Ruminal bacteria

Methane is a greenhouse gas. It comes largely from methanogenic bacteria, ruminant animals, and the activities of man. 

Ingested plant metabolites, drugs and other compounds are processed both by the animal and by the microbial flora of the gut. The composition and activities of the gut microflora vary greatly from one animal species to another and have been very extensively reviewed." In true ruminants (sheep, cattle and deer) and in functional ruminants, such as camels and llamas, a mixed population of bacteria,... 

Wattiaux, M.A. and Reed, J.D. 1995 Fractionation of nitrogen isotopes by mixed ruminal bacteria. Journa/ of Animal Science 73 257-266. 

Animals (ruminants) Carbon from cellulose (bacteria)... 

Some of the unsaturated fats ingested by ruminants are partially hydrogenated by bacteria in the rumen. In consequence, milk fat, dairy products, as well as beef and mutton fat, also contain small amounts of trans isomers, about 2 to 9%. However, in fat from ruminants the main trans fatty acid is vaccenic (18 1 t 11), while in hydrogenated fats it is elaidic (18 1 t 9) (Figure 13.14). 

In ruminants, lactic and propionic acids are the major precursors of glucose. This is particularly important during lactation, since all the carbohydrate in die food is fermented by die bacteria in the rumen, so diat no glucose enters the body but glucose is required for die formation of lactose for the milk (Chapter 6). 

Ruminant bacteria produce some trans -unsaturated fatty acids when long-chain fatty acids are synthesised in the bacteria. These are absorbed by the host so that trans-unsaturated fatty acids can be found in adipose tissue and muscle of ruminants. 

Saprophytic anaerobic bacteria, e.g. the ruminant bacterium Lachnospira multiparus and the methane digestor isolate, Clostridium populeti, secrete only acidic pectate lyases that exhibit an exolytic/endolytic depolymerization toward polygalacturonate. It will be important to determine if this acidic property contributes to the adsorption of these enzymes to the secreting bacterium, perhaps contributing to the efficiency with which the bacteria are able to assimilate the products generated by these enzymes. 

Cellulose differs from amylose principally in the stereochemistry of the acetal linkages, which are a in amylose but P in cellulose. a-Amylase is specific for al 4 bonds and is not able to hydrolyse pi 4 bonds. An alternative enzyme, termed cellulase, is required. Animals do not possess cellulase enzymes, and thus cannot digest wood and vegetable fibres that are predominantly composed of cellulose. Ruminants, such as cattle, are equipped to carry out cellulose hydrolysis, though this is dependent upon cellulase-producing bacteria in their digestive tracts. 

Our linguistic abilities aren t innate. They are not encoded in our DNA. Language is more like E. coli, the bacteria in our gut, symbiotically helping us to digest our food. Language helps us digest phenomena, allowing us to ruminate on the nature of the world. ... 

Treatment cf these disease states may be based on vaccination or drugs. In some cases, e.g. swine dysentery, no vaccines are available, so antibiotic treatment is essential. Antibiotic administration may be prophylactic or therapeutic with pigs, in particular, agents to control dysentery are routinely added to feedstuff or drinking water. The route of administration may also be highly important. For instance, in ruminants the preferred mode is injection, e.g. parenterally. The oral route, which introduces antibiotics directly into the rumen, may upset the delicate balance of rumen bacteria which are necessary to ferment carbohydrates to fatty acids — an essential component of the energy supply of ruminants. 

The FDA first approved use of a polyether ionophore as a feed additive for cattle in 1975. Ionophores were first isolated from bacteria generally of the S treptomyces genus, but are produced commercially by bacterial fermentation (qv). Monensin [17090-79-8] and other ionophores are being fed to over 90% of feedlot catde grown for beef (53) to enhance efficiency of gain improvements of 5—10% are common. Ionophores also are used as anticoccidial dmgs in poultry production and have similar, but lesser, effects in ruminants (54). 

The human body contains only about 1.5 mg of cobalt, almost all of it is in the form of cobalamin, vitamin B12. Ruminant animals, such as cattle and sheep, have a relatively high nutritional need for cobalt and in regions with a low soil cobalt content, such as Australia, cobalt deficiency in these animals is a serious problem. This need for cobalt largely reflects the high requirement of the microorganisms of the rumen (paunch) for vitamin B12. All bacteria require vitamin B12 but not all are able to synthesize it. For example, E. coli lacks one enzyme in the biosynthetic... 

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