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51.
Silva-Almeida M Carvalho LO Abreu-Silva AL Souza CS Hardoim DJ Calabrese KS 《Veterinary research》2012,43(1):10
ABSTRACT: Leishmania is inoculated, by the bite of an infected sandfly, into the skin of the host, where the promastigotes are phagocyted by dermal macrophages. The dermal region comprises cells and abundant extracellular matrix. Studies show that matrix metalloproteinases play an important role in host defense responses against pathogens in mammals and that their activities lead to the production of antimicrobial peptides. The aim of this study is to evaluate the changes in the distribution of fibronectin and laminin as well as in the elastic system fibres during the course of infection caused by Leishmania amazonensis in mice with distinct genetic backgrounds of susceptibility to this parasite. The results showed that BALB/c presented an enhancement of fibronectin during the course of infection when compared to their control group while the infected or non-infected C3H.He showed a decrease of this protein at end of the experiment. Laminin, on the other hand, remained unaltered in both strains. Also in both BALB/c and C3H.He mice the elastic and elaunin fibres remained unchanged while the oxytalan fibres decreased along the experiment. Ninety days after the infection C3H.He mice had recovered their capacity to produce oxytalan fibres. 相似文献
52.
53.
Lígia Regina Lima Gouvêa Guilherme Augusto Peres Silva Cecília Khusala Verardi André Luis Bombonato de Oliveira Elaine Cristine Piffer Gonçalves Erivaldo José Scaloppi-Junior Mário Luiz Teixeira de Moraes Paulo de Souza Gonçalves 《Euphytica》2013,191(3):365-373
Rubber production in the rubber tree [Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell. Arg.] can be expressed differently in different environments. Thus the objective of the present study was to select productive progenies, stable and responsive in time and among locations. Thirty progenies were assessed by early yield tests at three ages and in three locations. A randomized block design was used with three replications and ten plants per plot, in 3 × 3 m spacing. The procedure of the mixed linear Reml/Blup model—restricted maximum likelihood/best non-biased linear prediction was used in the genetic statistical analyses. In all the individual analyses, the values observed for the progeny average heritability ( $ \hat{h}_{pa}^{2} $ ) were greater than those of the additive effect based on single individuals ( $ \hat{h}_{a}^{2} $ ) and within plot additive ( $ \hat{h}_{ad}^{2} $ ). In the joint analyses in time, there was genotype × test interaction in the three locations. When 20 % of the best progenies were selected the predicted genetic gains were: Colina GG = 24.63 %, Selvíria GG = 13.63 %, and Votuporanga GG = 25.39 %. Two progenies were among the best in the analyses in the time and between locations. In the joint analysis among locations there was only genotype × location interaction in the first early test. In this test, selecting 20 %, the general predicted genetic gain was GG = 25.10 %. Identifying progenies with high and stable yield over time and among locations contributes to the efficiency of the genetic breeding program. The relative performance of the progenies varies depending of the age of early selection test. 相似文献
54.
Luiz Fernando Costa e Silva Sebastião de Campos Valadares Filho Edenio Detmann Polyana Pizzi Rotta Diego Zanetti Faider Alberto Castaño Villadiego Samantha Gusmão Pellizzoni Rafael Moura Guimarães Pereira 《Tropical animal health and production》2013,45(3):795-803
The objectives of this study were to evaluate the dry matter intake (DMI), digestibility, average daily gain (ADG), microbial efficiency, empty body weight (EBW) gain, and body composition of Nellore bulls. Additionally, Nellore bull maturity was estimated, and the prediction equation for DMI, suggested by the Brazilian nutrient requirements system (BR CORTE; Azevêdo et al. 2010), was evaluated. Thirty-three Nellore bulls, with a mean initial weight of 259?±?25 kg and age of 14?±?1 months, were used in this study. Five animals were slaughtered at the beginning of the experiment (control group), and the remaining 28 were divided into 4 groups, each slaughtered at 42-day intervals. Their diet was composed of corn silage and concentrate (55:45). The power model was used to estimate muscle tissue, bone tissue, crude protein (CP), mineral matter (MM), and water present in the empty body, while the exponential model was used to estimate adipose tissue and ether extract (EE) present in the empty body. When expressed in kilograms per day, differences were observed (P?<?0.05) only for the intake of EE and neutral detergent fiber as a function of feedlot time periods. Although there was a difference in relation to nutrient intake, it did not affect (P?>?0.05) digestibility, with the exception of EE digestibility. The equation suggested by BR CORTE correctly estimates the DMI of Nellore bulls. ADG was not affected (P?>?0.05) by time spent in the feedlot. No differences were observed (P?>?0.05) for microbial efficiency; a mean value of 142 g microbial crude protein/kg total digestible nutrients was achieved. The muscle and bone tissues, CP, MM, and water present in the empty body increased as the animal grew, although at a lower rate. The adipose tissue and EE present in the empty body increased their deposition rate when the animal reached its mature weight. Maturity is defined as when an animal reaches 22 % EE in the empty body, which corresponds to 456 kg of EBW in Nellore bulls. Therefore, this study can conclude that the feedlot time period does not affect DMI, nutrient intake, ADG, or microbial efficiency. The equation proposed by BR CORTE (Azevêdo et al. 2010) correctly estimates the DMI of Nellore bulls, which reach maturity when an EBW of 456 kg is attained. 相似文献
55.
Sérgio Luiz Gama Nogueira-Filho Alcester Mendes Ellis Fernanda Kowalski Tavares Selene Siqueira da Cunha Nogueira 《Tropical animal health and production》2013,45(8):1703-1708
Fifteen female adult capybaras, with initial average body weight (BW) of 32.7 (±?5.8) kg, were kept in individual pens to evaluate effect of supplementation of concentrate feed and its supply time on cecotrophy behavior frequency. The animals were allocated in a completely randomized design, with five animals per treatment, receiving three diets: grass only, grass and grain corn offered in a single meal, and grass and grain corn offered in two daily meals; all cecotrophy acts were recorded. Later, in a second experiment, five capybaras received five levels of urea in their diet: 0, 10, 20, 30, and 40 g urea/100 kg BW, replacing soybean meal as true protein source, in a 5?×?5 Latin square design. The animals were weighed and their blood was collected every 2 weeks. The frequency of cecotrophy (Ps?<?0.05) was higher when the capybaras were fed grass only (0.5?±?0.07 acts/h) than when they received grass and corn in a single meal (0.3?±?0.05 acts/h) and grass and corn supplied in separate meals (0.1?±?0.03 acts/h). With increased urea in their diet, the capybaras showed initial signs of chronic intoxication, together with increments in serum urea (r?=?0.87, P?<?0.05) and a decreasing trend in daily weight gain (r?=??0.38, P?=?0.06). Therefore, when including concentrate feeds in capybara diet, these must be mixed with roughage in a single meal to avoid high decrease in the frequency of cecotrophy behavior and increase in dry matter intake. The replacement of soybean meal with urea in capybara diet is not recommended. 相似文献
56.
Carlos Eduardo Camargo Romildo Romualdo Weiss Luiz Ernandes Kozicki Marilia Pastorello Duarte Mario Cesar Garcia Duarte Diego Lunelli Saulo Weber Renata Azevedo de Abreu 《Journal of Equine Veterinary Science》2013
This study aimed to evaluate the effects of certain embryo transfer parameters on the pregnancy rate after equine embryo transfer of the Brazilian Jumper Horse breed. The size, embryonic development stage, embryo quality, and synchronization of ovulation between the donor (n = 120) and recipient (n = 420) were evaluated in 396 embryos. Embryo recovery was performed on Day 6-9 after ovulation (Day 0 = day of ovulation). The recipient mares were chosen on the day of embryo recovery, and the transfers were performed that same day. The embryo size (diameter including envelopes; n = 396) ranged from 150 to 3000 μm; 67.1% measured between 400 and 1199 μm. The embryo size (400-1199 μm vs. ≤399 μm); stage of development (n = 396; blastocyst and expanded blastocyst versus compact morula and early blastocyst); quality (n = 396; grade 1 [excellent]), 2 [good], or 3 [poor]); and synchronization of ovulation between the donor and recipient (0, 1, 2, 3, and 4 days versus −1, 5, and 6 days, respectively) all affected pregnancy rate (P < .05). The pregnancy rate did not differ significantly among transfers performed on Days 0, 1, 2, 3, and 4. In conclusion, embryos measuring 400-1199 μm produced higher pregnancy rates in recipients than embryos measuring 150-399 μm, and blastocysts and expanded blastocysts produced pregnancy more efficiently than morulae and early blastocysts. The embryo quality also affected the pregnancy rate. Synchronization of donor and recipient ovulation to Days 0-4 improved the efficiency of embryo transplant. 相似文献
57.
Luiz Henrique Agra Cavalcante-Silva Ana Carolina de Carvalho Correia José Maria Barbosa-Filho Bagnólia Araújo da Silva Bárbara Viviana de Oliveira Santos Daysianne Pereira de Lira Jéssica Celestino Ferreira Sousa George Emmanuel C. de Miranda Fabiana de Andrade Cavalcante Magna Suzana Alexandre-Moreira 《Marine drugs》2013,11(5):1553-1564
In this work, we investigated the spasmolytic effect of caulerpine, a bisindole alkaloid isolated from marine algae of the Caulerpa genus, on guinea pig ileum. Our findings indicated that caulerpine inhibited phasic contractions induced by carbachol (IC50 = 7.0 ± 1.9 × 10−5 M), histamine (IC50 = 1.3 ± 0.3 × 10−4 M) and serotonin (IC50 = 8.0 ± 1.4 × 10−5 M) in a non-selective manner. Furthermore, caulerpine concentration-dependently inhibited serotonin-induced cumulative contractions (pD′2 = 4.48 ± 0.08), shifting the curves to the right with Emax reduction and slope of 2.44 ± 0.21, suggesting a noncompetitive antagonism pseudo-irreversible. The alkaloid also relaxed the ileum pre-contracted by KCl (EC50 = 9.0 ± 0.9 × 10−5 M) and carbachol (EC50 = 4.6 ± 0.7 × 10−5 M) in a concentration-dependent manner. This effect was probably due to inhibition of Ca2+ influx through voltage-gated calcium channels (CaV), since caulerpine slightly inhibited the CaCl2-induced contractions in depolarizing medium without Ca2+, shifting the curves to the right and with Emax reduction. According to these results, the spasmolytic effect of caulerpine on guinea pig ileum seems to involve inhibition of Ca2+ influx through CaV. However, other mechanisms are not discarded. 相似文献
58.
59.
Adibe Luiz Abdalla Filho Paulo de Mello Tavares Lima Gabriel Zanuto Sakita Tairon Pannunzio Dias e Silva Wilian dos Santos da Costa Raquel Ghini Adibe Luiz Abdalla Marisa de Cssia Piccolo 《Grass and Forage Science》2019,74(4):670-677
Increased atmospheric carbon dioxide (CO2) is a consequence of recent anthropogenic environmental changes, and few studies have evaluated its effects on tropical grasses used in Brazilian pastures, the main feed source for major part of ruminant livestock. This study evaluated forage production, chemical composition, in vitro total gas production and organic matter degradability of Brachiaria brizantha under contrasting CO2 atmospheric conditions in a free air carbon dioxide enrichment (FACE) facility. The forage plants were sown in each of the 12 octagonal rings of the FACE facility: six under ambient atmospheric CO2 concentration of approximately 390 μmol/mol, hereafter referred to as control (CON) plots, and other six rings enriched with pure CO2 flux to achieve a target CO2 concentration of 550 μmol/mol, hereafter called elevated CO2 (eCO2) plots. Soil samples were collected to determine carbon and nitrogen concentrations. After seventy days of sowing, a standardization cutting was performed and then at regular intervals of 21 days the forage was harvested (ten harvest dates) and forwarded to laboratorial analyses. Forage above‐ground biomass production (dry matter (DM): 6,143 vs. 6,554 kg/ha), as well as morphological characteristics (leaves: 71% vs. 68%; stem: 28% vs. 31%), chemical composition (crude protein: 162.9 vs. 161.8; neutral detergent fibre: 663.8 vs. 664.3; acid detergent fibre: 369.5 vs. 381; lignin: 60.1 vs. 64.1 g/kg DM; total C: 45.9 vs. 45.9; total N: 2.8 vs. 2.8; total S: 0.2% vs. 0.2%), organic matter in vitro degradability (573.5 vs. 585.3 g/kg), methane (5.7 vs. 4.3 ml/g DM) and total gas (128.3 vs. 94.5 ml/g DM) production did not differ significantly between CON and eCO2 treatments (p > .05). The results indicated that at least under short‐term enrichment, B. brizantha was not affected by eCO2. 相似文献
60.
Barbosa LC Pereira UA Teixeira RR Maltha CR Fernandes SA Forlani G 《Journal of agricultural and food chemistry》2008,56(20):9434-9440
The [4 + 3] cycloaddition of the proper furans with the oxyallyl cation, generated in situ from 2,4-dibromopentan-3-one, produced a series of 8-oxabicyclo [3.2.1]oct-6-en-3-ones. Exposure of the oxabicycles to ozone afforded the corresponding 8,9,10,11-tetraoxatricyclo[5.2.1.1 (2,6)]undecan-4-ones in variable yields (7-100%). The phytotoxic properties of these ozonides (or 1,2,4-trioxolanes) and their oxabicycle precursors were evaluated as the ability to interfere with the growth of Sorghum bicolor and Cucumis sativus seedlings. Among oxabicycles, the highest inhibitory activity was shown by compounds possessing a alpha,beta-unsaturated carbonyl moiety. A differential sensitivity of the two crops was evident with ozonides. The most active compounds were also tested against the weed species Ipomoea grandifolia and Brachiaria decumbens. To the best of our knowledge, this is the first article describing ozonides as potential herbicides. 相似文献