Energy requirements for maintenance and growth of entire male Bali cattle in East Timor

Abstract

The metabolisable energy (ME) requirements for maintenance and growth of entire male Bali cattle (Bos javanicus) were determined by regressing liveweight change on ME intake. Cattle were fed either a diet (DM basis) of 52.5% urea-treated rice straw plus 47.5% fresh leucaena forage (Expt 1), or fresh leucaena forage alone (Expt 2). In each experiment, liveweight change and feed intake were measured over 4 weeks, after a 1-week introductory period, and feed constituent digestibilities were measured during the final week. In Expt 1, 10 bulls between 1.5 and 3 years of age and weighing 123.7 ± 11.79 kg (mean ± s.d.) were allocated to DM intakes estimated to provide 0.75, 1.0, 1.25, 1.5, 1.75, or 2.0 times the estimated ME requirement for maintenance (based on calculations made from published CSIRO equations for tropical cattle species other than B. javanicus), with either one or two bulls per treatment. In Expt 2, the bulls were given treatments estimated to provide 0.85, 1.0, 1.4, 1.8, or 2.2 times the ME requirement for maintenance, with two bulls allocated to each treatment. The measured ME requirements for maintenance were 0.42 ± 0.369 and 0.40 ± 0.153 MJ/kg LW0.75.day (coefficient ± standard error, Expts 1 and 2, respectively). The ME requirement for ‘production’ (i.e. positive liveweight change of male Bali cattle under the specific conditions of the experiment) was calculated to be 39.2 MJ/kg liveweight gain in Expt 2. The calculated efficiency of use of dietary ME for production in Expt 2, was 0.34

Metabolizable energy requirement for maintenance estimated by regression analysis of body weight gain or metabolizable energy intake in growing pigs

“…Maintenance energy requirement should be independent of the animal’s production state and nutritional levels, and therefore, it should be related to animal characteristics only [3]. Furthermore, the energy requirement for maintenance is an important part of net energy (NE) system, and accuracy of estimation of the energy requirements for maintenance will influence the absolute NE value of a feed ingredient [4–6].…”

“…Energy requirements for maintenance can be estimated us ing body weight (BW) gain as an indirect index of energy retention by the regression analysis method [4,5]. Yuliarty et al [6] reported that metabolizable energy requirements for maintenance (ME m ) of entire male Bali cattle in East Timor determined by regressing BW change against metabolizable energy intake (MEI). Compared to the method of determination the heat leaving the animal’s body, one advantage of this method is that the measurement of BW can be very precise [7].…”

Metabolisable energy requirements for maintenance and gain of liveweight of Bali cattle (Bos javanicus)

“…This value was estimated by regression of estimated ME intake against LWG of Bali cattle across a range of diets typically found in tropical regions that were variable for digestibility, and estimated ME and CP contents. This value is higher than the 0.40 MJ ME/kg LW 0.75 .day reported by Yuliaty et al (2014) to be required to maintain LW of growing Bali cattle. The estimate of ME required to maintain LW of Bali cattle in the present study is within the range of values reported for Bos indicus and Bos taurus cattle elsewhere (Solis et al 1988;Tangjitwattanachai et al 2009;Cardenas-Medina et al 2010); however, the data suggest that this class of Bali cattle may have a lower efficiency of use of ME for LWG than other cattle species.…”

“…Bali cattle in Timor Leste were estimated to require 0.40-0.42 MJ ME/kg LW 0.75 . day for maintenance of LW and 39.2 MJ ME/kg LWG (Yuliaty et al 2014). These values were derived from a limited dataset and assume that the efficiency of use of dietary ME does not vary with diet quality.…”