Water consumption in small mammals (dwarf rabbits, Guinea pigs and chinchillas): New data about possible influencing factors.

Information on water requirement of small mammals is sparse and the assessment of daily water consumption is an important aspect of the veterinary practice in exotic pet nutrition. Water and feed daily intake are interlaced, that way the water to feed ratio is a meaningful indication. However, various factors such as ambient temperature or the uptake of substances to be eliminated via the kidney (i.e. calcium) must be taken into account when estimation of water consumption is carried out. Moreover, behavioural abnormalities could affect water consumption, like in the case of water uptake as a substitute action. Adequate water supply for small mammals is indispensable for health reasons (prophylaxis of urolithiasis) and consequences relevant to animal welfare. For this purpose, data from different trials enrolling no. 5 Flemish Belgian (FB) and no. 5 New Zealand White (NZW) rabbits, no. 10 dwarf rabbits, no. 7 guinea pigs and no. 7 chinchilla, were obtained to assess water intake according to feed rationing. Water balance following feed rationing was seen to differ across the species of small mammals considered in these trials. The comparative approach pointed to species-dependent water intake behaviour. Due to the species-related high variation in water uptake, it is not possible to give general recommendations for water supply of small mammals. In addition, water uptake is also influenced by the water content of the food, absolute dry matter uptake and food composition. Nevertheless, an additional supply of drinking water is recommended for all species, since unsatisfactory water supply reduces dry matter intake and may lead to energy undersupply.