Effect of biofloc technology (BFT) on the early postlarval stage of pink shrimp <Emphasis Type="Italic">Farfantepenaeus paulensis</Emphasis>: growth performance,floc composition and salinity stress tolerance

Biofloc rearing media provides a potential food source for shrimp reared in limited or zero water exchange systems. This culture system is environmentally friendly as it is based on limited water use and minimal effluent is released into the surrounding environment. In this study, we evaluated the survival, growth performance and salinity stress tolerance of pink shrimp Farfantepenaeus paulensis postlarvae reared from PL₁₀ to PL₂₅ in a biofloc technology limited water exchange system. PL (mean ± SD weight and length of 14 ± 10 mg and 8.10 ± 0.7 mm, respectively) were reared in nine 40-L plastic tanks with a stocking density of 10PL/L. Three culture treatments were applied (1) culture in the presence of bioflocs and commercial feed supply (FLOC + CF); (2) culture in the presence of biofloc without feed supply (FLOC) and (3) culture in clear water with feed supply (control). Final biomass and survival were significantly higher in FLOC + CF treatment than the control (P < 0.05), but did not differ from FLOC. PL reared in the FLOC + CF treatment achieved a significantly higher final weight, weight gain and length in comparison with the other two treatments (P < 0.05). No significant difference (P > 0.05) between treatments was found for salinity tolerance over 24 and 48 h durations. The proximate analysis of floc shown high levels of crude protein (30.4%), but low levels of crude lipids (0.5%). The continuous availability of bioflocs had a significant effect on growth and survival of F. paulensis postlarvae cultured in BFT nursery systems.     

Mineral nutrient fluxes in rainfall and throughfall in a lowland Atlantic rainforest in southern Brazil

The ecosystems occurring on dystrophic soils, such as sandy soils, are highly dependent on nutrients from the atmosphere and those cycled by their own biota. Nutrient inputs from rainfall and throughfall were measured between October 2001 and August 2003 in a secondary Atlantic rainforest in southern Brazil. Canopy interception (rainfall minus throughfall) was 17.3% of the annual rainfall of 2,235 mm. Monthly interception ranged from 12 to 31% during the rainiest months (precipitation above 200 mm) and from 1 to 45% during the driest months (precipitation below 50 mm) indicating relatively high variability during this period. The studied site may be susceptible to water stress in this period due to the high permeability of the sandy soil. Approximately 80% of the Ca and Na and 57% of Mg were mainly from rainfall (bulk deposition) whereas the main input source for K was net throughfall (about 78%). Mean annual inputs via throughfall (in kg ha⁻¹) were: 90.6 for Na, 29.1 for K, 7.1 for Ca, and 2.9 for Mg. The highest nutrient inputs occurred during the rainy season. Na fluxes were relatively high, while K, Ca, and Mg inputs were low, compared with other tropical and subtropical forests. Information on nutrient fluxes for different forest ecosystems are fundamental for building up a database that can give support to environmental diagnosis, to forest management, and to conservation and restoration techniques.     

Assessment of genetic relatedness of the genera Ananas and Pseudananas confirmed by RAPD markers

Genetic relationships among 18 accessions, including 16 of Ananas and two of Pseudananas, were investigated using RAPD molecular markers. The procedure for DNA extraction was adapted from the method of Dellaporta et al. (1983) where an incubation in proteinase K and a purification step were included. From the total of 148 markers scored,132 (89.2%) were polymorphic. The similarity matrix was used for cluster analysis. The phenogram developed from the RAPD bands showed that for most of the cases, the accessions within a species grouped together. Nevertheless, a moderate infraspecific genetic variation was observed. For example, DNA data grouped all A. comosus accessions with a mean similarity coefficient of 0.85. Comparable results were obtained with all other species investigated. The highest genetic divergence was found withinA. lucidus where the mean similarity coefficient among accessions was0.75. A similar level of genetic polymorphism was observed among species,therefore, a definition about which species were involved in the constitution of A. comosus genotypes was not possible. These results agree with the breeders standpoint suggesting that all Ananas species belong to the primary gene pool of pineapple. This revised version was published online in July 2006 with corrections to the Cover Date.     

Inheritance of angular leaf spot resistance in common bean line BAT 332 and identification of RAPD markers linked to the resistance gene

The existence of genetic variability for angular leaf spot (ALS) resistance in the common bean germplasm allows the development of breeding lines resistant to this disease. The BAT 332 line is an important resistance source to common bean ALS. In this work we determined the inheritance pattern and identified RAPD markers linked to a resistance gene present in BAT 332. Populations F₁, F₂,BCs and BCr derived from crosses between BAT 332 and cultivar Rudá were used. Rudá is a commercial cultivar with carioca type grains and susceptible to ALS. The resistance of BAT 332 to race 61.41 of the pathogen was confirmed. Segregation analysis of the plants indicated that a single dominant gene confers resistance. For identification of RAPD markers linked to the resistance gene, bulk segregant analysis (BSA) was used. Two RAPD markers,OPAA07₉₅₀ and OPAO12₉₅₀, linked in coupling phase at 5.10 and 5.83 cM of this gene, respectively, were identified. These molecular markers are important for common bean breeders and geneticists as source of genetic information and for marker assisted selection in breeding programs. This revised version was published online in July 2006 with corrections to the Cover Date.     

Effect of a Bowman-Birk proteinase inhibitor from Phaseolus coccineus on Hypothenemus hampei gut proteinases in vitro

The coffee berry borer, Hypothenemus hampei (Ferrari), is an important devastating coffee pest worldwide. Both trypsin and chymotrypsin enzyme activities from H. hampei larval midgut can be inactivated by proteinaceous enzyme-inhibitors. A serine proteinase inhibitor belonging to the Bowman-Birk class was purified from a wild accession of Phaseolus coccineus L. seeds. The inhibitor (PcBBI1) is a cysteine-rich protein that is heat-stable at alkaline pH. MALDI-TOF/MS analysis showed that PcBBI1 occurs in seeds as a monomer (8689 Da) or dimer (17,378 Da). Using in vitro inhibition assays, it was found that PcBBI1 has a high inhibitory activity against H. hampei trypsin-like enzymes, bovine pancreatic chymotrypsin, and trypsin. According to this, PcBBI1 could be a promising tool to make genetically modified coffee with resistance to coffee berry borer.     

Evaluation of hematological,biochemical and oxidative stress profile in calves under propofol anesthesia

Veterinary Research Communications - Propofol is a widely used drug in veterinary medicine to induce anesthesia; as well as the chosen compound for protocols of intravenous anesthesia. The present...     

Genetic and functional leaf traits variability of Quercus laurina along an oak diversity gradient in Mexico

The ecological literature has documented the effects of plant hybridization on phenotypic variation, and dominant, intermediate, or novel morphological, chemical and physiological traits in hybrids. It is important to understand the ecological consequences of hybridization by evaluating their impact on phenotypic expression of functional traits. We evaluated the relationship between genetic diversity of Quercus laurina and functional foliar traits along an oak diversity gradient. We selected five study sites that represent an oak diversity gradient where Q. laurina is present. Using chloroplast and nuclear microsatellites, we evaluated genetic diversity, measured functional foliar traits of Q. laurina in each site and assessed the effects of local climate variables on the oak community and functional traits. We found a greater abundance of Q. laurina in all study sites. We did not find a relationship between the number of accompanying red oak species and the population genetic diversity in Q. laurina, but higher genetic diversity was found in all study sites in comparison with European oak species. Sites with more oak species had more variation of foliar functional traits. Our results do not support the hypothesis that predicts higher levels of genetic diversity of Q. laurina in communities with greater oak diversity from the same section, but we demonstrated an increase in the foliar functional traits of Q. laurina associated with oak richness and climate variables. We highlight the need to consider environmental and ecological variables linkages as regulatory mechanisms of the phenotypic plasticity expressed in changes of some functional attributes of oaks.

     

Spatiotemporal distribution of floral resources in a Brazilian city: Implications for the maintenance of pollinators,especially bees

Cities provide resources for the animals that live in them or their surroundings. There has been an increase in the number of ecological studies in urban areas, including interactions between plants and bees. Bees are pollinators that provide a vital ecosystem service to crops and wild plants. We assessed plant community structure in the campus of Universidade de São Paulo in Ribeirão Preto, Brazil, included in the neotropical Atlantic Forest biome, focusing on floristic composition, pollination syndromes, flowering phenology, and spatiotemporal distribution of floral resources for bees. Currently, the city is surrounded by sugar cane plantations. Once a month, from April 2011 to March 2012, we sampled plant species and individuals in bloom in an area with 500 m radius from the bee-rearing facilities of Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP), totaling 78 hectares. We sampled 289 plant species of 73 families; Leguminosae was the richest family. Plants pollinated by bees predominated (67%), followed by plants pollinated by hummingbirds (18%). Melittophilous species flowered throughout the year and, hence, food availability for bees was continuous. The flowering of plant individuals that provided pollen, nectar, and floral oil was seasonal in all vegetation (except for nectar in shrubs), with peaks in resource availability in the transition from the dry to the rainy season, and also in the rainy season. Our results show that the campus is able to maintain bee populations amid a monoculture matrix, acting as a refuge. In addition, it provides a list of several attractive native plants to different pollinator groups, coupled with a phenogram, that can be used in the design and planning of urban areas.     

Historical and contemporary habitat use of sperm whales around the Galápagos Archipelago: Implications for conservation

1. Sperm whales have occupied the waters off the Galápagos Islands, Ecuador, for at least the past 200 years. During the 19^th century, they were the target of intensive whaling that severely depleted the population. In recent times, after commercial whaling ended, sperm whales in the region remain vulnerable to multiple threats, especially potential entanglement in fishing gear, which may hinder their ability to recover from the whaling era.
2. As a highly mobile, long-lived species, long-term analysis of the habitat use of sperm whales is necessary to establish effective conservation and management strategies. Here, contemporary (1985–2014) and historical (1830–1850) sperm whale habitat use off the Galápagos Islands was analysed and contrasted to the extent of the Galápagos Marine Reserve (GMR). Contemporary habitat use and its variability over time were modelled as a function of geographic, oceanographic, and topographic variables using generalized additive models.
3. The fine-scale habitat (<50 km) used by sperm whales was associated with topographic (i.e. depth and slope) and oceanographic characteristics (i.e. relative sea surface temperature and standard deviation of sea surface temperature), but these preferences varied over time.
4. While historical and contemporary data indicate that sperm whale habitat primarily occurred within the boundaries of the GMR, in recent years, whales were found up to 30.1% of the time outside the GMR, potentially overlapping with commercial fisheries operating in the area.
5. The dynamic nature of the relationship of this nomadic species with its habitat highlights the need of large-scale conservation efforts across the Eastern Tropical Pacific region, including the wide-scale enforcement of regulations requiring the use of Automatic Identification System in fishing vessels, the promotion of on-board fisheries observer programmes, the development of adaptive management strategies, and international collaboration to identify and mitigate threats.

     

Leukocyte response and phagocytic activity in Nile tilapia experimentally infected with <Emphasis Type="Italic">Enterococcus</Emphasis> sp.

This study evaluated the total and differential leukocyte counting and the phagocytic activity in Nile tilapia Oreochromis niloticus experimentally injected with Enterococcus sp. in the swim bladder. Fish were distributed in four treatments in triplicates of non-injected fish, fish injected with 1 ml of sterile saline solution 0.65%, and fish injected with 1 × 10³ and 1 × 10⁶ colony-forming units (CFU) of Enterococcus diluted in 1 ml sterile saline. Twenty-four hours after injection, the fish were anesthetized and the blood collected for white blood cell (WBC) counts, differential counting of WBC, and phagocytic activity of blood leukocytes. The increased numbers of WBC and lymphocytes were followed by decreased number of monocyte after infection. The percentages of phagocytic activities in the blood were 55.3 and 55.9%, respectively, in tilapia injected with 1 × 10³ and 1 × 10⁶ CFU/ml.