What relatively common issue may cause bloating in ruminants?

Bloating in ruminants is commonly caused by overfeeding with high concentrate diets. Ruminants, such as cattle and sheep, normally digest fibrous plant materials through a process involving fermentation in their rumen. When they are fed excessively high levels of concentrates like grains, it can lead to rapid fermentation and gas production, which may overwhelm the animal's ability to eructate (belch) the gas out. This accumulation of gas in the rumen leads to bloating, which can be a serious health issue.

Insufficient water intake does not directly lead to bloating but can affect overall digestion. Lack of veterinary care might contribute to undiagnosed health problems over time, while excessive exposure to sunlight does not have a specific connection to bloating in ruminants. Therefore, the direct relationship between high concentrate diets and the resulting fermentation makes this option the most relevant cause of bloating in ruminants.