Energy and mineral nutrition and water intake in the captive Indian rhinoceros (Rhinoceros unicornis)

Abstract

In the captive Indian rhinoceros (Rhinoceros unicornis), two disease complexes with a high incidence-chronic foot problems and uterine leiomyomas-may be linked to excess body weight (BW). In this study, intake and digestion trials were conducted (by means of 7-day weigh-backs, and 5-day total fecal collections, respectively) with I I Indian rhinoceroses at four zoological institutions in Europe and the United States to quantify energy and mineral nutrition on conventional or roughage-only diets. Diets comprising a variety of forages (grass hay only, a combination of grass hay and grass silage, straw, or a mixture of grass and legume hay) were offered as the roughage source, along with various concentrates, produce, and supplements. Water intake was quantified, and urine samples were obtained opportunistically. The animals consumed 0.5-1.1% of their BW in dry matter (DM) daily, with calculated digestible energy (DE, in megajoules MJ) values ranging from 0.27 to 0.99 MJ DE/kg BW0.75/day compared to an estimated requirement of 0.49-0.66 MJ DE/kg BW0.75/day. Seven of 11 rhinos (64%) fed restricted levels of concentrate plus forage consumed DE in excess of this estimate. Even on roughage-only diets, some individuals consumed energy well above the presumed metabolic requirements. Hence, restriction of both concentrates and roughage may be important for weight management in this species. Water intake ranged from 30 to 49 mL/kg BW daily (3.4-5.2 L/kg ingested DM), similar to values that have been reported for domestic equids. Excretion amounts and patterns also resembled those found in horses. Endogenous fecal losses measured for Ca, P, Cu, Fe, and Zn indicate that the maintenance requirements of these minerals should be met in Indian rhinoceroses by diets that meet recommendations for domestic horses. It is particularly important to evaluate dietary adequacy in mineral nutrition in this species in concert with the need for restricted energy intake, especially with regard to the hypothetical involvement of a low Zn supply in chronic foot problems

Feed consumption, diet digestibility and mineral utilization in captive blackbuck (Antelope cervicapra) fed different levels of concentrates

“…Concentrate feeds usually contain more available P as compared to roughages feeds (Clauss et al., 2005). As a result, intake of P was higher on rations with concentrates.…”

“…In addition, concentrate supplementation may improve the supply of minerals which otherwise deficient in forage‐based diets. Mineral deficiency/imbalances have been widely reported in livestock and wild animals (Clauss et al., 2005; Sharma and Joshi, 2005). However, excessive feeding of concentrates may adversely affect rumen function leading to acidosis and may also cause obesity (Clauss et al., 2005) and imbalance/excess of one or more minerals.…”

Influence of work on nutrient utilisation in semicaptive Asian elephants (Elephas maximus)

“…Energy requirement of elephant is not known. However, based on review of literature (Meyer & Coenen 2002;Clauss et al 2005), DE requirements have been set at 144 kcal DE/kg BW 0.75 for maintenance, beyond which obesity was suspected. Further, 1.25 times maintenance DE has been recommended for working horses (NRC 1989).…”

Digestive Efficiencies of Ex Situ and In Situ West Indian Manatees (Trichechus manatus latirostris)

“…Linking these to published energy densities of potential foodstuffs, the amount of food necessary to meet these requirements can be estimated. In the absence of measured values for either urinary energy losses or methane production and the apparent lack of a heat increment of feeding (Gallivan and Best 1986), ME was assumed to be 90% of digestible energy (Robbins 1993;Clauss et al 2005). Standard metabolic rate (SMR) was calculated using the Kleiber (1975) equation (SMR p 3.4 mass 0.75 ) and converting to megajoules per day.…”