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11.
Dannylo O. Sousa Hanne H. Hansen Ola Hallin Luiz G. Nussio Elisabet Nadeau 《Grass and Forage Science》2020,75(1):76-85
Red clover (Trifolium pratense) and lucerne (Medicago sativa) are among the most common legume species used for ruminant feeding systems. Besides the greater nutritive quality and first-year ley yield compared to lucerne, red clover decreases its yield over the years. However, under unfavourable soil conditions the persistency of lucerne can be compromised, not performing as expected. This study compared yield and chemical composition of eight lucerne cultivars and one tetraploid red clover cultivar, with similar growth capacity as lucerne, replicated over two years. In the second year, four lucerne cultivars and the red clover cultivar were analysed for crude protein (CP) fractions, dry matter and neutral detergent fibre (NDF) digestibility. A randomized block design was used with three field blocks per cultivar for the multiple comparisons within each year. There were differences in DM yield, concentrations of CP and NDF and CP fractions among the lucerne cultivars, but the differences were inconsistent between years and between growth cycles within year. The red clover cultivar had lower CP and NDF concentrations than a majority of the lucerne cultivars, and greater in vitro organic matter digestibility compared to all of the lucerne cultivars. Also, the red clover cultivar had greater rumen undegradable-to-degradable CP ratio but confirmed its lower yield persistency compared to the lucerne cultivars. 相似文献
12.
David M. Jaramillo José C. B. Dubeux Jr Joao M. B. Vendramini Luana M. D. Queiroz Erick R. S. Santos Martin Ruiz-Moreno Liza Garcia Daciele Sousa de Abreu Lucas Ramos de Miranda Michelle Cristina Fernando de Siqueira 《Grass and Forage Science》2020,75(2):153-158
Nitrogen fertilization is a common practice for sustaining forage production in forage systems in southeastern United States. Warm-season annual legumes may be an alternative forage to warm-season perennial grasses that do not require N fertilization. Sunn hemp (Crotalaria juncea L.) is a fast-growing, warm-season annual legume native to India and Pakistan. The objective of this 2-year study was to assess the herbage accumulation (HA), atmospheric N2 fixation (ANF) and nutritive value of sunn hemp. Treatments were the factorial arrangement of two sunn hemp cultivars (“Crescent Sun” and “Blue Leaf”), three seeding rates (17, 28 and 39 kg seed/ha) and seed inoculation (inoculated or non-inoculated seeds), distributed in a randomized complete block design with four replicates. Crescent sun had greater HA (3,218 vs. 1764 kg DM/ha) and ANF (41 vs. 25 kg N/ha). Blue leaf had greater crude protein (CP) (188 vs. 176 g/kg) and in vitro digestible organic matter (IVDOM) concentrations (564 vs. 531 g/kg) than crescent sun. Non-inoculated seed had greater CP than inoculated seed, 188 and 177 g/kg, respectively, and inoculation did not affect HA. Intermediate seeding rate (28 kg/ha) decreased HA (2002 kg DM/ha), while HA from high and low seeding rates (17 and 39 kg/ha, respectively) did not differ (2,863 and 2,615 kg DM/ha respectively). Planting non-inoculated crescent sun at 17 kg/ha seeding rate is a feasible management practice to produce sunn hemp in subtropical regions; however, inoculation should always be recommended for proper establishment. 相似文献
13.
Canada N Meireles CS Rocha A Sousa S Thompson G Dubey JP Romand S Thulliez P Correia da Costa JM 《Veterinary parasitology》2002,110(1-2):11-15
Neospora caninum was isolated from the brain of an aborted 4-month-old fetus from a dairy cow herd with endemic neosporosis in Porto, Portugal. The fetal brain homogenate was inoculated interperitoneally first into outbred Swiss Webster mice given dexamethasone and then the peritoneal exudates from these mice was co-inoculated with mouse sarcoma cells in the peritoneal cavity of mice given dexamethasone. N. caninum tachyzoites were seen in peritoneal exudate of the second passage. Tachyzoites from the peritoneal exudate reacted positively with anti-N. caninum antibodies and not with anti-Toxoplasma gondii antibodies and contained N. caninum specific DNA. This Portuguese isolate of N. caninum has been successfully maintained in cell culture. The dam of the aborted fetus had an antibody titer of 1:10240 in the Neospora agglutination test (NAT). Antibodies to N. caninum were found in 76 of 106 cows from this herd in titers of 1:40 in 31, 1:80 in 22, > or =1:160 or more in 23 in the Neospora agglutination test. This is the first isolation of a viable N. caninum-like parasite from any host in Portugal. 相似文献
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Fabrício de Oliveira Reis Eliemar Campostrini Elias Fernandes de Sousa Marcelo Gabetto e Silva 《Scientia Horticulturae》2006
In papaya plants a study to quantify the water flow through the trunk is important for to promote a good water management in commercial orchard. The objective was to study the relationship between water flow through the trunk and temperature measurements determined by probes inserted in the papaya plant stem in laboratory. In addition, was possible to study the relationship between sap flow and instantaneous gas exchange in field conditions. We constructed an instrument that maintained a stable water flux through a 0.30 m stem section with a constant pressure, simulating the xylem sap flow through the stem. Water flux was adjusted by varying pressure of water in the stem section. The mathematical model used to fit the relation between K (Granier heat coefficient) values and sap flow density was the exponential model: u = 0.5511 × K1.9104. Field studies was conducted in a commercial orchard located in North of the State of Rio de Janeiro, with 12 plants in October 2002, and eight plants in January 2003. We verified that instantaneous transpiration, measured by a portable system of gas exchange (porometry), presented a good (R2 = 0.75) positive relationship with xylem sap flow. Estimates of papaya sap flow can be obtained by scaling portable photosynthesis system measurements with exposed leaves, however the relationship is non-linear in higher instantaneous transpiration rates. The causes of the non-linear relationship in higher transpiration are discussed. In addition, was possible to obtain a good (R2 = 0.76) relationship between net photosynthesis rate and xylem sap flow in papaya field-grown. 相似文献
16.
Sousa Larissa Nascimento Batista Samira Pereira Silva Samara Santos da Silva Rômulo Fylipe Sarmento Wlysse Ferreira Mota Rinaldo Aparecido Brasil Arthur Willian Lima Amaku Marcos Feitosa Thais Ferreira Vilela Vinícius Longo Ribeiro 《Veterinary research communications》2022,46(2):507-515
Veterinary Research Communications - This study aimed to describe the transmission of T. gondii in naturally infected goats in the semiarid region of northeastern Brazil, through evaluating the... 相似文献
17.
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
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20.
de Brito ES de Araújo MC Alves RE Carkeet C Clevidence BA Novotny JA 《Journal of agricultural and food chemistry》2007,55(23):9389-9394
Many tropical fruits are rich in anthocyanins, though limited information is available about the characterization and quantification of these anthocyanins. The identification and quantification of anthocyanin pigments in four tropical fruits were determined by HPLC-MS/MS. Fruits studied included acerola (Malphigia emarginata), jussara (Euterpe edulis), jambol?o (Syzygium cumini), and guajiru (Chrysobalanus icaco). All four fruits were found to contain anthocyanin pigments. Anthocyanidin backbones included cyanidin, delphinidin, peonidin, pelargonidin, petunidin, and malvidin. Guajiru contained several acylated forms, while acerola, jussara, and jambol?o contained only nonacylated glycosides. These results demonstrate that these tropical fruits are rich in anthocyanins and that the anthocyanins are widely ranging in anthocyanidin backbone, glycosylation, and acylation. 相似文献