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121.
Berta Gonalves Carlos M. Correia Ana Paula Silva Eunice A. Bacelar Alberto Santos Jos M. Moutinho-Pereira 《Scientia Horticulturae》2008,116(4):381-387
Variations in morpho-anatomy, chemical composition, gas exchange and stem water potential (Ψstem) were studied in leaves of Prunus avium L. cultivars with different growth habit: Burlat and Summit (upright, dense canopies), and Van (spreading, open canopy). Light transmittance was highest in Van canopies. Therefore, Van allowed an easier penetration of the visible radiation through the canopy, which improves photosynthetic rates, especially at harvest. Conversely, no differences in Ψstem were found among cultivars. Van showed the highest leaf mass per unit area and variations in this parameter were mainly associated with alterations in leaf thickness than in leaf density. Leaves of Summit and Van were thicker than those of Burlat, mainly due to increased palisade and spongy parenchyma thickness. However, Burlat leaves had the highest palisade/spongy ratio. Total chlorophyll concentration per area and the chlorophyll a/b ratio were always higher in Van leaves than in the other two cultivars. In contrast, Van leaves had the lowest concentrations of soluble carbohydrates and starch. In dense canopies of Summit and Burlat, light reduction caused a notable increase in the relative concentration of total phenols. The above results provide useful information about the biological behaviour of sweet cherry cultivars with open and dense canopies in order to help the agronomical decisions regarding the local environmental conditions and the consumers’ preference. In particular, it is important to manipulate factors such as orchard exposure, row orientation, plant spacing, training system and pruning, which are able to reduce shading in the canopy. 相似文献
122.
Characterization of the LH peak after short and long fixed‐time artificial insemination protocols in sheep raised in the tropics 下载免费PDF全文
Gabriela Azenha Milani Soriano Felipe Rydygier de Ruediger Marilice Zundt Marco Aurélio da Cruz Nobre Gomes Lilian Francisco Arantes de Souza Ines Cristina Giometti Guilherme de Paula Nogueira Gustavo Ricci Zanelli Fabiola Cristiane de Almeida Rego Caliê Castilho 《Animal Science Journal》2018,89(9):1245-1252
The aim of this study was to evaluate the peak in luteinizing hormone (LH) and the pregnancy rate of sheep (Texel × Santa Inês) in the tropics using short‐ (6 days) and long‐term (12 days) progesterone protocols followed by artificial insemination (AI) both in and out of the breeding season. Experiment 1 was conducted within (IN) the breeding season (autumn, n = 36), and experiment 2 was conducted outside (OUT) of the breeding season (spring, n = 43). In each experiment, the sheep were divided into two groups (6 or 12 days) according to the duration of treatment with a single‐use progesterone release vaginal device (CIDR®, Pfizer, São Paulo, SP, Brazil), and blood samples were collected from 10 animals per group every 4 hr to measure the LH and progesterone concentrations. In the spring, the characteristics of the LH peak did not differ between groups; but in the autumn, there were differences between groups at the beginning (G‐6 IN: 36.44 ± 5.46 hr; G‐12 IN: 26.57 ± 4.99 hr) and end of the LH peak (G‐6 IN: 46.22 ± 7.51 hr; G‐12 IN: 34.86 ± 8.86 hr). The results showed alterations in the LH peak during the breeding season only in the sheep undergoing the short‐term protocol. 相似文献
123.
Corrêa AP Dossi AC de Oliveira Vasconcelos R Munari DP de Lima VM 《Veterinary parasitology》2007,143(3-4):267-274
The aims of this study were to evaluate the immunomodulatory role of TGF-β1, IL-10, and INF-γ in spleen and liver extracts and supernatant cultures of white spleen cells from male symptomatic and asymptomatic dogs, naturally infected by Leishmania (Leishmania) chagasi. Thirty dogs from Araçatuba, São Paulo, Brazil, an endemic leishmaniosis area, were selected by positive ELISA serological reaction for Leishmania sp. and divided into two groups: asymptomatic (n = 15) and symptomatic (n = 15) consisting of animals with at least three characteristic signs (fever, dermatitis, lymphoadenopathy, onychogryphosis, weight loss, cachexia, locomotion problems, conjunctivitis, epistaxis, hepatosplenomegaly, edema, and apathy). After euthanasia, spleen and liver fragments were collected for ex vivo quantification of TGF-β1, IL-10, and INF-γ. Naturally active in vitro produced TGF-β1 was also evaluated in spleen cell culture supernatant. Spleen and liver extract of asymptomatic dogs had higher mean TGF-β1 levels than symptomatic dogs. High concentrations of IL-10 were found in spleen, and mainly in liver extract of both groups. Higher INF-γ concentrations were found in spleen extracts of symptomatic dogs, and in liver extracts of asymptomatic dogs. Extract of this cytokine was lower in spleen extract. Although INF-γ is being produced in canine infection, mean levels of TGF-β1 and IL-10 from spleen and liver extracts were quantitatively much higher; suggesting that immune response in both asymptomatic and symptomatic dogs was predominantly type Th2. 相似文献
124.
de la Fuente J Ruybal P Mtshali MS Naranjo V Shuqing L Mangold AJ Rodríguez SD Jiménez R Vicente J Moretta R Torina A Almazán C Mbati PM de Echaide ST Farber M Rosario-Cruz R Gortazar C Kocan KM 《Veterinary microbiology》2007,119(2-4):382-390
Anaplasma marginale is a tick-borne pathogen of cattle that causes the disease bovine anaplasmosis worldwide. Major surface proteins (MSPs) are involved in host-pathogen and tick-pathogen interactions and have been used as markers for the genetic characterization of A. marginale strains and phylogenetic studies. MSP1a is involved in the adhesion and transmission of A. marginale by ticks and varies among geographic strains in the number and sequence of amino-terminal tandem repeats. The aim of this study was to characterize the genetic diversity of A. marginale strains collected from countries in North and South America, Europe, Asia, Africa and Australia, inclusive of all continents. In this study, we characterized 131 strains of A. marginale using 79 MSP1a repeat sequences. These results corroborated the genetic heterogeneity of A. marginale strains in endemic regions worldwide. The phylogenetic analyses of MSP1a repeat sequences did not result in clusters according to the geographic origin of A. marginale strains but provided phylogeographic information. Seventy-eight percent of the MSP1a repeat sequences were present in strains from a single geographic region. Strong (> or =80%) support was found for clusters containing sequences from Italian, Spanish, Chinese, Argentinean and South American strains. The phylogenetic analyses of MSP1a repeat sequences suggested tick-pathogen co-evolution and provided evidence of multiple introductions of A. marginale strains from various geographic locations worldwide. These results contribute to the understanding of the genetic diversity and evolution of A. marginale and tick-pathogen interactions. 相似文献
125.
126.
Broodstock conditioning of the Portuguese oyster (Crassostrea angulata,Lamarck, 1819): influence of different diets 下载免费PDF全文
Catarina Anjos Teresa Baptista Sandra Joaquim Susana Mendes Ana Margarete Matias Paula Moura Tiago Simões Domitília Matias 《Aquaculture Research》2017,48(7):3859-3878
The Portuguese oyster Crassostrea angulata shows great potential in oyster farming. The conservation of pure populations of this species is important for production diversification and biodiversity preservation. In this way, the zootechnological development for seed hatchery production is extremely important. Broodstock conditioning is a key step in the process of rearing bivalves in a hatchery. Many factors regulate the reproductive cycle, being food one of the most important ones. To evaluate the effect of different diets on C. angulata reproductive performance, broodstock were conditioned with different food regimes formulated fundamentally by flagellates (Diet 1 – Pavlova lutheri and Isochrysis galbana clone T‐ISO; Diet 2 – P. lutheri, T‐ISO and Skeletonema costatum) and constituted fundamentally by diatoms (Diet 3 – S. costatum and Chaetoceros calcitrans; Diet 4 – P. lutheri, S. costatum and C. calcitrans). During conditioning, samples of oysters were collected to evaluate condition index, gonadal development and biochemical composition. At the end of the conditioning period, oysters were induced to spawn to evaluate reproductive output (fecundity, fertilization rate and D‐larvae development). The diets had an impact on the gametogenesis process, energy storage and reproductive output performance, being the best results those obtained in broodstock fed with the diatoms‐predominant diets. However, those fed with diets majority flagellates had an unsuccessful performance. Holistic approaches incorporating all results in this study reveal and reinforce the idea that the diatom species used presented the nutritional requirements to C. angulata broodstock, being essential in the conditioning phase. 相似文献
127.
Vanderlúcia F de Paula Luiz C de A Barbosa Antnio J Demuner Dorila Pil‐Veloso Marcelo C Picano 《Pest management science》2000,56(2):168-174
The natural lipophilic amides piperine and piperiline were isolated from Piper nigrum L (Piperaceae). Piperine was hydrolysed into piperic acid (85% yield) which was converted into 16 amides (28–89% yield). The contact toxicity of all synthetic amides, and also that of piperine and piperiline, at the dose 10 µg per insect, was evaluated for the Brazilian economically important insects Ascia monuste orseis Latr, Acanthoscelides obtectus Say, Brevicoryne brassicae L, Protopolybia exigua DeSaus and Cornitermes cumulans Kollar. The results demontrated that the insects have different sensivities to the various amides, with mortality ranging from 0 to 97.5% according to the compound and insect species. © 2000 Society of Chemical Industry 相似文献
128.
Marta Monteiro Carla Sousa Filipe Coutinho Carolina Castro Filipa Fontinha Inês Guerreiro Pedro Pouso Elisabete Matos Patrícia Díaz-Rosales Aires Oliva-Teles Paula Enes Ana Couto 《Marine drugs》2021,19(11)
Marine algae are recognised sources of bioactive compounds that have attracted great interest as nutritional supplements for aquaculture fish. Intensive rearing conditions often expose fish to husbandry-related stressors, rendering fish more susceptible to disease and reducing production yields. The present work evaluated the potential of two marine algae extracts (Fucus vesiculosus and Nannochloropsis gaditana) as nutritional supplements to mitigate stress effects in meagre (Argyrosomus regius) exposed to an acute handling stress (AS). A plant-based diet was used as a control, and three other diets were prepared, which were similar to the control diet but supplemented with 1% of each algal extract or a combination of the two extracts (0.5% each). The effects of supplemented diets on stress biomarkers, antioxidant enzyme activities, and immune response were analysed in fish exposed to AS after 4 weeks of feeding. Supplemented diets did not affect growth performance but the inclusion of F. vesiculosus promoted higher feed efficiency, as compared to the control group. Dietary algal extracts supplementation reduced plasma glucose levels, increased white blood cell counts, and reduced the expression of pro-inflammatory genes when compared with the control. N. gaditana supplementation led to a reduction in hepatic antioxidant enzyme activity and glutathione levels, while F. vesiculosus supplementation increased muscle glutathione reductase activity and reduced lipid peroxidation. These findings support the potential of algal extracts as nutraceuticals in aquafeeds to enhance the ability of fish to cope with husbandry-related stressful conditions and ultimately improve fish health and welfare. 相似文献
129.
Francisco J. Toledo‐Solís Rafael Martínez‐García Manuel Díaz Emyr Saul Pea Marín Maria Paula Di Yorio Paula Gabriela Vissio Carlos Alfonso lvarez‐Gonzlez Miguel Saenz de Rodrigez 《Aquaculture Research》2020,51(7):2913-2925
For the commercial culture of the three‐spot cichlid (Amphilophus trimaculatus), it is important to have available a set of protein and lipid ingredients suitable for feed manufacturing, which allow to optimize the culture at affordable costs. The in vitro digestibility was evaluated with pH‐stat technique, using stomach and intestine multi‐enzymatic extracts from A. trimaculatus juveniles. The digestion of protein ingredients was taken place both in acid and in alkaline conditions, quantifying the total of free amino acids at the end of the hydrolysis, whereas the digestion of lipid ingredients was taken place only in alkaline conditions. The digestive enzymes of this species showed a better affinity to raw materials of animal origin such as beef meal, fish meal and premium chicken meal, which presented better digestibility. The best lipid ingredient that could be used is the fish oil. However, it is possible to use ingredients from the plant sources, such as soy or cereals, and vegetable oils such as olive, corn or soy oil. It is necessary to complement this study in vitro with the digestibility analysis in vivo, in order to determine the inclusion percentages in feeds and costs and therefore to develop an efficient feed formulation for the aquaculture of A. trimaculatus. 相似文献
130.