Seasonal Energy Requirements and Water Intakes of Indian Crested Porcupines (Hystrix indica) in Captivity

Abstract

Four adult male Indian crested porcupines (Hystrix indica), held in covered outdoor enclosures in the Negev Desert of southern Israel, were offered ad lib. water and a dry rodent ration (16.5% protein; 9% fibre; 19.2 kJ/g dry matter) at four nutritional planes (100%, 80%, 60%, and 40% of ad lib. intake) during consecutive 10-day feeding trials in summer (July–August) and winter (January-February). Water intakes were significantly higher in summer (137 ± 61 ml kg−1 day−1X̄ ± SD) than winter (53 ± 7 ml kg−1 day−1). There were no seasonal differences in ad lib. food intake, in dry matter (DM) digestibility (annual X̄ = 76.5%), or in gross energy digestibility (80.9%). Moreover, maintenance energy requirements (estimated from body mass changes) were similar in both seasons, and averaged 220 kJ kg−1 day−1 (445 kJ kg−0.75 day−1), or 1.5 × estimated basal metabolic rate (BMR). These results, supported by limited data from free-ranging H. indica, indicate that Hystrix porcupines are capable of substantial formation and mobilization of fat reserves. This is a useful adaptation in seasonally fluctuating arid environments. Large inverse changes in the proportional composition of body water and body solids are likely such that total body mass is an inadequate index to body condition.