80% of antibiotics are being given to livestock animals:
>The proportion of antibiotics sold in the United States each year that go to animals turns out to be not 70 percent, but rather 80 percent. Here’s CLF’s Ralph Loglisci, who got the confirmatory numbers from the FDA.
And they also do it because it makes the animals gain weight:
>especially troubling is their use not to cure sick animals but to promote "feed efficiency," that is, to increase the animal's weight gain per unit of feed. These drugs are also regularly added to the feed and water of animals that are not sick in order to prevent diseases caused by overcrowded and unsanitary CAFO conditions. These nontherapeutic uses translate into relatively cheap meat prices at the grocery store.
Most of the antibiotics used for feed are ionophores and tetracyclines. Ionophones aren't used in humans but are only about 40% of the antibiotics used in feed. They are added to cattle feed because they cut down on illness caused by feeding grain (bloat is crazy, consider this a risky click: http://i.imgur.com/GfPvtBx.jpg ).
So most of the resistance concern would be with tetracyclines, where resistance is already a problem for many human infections.
The use of medically useful antibiotics as a feed additive should be stopped. I think it is harder to say that about ionophores.
In the third picture, the rumen has become pressurized from bloat, a condition they get when something stops them from belching (often the wrong sort of microbial activity in their rumen).
> I also wonder if all the antibiotics are making humans gain weight.
I'm wondering this too. Hopefully with the new research that's been happening with regards to gut flora we'll start to quantify how the amounts and type of bacteria affect digestive efficiency.
That's a pretty good bet. It works in cattle, and pigs (which are among the most closely related non-primates). And chickens. So maybe all vertebrates.
But I wonder whether there's more to it than "feed efficiency". Gut flora arguably changes nutrient mix before absorption. And some nutrients likely favor weight gain more than others. So perhaps one can recolonize with gut flora that favor overall health vs weight gain.
"The Good Gut: Taking Control of Your Weight, Your Mood, and Your Long-term Health"
Justin and Erica Sonnenburg are Stanford researchers that address almost all of this directly in the book with research they've done. Microbiome in the gut are directly impacted by antibiotics and in sterile mice studies those fed the exact same diets gain more weight after antibiotic treatments than those that aren't. As the Ars article makes a point of this is critical in a child's gut, stating that even single rounds of antibiotics can have negative impacts to the childs microbiome for years (side effects being weight gain comparative to other children, etc).
Just started to read the book as I've been interested in probiotics and gut health for a few years now and there just isn't much data out there. The researchers wrote the book from a new parent perspective which is makes the book relatable to those who have.
Keep in mind this isn't a book focused on attacking antibiotics, but the study of the microbiome in general and so antibiotics come into the picture of the book early (not finished with the book yet). Very good book so far otherwise.
Cooking meat means our immune system has fewer bacteria to kill off once the meat has entered our bloodstream, thus it's less work for the same calories. Would antibiotics have a similar impact?
There was a recent study where one group of mice were fed raw meat, and another were fed cooked meat. The cooked meat group gained weight while the raw meat group lost weight.
Cooking meat has much more to do with breaking down some of the less digestible parts of the food.
For example, http://www.ncbi.nlm.nih.gov/pubmed/17827047 says "For meat, cooking compromises the structural integrity of the tissue by gelatinizing the collagen. Hence, cooked meat should take less effort to digest compared to raw meat. Likewise, less energy would be expended digesting ground meat compared to intact meat. We tested these hypotheses by assessing how the cooking and/or grinding of meat influences the energy expended on its digestion, absorption, and assimilation (i.e., specific dynamic action, SDA) using the Burmese python, Python molurus."
That abstract concludes "We found cooking to decrease SDA by 12.7%, grinding to decrease SDA by 12.4%, and the combination of the two (cooking and grinding) to have an additive effect, decreasing SDA by 23.4%. These results support the hypothesis that the consumption of cooked meat provides an energetic benefit over the consumption of raw meat."
> Half the time the sweet potato or meat was presented raw, and half the time cooked; half the time it was also pounded and half the time unpounded. ... For both meat and sweet potato, Rachel found that when the food was cooked the mice gained more weight (or lost less weight) than when it was raw. Pounding had very little effect.
> We suspect that there are two major reasons for cooked beef providing more calories than raw beef. In cooked beef, the muscle proteins, like the sugars in cooked starch, have opened up and allowed digestive enzymes to attack their amino acid chains. Cooking also does this for collagen, a protein that makes meat difficult to chew because it forms the connective tissue wrapped around muscle fibers. However, we do not know the exact mechanisms.
Neither mention killing off bacteria, which makes sense as 1) meat doesn't enter the bloodstream but only its digestive products, and 2) stomach acids kill most of the bacteria.
> The positive energetic effects of cooking were found to be superior to the effects of pounding in both meat and starch-rich tubers, a conclusion further supported by food preferences in fasted animals. Our results indicate significant contributions from cooking to both modern and ancestral human energy budgets. They also illuminate a weakness in current food labeling practices, which systematically overestimate the caloric potential of poorly processed foods.
>The proportion of antibiotics sold in the United States each year that go to animals turns out to be not 70 percent, but rather 80 percent. Here’s CLF’s Ralph Loglisci, who got the confirmatory numbers from the FDA.
http://www.wired.com/2010/12/news-update-farm-animals-get-80...
And they also do it because it makes the animals gain weight:
>especially troubling is their use not to cure sick animals but to promote "feed efficiency," that is, to increase the animal's weight gain per unit of feed. These drugs are also regularly added to the feed and water of animals that are not sick in order to prevent diseases caused by overcrowded and unsanitary CAFO conditions. These nontherapeutic uses translate into relatively cheap meat prices at the grocery store.
http://www.ucsusa.org/food_and_agriculture/our-failing-food-...
I wish they'd save the antibiotics for humans so they'd be more effective. I also wonder if all the antibiotics are making humans gain weight.