Sheaths also swell as a result of being dirty.. Horses with large beans (accumulations of secretions at the end of the penis) and large accumulations of sheath smegma (normal pasty secretion) often swell. Horses that urinate into their sheaths tend to have dirtier sheaths and more problems with swelling.
Some people think Alaska has less sunlight than other places. The opposite is true. Averaged over an entire year, Alaska gets 10-17 minutes more daylight per day than the rest of the country. If you include civil twilight, Alaska gets 40 minutes more light on average than the rest of the country.
Daylight in Iceland. From mid-May to mid-August the sun only sets for only a few hours each day, and it is effectively 24 hour daylight. This phenomenon creates a sort of lingering twilight into the early hours. In contrast, there are only around 4-5 hours of effective daylight during mid-winter.