Tag Archives: cow

Cows could help us in the plastic crisis — with the bacteria in their guts

Cows, which are a significant source of greenhouse gas emissions, could end up helping in another environmental crisis. According to a new study, the cow gut can digest certain types of plastic and offer a sustainable way of reducing plastic litter — not by having cows eat plastic, but by recreating the bacteria in a controlled environment.

Unlikely allies in our fight versus plastics. Image credits: Claudio Schwarz.

The stomachs of cows (like other ruminants) have four compartments, the largest of which is called the rumen. The rumen favors the development of a microbial community that is essential to the cows’ wellbeing. Cows can’t technically digest much of the food they eat, so instead, microbes in the rumen ferment the food and produce volatile fatty acids, which are the cows’ main source of energy.

Researchers suspected that these bacteria could disintegrate some plastics, because the cow diet already contains some natural plant polyesters.

“A huge microbial community lives in the rumen reticulum and is responsible for the digestion of food in the animals,” said Dr Doris Ribitsch, of the University of Natural Resources and Life Sciences in Vienna, “so we suspected that some biological activities could also be used for polyester hydrolysis,” a type of chemical reaction that results in decomposition.

The researchers tested how well cow rumen could degrade three types of plastic:

  • Polyethylene terephthalate (PET) — A very common and lightweight plastic found in many types of packaging (including water bottles);
  • Polybutylene adipate-co-terephthalate (PBAT) — A type of biodegradable plastic used to produce compostable plastics;
  • Polyethylene furanoate (PEF) — A plastic made from renewable materials that serves as an alternative to PET.

The bacteria inside the cow rumen was very good at breaking down all these types of plastics successfully and in a sustainable way. The results on PET are particularly exciting since it’s one of the most common plastics in the world, and it keeps accumulating in landfills and oceans. According to some estimates, the world is already producing over 500 billion PET bottles a year — and twice as much PET is used in synthetic fibers.

PET is notoriously hard to break down, and although the rumen microbes were less active in digesting PET than the other types of plastic, it could still offer a way to deal with this type of plastic. However, scaling the operation is still challenging. Researchers suggest that rumen material from slaughterhouses could be used for this purpose with relative ease.

Ideally though, the cow gut system could be recreated in a controlled environment and scaled up significantly. While this type of research can be very expensive, Ribitsch is looking forward to further research on the topic, emphasizing that microbial communities are underexplored as a potential eco-friendly resource.

The study has been published in the journal Frontiers in Bioengineering and Biotechnology.

Wild cows swept away by Hurricane Dorian found miles away on an island

The three castaways were found grazing peacefully on North Carolina’s Outer Banks, where they apparently washed up.

The skittish cows swam for miles and miles.

Hurricane Dorian was the most intense tropical cyclone on record to strike the Bahamas, and it also viciously struck mainland US. The National Centers for Environmental Information estimated total damage in the United States to be in excess of $1.2 billion. Houses were destroyed, towns were flooded, and there were a few fatalities. Among all this mayhem, animals are often unsung victims.

This is the case of a a wild herd of cows affectionately known as the “Sea Cows.” The 20 or so animals part of the Sea Cows normally live on private land, where they normally graze and mind their own business. Unfortunately for them, they were swept by the powerful hurricane, and only three appear to have survived. These three, however, appear unscathed — and they must have swum for miles to safely get to the island.

It’s a wild adventure and no doubt, if these cows could speak, they’d have a hell of a story to tell.


Cape Lookout National Seashore officials think the stranded cows swam up to 5 miles (8 kilometers) during the September storm. Cows can swim, but they’re not particularly good at it. It’s tremendous that they made it, and it shows that cows can be surprisingly resilient if given the chance.

It wasn’t easy to get them back home. National Park Service officials said the cows are “very wild and very skittish” and apt to run if approached by humans. In the end, however, they were returned to their home — which as you can imagine, made them really happy.

“That they were happy to be home was evident as they kicked up their heels and ran down the beach once they were released on their former range on Cedar Island,” Cape Lookout National Seashore said on Facebook.

“It took a lot of folks coming together to make this happen, and we are happy the cows made it home to Cedar Island,” Cape Lookout National Seashore Superintendent Jeff West said in the park’s announcement. “I am pretty sure they are too!”

It’s a bittersweet story, a reminder that animals are also victims of extreme weather — and that sometimes, they can survive even in the toughest of conditions.

This small change could cut halve your diet’s environmental impact

A simple change could massively reduce the negative impact of most people’s diets: swapping beef for poultry.

Bottom line: don’t eat this guy.

It doesn’t often make the headlines, but food production is one of the major culprits of climate change, contributing up to 29% of total greenhouse gas emissions. Out of this, meat takes an overwhelming slice of the pie.

At a basic level, it’s easy to understand why meat is so inefficient: plants convert around 10% of the energy they receive into edible nutrients. Animals have a similar rate: only about 10% of the plants they eat are converted into something we can eat, so 90% of the energy is wasted (arguably, some of that energy comes from plants we ourselves couldn’t eat, but even so, it’s a wasteful process).

Over 50% of all the emissions associated with food comes from meat production and consumption, although meat itself provides less than 10% of the calories we eat. Beef, in particular, is extremely inefficient.

A beef with the environment

It takes 75 times more energy to produce a pound of beef than to produce a pound of corn, and beef also requires 54 calories of fuel to produce 1 calorie of protein, compared to 2-3 calories of fossil fuel for 1 calorie of soy or wheat. Study after study has shown that beef is an important contributor to global greenhouse gas emissions — and this one is no different. In the latest research, scientists show that even by replacing beef with other meat (poultry) it could make a big difference.

Diego Rose, a director of nutrition at Tulane University, analyzed what would happen if people would substitute a beef-focused meal with a similar poultry meal. Along with his colleagues, he analyzed the diet information from more than 16,000 participants in the 2005-2010 National Health and Nutrition Examination Survey, calculating a carbon footprint of all diets.

They found that the 10 foods with the highest impacts on the environment were all cuts of beef.

Then, they looked at what would happen if all beef in the diets would be replaced by an equivalent poultry dish. For instance, broiled beef steak was replaced with broiled chicken and ground beef with ground turkey. The results were impressive.

“Our simulation showed that you don’t have to give up animal products to improve your carbon footprint,” Rose commented on the study. “Just one food substitution brought close to a 50% reduction, on average, in a person’s carbon footprint.”

That’s how disproportionate beef’s carbon footprint is — even replacing it for something that’s not exactly eco-friendly either has a massive impact. Of course, any further reduction of meat consumption has even more environmental benefits. Researchers also stress that food waste and overeating also increase the carbon footprint of our diet.

The results have not yet been peer-reviewed but have been presented at the Nutrition 2019 conference, where they have been selected by a panel of experts.




Humanity is just 0.01% of all life but we wiped out 83% of all wild mammals


About 60% of all mammals on Earth are livestock. Credit: Pixabay.

With our fragile appearance, humans don’t look like much at first glance. Our impact on the planet, however, is unrivaled and unfortunately mostly negative. It is a proven scientific fact that even the climate is changing in response to human activity — that’s how consequential our actions are. Our huge infrastructure works have carved huge gaping holes inside mountains or even beneath the ocean. And, according to a new study, we’ve culled most of the planet’s wild animals and plants, replacing them with our livestock and crops.

The world’s 7.6 billion people represent only 0.01% of all living things, according to researchers at the Weizmann Institute of Science in Israel. However, our impact on nature is disproportionately huge. After Ron Milo and colleagues in Israel estimated all of the different components of biomass, they eventually calculated that humans have caused the loss of 83% of all wild mammals and half of all plants.

For three years, Milo and his team had been combing through the scientific literature in an attempt to estimate the total mass of all life forms on Earth. To simplify things, the researchers looked at carbon content, ignoring other aspects — like water content — that might have made comparisons between various life forms difficult. The tally shows that the planet’s total biomass weighs 550 gigatonnes of carbon. Considering their amount of carbon, Earth’s life forms can be ranked as follows:

  • bacteria 13%;
  • plants 82%;
  • all other creatures, from marine life to insects, 5%;

By carbon content, fungi (12 Gt C) are about six times more abundant than all animal life on the planet (2 Gt C), whereas the biomass of humans represents just a tiny fraction of that (0.06 Gt C). However, humanity’s biomass can grow to gargantuan proportions if you factor in our food: livestock. The researchers estimate that of all birds on the planet, 70% are farmed poultry, with just 30% being wild. For mammals, the picture is even grimmer: 60% of all mammals on Earth are livestock, mostly cattle and pigs, 36% are the humans themselves, and a mere 4% are wild mammals.

Five-sixths of wild land animals have been lost since the industrial revolution began, over than a century and a half ago. Meanwhile, in the oceans, three centuries of whaling and aggressive fishing have reduced marine mammals to a fifth of what they were.

“It is pretty staggering,” said Milo. “In wildlife films, we see flocks of birds, of every kind, in vast amounts, and then when we did the analysis we found there are [far] more domesticated birds.

”The destruction of wild habitat for farming, logging and development has resulted in the start of what many scientists consider the sixth mass extinction of life to occur in the Earth’s four billion year history. About half the Earth’s animals are thought to have been lost in the last 50 years.”

The results suggest that there has never before been a species that comes close to Homo sapiens, one that has caused the destruction of so many other species and individuals. In fact, our propensity to alter the environment and replace wildlife has some scientists claiming that we’re actually living in a new geological era called the Anthropocene.

“It is definitely striking, our disproportionate place on Earth,” said Milo. “When I do a puzzle with my daughters, there is usually an elephant next to a giraffe next to a rhino. But if I was trying to give them a more realistic sense of the world, it would be a cow next to a cow next to a cow and then a chicken.”

This study published in the Proceedings of the National Academy of Sciences goes to show that far from being puny mortals, we humans have become a huge driving force that’s capable of destroying hundreds of species if we so wish it (or just don’t pay particular attention). Perhaps, one day, we’ll also learn how to harness this immense power with matching responsibility.

Ancient humans were practicing brain surgery on cows 5,400 years ago

Mankind has a long history of highly questionable medical practices, but out of them, trepanation (a surgical intervention in which a hole is drilled or scraped into the skull) definitely takes the prize.

The motivation to drill holes in other people’s skulls haunts me to no end, especially as the practice seems to have survived through the centuries and perhaps even for millennia. Now, scientists have discovered a cow skull that underwent trepanation, suggesting that early humans honed their skills on animals.

Image credits: Fernando Ramirez Rozzi.

It all started about a decade ago, when Fernando Ramírez Rozzi, a paleontologist focusing on human remains at the French National Center for Scientific Research, was approached by a colleague who asked him to examine a strange cow skull. The skull was excavated in France during the late 1970s, in Vendée — a Neolithic site believed to be a trade hub for salt and cattle between 3400 and 3000 B.C.E. The skull featured an unusual hole, which was initially chalked off as an injury from another animal.

But something just seemed off. Working with Alain Froment, an anthropologist at the Museum of Mankind in Paris, Rozzi used advanced imaging techniques to analyze the hole, finding that there was no evidence of blunt force trauma, and the hole is simply too clean to be caused by another animal. They also ruled out infection, cancer, erosion, and pretty much anything that might have caused the hole — anything, that is, except for the most likely scenario: humans.

The hole was similar to trepanation practices, so the authors conclude that the cow’s owners probably wanted to save it from some sort of brain disease. “As early as the Neolithic period, these kinds of symptoms were already linked to brain physiology,” the authors write. If this is indeed the case, then it might not have been such a bad idea — even to this day, in some cases, neurosurgeons treat excess swelling in the brain by removing a small part of the skull.

But this theory is quite a leap, and many questions still remain.

Enhanced viewing of the hole compared to those found in human skulls. Image credits: Fernando Ramirez Rozzi.

For starters, archaeologists have found the remains of hundreds of cows at this site, but only one with such a hole. If there was an epidemic, you’d expect to see more cows with similar holes, and generally, at the expected size of the herds, one cow would have been easily replaced. Another possibility is that the hole wasn’t made in a trepanation procedure, but rather during some sort of ritual. However, this theory is strongly combated by the fact that only one such hole has ever been found. Furthermore, authors write, it “would have had greater value, practical or symbolic, if performed on a human being rather than on a common animal.”

Instead, they believe that the cow was a test subject for someone who was preparing to carry out similar procedures on humans. Finding test subjects was tricky, as volunteers would, obviously, be scarce. Cadavers would be no good since they don’t react like the living organism, so an animal like a cow or a pig could have been quite useful. Interestingly, several pig skulls have been found in different site with similar holes, which might be an important piece of the puzzle.

Of course, it could also have a completely different that we’re all missing. This is always the big challenge when working in archaeology: you’re trying to draw as much as possible from incomplete information, and there are slim chances of ever finding confirmation. Whatever the case may be, the idea that that seven millennia ago someone was practicing brain surgery on cows is perplexing. But who knows — perhaps 7,000 years from now, future observers will look back on our medical practices and ask themselves, “Why on Earth did they do this?”

cow chewing

‘Chewing like a cow’ helped early mammals thrive in the wake of dinosaur extinction

We’re generally more interested in what’s on our plate than how we eat it, but here’s an interesting thought you can bring to the dinner table tonight. According to evolutionary biologists from the University of Chicago, the same side-to-side chewing motion that’s familiar across most mammals helped our early ancestors grind food with their molars and opened up access to a more diversified diet. This evolutionary edge may have gone a long way 66 million years ago, during the mass extinction event of the Cretaceous known for wiping out the dinosaurs.

cow chewing

Credit: Pixabay

You’ll often hear aviation engineers use the terms ‘pitch’ and ‘yaw’ to describe the movements of airplanes, where pitch rotation results in basic up and down movement while yaw rotation results in side-to-side, crosswise motion. The same terms are employed by the biologists as well, when talking about the mechanics of motion of various body parts. For instance, almost all modern mammals from deer to kangaroos to humans share similarities in their jaw and muscle structure that enable both pitch and yaw.

David Grossnickle, a graduate student at University of Chicago’s Committee on Evolutionary Biology, wanted to investigate how mammalian chewing evolved. He painstakingly combed through 2D photos of early mammal fossils and 3D data collected from modern mammal specimens by the Field Museum, and eventually spotted some patterns.

The analysis revealed mammal teeth, then their muscles, were increasingly adapting to allow yaw chewing. For instance, species began to develop projections on the upper molars that fit into the basin on the lower counterpart. The development caused changes in the musculature of the jaw which had to adapt to provide more torque required for side-to-side movements. Another important morphological change was around the ears, as a bony attachment between the middle ear elements and jaw became gradually lost.

Eventually, early mammals became able to grind food between the molars like a mortar and pestle instead of cutting it with simple up and down movements like a knife. The whole process can be traced back to as early as 160 million years ago.

“If you have a very specialized diet you’re more likely to perish during a mass extinction because you’re only eating one thing,” Grossnickle said in a statement. “But if you can eat just about anything and 90 percent of your food goes away, you can still live on scraps.”

Credit: Nature.

This adaptation in the jaws and teeth may have been key to the success of early mammals following the great dinosaur extinction. Like dinosaurs, mammals were hit hard by the nuclear-winter-like conditions left in the wake of the giant asteroid impact which hit Chicxulub, Mexico, but due to a combination of factors like small size and high breeding rates, the mammals were able to rebound. Diet and, equally important, chewing motion seem to have played a very important role as well.

“The continued presence of tribosphenic molars in many modern mammalian lineages provides strong evidence of its evolutionary importance. Thus, the concurrent evolutionary changes to jaws, molars, ears, and chewing cycles in early cladotherians may have been an especially significant event in mammalian evolution,” Grossnickle concludes in his paper.

Journal reference: David M. Grossnickle. The evolutionary origin of jaw yaw in mammals. Scientific Reports, 2017; 7: 45094 DOI: 10.1038/srep45094

A seaweed could help us curb greenhouse gas emissions – if we feed it to cows

It seems hard to believe, but something as simple as feeding seaweed to cows could make a big difference in fighting climate change, essentially reducing yearly CO2 emissions by a whopping 3 Gt. For comparison, the entire European Union produces 3.4 Gt yearly.

According to Mr Kinley, the agriculture industry stands to be one of the first industries to make a dramatic reduction to greenhouse gas emissions if this research gets to market. Image credits: Rob Kinley.

Seaweed and cows

It may seem hard to believe, but livestock emissions represent 14.5 percent of all, global, anthropogenic greenhouse gas emissions. That’s a whopping 7.1 Gigatonnes of Co2-equivalent every year and even more than what the US emits yearly (5.334 Gt CO2/year). But for all the talk we have about curbing emissions, there’s not much talk about livestock.

Professor of aquaculture at James Cook University in Townsville, Rocky De Nys, may have a good idea on how to reduce those emissions. He found that adding a small quantity of dried seaweed to a cow’s diet can reduce the amount of methane a cow produces by up to 99 per cent.

“We started with 20 species [of seaweed] and we very quickly narrowed that down to one really stand out species of red seaweed,” Professor De Nys said.

Cows output a lot of methane into the atmosphere, and methane, while short-lived, is a much more potent greenhouse gas than carbon dioxide. Contrary to popular belief, most of the methane comes out through burping and not on the other end of the cow. This happens because the plants they munch up ferment in their stomach, creature pressure and then… are released from the cow. This is where the seaweed comes in, inhibiting methane formation.

You don’t need a lot of it, just a bit sprinkled on top of their diet.

“When the seaweed is harvested it is dried, and it can be added as a sprinkle essentially to the diet, just as you would add a mixture of herbs and spices to the chicken,” he said.

This species could help us curve our greenhouse gas emissions. Image credits: Jean-Pascal Quod

The species is called Asparagopsis taxiformis, a type of red algae. The researchers have only created artificial “cow stomachs,” in which they simulated the real thing, but these results are very promising. Furthermore, they do have some practical results on other species.

“We have results already with whole sheep; we know that if asparagopsis is fed to sheep at 2 per cent of their diet, they produce between 50 and 70 percent less methane over a 72-day period continuously, so there is already a well-established precedent.”

Making a difference

So could this actually make a difference? Research scientist with Agriculture and CSIRO, Rob Kinley, who was heavily involved in the research project believes the answer is ‘yes’.

“All sectors are trying to be responsible and reduce their contribution to climate change, which in many instances relates to reducing their contributions to greenhouse gas emissions,” he said. “Agriculture stands to be one of the first to make dramatic reductions if we can get this to market.”

But there is another issue: that of quantity. As De Nys says, you don’t need a whole lot of seaweed, just some sprinkled on top. But when you consider the sheer size of the livestock industry, that’s still a huge amount. It’s so large that harvesting simply isn’t an option, so we need to develop another industry of seaweed growing.

“Wild harvesting isn’t going to do it because it’s far too expensive and the recourses aren’t enough, so we need to get partners on board who can produce the seaweed in a cultivation process. Whether that be in South-East Asia where they are already farming millions of tonnes of seaweed, or beginning a new industry somewhere through the southern or western side of Australia.”

This would, in turn, generate some emissions in itself, eliminating some of the benefits. But Kinley says this investment is definitely worth it – and it’s only a matter of ‘when’ – not a matter of ‘if’.

“Money will decide how quickly we can move … the sooner we have more money to move forward with the research, the sooner we will be able to get it out,” he said. “Three years isn’t outside the realm if we can get enough support to move with it.”

Personally, I’d like to a see a broad lifecycle analysis (including the seaweed production, transport and distribution) before we start implementing, but if the results stand up then there’s a lot of promise. I do believe that agriculture, especially on its animal side, should be addressed much more strongly.

Still, it should be kept in mind that this only reduces some of the emissions from the livestock. Meat is one of the most non-eco-friendy food sources available – especially livestock and pig farming. Reducing global meat consumption is still essential for a sustainable future – even if we do start feeding cows seaweed.