How planktonic microcrustaceans respond to environment and affect ecosystem: a functional trait perspective     

Sodré  Elder de Oliveira  Bozelli  Reinaldo Luiz 《International Aquatic Research》2019,11(3):207-223

International Aquatic Research - Functional traits are ecologically relevant characteristics of species. They are relevant to community structuring in face of environmental drivers (response...  相似文献   

Effect of the Lactiplantibacillus plantarum and Lentilactobacillus buchneri on corn and sorghum silage quality and sheep energy partition under tropical conditions     

Frederico Patrus Ananias de Assis Pires  Thierry Ribeiro Tomich  Luiz Gustavo Ribeiro Pereira  Fernanda Samarini Machado  Mariana Magalhães Campos  Alan Figueiredo de Oliveira  Guilherme Lobato Menezes  Rafael Araújo de Menezes  Pamella Grossi de Sousa  Diogo Gonzaga Jayme  Lúcio Carlos Gonçalves 《Grass and Forage Science》2023,78(1):224-235

This study aimed to evaluate the silage quality, ingestive behaviour, and sheep energy partition fed corn and sorghum silages, with or without inoculation with Lactiplantibacillus plantarum and Lentilactobacillus buchneri. Whole plants of one dent corn hybrid (DCS), one flint corn hybrid (FCS), and one forage sorghum hybrid (SS) were ensiled with or without an inoculant containing L. plantarum and L. buchneri (4 × 10⁵ CFU g⁻¹), totalling six treatments (3 × 2 factorial scheme). The treatments were ensiled in metal drums with 200 L capacity. The lactic acid concentrations in the inoculated FCS and DCS were higher by 13.4% and 12.8%, respectively, than those in the non-inoculated plants. In contrast, the lactic acid concentration in the inoculated SS was 23.1% lower than that in the non-inoculated SS. Furthermore, there were differences in pH and acetic acid concentrations only in SS, which were 2.3% and 45.2% higher, respectively, in inoculated silage than in non-inoculated silage. In inoculated DCS and SS, propionic acid concentrations were 1.7 times higher (for both silages), and 1-propanol was 3.7 and 1.8 times higher compared than those in non-inoculated silages. There was a main effect of the inoculant on 1,2-propanediol concentrations, which were 37.5% higher in inoculated silages than in non-inoculated silages. However, ingestive behaviour, heat and methane production, and silage net energy concentrations were not affected by inoculant use. Fermentative modifications caused by inoculation with L. plantarum and L. buchneri in whole plant corn or sorghum silage did not modify sheep energy partition.  相似文献   

Regional and sectorial impacts of the COVID-19 pandemic in Sergipe,Brazil     

Luiz Carlos De Santana Ribeiro  Morais Correia De Melo Assunção Laudenor  Luiz Carlos Day Gama  Amir B. Ferreira Neto 《Growth and change》2023,54(3):674-693

This paper aims at estimating the regional and sectoral impacts of the Covid-19 pandemic in the state of Sergipe, Brazil in 2020. We use an input-output model with partial hypothetical extraction. The main results suggest a significant reduction in economic activity in the state, particularly in the Transport and Industry sectors. On the other hand, the Real estate and Food and Accommodation sectors have a greater capacity for recovery with the introduction of an emergency aid program. The municipalities with the largest absolute impact on gross domestic product are Aracaju, Canindé de São Francisco and Nossa Senhora do Socorro, two of them located in the metropolitan area of Aracaju.  相似文献   

Delaying establishment of controlled atmosphere or CO₂ exposure reduces ‘Fuji’ apple CO₂ injury without excessive fruit quality loss     

Luiz Argenta  Xuetong Fan  James Mattheis   《Postharvest Biology and Technology》2000,20(3):221-229

Storage of ‘Fuji’ apple fruit in a high CO₂ (3 kPa) and low O₂ (1.5 kPa) controlled atmosphere (CA) reduced firmness and titratable acidity (TA) loss during long term storage. This CA environment also induced development of internal CO₂-injury (brown-heart) and slowed the disappearance of watercore. The symptoms of internal CO₂-injury were first detected 15 days after CA establishment and the severity increased during the first 4 months of CA-storage. Delaying establishment of CA conditions for 2–12 weeks significantly reduced the severity of CO₂-injury. Delaying CO₂ accumulation to 3 kPa for 1–4 months during CA (1.5 kPa O₂+0.05 kPa CO₂) storage also reduced development of CO₂-injury symptoms. Delaying CA or CO₂ accumulation resulted in lower firmness and TA compared to establishment of CA within 72 h of harvest. However, the delay treatments did result in firmness and TA that were significantly higher compared to values for fruit stored in air. The incidence and severity of senescent injuries (flesh browning and core flush) detected during the late period of storage were greater in air- than CA-stored fruit. The results indicate the susceptibility of ‘Fuji’ apples to CO₂-injury is highest during the first weeks of storage after harvest. Delaying establishment of CA or exposure to elevated CO₂ after harvest may be a practical strategy to reduce CO₂-injury while maintaining other important quality attributes at acceptable levels.  相似文献   

Cross-reaction of tick salivary antigens in the Boophilus microplus-cattle system   总被引：1，自引：0，他引：1  

Norma Vollmer Labarthe  José Oscar Remião  Ana Maria Sacco  Luiz Carlos Maia 《Veterinary parasitology》1985,17(3):259-263

Calves were immunized with Boophilus microplus saliva, filtered through Millipore membranes, in Freund's complete adjuvant. Serum samples were tested by passive hemagglutination against Babesia bigemina, Anaplasma marginale, B. microplus larvae extract, Stomoxys calcitrans extract and B. microplus saliva. After immunization, titers to saliva, larval tick-extract and to S. calcitrans were increased. The challenge with live tick larvae enhanced the formation of antibodies against larva extract, fly extract and tick saliva, which supports the idea that under natural controlled conditions this cross-reactivity could occur.  相似文献   

Riparian coverage affects diets of characids in neotropical streams     

Anderson Ferreira  Felipe R. de Paula  Silvio F. de Barros Ferraz  Pedro Gerhard  Elaine A. L. Kashiwaqui  José E. P. Cyrino  Luiz A. Martinelli 《Ecology of Freshwater Fish》2012,21(1):12-22

Abstract – Aquatic ecosystems are influenced by the surrounding terrestrial environment. This work studied the influence of vegetation of riparian zones on the feeding patterns of two nektonic characids, Astyanax paranae and Bryconamericus iheringii, in a basin surrounded by an agricultural area. Nine streams within the Corumbataí River basin (São Paulo State, Brazil) with varying proportions of adjacent riparian forest (RF) and pastures were set apart in three arbitrary categories: Riparian Forest (>90% RF), Mixed Coverage (banks covered by 30–60% RF; MC) and Pasture (<29% RF, PA); resident characids were sampled in the dry and rainy seasons and evaluated in regard to composition of diets. Astyanax paranae fed on allochthonous food sources in RF and MC, and on autochthonous food sources on PA streams; B. iheringii fed on autochthonous food sources in RF streams and in mixed resources (detritus and sediment) in PA streams. Selection of food source was related to, and altered by, stream channel structure and composition of substratum. Preservation and restoration of native riparian vegetation is key to preservation of resident characids in small streams of this river basin.  相似文献   

Digestive peptidases and proteinases in the midgut gland of the pink shrimp Farfantepenaeus paulensis (Crustacea, Decapoda, Penaeidae)     

Diego Souza Buarque  Patrícia Fernandes Castro  Fábio Marcel Silva Santos  Daniel Lemos  Luiz Bezerra Carvalho Júnior  & Ranilson Souza Bezerra 《Aquaculture Research》2009,40(7):861-870

Proteases from the midgut gland of the Farfantepenaeus paulensis juveniles were assessed. Enzyme activity was determined using protease substrates and inhibitors. The effect of pH, temperature and calcium on proteolytic activity was assayed. Caseinolytic activity was analysed in substrate-sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Trypsin, chymotrypsin and leucine aminopeptidase activity was detected. Proteolytic activity was strongly inhibited by the specific trypsin inhibitors. Tosyl-phenylalanine chloromethyl ketone inhibited 59.3% of chymotrypsin activity. The greatest trypsin-like activity occurred at pH 8.0 and 45 °C. Chymotrypsin-like activity reached maximal values at alkaline pH (7.2–9.0) and 55 °C. CaCl₂ did not increase trypsin-like activity, but rather inhibited it at concentrations of 30 (20%), 50 (30%) and 100 mM (50%). The substrate-SDS-PAGE zymogram revealed eight proteinase bands. Two possibly thermal-resistant (85 °C, 30 min) chymotrypsin isoforms were found, which were inhibited by phenyl-methyl-sulphonyl-fluoride. Aminopeptidase activity of enzyme extracts (Arg, Leu, Lys, Phe and Val) and the recommended concentrations of these essential amino acids in penaeid shrimp diets were positively correlated ( P <0.05). Beause protein digestion involves the combined action of different enzymes, adequate knowledge of shrimp digestion and enzyme characteristics is required for the assessment of the digestive potential of different feed sources and development of in vitro digestibility protocols.  相似文献   

Vaccination strategies with oral booster for surubim hybrid (Pseudoplatystoma corruscans × P. reticulatum) against haemorrhagic septicaemia          下载免费PDF全文

Gabriella do Vale Pereira  Bruno Corrêa da Silva  Felipe do Nascimento Vieira  Walter Quadros Seiffert  Thiago Tetsuo Ushizima  José Luiz Pedreira Mouriño  Maurício Laterça Martins 《Aquaculture Research》2015,46(8):1831-1841

This study evaluated the efficiency of differently prepared vaccines against Aeromonas hydrophila in the hybrid surubim (Pseudoplatystoma corruscans × P. reticulatum). Survival and haemato‐immunological parameters were compared between the treatments: non‐vaccinated fish (C); bacterin‐vaccinated fish (B); bacterin plus oral booster vaccinated fish (B+O); bacterin and toxoid‐vaccinated fish (B+T) and bacterin, toxoid and oral booster‐vaccinated fish (B+T+O). Fourteen‐days vaccinated fish from B+O and B+T+O were fed with an oral booster for 4 days. After 1 week, the fish were intraperitoneally challenged with 2 × 10⁸ CFU mL^?1 of A. hydrophila. Fish from the treatment B+T+O showed the lowest cumulative mortality (11.36%) 96 h after challenge, compared with other treatments (22.72–44.04%), and a relative survival of 74%. Serum immunoglobulin in B+T+O fish was higher than in other treatments. All vaccinated fish showed an increased agglutination titre when compared with non‐vaccinated fish, both before and after challenge. Fish fed with oral booster showed an increase in phagocytic percentage before and after challenge. It can be inferred that the oral booster vaccination was efficient in reducing mortality in hybrid surubim by enhancing the response against haemorrhagic septicaemia due to A. hydrophila infection.  相似文献   

Genetic progress during 22 years of black bean improvement     

Luis Cláudio de Faria  Patrícia Guimarães Santos Melo  Helton Santos Pereira  Adriane Wendland  Simone Ferreira Borges  Israel Alexandre Pereira Filho  José Luiz Cabrera Diaz  Marcelo Calgaro  Leonardo Cunha Melo 《Euphytica》2014,199(3):261-272

The common bean breeding program coordinated by Embrapa Arroz e Feijão released 50 new cultivars from 1984 to 2010. The aim of the present study was to estimate genetic progress in terms of seed yield and other agronomic traits achieved by the black-type common bean breeding program in Brazil over the 22-year period from 1985 to 2006. Two types of field experiments were performed to assess genetic progress. In regard to experiments on lines, the three best breeding lines from each of 11 evaluation cycles constituted 33 treatments. These evaluations were made in 20 environments and served to estimate progress in seed yield and seed size because these were the criteria applied in selecting the elite lines. Cultivar evaluations included nine cultivars recommended by Embrapa during the period under investigation, and the evaluations were established in 21 environments. These evaluations served to estimate improvements in reaction to angular leaf spot, plant architecture and tolerance to lodging because cultivars usually exhibit superior phenotypes for such characteristics. Evaluations were performed from 2008 to 2010. Estimated improvement in seed yield was 25.2 kg ha^?1 or 1.1 % per year. Improvements were also found in tolerance to lodging (1.7 % per year) and 100-seed weight (0.65 % per year). There was no significant progress for the plant architecture and resistance to angular leaf spot traits.  相似文献   

Gill denervation eliminates the barostatic reflex in a neotropical teleost,the tambaqui (<Emphasis Type="Italic">Colossoma macropomum</Emphasis>)     

Vinicius Araújo Armelin  Victor Hugo da Silva Braga  Mariana Teodoro Teixeira  Francisco Tadeu Rantin  Luiz Henrique Florindo  Ana Lúcia Kalinin 《Fish physiology and biochemistry》2016,42(4):1213-1224

The baroreflex is one of the most important regulators of cardiovascular homeostasis in vertebrates. It begins with the monitoring of arterial pressure by baroreceptors, which constantly provide the central nervous system with afferent information about the status of this variable. Any change in arterial pressure relative to its normal state triggers autonomic responses, which are characterized by an inversely proportional change in heart rate and systemic vascular resistance and which tend to restore pressure normality. Although the baroreceptors have been located in mammals and other terrestrial vertebrates, their location in fish is still not completely clear and remains quite controversial. Thus, the objective of this study was to locate the baroreceptors in a teleost, the Colossoma macropomum. To do so, the occurrence and efficiency of the baroreflex were both analyzed when this mechanism was induced by pressure imbalancements in intact fish (IN), first-gill-denervated fish (G1), and total-gill-denervated fish (G4). The pressure imbalances were initiated through the administration of the α₁-adrenergic agonist phenylephrine (100 µg kg^?1) and the α₁-adrenergic antagonist prazosin (1 mg kg^?1). The baroreflex responses were then analyzed using an electrocardiogram that allowed for the measurement of the heart rate, the relationship between pre- and post-pharmacological manipulation heart rates, the time required for maximum chronotropic baroreflex response, and total heart rate variability. The results revealed that the barostatic reflex was attenuated in the G1 group and nonexistent in G4 group, findings which indicate that baroreceptors are exclusively located in the gill arches of C. macropomum.  相似文献