Thus, while sulfates are laxative and may cause some diarrhea, their damage to the animal seems no greater than that of chlorides, and magnesium salts seem no more of a problem than calcium or sodium salts. Further, the effects of the various salts seem additive, which means that a mixture of them seems to cause the same degree of harm that a single salt does at the same total concentration. A number of observations have been made relative to saline livestock waters, some of them verified by experimental findings. At high salt concentrations that are somewhat less than toxic, increasing salinity may actually cause an increased water consumption, even when the animals refuse to drink for a short period of time at first. On the other hand, at very high salinities animals may refuse to drink for many days, followed by a period where they drink a large amount at one time and become suddenly sick or die.
Older animals are more resistant to harm from salinity than are the young.
Anything causing an increase in water consumption such as lactation, high air temperatures, or exertion also increases the danger of harm from saline waters. Animals seem to have the ability to adapt to saline water quite well, but abrupt changes from waters of low to waters of high salts concentrations may cause harm while gradual changes do not. Whenever an alternate source is available to them, even every two or three days, livestock will avoid excessively saline waters. And finally, when animals suffering from the effects of saline water are allowed water from a source of low salts content they make a rapid and complete recovery. Salt is sometimes used in feeds to regulate their intake.