ROLE OF MICROBES IN FOOD CHAIN
Over the last century many changes to methods of food production have taken place. Bacteria, microscopic in size, are vital participants in the process of food through the chain from soil to plants to the consuming animals and back to the soil. These tiny powerhouses break down organic materials by enzymatic digestion.
Over some decades of practice the changes in food production have had the effect of decreasing the populations of beneficial bacteria in our food supply and producing new strains of antibiotic-resistant bacteria.
Superbugs is the new way of describing bacteria that have naturally genetically modified in response to exposure to antibiotics. These superbugs are resistant to antibiotics so they cannot be eradicated with the plethora of drugs currently available. The attention and research in this area is increasing throughout the world. In its World Health Report 1996, the World Health Organization stated that "too few new drugs are being developed to replace those that have lost their effectiveness. In the race for supremacy, microbes are sprinting ahead.
That bacteria have adapted to the introduction of antibiotics into the food chain is not surprising. In its 'Oldest ever' fossils found report, the BBC News stated that "The oldest and tiniest fossils yet identified …..The bacterial creatures, which resemble "pond slime", were found in North West Australia and are estimated to be approximately three-and-a-half billion years old. Bacteria and algae like them are believed to have filled the primitive, super-heated oceans of the world during the earliest stages of life on this planet." Bacteria have successfully adapted to all manner of environmental changes and impacts. They have an immense capability to change.
Bacteria can acquire resistance genes through a few routes. Many inherit the genes from their forerunners. Other times, genetic mutations, which occur readily in bacteria, will spontaneously produce a new resistance trait or will strengthen an existing one. And frequently, bacteria will gain a defense against an antibiotic by taking up resistance genes from other bacterial cells in the vicinity. Indeed, the exchange of genes is so pervasive that the entire bacterial world can be thought of as one huge multicellular organism in which the cells interchange their genes with ease.
Changes that have affected bacteria in the human food chain:
Soil: Mass production of food has lead to short-cuts being adopted that leave out vital steps, in particular leaving pastures to rest with forage crops, legumes and animals. This slow composting of pastures returns organic matter and nutrients to the soil. Bacteria need dead organic matter to live and multiply and they travel through the food chain to us from the soil so if the soil is depleted this continues up the food chain.
Plants: In agriculture, antibiotics are applied as aerosols to acres of fruit trees, for controlling or preventing bacterial infections. High concentrations may kill all the bacteria on the trees at the time of spraying, but lingering antibiotic residues can encourage the growth of resistant bacteria that later colonize the fruit during processing and shipping. The aerosols also hit more than the targeted trees. They can be carried considerable distances to other trees and food plants, where they are too dilute to eliminate full-blown infections but are still capable of killing off sensitive bacteria and thus giving the edge to resistant versions. Here, again, resistant bacteria can make their way into people through the food chain, finding a home in the intestinal tract after the produce is eaten.
Livestock: The same drugs prescribed for human therapy are widely exploited in animal husbandry and agriculture. More than 40 percent of the antibiotics manufactured in the U.S. are given to animals. Some of that amount goes to treating or preventing infection, but the lion's share is mixed into feed to promote growth. In this last application, amounts too small to combat infection are delivered for weeks or months at a time. No one is entirely sure how the drugs support growth. Clearly, though, this long-term exposure to low doses is the perfect formula for selecting increasing numbers of resistant bacteria in the treated animals which may then pass the microbes to caretakers and, more broadly, to people who prepare and consume undercooked meat.
Humans: The western world's diet has increased in consumption of processed and devitalized food. The amount of sugar, fat, sodium, caffeine, preservatives, artificial colors and flavors in these foods encourages the growth of putrefactive organisms in the human digestive system. These types of foods put loads on the human system instead of providing nutrition. Modern medicines that kill non-resistant bacteria leave areas clear for resistant strains. People should also realize that although antibiotics are needed to control bacterial infections, they can have broad, undesirable effects on microbial ecology within the intestinal system and elsewhere. That is, they can produce long-lasting change in the kinds and proportions of bacteria and the mix of antibiotic-resistant and antibiotic-susceptible types not only in the treated individual but also in the environment and society at large.
Antibiotics in the Food Chain:
The widespread use of antibiotics has had far-reaching effects. Imagine a rich lawn of grass; there may be one or two weeds in it but they are not obvious and do not spoil the overall effect. Now imagine the same area after all of it has been sprayed with a herbicide designed to kill grasses indiscriminately. It is barren, but what happens next? Many weeds start to propagate over the entire area. Before the herbicide was applied the grass protected the area from the majority of unwanted weeds; without the grass weeds flourish. The same thing happens within our digestive system when we use antibiotics. Bacteria are wiped out indiscriminately leaving an environment for strong resistant bacteria to take over.
Back to the grassy area; if the area is replanted with grass and looked after the weeds will not take over, but it is a matter of using enough grass seed and regularly maintaining the area. If we do not repopulate our digestive system with beneficial bacteria and then maintain them, resistant bacteria can take over.
Multitudes of microorganisms inhabit our systems; all have a role to play somewhere. If they migrate to the wrong part of the system because that part has no competing bacteria they can then become a problem. Imagine our grassy area spreading its runners into a garden bed that has a lot of open, uncultivated areas; the grass itself becomes a weed. The same can happen with bacteria in our systems.
Candida albicans is a yeast normally found in the intestine. As long as the immune system is healthy Candida albicans is regulated and kept under control, it is considered a normal part of the intestinal flora. Many people who have a problem with Candida overgrowth in their system have histories of antibiotic use. Any imbalance in the populations of friendly bacteria provides an opportunity for other microorganisms to over-populate rampantly and infect other body organs and tissues. Candida albicans has been found in peoples' mouths when they are badly infected; its place is in the intestine.
Most bacteria help us. They work in our bodies, in the food chain, and in the decomposers of the world to maintain life. They are designed for specific roles and are a vital part of the world in which we live. They may well be the only solution to some of the ecological problems we face both within our systems and in the wider community. They are powerfully designed to do some great things.
Website References:
Alive...after 250 million years
Ancient bacteria trapped in a state of suspended animation for 250 million years are the world's oldest living things, claim US scientists.............
The Balance of Nature: Food Chains & Webs
Food Chains and Food Webs: In the living world, every form of life is food for another. Food chains and webs show how food and energy are passed between species................
Bats, Bacteria and Biotechnology
Microorganisms play a crucial role in maintaining the delicate ecological balance of the earth. They revitalize the soil by recycling the minerals and nutrients of decaying matter, and many are essential to the healthy growth of plants. Microorganisms also affect our lives more directly in the manufacture of such items as food products, detergents, antibiotics and antitumor drugs..............
Beginning with Bacteria
Microscopic in size, bacteria are the most numerous organisms in the compost pile. They are on all natural matter in the heap and reproduce at an amazing rate under the proper conditions. Their work initiates the activity of a succession of various organisms, each of which further breaks down complex materials to be utilized by its successor. These tiny powerhouses break down organic materials by enzymatic digestion, resulting in chemical oxidation that promotes their life processes..............
The cost of taking nature out of farming
As the wide door swings open, the nostril-clenching stench almost knocks you over. Sunlight slices through the windowless gloom, across a jostling carpet of chickens stretching from wall to wall............
A disaster in the making
High amounts of antibiotics in food chain signal major problems: WASHINGTON (IPS)—Contrary to previous estimates, the amounts of antibiotics used in animal agriculture dwarf those used in human medicine, warns a new report by a public interest organization. The high quantities of antibiotics used in the rearing of pigs, cows and chickens is significant, says the Union of Concerned Scientists (UCS), because of the growing specter of antibiotic-resistant disease................
Food Chain
We've all heard the term Food Chain. What follows is my interpretation of the Food Chain as regard the stock reductions in many (if not all) fisheries. Let's take a look at how it works:.....................
Looking for One of the World's Most Dangerous Toxin Bacteria
People in the United States are sickened by their food once a year, on average. But the food poisoning that suddenly appeared in White City, Ore., in December 1981 was something else. It was terrifying, and dramatic, and it seemed to have no cause. In the end, however, that mini-epidemic turned out to be the first show of force by a new strain of bacteria that is now infesting the food supply, infecting as many as 20,000 Americans a year and killing 500.......
'Oldest ever' fossils found
The oldest and tiniest fossils yet identified will be unveiled at a meeting in Strasbourg next week. The bacterial creatures, which resemble "pond slime", were found in North West Australia and are estimated to be approximately three-and-a-half billion years old..........
Powerful Bacteria
Many times when bacteria are mentioned, they are mentioned in a negative context. We are all aware that there are bacteria that can make us ill. An overwhelming percentage of bacteria is beneficial to us, however. Bacteria work within our bodies to do a number of good things. I can remember years ago, I was invited to visit the "germ-free" facility here in South Bend where germ-free animals are produced for certain kinds of research. I remember one of the workers at the lab complaining that they had a hard time getting rabbits to reproduce if there were no bacteria in their reproductive systems...........
Pollution Abatement & Reduction Council
As a commercial fisherman who has seen his industry transmogrified by our intrusive government from an individually based healthy way of life into profit centers for Government (via tarriffs), Corporations (via regulations) and Universities (via grants), I have come to the conclusion we have ALL been fighting the wrong battle, and not only the wrong battle, but one there is NO hope of ever winning. It's emotionally satisfying to be right, but we have all lost anyway and there's no changing that...............
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