32 research outputs found
Effects of a Chelated Copper as Growth Promoter on Performance and Carcass Traits in Pigs
Three studies were conducted to investigate whether a chelated Cu can replace CuSO4 as a growth promoter in pigs. In Exp. 1, a total of 240 piglets (Large White×Landrace, 7.36±0.10 kg) were randomly allocated to 1 of 3 treatments with 8 replicates and 10 piglets per pen. Treatments included a NRC control (CuSO4, 6 mg/kg), two Cu supplementations from either CuSO4 or Cu(HMTBa)2 at 170 mg/kg. Pigs fed Cu(HMTBa)2 were 6.0% heavier than pigs fed either the NRC control or 170 mg/kg CuSO4 (p = 0.03) at the end of the experiment. During the 42 days of experimental period, pigs fed Cu(HMTBa)2 gained 9.0% more (p = 0.01), tended to eat more feed (p = 0.09), and had better feed efficiency (p = 0.06) than those fed CuSO4. Compared with the 6 mg/kg CuSO4 NRC control, liver Cu was increased 2.7 times with 170 mg/kg CuSO4 supplementation, and was further increased with Cu(HMTBa)2 (4.5 times, p<0.05). In Exp. 2, a total of 616 crossbred piglets (PIC, 5.01±0.25 kg) were randomly allocated to 1 of 4 treatments with 7 replicates and 22 piglets per pen. Treatments included a NRC control (from CuSO4), and three pharmaceutical levels of Cu (150 mg/kg) supplemented either from CuSO4, tri-basic copper chloride (Cu2[OH]3Cl), or Cu(HMTBa)2. Pigs fed CuSO4 or Cu(HMTBa)2 had better feed efficiency (p = 0.01) and tended to gain more (p = 0.08) compared with those fed the NRC control. Pigs fed Cu2(OH)3Cl were intermediate. Pigs fed Cu(HMTBa)2 had the highest liver Cu, which was significantly higher than those fed (Cu2[OH]3Cl) or the negative control (p = 0.01). In Exp. 3, a total of 1,048 pigs (PIC, 32.36±0.29 kg) were allotted to 6 treatments with 8 replicates per treatment and 20 to 22 pigs per pen. The treatments included a NRC control with 4 mg/kg Cu from CuSO4, a positive control with 160 mg/kg Cu from CuSO4, and incremental levels of Cu(HMTBa)2 at 20, 40, 80, and 160 mg/kg. During the overall experimental period of 100 days, no benefit from 160 mg/kg CuSO4 was observed. Pigs fed Cu(HMTBa)2 had increased ADG (linear and quadratic, p≤0.05) and feed efficiency (linear and quadratic, p≤0.05) up to 80 mg/kg and no further improvement was observed at 160 mg/kg for the whole experimental period. Pigs fed 80 mg/kg Cu(HMTBa)2 weighed 1.8 kg more (p = 0.07) and were 2.3 kg heavier in carcass (p<0.01) compared with pigs fed 160 mg/kg CuSO4. In addition, loin depth was increased with increased Cu(HMTBa)2 supplementation with pigs fed 80 mg/kg Cu(HMTBa)2 had the greatest loin depth (p<0.05). In summary, Cu(HMTBa)2 can be used to replace high CuSO4 as a growth promoter in nursery and grower-finisher pigs
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Review of battery electric vehicle propulsion systems incorporating flywheel energy storage
The development of battery electric vehicles (BEV) must continue since this can lead us towards a zero emission transport system. There has been an advent of the production BEVs in recent years; however their low range and high cost still remain the two important drawbacks. The battery is the element which strongly affects the cost and range of the BEV. The batteries offer either high specific power or high specific energy but not both. To provide the BEVs with the characteristic to compete with conventional vehicles it is beneficial to hybridize the energy storage combining a high energy battery with a high power source. This shields the battery from peak currents and improves its capacity and life. There are various devices which could qualify as a secondary storage system for the BEV such as high power battery, supercapacitor and high speed flywheel (FW). This paper aims to review a specific type of hybridisation of energy storage which combines batteries and high speed flywheels. The flywheel has been used as a secondary energy system in BEVs from the early 1970s when the oil crises triggered an interest in BEVs. Since the last decade the interest in flywheels has strengthened and their application in the kinetic energy recovery system (KERS) in Formula 1 has further bolstered the case for flywheels. With a number of automotive manufacturers getting involved in developing flywheels for road applications, the authors believe commercial flywheel based powertrains are likely to be seen in the near future. It is hence timely to produce a review of research and development in the area of flywheel assisted BEVs
Efeito da adição de butirato de sódio, propionato de cálcio ou monensina sódica no concentrado inicial sobre parâmetros ruminais e de desenvolvimento do rúmen de bezerros leiteiros
Effect of Postweaning Age on Rate of In Situ Protein Disappearance in Calves Weaned at 5 Weeks of Age
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Effects of Rumen-Undegradable Protein Sources and Supplemental 2-Hydroxy-4-(Methylthio)-Butanoic Acid and Lysine·HCl on Lactation Performance in Dairy Cows
One hundred primiparous and multiparous Holstein cows were used in an experiment to evaluate the effect of supplementing diets with either a plant- or an animal-based source of rumen-undegradable protein (RUP), with or without AA supplementation, during the transition period and early lactation on milk production response. The experimental design was a randomized block design with approximately one-third of the cows being primiparous. Cows were assigned to 1 of 4 prepartum diets introduced 3 wk before the expected calving date and switched to the corresponding postpartum diet at calving. Diets 1 (AMI) and 2 (AMI+) included a vegetable RUP source (heat- and lignosulfonate-treated canola meal), with diet 2 containing supplemental Lys·HCl and Met hydroxy analog sources [d,l-2 hydroxy-4-(methylthio)-butanoic acid; Alimet feed supplement]. Diets 3 (PRO) and 4 (PRO+) consisted of a blend of animal RUP sources (blood meal, fish meal, feather meal, and porcine meat and bone meal), with diet 4 containing supplemental Lys·HCl and Met hydroxy analog sources [d,l-2 hydroxy-4-(methylthio)-butanoic acid; Alimet]. During the first 4 wk of lactation, dry matter intake was less when synthetic Lys·HCl and Alimet were supplemented, but this effect was no longer evident in wk 5 to 9 of the experiment. Interestingly, despite the initial decrease in dry matter intake in the cows fed AA-supplemented diets, there was no effect of treatment on milk production or the ratio of fat-corrected milk to dry matter intake throughout the 17 wk of the study. Undegradable protein source (vegetable vs. animal) did not affect dry matter intake, milk production, or 3.5% fat-corrected milk production for the first 17 wk of lactation. The results of this study indicate that heat- and lignosulfonate-treated canola meal can be used as a source of undegradable protein in place of high-quality rumen-undegradable animal protein sources without negative effects on milk production when diets are equivalent in rumen degradable protein, RUP, and metabolizable Met and Lys. Despite other reports citing clear benefits to feeding supplemental synthetic Lys or Met in diets fed to high-producing lactating dairy cows, we were unable to provide additional evidence to support these findings. Additionally, there was a trend for whole-blood Lys concentrations to be greater for diets supplemented with Lys·HCl