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131.
Phytoparasitica - This study aimed to compare the susceptibility of tomato pinworm, Tuta absoluta, from four Brazilian regions to insect growth disruptor (IGD) insecticides by tomato leaf-dip...  相似文献   
132.
Two studies were conducted to investigate the effect of Bacillus amyloliquefaciens CECT 5940 (BA) as a probiotic on growth performance, amino acid digestibility and bacteria population in broiler chickens under a subclinical necrotic enteritis (NE) challenge and/or fed diets with different levels of crude protein (CP). Both studies consisted of a 2 × 2 factorial arrangement of treatments with 480 Ross 308 mix-sexed broiler chickens. In study 1, treatments included 1) NE challenge (+/−), and 2) BA (1.0 × 106 CFU/g of feed) supplementation (+/−). In study 2, all birds were under NE challenge, and treatments were 1) CP level (Standard/Reduced [2% less than standard]) and 2) BA (1.0 × 106 CFU/g of feed) supplementation (+/−). After inducing NE infection, blood samples were taken on d 16 for uric acid evaluation, and cecal samples were collected for bacterial enumeration. In both studies, ileal digesta was collected on d 35 for nutrient digestibility evaluation. In study 1, the NE challenge reduced body weight gain (BWG), supressed feed conversion ratio (FCR) and serum uric acid levels (P < 0.001). Supplementation of BA increased BWG (P < 0.001) and reduced FCR (P = 0.043) across dietary treatments, regardless of challenge. Bacillus (P = 0.030) and Ruminococcus (P = 0.029) genomic DNA copy numbers and concentration of butyrate (P = 0.017) were higher in birds fed the diets supplemented with BA. In study 2, reduced protein (RCP) diets decreased BWG (P = 0.010) and uric acid levels in serum (P < 0.001). Supplementation of BA improved BWG (P = 0.001) and FCR (P = 0.005) and increased Ruminococcus numbers (P = 0.018) and butyrate concentration (P = 0.033) in the ceca, regardless of dietary CP level. Further, addition of BA reduced Clostridium perfringens numbers only in birds fed with RCP diets (P = 0.039). At d 35, BA supplemented diets showed higher apparent ileal digestibility of cystine (P = 0.013), valine (P = 0.020), and lysine (P = 0.014). In conclusion, this study suggests positive effects of BA supplementation in broiler diets via modulating gut microflora and improving nutrient uptake.  相似文献   
133.
Tropical Animal Health and Production - The emergence of tick-borne diseases has been reported as a serious problem in public health worldwide and many aspects of its epidemiology and effects on...  相似文献   
134.
The effects of doses CTL (0 mg), 30, 300 and 3000 mg/L of extracts from Stryphnodendron adstringens (Mart.) Coville (SA), Lafoensia pacari A. St.-Hil (LP), Copaifera spp. (CO) and Pterodon emarginatus Vogel (PE) on ruminal fermentation were investigated in eight experiments conducted in randomized complete block designs. The in vitro system contained four fermentation vessels. Each treatment was allocated in one vessel in each run. Incubation was run four and five times with diets 50:50 and 10:90 (roughage to concentrate ratio) respectively. Incubation vessel was the experimental unit, and each incubation run was a block. All plant extracts negatively affected DM degradation at 3000 mg/L. In diet 50:50, SA-3000 increased the molar proportion of propionate (p < 0.05), yet it decreased the concentration of fermentation products (p < 0.05); LP-300 reduced ruminal ammonia nitrogen (NH3-N; 98 vs. 120 mg/dl for LP-300 and average of CTL and LP-30, respectively) and isobutyrate (p < 0.05); CO-300 reduced (p < 0.05) NH3-N (98 vs. 123 mg/dl for CO-300 and average of CTL and CO-30, respectively); and P. emarginatus had no positive effects on rumen fermentation (p > 0.05). In diet 10:90, SA-300 reduced (p < 0.001) NH3-N and total volatile fatty acids (VFA); LP-30 increased (p < 0.05) total VFA (85 vs. 63 mM for LP-30 and CTL, respectively), molar proportions of acetate and propionate, and had lower C2:C3 than CTL (3.6 vs. 4.3, respectively); CO-300 decreased acetate and increased propionate, reducing C2:C3 (p < 0.001; 2.8 vs. 3.6 for CO-300 and average of other doses, respectively); PE-30 and PE-300 reduced NH3-N by 14% and increased total VFA by 29% compared with CTL (p < 0.05). Further in vivo investigations may consider L. pacari (LP-30), Copaifera spp. (CO-300) oleoresin and P. emarginatus oleoresin (PE-30 and PE-300) in diets with high inclusion of concentrate.  相似文献   
135.
ABSTRACT

The application of alternative and sustainable soil correctives to increase soil pH in sowing furrows can promote yield increases in soybean crops. The aim of this study was to characterize two different soil corrective sources in granular and powder forms and to evaluate the agronomic efficiency of their complementary application in a sowing furrow of a soybean crop. Two experiments were conducted. Regarding the first experiment, there were 5 treatments: control, biogenic lime powder, biogenic granular lime, common lime powder, and common granular lime. All applications were performed in a seeding furrow at a dose of 16 kg ha?1. The experiment was carried out in randomized blocks with five replicates. The second experiment involved the characterization of the sources and their forms by means of X-ray diffraction, total chemical analysis and neutralization power. The results showed that in comparison to the control, the application of correctives to increase soil pH in the sowing furrow promoted significantly higher growth and greater soybean yield, although the sources did not differ from each other. The soil pH corrective application in the sowing furrow was important for dissolution in the soil and consequently soybean yield. The neutralizing capacities of the correctives for all the granulometries tested were similar. Therefore, applying these soil pH correctives in granular or powder forms in sowing furrows might be an additional management alternative.  相似文献   
136.
Knowledge of the traits present in plant populations of a species is essential to carry out selection and breeding. The objective of the present study was to estimate the genetic parameters and correlate genetically and phenotypically the variables rubber yield, annual trunk girth increase, number of latex vessel rings and bark thickness in early measurement cycles. A total of 22 rubber tree progenies (Hevea brasiliensis) were assessed in three locations during three early measurement cycles. The bark thickness variable correlated significantly for the three increase measurements made in the locations of Jaú, Pindorama and Votuporanga. The progeny mean based joint hereditability showed mean values greater than individual plants and within progeny plants of 0.848, 0.286 and 0.242, respectively. The variables annual trunk girth increase and bark thickness are genetically correlated variables. Rubber yield is correlated genetically with bark thickness that permits simultaneous selection for the two characteristics. The early measurement cycles were efficacious for finding genetic variability among the genotypes.  相似文献   
137.
138.
In Brazil, chemical control is one of the main tools to manage insect pests in wheat. However, this kind of management can impair the biological control provided by the predators Chrysoperla externa and Eriopis connexa. The present study evaluated the side effects on C. externa and E. connexa of 15 insecticides registered for wheat. Insecticides were sprayed on eggs and pupae via Potter tower at the maximum recommended dose. We evaluated the viability of eggs and pupae as well as the sub-lethal effects on fecundity and fertility of the adults emerged from treated pupae. The insecticides were classified according to the scale of toxicity proposed by IOBC. Regarding the eggs, the insecticide etofenprox was classified as slightly harmful (class 2) to C. externa. Imidacloprid + beta-cyfluthrin, diflubenzuron WG, thiamethoxam + lambda-cyhalothrin A and B, gamma-cyhalothrin, and etofenprox were also classified as slightly harmful (class 2) to E. connexa, while methomyl was classified as moderately harmful (class 3) for the eggs of the predator. The insecticide imidacloprid + beta-cyfluthrin was considered slightly harmful (class 2) to pupae of C. externa, while imidacloprid + beta-cyfluthrin, thiamethoxam + lambda-cyhalothrin A and B, and lufenuron were classified as slightly harmful (class 2) to the pupae of E. connexa. The insecticides beta-cyfluthrin, diflubenzuron SC, lambda-cyhalothrin, permethrin, thiamethoxam, triflumuron, and zeta-cypermethrin were harmless to eggs and pupae of both predators and should therefore be prioritized in the control of insect pests in wheat, thus preserving the natural biological control provided by C. externa and E. connexa.  相似文献   
139.
The juçara fruits (Euterpe edulis Martius), native to the Atlantic Forest, are rich in anthocyanins. To preserve the anthocyanins in juçara fruit pulp, this study aimed to evaluate the effectiveness of microencapsulation by spray drying and freeze drying with maltodextrin (dextrose equivalent 16.5 to 19.5) and gum arabic in different proportions. The obtained microparticles were characterized by quantifying the total polyphenol and anthocyanin contents, by performing differential scanning calorimetry, thermogravimetry, and infrared spectroscopy and by using scanning electron microscopy to analyze the morphology of the particles. The total amount of polyphenols in the fruit pulp was 750?±?16.7 mg GAE/100 g of the freeze-dried sample. The total anthocyanins in the fruit pulp was 181.25?±?5.36 (mg/100 g). The microparticles were formed by employing maltodextrin and gum arabic in a 1:1 proportion as the polymeric matrix; the mixtures of pulp and polymeric matrix were prepared in proportions of 2:3 and 2:1, preserving up to 83.69% of the anthocyanin content. Lyophilization of the 2:1 mixture resulted in an anthocyanin content of 116.89?±?4.43 (mg/100 g), whereas lyophilization of the 2:3 mixture resulted in 151.68?±?1.39 (mg/100 g) anthocyanin content, which did not differ from the value obtained by spray drying the 2:3 mixture (150.76?±?5.79 (mg/100 g)). Thermal analyses showed that the microparticles obtained by freeze drying at a ratio of 2:3 presented greater resistance to degradation with increasing temperature. The incorporation of the pulp in the polymeric matrix was demonstrated by IR analyses. Microparticles obtained by freeze drying showed the formation of various-sized flakes, whereas those obtained by spray drying were spherical in shape. Microencapsulation is a possible alternative for improving the stability of the anthocyanins in this fruit.  相似文献   
140.
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