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21.
Rhaony Gonalves Leite Elider Prates Romanzini Lutti Maneck Delevatti Alvair Hoffmann Adriana Cristina Ferrari Andr Pastori D'Aurea Lauriston Bertelli Fernandes Amanda Prates Oliveira Ricardo Andrade Reis 《Animal Science Journal》2019,90(5):628-636
Organic additives are recently being used in animal diets owing to their ability to control metabolic issues and result in better animal performance. Specifically, the organic additive Fator P® presents an additional advantage that is to cause a lesser greenhouse gas emission. This study evaluated whether Fator P® intake changes ruminal parameters or animal performance of beef cattle. Evaluations were carried out in a feedlot experiment divided into growing (46 days; two diets [control mix—CM and standard mix—SM] and finishing (lasted 83 days; four diets: CM, SM, Fator P® + virginiamycin, and Fator P® alone [FP]) trials. Animal performance study involved 48 animals allocated to 12 collective pens in completely randomized experimental design. Ruminal parameters were evaluated in separate metabolism study developed carried out using individual pen with four steers. During growing trial, FP diet resulted in higher (p < 0.05) dry matter intake (DMI) and ruminating time. In the finishing trial, diets containing Fator P® resulted in higher DMI than obtained with CM. Most of the ruminal parameters did not differ (p > 0.05) among dietary treatments. Therefore, Fator P® represents a viable and safe strategy for supplementation to beef cattle finished using high‐concentrate diet in feedlot systems. 相似文献
22.
Gallo MB Rocha WC da Cunha US Diogo FA da Silva FC Vieira PC Vendramim JD Fernandes JB da Silva MF Batista-Pereira LG 《Pest management science》2006,62(11):1072-1081
The effects of crude extracts, fractions and isolated compounds from Vitex polygama Cham. and Siphoneugena densiflora Berg were evaluated on the development of Spodoptera frugiperda JE Smith, a destructive insect pest of corn and several other crops. The extracts and fractions were incorporated into an artificial diet at 1 mg g(-1) and offered to the insect during its larval stage. Length and viability of larval and pupal stages as well as pupal weight were assessed. Isolated compounds were tested through superficial contamination of the diet at 0.1 mg g(-1). Weight and viability of ten-day-old larvae were determined. Methanolic and hydroalcoholic S. densiflora extracts caused 100% larval mortality, while leaf and fruit hydroalcoholic extracts from V. polygama were the most active. Among the isolated compounds, flavonoids presented the best insecticidal results, and tannins the best larval growth inhibition. 相似文献
23.
Helena M. Amaro Fátima Fernandes Patrícia Valent?o Paula B. Andrade I. Sousa-Pinto F. Xavier Malcata A. Catarina Guedes 《Marine drugs》2015,13(10):6453-6471
Microalgae are well known for their biotechnological potential, namely with regard to bioactive lipidic components—especially carotenoids and polyunsaturated fatty acids (PUFA), well-known for therapeutic applications based on their antioxidant capacity. The aim of this work was to evaluate the influence of four distinct food-grade solvents upon extractability of specific lipidic components, and on the antioxidant capacity exhibited against both synthetic (2,2-diphenyl-1-picrylhydrazyl (DPPH•) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS+•)) and biological reactive species (O2•− and •NO−). A eukaryotic microalga (Scenedesmus obliquus (M2-1)) and a prokaryotic one (Gloeothece sp.) were used as case studies. Concerning total antioxidant capacity, the hexane:isopropanol (3:2) and acetone extracts of Sc. obliquus (M2-1) were the most effective against DPPH• and ABTS+•, respectively. Gloeothece sp. ethanol extracts were the most interesting scavengers of O2•−, probably due the high content of linolenic acid. On the other hand, acetone and hexane:isopropanol (3:2) extracts were the most interesting ones in •NO− assay. Acetone extract exhibited the best results for the ABTS assay, likely associated to its content of carotenoids, in both microalgae. Otherwise, ethanol stood out in PUFA extraction. Therefore, profiles of lipidic components extracted are critical for evaluating the antioxidant performance—which appears to hinge, in particular, on the balance between carotenoids and PUFAs. 相似文献
24.
Sodicity and salinity in a Brazilian Oxisol cultivated with sugarcane irrigated with wastewater 总被引:2,自引:0,他引:2
Rafael Marques Pereira Leal Uwe Herpin Lilian Pittol Firme Célia Regina Montes Adolpho José Melfi 《Agricultural Water Management》2009,96(2):307-316
Changes in soil sodicity-salinity parameters are one of the most characteristic alterations after treated sewage effluent (TSE) irrigation in agro-systems. Considering the importance of these parameters for agricultural management, as well as the economical value of sugarcane for Brazil, the present study aimed at evaluating effects on soil sodicity and salinity under tropical conditions over 16 months of TSE irrigation in a sugarcane plantation at Lins, São Paulo State, Brazil. Soil samplings were carried out in February 2005 (before planting), December 2005 (after 8 months of TSE irrigation) and September 2006 (after 16 months of TSE irrigation) following a complete block design with four treatments and four replicates. Treatments consisted of: (i) control, without TSE irrigation; (ii) T100, T150 and T200, with TSE irrigation supplying 100% (0% surplus, total of 2524 mm), 150% (50% surplus, total of 3832 mm) and 200% (100% surplus, total of 5092 mm) of crop water demand, respectively. Compared to initial soil conditions, at the end of the experiment increases of exchangeable sodium (from 2.4 to 5.9 mmolc kg−1), exchangeable sodium percentage (ESP) (from 8 to 18%), soluble Na (from 1.4 to 4.7 mmol L−1) and sodium adsorption ratio (SAR) of soil solution (from 3.6 to 12.6 (mmol L−1)0.5) were found in the soil profile (0-100 cm) as an average for the irrigated plots due to high SAR of TSE. Associated with the increments were mostly significant increases in clay dispersion rates at depths 0-10, 10-20 and 20-40 cm. Electrical conductivity (EC) of soil solution increased during the TSE irrigation period whereas at the end of the experiment, after short term discontinuation of irrigation and harvest, EC in the topsoil (0-10 and 10-20 cm) decreased compared to the previous samplings. Moreover, despite increasing sodicity over time mainly insignificant differences within the different irrigated treatments were found in December 2005 and September 2006. This suggests that independent of varying irrigation amounts the increasing soil sodicity over time were rather caused by the continuous use of TSE than by its quantity applied. Moreover, also plant productivity showed no significant differences within the TSE irrigated plots. The study indicates that monitoring as well as remediation of soil after TSE irrigation is required for a sustainable TSE use in order to maintain agricultural quality parameters. 相似文献
25.
Shayne P. Bisetto Adriano B. Carregaro André E.S. Nicolai Thais F. Bressan William P. Leal Nathalia V. Xavier Diego F. Leal André F.C. Andrade 《Veterinary anaesthesia and analgesia》2017,44(3):594-599
Objective
To evaluate the effect of hyaluronidase on uptake, duration and speed of elimination of xylazine–tiletamine–zolazepam administered in the subcutaneous fat over the dorsal lumbar region of swine.Study design
Blinded, randomized, crossover study.Animals
Six healthy Landrace/Large White pigs weighing 132 ± 24 kg (mean ± standard deviation).Methods
Animals were administered xylazine (1 mg kg?1) and tiletamine–zolazepam (8 mg kg?1) (control treatment, CON), or xylazine–tiletamine–zolazepam at the same doses with hyaluronidase (400 IU) (treatment HYA). The treatments were administered into the dorsal lumbar adipose tissue, 2.5–3.0 cm laterally from the spinous process of the second lumbar vertebra. The latency, anesthesia and recovery periods were measured. Heart rate, noninvasive systolic, diastolic, and mean arterial pressures, respiratory rate, hemoglobin oxygen saturation and rectal temperature were recorded every 10 minutes for up to 50 minutes.Results
One animal in CON and one animal in HYA were responsive to stimulation and did not allow safe handling. No significant difference was found between treatments for latency (CON 11.3 ± 5.9 minutes, HYA 7.4 ± 5.1 minutes) and anesthesia (CON 53 ± 53 minutes, HYA 49 ± 38 minutes) periods. Recovery period was shorter in HYA (9 ± 6 minutes) than in CON (32 ± 16 minutes) (p < 0.05). Physiological variables were not significantly changed over time and were within accepted normal clinical limits for the species in both treatments.Conclusion and clinical relevance
Hyaluronidase (400 IU) administered into adipose tissue in pigs did not reduce the latency and duration of dissociative anesthesia, but was associated with faster recovery. 相似文献26.
27.
The Forest village scheme was introduced by the Forest Industries Organisation (FIO) of Thailand in 1967 as an attempt to stop further spread of the fast increasing shifting cultivation and deforestation in the country. The underlying princple of the scheme is to relate reforestation with social welfare of the people involved. It is essentially a modification of the traditional taungya method of plantation establishment.The salient aspect of the scheme is to induce the shifting cultivators to settle down in villages where each family is given tenure over a plot of land to construct a house and develop a homegarden around it. The farmers are required to help establish and maintain forest plantations, in which they are permitted to raise agricultural crops during the first three years of its establishment. The farmers are also given free medical and educational facilities, and technical advice on crop and livestock husbandry. They can also earn cash rewards for successful plantation establishment.Although the scheme has not achieved its full target in terms of area covered and number of families settled, it is proving to be a successful method of luring people away from destructive shifting cultivation. The approach is applicable to other countries and regions with similar land-use problems and socio-cultural background.The paper also examines the constraints to the effective working of the scheme, provides some simple suggestions for improving its functioning and identies some of the issues that can easily be tackled by research. 相似文献
28.
Quercus suber L. is an important species producing cork whose wood characteristics have not been investigated a lot. Cork oak wood vessels
are a striking feature and the most abundant wood tissue largely influencing density and permeability. Vessel size and distribution
were studied in approximately 40 year-old and never debarked cork oaks by continuously measuring along the radial direction
in the transverse section of wood discs taken at 1.3 m of height using image analysis techniques. The vessel size increases
with age from 7660 ± 2286 to 21136 ± 6119 μm2, the conductive area from 5.4 ± 2.2 to 11.6 ± 3.9%, and the vessel density remains approximately constant between 5.2 ± 1.5
and 7.3 ± 3.5 vessels/mm2. In comparison with ring-porous and some evergreen oaks, cork oaks show a similar conductive area but smaller vessels. Vessel
architecture is known to play an important role on oaks tolerance to hydric stress, and these cork oak trees were growing
under very harsh edaphoclimatic conditions, not tolerated by other oaks. The well-developed and deep root system allowing
access to constant water supply may contribute to the cork oak’s relatively high conductive area. 相似文献
29.
30.
Primo Anacláudia Alves Araújo Maria Diana Melo Silva Karla da Fonseca Silva Ludmyla Araújo Pereira Graziella de Andrade Carvalho Fernandes Francisco Éden Paiva Pompeu Roberto Cláudio Fernandes Franco Natale William de Souza Henrique Antunes 《Agroforestry Systems》2021,95(8):1459-1464
Agroforestry Systems - The use of native trees in agroecosystems is a promising way to increase litter deposition and nutrient cycling and foster the recovery of degraded areas, especially in... 相似文献