nature, animals like cuttlefish and chameleons use the awe-inspiring tricks of camouflage to hide from theirs.

Roger Hanlon, a senior scientist at the Marine Biological Laboratory (MBL), has spent 35 years studying animal camouflage, and in that time he has moved beyond awe at nature's disappearing tricks and discovered three broad classes of camouflage body patterns. He and colleagues detail these three pattern classes, and how they achieve several mechanisms of visual deceit, in this week's issue of Philosophical Transactions of the Royal Society B The issue is entirely devoted to camouflage.

"Camouflage is found throughout the animal kingdom, among big, small, wet, and dry animals, but it is probably one of the least-studied natural phenomena we know of," Hanlon says.

This is one of the first efforts to quantify camouflage body patterns. "No one has successfully quantified, for instance, what is exactly meant by 'background matching,' which is when an animal visually blends into its environment," Hanlon says.

Eventhough Hanlon and his colleagues have begun to compare camouflage tactics in a number of animalslarge primates, amphibians, reptiles, fishes, insectsthis week's analysis focuses on the cephalopods, which include squid, octopus, and cuttlefish. Remarkably, these soft-bellied mollusks are able to dynamically produce all three classes of camouflage body patterns (termed uniform, mottled, and disruptive)......... Posted by: Kelly      Read more         Source