Optimal concentrations of lysine, methionine, and threonine in milk replacers for calves less than five weeks of age

The AA requirements of herd-replacement calves less than 5 wk old and fed milk replacers are not clearly defined and have been estimated in a limited number of studies using milk-fed calves ranging from 5 to 20 wk of age. The objective of these 4 studies was to investigate the effect of supplementing milk replacers containing 24 to 28% crude protein (CP; from milk sources) and 17% fat with Lys, Met, and Thr to estimate the optimum requirements for calves less than 5 wk of age. Holstein bull calves (initially 3 and 4 d old, 43 ± 1 kg of body weight, BW) were fed an 18% CP (as-fed) starter ad libitum and weaned at 31 to 32 d of age (28-d studies). Calves were housed in an unheated, curtain-sided nursery. In study 1, 6 milk replacer treatments were fed based on the combination of 3 CP concentrations (24, 26, and 28% CP) each with or without added Lys and Met. In studies 2 and 3, 26% CP and 2.34% Lys milk replacer treatments were fed to test the concentration of Met (0.64, 0.68, and 0.72% Met in study 2 and 0.64, 0.72, and 0.80% Met in study 3). In study 4, 26% CP, 2.34% Lys, and 0.72% Met milk replacer treatments were fed to test the concentration of Thr (1.06, 1.43, and 1.80%). There was a 17% improvement in average daily gain (ADG) in study 1 from adding Lys and Met that was maximized with 2.34% Lys. The ADG response to added Met in studies 2 (linear) and 3 (quadratic) were 13 and 7%, respectively, with a plateau at 0.72% Met. There was no ADG or efficiency response to added Thr in study 4. Formulating 17% fat, whey-based milk replacers fed at 0.68 kg/d to 26% CP, 2.34% Lys, and 0.72% Met appeared optimum based on responses of body weight gain, feed efficiency, and serum concentrations of urea nitrogen, while feeding calves more CP and essential AA did not improved ADG and efficiency. Requirements for calves less than 5 wk old, averaging 48 kg of BW, consuming 204 g of CP/d, and gaining 0.46 kg of BW/d, appeared to be met with 17 g of Lys, 0.31 Met:Lys ratio, 0.54 Met+Cys:Lys ratio, and a Thr:Lys ratio less than 0.60.     

Influence of segmental joints on tunnel lining

A simplified method for evaluating the moment carrying of a segmental tunnel liner was proposed using a result from a FEM analysis in which parameters were obtained by calibration against a true scale model test. Influence of segmental joint, number of segment and soil subgrade modulus on the bending moment carrying characteristics of a segmental tunnel was examined. Joint was represented by a series of springs called angular joint stiffness. Based on a set of model tests, practical range of angular joint stiffness was in range of 1000–3000 kN m/rad. It was found that jointed lining carried smaller value of maximum bending moment than the non-jointed one. The reduction in bending moment, represented by the parameter called moment reduction factor, can be simply expressed as a function of angular joint stiffness and number segment.     

Varietal influence of cassava on chemical composition and consumer acceptability of gari

Effects of cassava variety on chemical composition and consumer acceptability of gari were investigated. Three traditional cassava varieties Bonoua 2, Yace and Yavo as well as four improved cassava varieties Bocou 1, Bocou 2, Bocou 3 and TMS (2) 1425 were evaluated. All the varieties had appreciable high value of carbohydrates ranged from 86.6% (TMS (2) 1425) to 90.89% (Bonoua 2). TMS (2) 1425 had the lowest reducing sugar value (0.22%) while Bocou 3 had the highest reducing sugar value (0.38%). Studied gari exhibited low value of hydrogen cyanide with the lowest value found in Bocou 1 (1.53 mg per 100 g). Total fibre value varied to 2.88% (Yace) to 2.28% (Bocou 2). Gari of Bocou 1 and Bocou 3 were the most appreciated. These gari had fairly sweet taste, were fairly bright and contained few impurities. This study demonstrated that cassava variety influenced the chemical composition and consumer acceptability of gari.