Effect Of Different Energy Sources Research Articles

Biochemical markers of neuro-myocardial damage after pulmonary vein isolation: the effect of different energy sources

Abstract Background Pulmonary vein isolation (PVI) by thermal energy, both radiofrequency (RF) and cryoenergy(Cryo), is associated with a significant release of myocardial and collateral neural injury markers. Damage to periatrial ganglionated plexi also results in a substantial change in cardiac autonomic regulations. On the contrary, pulsed electric field (PEF) energy tends to spare cardiac neural tissue. Purpose To quantify the impact of different ablation energy sources that are used for PVI on neuro-myocardial damage by the assessment of specific biomarkers. Methods A study enrolled 85 patients with paroxysmal atrial fibrillation who underwent PVI (age: 61 ± 12 years, 74% males). In 23 patients, RF energy was delivered by the irrigated-tip catheter, while 30 patients were ablated using a second-generation cryoballoon catheter. In 32 patients, PVI was performed using a multipolar pentaspline catheter and PEF energy. Peripheral venous blood samples for assessing the plasmatic levels of S100 calcium-binding protein B (S100B), neuron-specific enolase (NSE), high-sensitivity troponin I and T (hsTnI and hsTnT) were obtained before, immediately after the PVI, and the next day (usually 18-24 hours after the procedure). Study groups were compared regarding absolute biomarker levels and hsTnT/S100B ratio (a surrogate of cardioselectivity). Results Following successful PVI, a significant increase in plasma levels of all biomarkers was observed: DhsTnT = 1040±434 ng/L, 1731±830 ng/L and 1010±397 ng/L; DhsTnI = 1504±918 ng/L, 16464±11911 ng/L and 10789±7589 ng/L; DS100B: 0.04±0.02 mg/L, 0.03±0.04 mg/L and 0.14±0.08 mg/L; DNSE: 34±72 ng/mL, 27±53 ng/mL and 45±52 ng/mL (all with P <0.001) for RF, PEF and Cryo groups, respectively. A direct comparison of maximal biomarker levels between study groups is depicted in the Figure. The hsTnT/S100B ratio was 23±14, 12±6, and 6±3 in PEF, RF, and Cryo groups, respectively (ANOVA P <0.01), indicating that PEF was 1.9-times and 3.8-times more cardioselective than RF and Cryo, respectively. Following the PVI, the heart rate accelerated by 2±8, 13±14, and 9±11 bpm in the PEF, RF, and Cryo groups, respectively. No correlation was observed between S100B release and HR acceleration (R = 0.07, P = 0.55). Conclusion Compared to thermal energy sources, PEF energy induces more specific damage to cardiomyocytes than cardiac nerves. There was no correlation between S100B release and HR acceleration.

The effect of different energy sources on the performance and blood metabolites of sheep

Energy has an important role in metabolic processes. Dietary energy sources can be in the form of carbohydrates or fat. This study aimed to elaborate the performance and blood metabolites of ewes fed cassava, palm oil or canola oil. Sixteen ewes were divided into four groups of four treatments, namely T1 = 100% grass; T2 = 40% grass + 30% concentrate + 30% cassava; T3 = 40% grass + 50.3% concentrate + 9.7% palm oil; T4 = 40% grass + 50.3% concentrate + 9.7% canola oil. Randomized block design was used and data were analyzed using analysis of variance and any differences were furthered tested by Duncan multiple range test. The results showed that feeding with different energy sources significantly (P<0.05) had a significant effect on feed consumption and digestibility, weight gain, and feed utilization efficiency. The feed consumption of 100% grass ration (T1) was significantly higher than the other treatments. Diet with 30% cassava (T2) had significantly different feed digestibility and performance from the 100% grass and oil treatment. The blood cholesterol content of sheep fed with oil (T3 and T4) was higher than that given 100% grass (T1) and 30% cassava (T2). However, there were no differences among the treatment on blood glucose and protein concentration. It is concluded that the provision of 30% cassava resulted in better sheep performance and lower blood cholesterol levels compared to feeding with an energy source in the form of oil.

Lactate as the sole energy substrate induces spontaneous acrosome reaction in viable stallion spermatozoa.

Equine spermatozoa appear to differ from spermatozoa of other species in using oxidative phosphorylation preferentially over glycolysis. However, there is little information regarding effects of different energy sources on measured parameters in equine spermatozoa. To determine the effect of three individual energy substrates, glucose, pyruvate, and lactate, on motion characteristics, membrane integrity, and acrosomal status of stallion spermatozoa. Freshly ejaculated stallion spermatozoa were incubated with combinations of glucose (5mm), pyruvate (10mm), and lactate (10mm) for 0.5 to 4h. Response to calcium ionophore A23187 (5μm) was used to evaluate capacitation status. Motility was evaluated using computer-assisted sperm analysis, and plasma membrane and acrosomal integrity were evaluated by flow cytometry. Incubation with lactate alone for 2h increased acrosomal sensitivity to A23187. Notably, incubation with lactate alone for 4h induced a significant spontaneous increase in acrosome-reacted, membrane-intact (viable) spermatozoa, to approximately 50% of the live population, whereas no increase was seen with incubation in glucose or pyruvate alone. This acrosomal effect was observed in spermatozoa incubated at physiological pH as well as under alkaline conditions (medium pH approximately 8.5). Sperm motility declined concomitantly with the increase in acrosome-reacted spermatozoa. Sperm motility was significantly higher in pyruvate-only medium than in glucose or lactate. The addition of pyruvate to lactate-containing medium increased sperm motility but reduced the proportion of live acrosome-reacted spermatozoa in a dose-dependent fashion. This is the first study to demonstrate that incubation with a specific energy substrate, lactate, is associated with spontaneous acrosome reaction in spermatozoa. The proportion of live, acrosome-reacted spermatozoa obtained is among the highest reported for equine spermatozoa. These findings highlight the delicate control of key sperm functions, and may serve as a basis to increase our understanding of stallion sperm physiology.

Identification of environmental hotspots in fishmeal and fish oil production towards the optimization of energy-related processes

This study assessed the environmental impacts of a pelagic fishmeal and fish oil production plant in Iceland with the life cycle assessment methodology. The study focused on assessing the effects of different energy sources for utility production due to the high energy intensity of fishmeal and fish oil production, as quality improved with lower cooking temperature. The environmental hotspots of three different processing scenarios were assessed, where the factory was run on hydropower (Scenario 0), heavy fuel (Scenario 1) and a composition of both (Scenario 2), from cradle-to-factory gate. Midpoint results showed that the raw material acquisition contributed the most to the environmental impact when the fishmeal factory was operating on hydropower. However, drying had the highest impact when heavy fuel oil was used for utility production. This study also demonstrated that lowering the cooking temperature from 90 to 85 °C, led to improved quality and simultaneously reduced environmental impacts during processing. This indicated that a small energy adjustment in the production can have an environmental gain, demonstrating the necessity to optimize each processing step in the fishmeal and fish oil production process both for increased product quality and minimizing environmental impacts.

The effect of using different energy sources and levels on carcass weight, breast muscle mass, mTORC1 and AKt gene expression in Cobb 500 broiler chicks

The present study was aimed to evaluate the effect of different energy sources and levels on carcass weight, breast muscle mass mTORC1 and AKt gene expression in Cobb 500 broiler chicks. A total of 600 1-day-old Cobb 500 broiler chicks with an average weight of 39 ± 0.50 g were randomly divided into five treatments. Each treatment was further divided into four replicates. Chicks were fed by basal diet based on corn and energy level by Cobb 500 instruction manual as control group, basal diet with 3% lesser energy than control (T1), basal diet with 6% lesser energy than control (T2), basal diet based on corn and fat level according to Cobb 500 instruction manual (T3), basal diet based on corn and fat with 3% upper energy (T4) for 42 days. To assess carcass characteristics two chicks of each replication were slaughtered and weighted after picking the carcasses. After DNA extraction, the UV spectrophotometric method was performed for determines the quality and quantity and Real-time PCR was performed on the corresponding cDNA synthesized from each sample. Data from this study showed that there were significant differences about carcass and breast muscle weight between treatments (P &lt;0.05). As result obtained from this study the highest mTORC1 and AKt gene expression were for T4 and T3, T2, T1 had higher gene expression compared to control respectively. In conclusion higher levels of energy are needed for Cobb 500, for both mTORC1 and AKt gene expression as well as the more carcass and breast muscle influences.

Study into the effect of different energy sources on the structure and mechanical properties of EP693 nickel alloy weld joint

The paper provides the results of a study on the influence of welding types (laser, electron beam, and TIG welding) on the properties of a permanent connection made of an EP693 alloy of the Ni–Cr–W–Co–Mo system used in the production of gas turbine engine components and parts. EP367 filler wire of the Ni–Mo–Cr–Mn system was used to obtain a weld during laser and TIG welding. A comparative analysis of heating areas and power densities was performed for the welding types studied. It was established that TIG welding features by greater values of the heating area and power density in comparison with laser and electron beam welding. It was found that the type of welding affects the features of weld formation. For example, a weld is formed with the transition to knife fusion penetration in the weld root for electron beam welding, and in the form of an «hourglass» for laser welding. The analysis of the heat affected zone microstructure showed that the smallest grain size is formed during laser welding. The distribution of elements in the weld joint was analyzed. It was found that when welding with the use of filler wire, the Mo content increases and the W, Co, Al, and Ti content decreases in the weld and heat affected zone relative to the base metal. This determines the peculiarities of failure for samples obtained using the welding types studied. Samples obtained by TIG and laser welding broke along the heat affected zone on the weld reinforcement side. Samples obtained by electron beam welding broke along the weld. Mechanical tests of samples at room and elevated temperatures showed that samples obtained by laser and electron beam welding have the highest tensile strength.

Effects of different energy source diets, as corn substitutes, on carcass characteristics and meat quality of feedlot lambs

This study evaluated the effects of different energy sources, as corn substitutes, on the carcass characteristics and meat quality of lambs. Twenty-four intact ram lambs were identified, weighed, and assigned to one of four dietary treatments: corn, citrus pulp, rice bran, and soybean hulls. The ram lambs were confined in feedlots, and when they reached 30 kg of live weight, they were slaughtered. A completelyrandomized design with different replicates was used for the analysis, along with the Tukey-5% test. For hot and cold carcass weight, rice bran produced lower values than the other dietary treatments. For the red color content of the meat, citrus pulp presented superior values when compared to corn, whereas meat and fat color, loin eye area, and objective tenderness did not differ between treatments. Different energetic sources used to replace corn in ram lambs finishing diets did not affect the proximate composition and quality of the meat. Highlights: • Addition of rice bran to the lambs' diet resulted in lower hot and cold carcass weight.• Animals fed soybean hulls presented the highest carcass compactness index values.• Rice bran extended the feedlot period of lambs in 59.33 days, been longer than the others energies sources.• Corn, rice bran, citrus pulp and soybean hulls did not change the quality of meat but the inclusion of rice bran should be carefully evaluated.

CO &lt;sub&gt;2&lt;/sub&gt; Well-to-Wheel Abatement with Plug-In Hybrid Electric Vehicles Running under Low Temperature Combustion Mode with Green Fuels

&lt;div class="section abstract"&gt;&lt;div class="htmlview paragraph"&gt;Plug-in Hybrid Electric Vehicles (PHEVs) can be considered as the most promising technology to achieve the European CO&lt;sub&gt;2&lt;/sub&gt; targets together with a moderate infrastructure modification. However, the real benefits, in terms of CO&lt;sub&gt;2&lt;/sub&gt; emissions, depend on a great extent on the energy source (fuel and electricity mix), user responsibility, and vehicle design. Moreover, the electrification of the powertrain does not reduce other emissions as NOx and particulate matter (mainly soot). In the last years, low temperature combustion (LTC) modes as the reactivity controlled compression ignition (RCCI) have shown to achieve ultra-low NOx and soot emissions simultaneously due to the use of two fuels with different reactivity together with high exhaust gas recirculation (EGR) rates. Therefore, the aim of this work is to assess, through numerical simulations fed with experimental results, the effects of different energy sources on the performance and emissions of a series RCCI PHEV. The dual-fuel engine was fueled with diesel as high reactivity fuel and bioethanol as low reactivity fuel. The powertrains are optimized to meet the European homologation legislation (WLTP) for PHEVs. The tailpipe emissions and fuel consumption of the series RCCI PHEV is analyzed and compared to the OEM no-hybrid passenger vehicle running under conventional diesel combustion and RCCI. A life-cycle analysis (LCA) is performed to evaluate the potential of the different energy sources to reduce the overall CO&lt;sub&gt;2&lt;/sub&gt; emissions. Different electricity sources are investigated as well as different liquid fuels: e-diesel and bio-ethanol. The series RCCI PHEV technology achieved the tank-to-wheel 50 g/km CO&lt;sub&gt;2&lt;/sub&gt; emissions target with medium battery size (13 kWh). In addition, thanks to the RCCI technology, the vehicle is able to meet the Euro 6 NOx and soot limits. The LCA shows that, depending on the fuel source, the total CO&lt;sub&gt;2&lt;/sub&gt; reduction benefits variate. Also, the final use and the charging events of the series PHEV have a great impact in this sense.&lt;/div&gt;&lt;/div&gt;

389 Effects of energy source on performance and carcass characteristics in hair lambs finished in feedlot

Abstract The objective of this study was to evaluate the effects of different energy sources on performance, and carcass characteristics in hair lambs finished in feedlots. Twenty-eight hair lambs with an initial body weight (BW) 20.8 ± 3.01, were randomly assigned to one of four dietary treatments included with seven lambs per treatment. The dietary treatments included an energy source included at 18% Dry matter: S. spectabilis flour (SF), palm kernel (PK), corn bran (CB) and rice bran (RB) in a diet based in corn silage, ground corn, soybean meal formulated to 13.0% PC and 2.6 Mcal/Kg of DM. The feeding trial was performed for 13 weeks. Water was allowed ad libitum. Animals were slaughtered after the feeding trial, and the carcasses were kept at 4°C for 24 h under Colombian standard guidelines. Data were analyzed by using the ANOVA procedure, SAS version 9.1 to perform a randomized complete experiment with four diets. For each studied variable, the mean and standard error of the mean (SEM) were calculated and differences between means were evaluated Using Tukey′s Test (P ≤ 0.05). Final body weight, hot carcass weight, cold carcass weight, hot dressing carcass (%), and cold dressing weight (%) were not different between the four treatments (P &amp;gt; 0.05). Dry matter intake was superior to the S. spectabilis flour (P &amp;lt; 0,001). Feed efficiency was higher in the CB and RB treatments (P &amp;lt; 0,05). These results indicate that the inclusion of S. spectabilis and palm kernel could improve the dry matter intake and corn bran and rice bran the feed efficiency without effects on carcass characteristics

116 Effect of different energy sources on motility and calcium ionophore-induced acrosome reaction in equine sperm

Equine sperm appears to differ from sperm of other species, preferring oxidative phosphorylation over glycolysis for energy production. However, there is little information about the effects of different energy sources on capacitation-related events in equine sperm. We evaluated stallion sperm incubated in the presence of different energy sources at a pH (~8.3) known to support some aspects of capacitation. Fresh stallion semen (n=9 ejaculates) was washed, then diluted to 30×106 spermmL−1 with modified Whitten's medium containing 25mM bicarbonate, 7mgmL−1 bovine serum albumin (BSA), and only one energy source (5mM glucose, 10mM lactate, or 10mM pyruvate). The diluted sperm were incubated in air for 0.5, 2, or 4h, then exposed to 5 µM calcium ionophore A23187 (CaI) or vehicle (V) for 10min. Sperm were washed and incubated in the assigned medium for 30min, then evaluated by computer-assisted sperm motility analysis and by live/dead staining (Fixable Live/Dead Red, Molecular Probes) followed by fixation (2% v/v paraformaldehyde) and staining for acrosome reaction, using Pisum sativum agglutinin (FITC-PSA, Sigma Aldrich). Stained sperm were evaluated via flow cytometry to detect live acrosome-reacted sperm. Data were analysed using ANOVA with Tukey post hoc comparison (SAS 9.4, SAS Institute). Medium pH at 4h was 8.37 to 8.48. There were no significant differences between CaI and V treatments for any experimental endpoint (P&amp;gt;0.05). At 4h, pyruvate values for total motile sperm (46±5%) and curvilinear velocity (113±8µm s−1) were significantly higher than those for lactate (32±5% and 86±5µm s−1) or glucose (27±4% and 90±5µm s−1). The percentage of live sperm that were acrosome-reacted (%L-AR) did not increase significantly until 4 h; at this time,%L-AR was higher for lactate (46±3%) than for pyruvate (21±3%) or glucose (18±3%; P&amp;lt;0.05). To the best of our knowledge, this is the first critical evaluation of the effect of different energy sources on motility and acrosome reactivity of equine sperm. The higher motility in pyruvate supports the concept that stallion sperm utilises oxidative phosphorylation more effectively than glycolysis. The apparent lack of effect of CaI on%L-AR may be related to the 1- to 2-h delay typically seen after its use in equine sperm; the present data show that incubation even for 4h in potentially capacitating conditions does not prepare equine sperm to respond quickly to CaI. Surprisingly, a high rate of spontaneous acrosome reaction was achieved in the lactate treatment. The notably higher%L-AR with lactate than with pyruvate suggests that this effect is not due to utilisation of substrate for oxidative phosphorylation but may be associated with conversion of lactate to pyruvate via lactate dehydrogenase, or possibly with effects of lactate through other pathways. Although pyruvate was associated with greater motility, this could be related to higher oxidative stress, which could have influenced the%L-AR. Further work is needed to determine whether the acrosomal changes observed are related to functional capacitation.

131 Milk yield of ewes fed with diets of different energy levels

Abstract An adequate sheep milk production ensures survival and optimum lamb’s growth and development through the weaning. To evaluate the effects of different energy sources in the diet of ewes on their milk yield, an experiment was carried out at the Faculty of Animal Science and Food Engineering of USP, Brazil, using 56 pregnant ewes, Dorper and Santa Ines breeds, average live weight of 70 kg, randomly distributed in four treatments: control group (fed according to the 2007 NRC recommendation); and groups with 10% more energy with different sources (starch, ST; protected fat, PF; and chromium, Cr). Dry matter intake was approximately 3% of the live weight of the ewes, to all treatments, but the control group with intake of 2.1 Mcal EM/d and the other with 2.3 Mcal EM/d. Ewes were fed the experimental diets at the beginning (50 d) and end of the gestation (50 d). In the middle of the gestation (50 d) the sheep were fed according to the recommendation of the NRC (2007). At 20, 30, 40, 50, and 60 days post-lambing, the milk yield was assessed using an indirect method of double weighing the lambs (one weight before suckling, another weight after suckling). The ewe milk yield was analyzed using contrasts and statistical significance at 5% of probability. There was no statistical difference (P &gt; 0.05) among the diets evaluated on milk yield of the ewe (0.42, 0.45, 0.38, 0.3, and 0.14 kg/d for 20, 30, 40, 50, and 60 days of lactation). We concluded that milk yield of ewes receiving different levels and source of dietary energy did not differ. Additionally, the use of Cr or protected fat did not influence milk yield when added at 10% of the required energy for lactation. Acknowledgment to FAPESP (process 2017/20555–8).

Rebound effect of energy efficiency in China's construction industry: a general equilibrium analysis.

China has set ambitious targets to reduce its carbon intensity by 2020. Improved energy efficiency is an important strategy to achieve this goal. However, the rebound effect may act as a major obstacle to fully realizing the potential for energy savings. As one of three major energy consumption sectors in China, the construction industry is vital to reducing carbon emissions. This paper established a static computable general equilibrium (CGE) model to study the rebound effect of different energy sources used in the construction industry. The main energy sources used in the construction industry are coal, oil, natural gas, and electricity, and the conclusions show that the largest rebound effect was found for improvements in natural gas efficiency, with an average of 99.20%, while the lowest was for improvements in electricity efficiency, with an average of 83.47%. Moreover, the rebound effect of the primary energy sources (coal, oil, natural gas) was greater than the rebound effect of the secondary energy source (electricity). Our conclusions indicate that improving the energy efficiency in the construction industry will have a positive impact on GDP and on the mitigation of carbon emissions, and the presence of the rebound effect is significant, especially with regard to electricity sources. The implications of the results are that policymakers should primarily focus on improving the efficiency of electricity. In addition, this paper suggests that the rebound effect can be reduced by removing fossil fuel subsidies and imposing a carbon tax.

Supplementation of grazing suckling beef calves receiving different energy sources

The aim of this study was to evaluate the effect of different energy sources - corn, sorghum, and wheat bran - on performance, intake, digestibility, and nitrogen utilization efficiency of beef calves subjected to creep feeding. Thirty-four calves (12 males and 22 females) with initial age and weight of four months and 108±3.9 kg, respectively, were used in a randomized-block experimental design with four treatments and two blocks (males and females). Treatments were control (MM), a mineral mixture ad libitum; corn (C); corn + sorghum (C+S); and corn + sorghum + wheat bran (C+S+WB). Supplements contained approximately 20% crude protein (CP), and were fed in the amount of 0.5% of body weight. Supplemented animals had higher performance (P &amp;lt; 0.05) when compared with those on treatment MM. Supplementation increased (P &amp;lt; 0.05) the intakes of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber corrected for ash and protein (NDFap), non-fibrous carbohydrates (NFC), digestible neutral detergent fiber (dNDF), and digestible organic matter (dOM). The digestibility of NFC was higher (P &amp;lt; 0.05) in the supplemented treatments. The C+S and C+S+WB treatments provided increased digestibility (P &amp;lt; 0.05) of OM, CP, and NDFap. The synthesis of nitrogen compounds was higher (P &amp;lt; 0.05) in animals on treatment C as compared with those on the other supplemented treatments. Animals on treatments C+S and C+S+WB had higher (P &amp;lt; 0.05) nitrogen utilization efficiency compared with those on the other treatments. Concentrate supplementation improved the animal performance. The use of other energy sources (sorghum or wheat bran) in association with corn is recommended for suckling calves.

Effects of different energy sources on cell adhesion and bioleaching of a chalcopyrite concentrate by extremophilic archaeon Acidianus copahuensis

Bioleaching is an alternative technology for recovering metals from mineral ores; thermophilic microorganisms instead of mesophiles can greatly improve metal solubilization, particularly from refractory mineral species. Acidianus copahuensis is a new species of thermophilic archaea, recently isolated in our laboratory. The effect of culture growth history on the attachment of A. copahuensis to a chalcopyrite concentrate was investigated in shake flasks at 65°C. Cells adapted to growth with chalcopyrite as energy source showed higher attachment to the mineral concentrate. A. copahuensis cells reached 100% of copper extraction in the bioleaching of chalcopyrite concentrate carried out in shake flasks cultures incubated at 65°C and pH2.0. This high bioleaching yield was achieved even at that not so low initial pH value probably because this archaeal species is able to form sufficient amounts of ferric iron but keeping low redox potential (Eh) values. This work also describes the effect of the addition of other energy sources on the bioleaching activity. A. copahuensis achieved the best copper extraction without any addition but copper extraction decreased when alternative substrates were added.

Effect of different energy sources on feed consumption, weight gain and feed conversion ratio in broilers

The 400 straight run, day old Vencobb broilers chicks were randomly divided into four treatment groups of 100 birds each viz., control, T1, T2 and T3. Each group was further divided into two replications of 50 birds each. Four iso-caloric and iso-proteinous experimental rations were formulated by replacing maize with jowar, bajra and broken rice at 25 %. The control group having diet with 100 % maize. The soyabean meal was the sole protein source for all the four rations (control, T1, T2 and T3). The observations of the parameters were taken on weekly basis and were analysed by using Completely Randomized Design (CRD) and simple arithmetic calculations. The use of different energy sources i.e. jowar, bajra and broken rice can be very well replaced with maize in broiler ration without affecting the performance of the broiler.

Incidência de doenças no pós-parto de primíparas da raça holandesa alimentadas com diferentes fontes energéticas durante o período de transição

Avaliaram-se o efeito da adição de diferentes fontes energéticas na dieta de vacas primíparas leiteiras, durante o período de transição, sobre a produção e a composição do leite, as ocorrências clínicas no pós-parto e sua relação com as concentrações plasmáticas de ácidos graxos não esterificados (AGNE). Foram utilizadas 50 vacas primíparas da raça Holandesa no período de 28 dias antes da data prevista do parto até o 21º dia pós-parto. Os animais foram designados aos grupos: controle, Megalac- E®, soja tostada (ST) ou propileno glicol (PG). Avaliações clínicas foram realizadas todos os dias. Amostras de sangue foram coletadas no pré e pós parto, antes da primeira alimentação do dia, para avaliação de AGNE. Os grupos Megalac- E® e propileno glicol apresentaram maior volume de leite corrigido para 3,5% de gordura (LCG 3,5%) em relação ao grupo soja tostada (P=0,05). Nos grupos controle, Megalac- E® e soja tostada, os valores de AGNE aumentaram até o parto, seguidos de queda após o parto. Essa queda foi menos acentuada no grupo-controle, que apresentou equação de regressão quadrática, estando associado à maior incidência de afecções no pós-parto. O grupo Megalac-E® apresentou comportamento cúbico, o soja tostada hiperbólico, e o propileno glicol quadrático.

Primeira onda folicular e ovulação de vacas primíparas da raça Holandesa alimentadas com diferentes fontes energéticas durante o período de transição

Avaliou-se o efeito da adição de diferentes fontes energéticas na dieta de vacas leiteiras, durante o período de transição, sobre a primeira onda folicular e o intervalo parto-primeira ovulação. Foram utilizadas 40 vacas primíparas da raça Holandesa, no período de 28 dias antes da data prevista do parto até o 46º dia pós-parto. As vacas foram submetidas a quatro tratamentos (grupos) durante o período de transição: grupo-controle e grupos tratados com, Megalac-E (sais de cálcio de ácidos graxos da soja), soja tostada ou propileno-glicol. Avaliações ultrassonográficas foram realizadas do 10º ao 46º dia pós-parto, com a classificação dos folículos ovarianos em quatro classes (I, II, III e IV) de tamanho e do registro do volume do tecido luteal. Amostras de sangue foram coletadas nos dias 10, 17, 24, 31, 38 e 45 após o parto para análise de progesterona. O padrão de crescimento folicular mais eficiente foi apresentado pelos animais dos grupos Megalac-E e propileno-glicol, que foram caracterizados pela redução no número de folículos de classes I e II e aumento no número de folículos de classes III e IV. Os intervalos entre o parto e a primeira ovulação dos grupos controle, Megalac-E, soja tostada e propileno-glicol foram de 29, 23, 30 e 37 dias, respectivamente (P&lt;0,05).

Fontes de energia em suplementos múltiplos de auto-regulação de consumo na recria de novilhos mestiços em pastagens de Brachiaria decumbens durante o período das águas

Objetivou-se avaliar o efeito de diferentes fontes energéticas em suplementos múltiplos de auto-regulação de consumo sobre o ganho médio diário (GMD), ganho de peso total (GPT), pH e a concentração de amônia ruminal em novilhos recriados em pastejo no período das águas. Foram avaliados suplementos contendo grão de milho moído (GMM), milho desintegrado com palha e sabugo (MDPS), sorgo moído (SM) e tratamento controle (mistura mineral - MM). Utilizaram-se 16 novilhos mestiços Holandês-Zebu, não-castrados, com 12 meses de idade e peso médio inicial de 265 kg para avaliar o desempenho. Os parâmetros ruminais foram obtidos utilizando-se quatro novilhos mestiços Holandês-Zebu fistulados no rúmen. O pH do líquido ruminal variou de 6,43 a 6,62 (média de 6,55), não sendo influenciado pelas quantidades de sal e de suplemento consumidas. As concentrações de amônia foram de 9,61; 25,71; 24,45 e 26,04 mg/dL, respectivamente para os tratamentos MM, GMM, MDPS, SM. Não se verificou diferença entre os tratamentos, contudo o suplemento MDPS proporcionou ganhos adicionais em torno de 220 g/animal/dia. Maiores concentrações de amônia ruminal foram observadas nos animais suplementados.

The effect of maize starch or soya-bean oil as energy sources in lactation on sow and piglet performance in association with sow metabolic state around peak lactation

AbstractThe effects of different energy sources in the lactation diet on sow and piglet performance were assessed in association with effects on the metabolic state of the sow around peak lactation. Either maize starch (S) or soya-bean oil (F) was added to a basal diet to provide 0·34 of total digestible energy (DE) intake, such that the experimental diets provided the same daily intakes of DE and crude protein. Twenty-four multiparous sows were allocated between two groups at farrowing, each given one of the two dietary treatments for a lactation period of 28 days. Sow weight and backfat (P2) as well as individual piglet weights were measured on a weekly basis. Litter sizes were standardized to 10 piglets. Milk samples were collected from sows on days 8, 12, 17, 21 and 25 of lactation to measure milk composition and prolactin concentrations. Blood samples were taken via an ear vein catheter from a subsample (7 S, 6 F) of sows on day 14 of lactation; two pre- and seven post-feeding samples were taken at 60-min intervals to measure plasma prolactin, insulin, glycerol, triglyceride, non-esterified fatty acid, urea, b-hydroxybutyrate and glucose concentrations. There was no effect of energy source on sow weight or P2 loss or on subsequent weaning-to-oestrus interval. Sows offered starch weaned more piglets than sows offered soya-bean oil (9·4 v. 8·4, P &lt; 0·05). Litter weight gains were higher for S than F sows in week 3 of lactation (2·2 v. 1·7 kg/day, P &lt; 0·05), irrespective of litter size. Significantly increased plasma urea and b-hydroxybutyrate concentrations and lower post-prandial increases in plasma glucose and insulin concentrations were observed in F sows around peak lactation. Neither milk nor plasma prolactin concentrations were significantly affected by dietary treatments. The metabolic indices indicated that the F diet was more limiting in dietary glucose availability, which was associated with impaired milk yield as indicated by poorer litter performance. In conclusion, this study suggests that starch is superior to fat as an energy source in sow lactation diets, particularly in the later stages of lactation.

Effects of different energy sources on metabolic state and production performance of lactating sows

Starch and fat are the two major energy sources available for sow lactation diets. Fat is more energy dense and can be used to maximise energy intakes, particularly in sows with low appetite. However, the quantity of milk produced in sows has been associated with milk lactose production and the main precursor for lactose is glucose, for which dietary starch is the major source. It is therefore important to know the consequences of using a glucose deficient energy source, such as fat, compared to starch in lactation diets. The following experiment was designed to assess energy sources in lactation diets at an isocaloric level in determining sow and piglet performance, in association with the effects of dietary glucose availability on the metabolic state of the sow around peak lactation.