True "bloat" is a condition of ruminant animals, common in barley fed fattening cattle, or those fed tubers such as potatoes and turnips. It is also possible in sheep and goats, again usually those on high concentrates, fattening lambs or kidding/lactating goats, or anyone that breaks into a feed store!
Either the rumen conditions change, allowing a foam to build and trap rumen gases (as in acidosis from too much grain or concentrates) or a physical blockage such as a potato stops belching and release of rumen gases.
Symptoms are being off food, sometimes dull and a very large tummy behind the ribs, more so on the left, which is taut and gas filled.
It can be fatal rapidly when the pressure of the rumen stops blood returning to the heart, post mortem can sometimes show this is the case.
Treatment requires getting the gas out, either by passing a stomach tube or putting a cannula in the animal's side. If mild, repeated treatment with bicarbonate of soda to dilute the excess acid, and vegetable oil to help break up the foam, can be successful. This is more likely to be helpful in small ruminants as cattle can produce such vast volumes of gas it is more likely to be fatal if not treated rapidly as above.
In young lambs (and other ruminant species) the rumen is not yet developed and so the gases produced are usually due to milk getting into the undeveloped rumen instead of the abomasum or true stomach. The true stomach is acidic, so the correct bacteria and conditions exist to digest milk. The rumen is not acidic, and at this age, does not have many digestion bacteria, so Lactobacilli feed on the milk and grow rapidly, as can other species like E. coli. These bacteria can produce gases, allow the milk to ferment and become like curds, blocking up the flow of intestinal content and onwards to faeces.
This will result in full, bloated tummies, but often with sloshing sounds if the animal is gently rattled, as in the name "watery belly" where the gas and liquids in the stomachs mix.
It is also commonly known as "bloat" in bottle lambs, or I believe "floppy kid syndrome" is similar, and is often due to kids or lambs guzzling excess bottle milk and overfilling the true stomach causing the situation above.
Treatment for this is antibiotics to kill E. coli in particular, rehydration fluids instead of milk for at least 24 hours, little and often as the stomachs is already full.
The best chance of recovery is if attention is paid to the gut transit element - warm water and washing up liquid can be given as an enema. The water will be absorbed to an extent, aiding with hydration, and the liquid and soap will help break down the sticky faeces, fermented milk and general sticky obstruction in the intestines.
