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71.
Corn endosperm separated by dry fractionation could exhibit poor fermentation performance due to loss of germ components beneficial for yeast growth. Inorganic nitrogen and other nutritional supplementations are used to overcome slow fermentation rates. We investigated the use of a protease in generating free amino nitrogen (FAN) from germ as an alternative to exogenous nitrogen sources. Up to 300% more FAN can be generated from germ in 6 hr of incubation with protease than without protease. Protease incubation also resulted in higher dry solids (ds) and total glucose contents in the germ hydrolyzates. During fermentation without urea addition, ethanol yields were dependent on mash FAN concentrations. Ethanol yields increased to a maximum when FAN level was 80–90 mg of FAN/100 g ds. At half the optimal FAN level (≈40 mg of FAN/100 g ds), nitrogen limitation occurred, as indicated by high residual glucose concentrations. However, germ FAN did not increase the ethanol yields compared to urea supplementation, likely because germ FAN resulted in lower substrate consumption compared to urea supplementation. Lower substrate consumption correlated to the increase in residual maltose with increase in initial FAN. Ethanol productivity in 0–24 hr of fermentation was higher with germ FAN than with urea, thus decreasing overall fermentation time.  相似文献   
72.
This study investigated the efficacy of the essential oil (EO) of Aloysia triphylla as an anesthetic for albino and gray strains of silver catfish, Rhamdia quelen. Juveniles were exposed to concentrations between 20 and 800 μL L?1 EO of A. triphylla to evaluate time of induction and recovery from anesthesia. In another experiment, both strains were divided into four groups such as 0 (control), 30, 40, or 50 μL L?1 EO and transported for 5 h. The longest time for anesthetic induction and recovery was observed in the albinos. Both strains reached anesthesia in the 100–800 μL L?1 (11.1–1.24 min) range, without mortality, being 200 μL L?1 the best response considering time to anesthesia (5.35 min). Albinos transported with all EO concentrations showed higher values of carbon dioxide in the water of transport, but lower levels were observed in grays transported with 40 and 50 μL L?1 EO when compared to control fish. The same concentrations did not prevent significant whole-body cortisol rise at the end of transport in the albino strain. Juveniles of both strains transported with EO presented lower ion loss to the water compared to control fish. The EO of A. triphylla is an effective anesthetic for albino and gray silver catfish. This EO increases whole-body cortisol levels in the albino strain, but as it reduces net ion loss as in the gray strain, it can be also recommended for transport.  相似文献   
73.
Fitness of sugary1 (su1) is affected by some critical traits that depend on the genotypes and environments, while their effects have not been quantified with convincing statistical methods. The objective of this work was to identify and quantify the critical factors of su1 fitness with different genotypes and environments. We used two pairs of field corn inbreds that differentially affected su1 viability to develop F1, F2, BC1 and BC2. After selfing, Su1 and su1 kernels were evaluated under controlled environmental conditions and in field trials. Multiple regressions showed that dry weight of juvenile plant was affected by early vigour (plant size, colour and health) and emergence in cold conditions; ear weight by plant appearance, number of plants and chlorophyll content; number of ears by plant appearance, number of plants, chlorophyll content and female flowering; and kernel weight by ear weight, number of plants, row number and ear length. The main critical factors for su1 fitness were early vigour and emergence under cold conditions at initial stages, while several adult traits were related with final fitness.  相似文献   
74.
The performance, intake, feed efficiency, and carcass traits of beef cattle from different gender profile were assessed. Fifteen animals (five steers, five spayed heifers, and five intact heifers) with ±250 kg of initial body weight were randomly assigned in individual pens and fed the same diet for 106 days. At the end of the trial, all the animals were slaughtered and the pH, temperature, and weight of the carcass were recorded. The right side of each carcass was then separated into chuck, shoulder, flank sirloin, and round for evaluation of commercial cuts yield. The left carcass sides were ribbed between the 12th and 13th ribs where the rib eye area and fat thickness measurements were taken. The 9th–11th rib section was removed from the left half carcass and then dissected into muscle, fat, and bones in order to estimate carcass composition. Gender had no effect (P > 0.05) on performance, intake, digestibility of dry matter and all the nutrients evaluated, feed efficiency, and carcass characteristics. It can be concluded that steers and heifers (spayed or not) have the same potential to produce beef. From a productive and welfare standpoint, there is no reason to spay heifers.  相似文献   
75.
Ectinogonia buquetti (Spin.) (Coleoptera, Buprestidae) was identified as the agent causing damage on a Eucalyptus camaldulensis (Dehnh.) bioenergy plantation. Damage affected the principal apex and upper lateral branches and loss of lateral branches on E. camaldulensis due to complete ring-barking. E. buquetti is a coleopteron native to Chile, it preferably feeds on the wood of native species. A total of 205 individuals, all adults were found; 45% of the plants presented some type of damage.  相似文献   
76.
This study deals with the effects of intermittent irrigation on actual evapotranspiration (ET) and leaf area index (LAI) of “Superior” grapevines grown in a semiarid environment in northeastern Brazil. The field experiments were carried out during two consecutive fruiting cycles (dry season and rainy season) of grapevines (Vitis vinifera, L) irrigated by drip at a rate of 2.3 L h−1. Four irrigation time intervals were used as follow: one turn irrigation-time (I-1), two turn irrigation-time (I-2), three turn irrigation-time (I-3), and four turn irrigation-time (I-4). The growing cycles received different amounts of water by irrigation, which for dry and rainy seasons were 470.5 and 243.5 mm, respectively. The ET increased from 5.7 to 7.5 mm day−1 when the irrigation time interval changed from I-1 to I-4 and resulted in a higher value of LAI. The values of ET during the rainy-season growing cycle were much lower throughout the phenological stages, reaching a maximum of 6.4 mm day−1 for I-4 in the maturation stage. For both growing cycles, an increase in the cumulated vineyard evapotranspiration was observed when changing the irrigation time interval from I-1 to I-4, except I-2, which was slightly greater than I-3. Soil water drainage had a very gradual exponential decrease from I-1 to I-4 in both fruiting cycles. The grapevine coefficient under intermittent irrigation can be described as function of days after pruning by polynomial models.  相似文献   
77.
The goal of this study was to evaluate the effect of high Tween 80 concentrations on hydrocarbon contaminants and hydrocarbonoclastic microorganisms present in contaminated mining soil during a bioremediation process. The independent variables included Tween 80 concentration and process time. The elected response variables included concentration of total petroleum hydrocarbons (TPH), the chemical composition of contaminants, viable microbial count, and CO2 production. These were measured at various time points during the bioremediation process, which was conducted at room temperature. Higher removal of pollutants occurred at low Tween 80 concentrations. An analysis of the normalized variables shows that the rate of TPH degradation depended on microbial growth rate, which depended on Tween 80 concentration. The addition of Tween 80 changed the concentration and type of the residual hydrocarbon contaminants present, as well as the count and genus of the hydrocarbonoclastic microorganisms that grew during the bioremediation process. Higher concentrations of Tween 80 increased the levels of the chemical compounds present in the bioremediated soil while reducing the viable count and microbial diversity during the bioremediation process. Conversely, low Tween 80 concentrations produced only monoethylhexyl phthalate, which is not a petroleum hydrocarbon derivative. Overall, these results prove that the removal of TPH is dependent on the count and genus of active indigenous hydrocarbonoclastic microorganisms in soil, and these conditions may be controlled by modulating the concentration of Tween 80 that is applied.  相似文献   
78.
In aquaculture, nutrition and supplemented diets have been shown to affect broodstock reproductive performance. In this study, we investigated the effects of dietary supplementation with Cymbopogon flexuosus essential oil (CFEO) microcapsules on reproductive-related parameters in silver catfish (Rhamdia quelen) male broodfish. Adult male broodstocks were separated into three groups according to the concentrations of supplemented CFEO (0.0?=?control; 1.0 or 3.0 mL per kg of diet). After 20 days under experimental conditions, the animals were euthanized and the gonads were harvested for gonadosomatic index, sperm analysis, oxidative stress, and histopathology; testosterone levels were measured in the plasma; gene expression of prl, smtl, pomca, and pomcb was assessed in the pituitary gland by real-time PCR. The results showed no alterations on reproductive parameters in R. quelen males treated with Cymbopogon flexuosus essential oil compared to the control-diet animals. In conclusion, CFEO microcapsules supplied for 20 days in the concentrations of 1.00 or 3.00 mL per kilogram of diet did not affect the reproduction criteria evaluated in this study in male silver catfish.  相似文献   
79.
Dietary supplements are commonly used by animals and humans and play key roles in diverse systems, such as the immune and reproductive systems, and in metabolism. Essential oils (EOs), which are natural substances, have potential for use in food supplementation; however, their effects on organisms remain to be elucidated. Here, we examine the effects of dietary Aloysia triphylla EO supplementation on zebrafish behavior, metabolism, stress response, and growth performance. We show that fish fed diets containing A. triphylla EO presented an anxiolytic response, with reduced exploratory activity and oxygen consumption; no changes were observed in neuroendocrine stress axis functioning and growth was not impaired. Taken together, these results suggest that the A. triphylla EO supplementation is a strong candidate for use in feed, since it ensures fish welfare (anxiolytic behavior) with decreased oxygen consumption. This makes it suitable for use in high-density production systems without causing damage to the neuroendocrine stress axis and without growth performance being impaired.  相似文献   
80.
The habanero pepper is widely used in a variety of commercial food products. The increase in the cultivation area of the habanero pepper has increased the use of agricultural inputs, mainly inorganic fertilizers, which have high economic costs and cause negative effects to the soil and water. In recent years, the use of beneficial soil microorganisms has been studied as an alternative to inorganic fertilizers. In the present study, the effect of three strains of Pseudomonas putida on the growth and productivity of King Pakal hybrid habanero pepper with limited inorganic fertilizer in a greenhouse. It was found that a reduction of inorganic fertilizer application of 25% with P. putida rhizobacteria strains increased or maintained growth and productivity of King Pakal hybrid habanero pepper. Before these rhizobacteria can be used in the field, results will first need to be confirmed under more natural conditions.  相似文献   
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