Polyculture of milkfish (Chanos chanos Forskal), all-male Nile tilapia (Tilapia nilotica) and snakehead (Ophicephalus striatus) in freshwater ponds with supplemental feeding

Results showed that all-male Nile tilapia can be cultured in milkfish ponds without affecting the growth and production of milkfish, at ratios of 1–3 tilapia to 5 milkfish; 2:5 is the optimum ratio.Supplemental feeding with fine rice bran or copra meal at a daily rate of 5% of the biomass increased the net production of milkfish but had no influence on all-male Nile tilapia. Standing crop of about 890 kg/ha in 135 days was obtained in a polyculture system of milkfish, all-male Nile tilapia and snakehead when fed rice bran.     

Extremophiles: photosynthetic systems in a high-altitude saline basin (Altiplano,Chile)

Studies of different hypersaline systems have revealed various types of limitation. We evaluated the phototrophic microbial assemblages over a whole seasonal cycle (wet vs dry) in the Salar de Alconcha, a high-altitude (4250 m altitude) saline basin. Phototrophic microbial communities were obtained from contrasting ecotypes, and examined for the effects of proximity and salinity variations. We also analyzed pigment profiles pointing to photosynthetic activity. While taxonomic diversity was limited to three algal groups (chlorophytes, diatoms, and cyanobacteria) ecological preferences were highly variable. Physical limitations when the photosynthetic system turn drier (maintaining viability and stability) appear to be the most successful adaptation (constrained assemblages) to the extreme condition in the Altiplano. This suggests that phototrophic microorganisms rarely achieve optimal growth, and could only do so when rain events reduce salinity (e.g. austral summer). However, environmental condition over the salt crust (total salt concentration: 119.74 g l^?1) was an important driver to algal biomass. Overall, dominated by Dunaliella salina (≈18,000 cell ml^?1) turning the water into a red–orange colored system (β-carotene); aplanospore cysts were observed only during the driest season (austral winter). Our results suggest specific restrictive environments (e.g. environmental dissimilarity in the physical landscape) for phototrophic microbial colonization in high-altitude saline systems quite dependent upon water availability (system on the edge). The present study is a contribution for a better understanding of both the ecology of extreme environments and polyextremophiles communities (phototrophs) that inhabit them. Active salars are considered to be useful analogs of ancient photosynthetic systems, currently very pressured by groundwater extraction. Thus, altering the volume of water through the basin would have negative consequences on the structure and dynamics of local communities, and also in the stability of ecosystem functions.     

Ascorbic acid requirement and histopathological changes due to its deficiency in juvenile spotted rose snapper Lutjanus guttatus (Steindachner, 1869)

A 13-week feeding trial was conducted to determine the optimal dietary ascorbic acid (AA) requirement of juvenile spotted rose snapper (Lutjanus guttatus). Six experimental diets containing 0, 7, 19, 29, 62 and 250 mg AA equivalent kg^?1 diet, supplied as l-ascorbyl-2-polyphosphate designated as VC0, VC7, VC19, VC29, VC62 and VC250, were fed ad libitum to triplicate groups of 20 juveniles [initial weight (IW) of 8 ± 1.85 g]. Nutrient deficiency resulting in fin erosion, dark skin, desquamation and erratic swimming was observed after 8 weeks in fish fed diets from 0 to 29 mg AA kg^?1. Fish that were fed all diets showed gill, kidney and brain alterations. The degree of tissue change values indicates that increasing vitamin C (VC) levels reduces these alterations. Fish fed diets VC29, VC62 and VC 250 showed a significantly higher growth rate in comparison with those fed the diets VC0, VC7 and VC17 (P > 0.05). The dietary requirement of VC in L. guttatus was estimated to be 29 mg kg^?1 of AA based on weight gain and specific growth rate, but more than 250 mg kg^?1 of AA is required to eliminate clinical signs and histopathological lesions.     

Feeding of tropical trees and shrub foliages as a strategy to reduce ruminal methanogenesis: studies conducted in Cuba

The aim of this paper was to present the main results obtained in Cuba on the effects of feeding tropical trees and shrubs on rumen methanogenesis in animals fed with low quality fibrous diets. More than 20 tree and shrub foliages were screened for phytochemicals and analyzed for chemical constituents. From these samples, seven promising plants (Samanea saman, Albizia lebbeck, Tithonia diversifolia, Leucaena leucocephala, Trichantera gigantea, Sapindus saponaria, and Morus alba) were evaluated for methane reduction using an in vitro rumen fermentation system. Results indicated that the inclusion levels of 25% of Sapindo, Morus, or Trichantera foliages in the foliages/grass mixtures (grass being Pennisetum purpureum) reduced (P < 0.01) methane production in vitro when compared to Pennisetum alone (17.0, 19.1, and 18.0 versus 26.2 mL CH₄/g fermented dry matter, respectively). It was demonstrated that S. saman, A. lebbeck, or T. diversifolia accession 23 foliages when mixed at the rate of 30% in Cynodon nlemfuensis grass produced lower methane compared to the grass alone. Inclusion levels of 15% and 25% of a ruminal activator supplement containing 29% of L. leucocehala foliage meal reduced methane by 37% and 42% when compared to the treatment without supplementation. In vivo experiment with sheep showed that inclusion of 27% of L. leucocephala in the diet increased the DM intake but did not show significant difference in methane production compared to control diet without this foliage. The results of these experiments suggest that the feeding of tropical tree and shrub foliages could be an attractive strategy for reduction of ruminal methanogenesis from animals fed with low-quality forage diets and for improving their productivity.     

Phloem transport of assimilates in relation to flowering time and senescence in barley grown with different availabilities of nitrogen and phosphorus

Understanding the way in which N and P availability affects the transport of sugar and amino acids is crucial to improve grain quality and yield. Thus, in the present study, two greenhouse and field experiments were conducted with barley plants grown with different N and P availabilities to assess the dynamics of the phloem transport of assimilates in relation to the beginning of flowering and senescence. The phloem transport of assimilates decreased before the beginning of protein degradation in all treatments, but the onset of flowering and senescence varied according to the N and P availability, as evidenced by the concentrations of proteins, amino acids, and sugar and the gene expression of senescence-related proteases and all glutamine synthetase isoforms. In N-deficient plants, the phloem transport decreased before flowering, but only when P was not limiting; in N- and P-sufficient plants it decreased at flowering; and in P-deficient plants it decreased after flowering. Therefore, only N-deficient but P-sufficient plants have a post-anthesis period with high export rate of assimilates. This alteration of phenology in relation to phloem leads to important consequences in assimilate utilization, as shown by the higher yield and N content of the former compared to P-deficient plants.     

An integrative study of Sakia sisanganensis n. sp. (Rhabditida: Tylenchidae) from Sisangan forest,Iran, and new morphological observations for the genus

Further data on the morphology (the lip region characters) and phylogeny of the genus Sakia are presented. The new observations were based on scanning electron microscopy (SEM) and light microscopy (LM). A new species, Sakia sisanganensis n. sp., was recovered from rotten wood of a dead beech tree (Fagus orientalis) in northern Iran, herein described and illustrated based on an integrative approach, that is morphological, morphometric and molecular characters. The new species is characterized by a combination of the following features: fine transverse striae and vestigial single band in the lateral field in SEM. Labial area dorso‐ventrally flattened. Oral region with two concentric hexagonal plates, the inner one apparently elevated. Amphidial openings short, slit‐like. Stylet delicate. Median bulb fusiform to spindle‐shaped with weak valvular apparatus. Spermatheca functional. Tail filiform with faintly pointed tip and males common. The new species was morphologically compared with four known species of the genus, viz., S. alii, S. arboris, S. castori and S. indica, all having indistinct lateral fields. Molecular phylogenetic analyses were performed based on the small subunit ribosomal RNA gene (SSU rDNA). In the Bayesian inference (BI), S. sisanganensis n. sp. with two isolates was strongly supported as a sister taxon of a clade harbouring S. arboris + Lelenchus species. However, in the maximum likelihood (ML) analysis, the new species formed a clade with S. arboris, thus supporting the reciprocal monophyly of the genera Sakia and Lelenchus. Accordingly, the test of monophyly was performed (using Bayes factor) and the results did not reject the monophyly of sakia (i.e., S. sisanganensis n. sp. and S. arboris as sister taxa) based on the currently available data.     

An intensive hatchery rearing protocol for larvae of the bullseye puffer,Sphoeroides annulatus (Jenyns)

In this study bullseye puffer, Sphoeroides annulatus larvae were reared from hatching through to 1 or 2 months after weaning on an experimental scale in three replicate 600 L tanks and on three occasions during the spawning season (nine tanks in total). The rearing protocol used was green water (Nannochloropsis oculata and Isochrysis sp.) 100 000 cells mL^?1 from 0 to 11 days after hatch (DAH), 5–10 rotifers, Brachionus rotundiformis mL^?1 from 2 to 26 DAH, 0.1–1 Artemia mL^?1 from 21 to 34 DAH and weaning from 29 to 34 DAH. Survival to a month after weaning was 1%, a total of 3153 juveniles were produced with an average wet weight of 0.29 ± 0.07 g and a length of 27.5 ± 0.82 mm.     

Cotyledon thermal behavior and pectic solubility as related to cooking quality in common beans

The characteristic of proteins, starch and pectic substances in cotyledons of two bean cultivars varying in cooking time were determined to investigate their possible contribution to bean cooking quality. Both cultivars showed the same enthalpies of starch gelatinization but different protein denaturation enthalpies. The proportion of hot water soluble pectins was higher in Michigan, the cultivar with the lower cooking time, than in Ojo de Cabra, the cultivar with the higher cooking time. These results were not due to differences in pectin methylation or in the ratio of monovalent to divalent cations in the tissue, suggesting that in fresh beans the β-elimination reaction is not the sole or predominant route of thermal pectin degradation. Overall, this study indicates that varietal differences in bean cooking quality may be reflections of the rate of pectin loss during soaking/heating and that the thermal properties of starch and protein fractions seem to have a minor contribution. Researchers involved in this study propose that in fresh beans, the thermal pectin loss results from a two step mechanism: pectin enzymic breakdown during the bean soaking followed by thermal solubilization rather than β-elimination during the bean heating.     

A 4-week repeated oral dose toxicity study of dairy fat naturally enriched in vaccenic, rumenic and α-linolenic acids in rats

Few studies have focused on the toxicological risks of dairy fat intake. A standard dairy fat (SDF) with a 70% SFA content and a naturally enriched dairy fat (EDF) in vaccenic, rumenic and α-linolenic acids and low in SFA (54%) have been examined in a 4-week repeated dose oral toxicity study as a daily dose of 2000 mg/kg bw by gavage in rats. Comparisons were established with a third group of rats (control) which did not receive fat administration. Both fats were well tolerated, and no adverse events or mortality were observed during the treatment nor after a 2-week observation period. EDF and SDF did not cause significant differences with respect to a control group in body weight gain, food consumption, clinical observations, organ weight ratios, histopathological findings and most of the hematological and biochemical parameters including total cholesterol and cholesterol fractions in plasma. In rats treated with SDF, a significant increase of triglycerides was observed as compared to the control group. By contrast, in rats treated with EDF, a significant decrease in triglycerides was detected. EDF orally administered to rats was safe, and no treatment-related toxicity was detected. The results also suggest that EDF could protect against the increase of triglyceride concentrations in plasma.     

Pulmonary rhodococcosis in a cat

Feline Rhodococcus equi infection is rare, despite the bacteria is widespread in the environment. R equi infection is typically observed in equine species but the infection has also been reported in dogs, cats and other domestic animals. There are a few reports regarding pulmonary R equi infection in cats and the disease appears to be limited to the skin and the subcutaneous tissue. This report describes the pathological, microbiological and the virulence features associated with an acute necrosuppurative pneumonia in a cat. To the best of our knowledge, this is the first report of feline pulmonary R equi infection in Italy.