Effect of concentrates restriction on feed consumption, diet digestibility, and nitrogen utilization in captive Asian elephants (Elephas maximus)

Abstract

In order to study the effect of concentrates restriction on feed consumption, diet digestibility, and utilization of nitrogen in captive Asian elephants (Elephas maximus), two feeding trials were conducted on three juveniles, four sub-adults, and three adults. During trial I, the conventional zoo diets of juveniles, sub-adults, and adult contained 22, 17, and 16% of concentrates on dry matter (DM) basis, respectively. During trial II, the amount of concentrate was reduced by 50%. A digestion trial of five days collection period was conducted during each period. The animals ate more roughages when concentrates were restricted. Intake of DM (g/kg BW(0.75) /day) was highest in sub-adults, followed by juveniles and adults. Apparent digestibility of crude protein (CP), neutral detergent soluble (NDS), and supply of digestible energy (DE) was highest in juveniles, followed by sub-adults and adults. Based upon the estimated metabolic fecal nitrogen (MFN) and calculated endogenous urinary nitrogen (EUN) and dermal losses, minimum dietary CP required to meet maintenance requirement was estimated to be 6.12, 6.05, and 5.97% in juveniles, sub-adults, and adults, respectively. Restriction of concentrates resulted in decreased (P < 0.05) digestibility of DM and GE, but the diet still supplied adequate amounts of DE and CP to fulfill estimated requirements of energy and protein during the period of experimentation. Thus, the concentrates portion of the diets of captive Asian elephants should be fed in a restricted way so as to reduce the intake of excessive calories and the potential risk of obesity.

Utilization of macro‐nutrients and minerals in captive greater one‐horned rhinoceros fed season‐specific diets

“…As the obligatory endogenous losses in the form of MFN remain constant, increasing the CP content of the diet results in increased apparent digestibility of CP. This corroborates well with findings reported earlier in greater one‐horned rhinoceros (Clauss, Froeschle, et al., 2005) and Asian elephants (Das et al., 2015). For optimal microbial activity, fibrinolytic organisms need a regular supply of degradable N, peptides, essential minerals and vitamins (Leng, 1990).…”

Feeding Asian pangolins: An assessment of current diets fed in institutions worldwide

“…We weighed the total amount of food given to each pangolin, as well as the amount of uneaten food. We adjusted the amounts of uneaten food for desiccation (as described in Das et al, ) and subtracted from the amount offered to result in a food ingested value. If we were unable to weigh any animals during the study period, we used their most recent weights provided by the institution.…”

Zoo elephant research: contributions to conservation of captive and free‐ranging species

“…60% of DM), and gut passage rate ( c . 21–46 hours for African elephants compared to 55 hours for Asian elephants, depending on substrate consumed) support the use of the horse as a physiologic model in feeding programmes (see Clauss, Loehlein et al ., for summary; Romain et al ., ; Das et al ., ), although elephant digestion coefficients are generally lower than horses because of their faster gastrointestinal passage rates.…”

“…Certainly zoo-based research has contributed to our knowledge of elephant digestive physiology through controlled studies. Basic investigations of intake [1-2% of body weight on a dry matter basis (DMB)], digestion (average 40-50%, range 20% to c. 60% of DM), and gut passage rate (c. 21-46 hours for African elephants compared to 55 hours for Asian elephants, depending on substrate consumed) support the use of the horse as a physiologic model in feeding programmes (see Clauss, Loehlein et al, 2003 for summary;Romain et al, 2014;Das et al, 2015), although elephant digestion coefficients are generally lower than horses because of their faster gastrointestinal passage rates.…”