Functional linseed fibres and their impacts on silver catfish (Rhamdia quelen) nutrition

This study was conducted with the objective of evaluating the combination of different ratios of soluble and insoluble linseed fibre for silver catfish (Rhamdia quelen). For this, the soluble and insoluble fractions were concentrated separately and combined in four ratios (1:0.5, 1:1, 1:2, 1:4), which were added to silver catfish diets and evaluated in a bioassay. After 45 days of receiving the experimental diets, the animals were submitted to biometry to collect data and tissues. The experimental design was completely randomized, with five treatments and four replications and the means were compared by Tukey's test (p < .05). Diets 1:2 and 1:4 provided higher weight gain, specific growth rate and crude protein deposition to the fish, whereas only the 1:4 diet reflected higher crude body protein. The 1:0.5 diet altered the trypsin activity in the intestine, and, together with the 1:4 diet, it provided a higher intestinal villi height. Body yield, somatic and digestive parameters, chymotrypsin activity and glucose, glycogen and liver protein were not altered, regardless of the experimental diets. In conclusion, the results indicate that linseed fibre acts effectively as a growth promoter in silver catfish diets, with the use of 1:2 and 1:4 ratios optimizing its prebiotic action.     

Mortality of the short-neck clam <Emphasis Type="Italic">Ruditapes philippinarum</Emphasis> induced by the toxic dinoflagellate <Emphasis Type="Italic">Heterocapsa circularisquama</Emphasis>

Mortality of the short-neck clam Ruditapes philippinarum exposed to the toxic dinoflagellate Heterocapsa circularisquama was studied under controlled conditions to clarify the mechanisms of recurrent mass deaths of clams occurring in western Japanese coastal areas. One-week mortality tests, involving three water temperatures, six H. circularisquama concentrations, and two clam body sizes, showed a significant increase in mortality with increasing temperature, H. circularisquama concentration, exposure duration, and body size (ANOVA, P < 0.01). Clam death was observed at concentrations as low as 50 cells/ml and temperatures as low as 15°C. Prior to death, clams showed an extreme retraction of their mantle edge and siphon, along with recurrent vomiting behavior before initiating a closure reaction followed by paralysis then death. Gills of paralyzed clams showed an important uptake of dye, implying gill damage. This study is the first laboratory evidence of bivalve mortality induced by H. circularisquama at low concentrations and low temperature, and the first report of differential effects according to the body size of bivalves.     

The role of vascular bundles on the mechanical properties of coconut palm wood

This study examines certain physical, mechanical, and anatomical characteristics of coconut palm wood. The results show a correlation between the anatomical characteristics and density as well as lengthwise compression. All properties (density, frequency of vascular bundles (VBs), and mechanical properties) increase with the transverse distance from the center of the trunk. The study also tests VBs from different radial sections of the coconut palm tree (Cocos nucifera) for diameter, ultimate tensile strength, and modulus of elasticity. The influence of the VBs on the overall properties of the wood is discussed.     

Microcephalin, a gene regulating brain size, continues to evolve adaptively in humans

The gene Microcephalin (MCPH1) regulates brain size and has evolved under strong positive selection in the human evolutionary lineage. We show that one genetic variant of Microcephalin in modern humans, which arose approximately 37,000 years ago, increased in frequency too rapidly to be compatible with neutral drift. This indicates that it has spread under strong positive selection, although the exact nature of the selection is unknown. The finding that an important brain gene has continued to evolve adaptively in anatomically modern humans suggests the ongoing evolutionary plasticity of the human brain. It also makes Microcephalin an attractive candidate locus for studying the genetics of human variation in brain-related phenotypes.     

Effects of different concentrations of Chir98014 as an activator of Wnt/beta-catenin signaling pathway on oocyte in-vitro maturation and subsequent embryonic development in Sanjabi ewes

The present study was conducted to investigate the effects of the activator factor of the WNT pathway, chir98014, leading to the in vitro sheep oocyte maturation medium, on the cumulus cell development, different nuclear maturation stages and the following process of embryonic development. Experiments included (a) addition of different concentrations (0, 0.1, 0.5, 1 µm) of chir98014 to the maturation medium and evaluation of the cumulus cell expansion, (b) addition of different concentrations of chir98014 to the maturation medium and investigation of different nuclear maturation stages, (c) addition of different concentrations of chir98014 to the maturation medium and examination of the subsequent embryonic maturation process and (d) addition of different concentrations of chir98014 to the embryonic development culture medium (the first 48 hr) and investigation of the subsequent embryonic development process. The extracted data were analysed using the SPSS software, considering the significance level of p < .05 and making the mean comparisons. The results showed that the addition of the 0.1 µM concentration of chir98014 to the maturation medium had no significant effects on the oocyte maturation and embryo development post-fertilization but it enhanced the Cumulus-oocyte complexes (COCs) expansion. In the fourth experiment, the low concentration of chir98014 in the embryo culture media improved the embryo development process, whereas the high one had a detrimental effect on it, as compared to the control group. Thus, the presence of the lower concentrations of this compound in the embryonic culture medium had favourable effects on the development of embryos.     

Performance,meat characteristics and economic viability of rabbits fed diets containing banana peel

Tropical Animal Health and Production - In developing countries, agricultural areas are used to grow ingredients for rabbits’ nutrition instead of food for the human population. In this...     

Remediation of metal-contaminated mine tailings by the application of organic and mineral amendments

Journal of Soils and Sediments - Tailings are generally characterized by severe physicochemical conditions that limit the establishment of vegetation. The present study aimed to select suitable...     

Effects of plant density and mepiquat chloride application on cotton boll setting in wheat–cotton double cropping system

Sowing cotton directly after harvesting wheat in the Yangtze River Valley of China requires early mature of cotton without yield reduction. Boll-setting period synchronisation and more yield bolls distributed at the upper and middle canopy layers are also required for harvesting. The objective of this study is to quantify the individual and interaction effects of plant density and plant growth regulator mepiquat chloride(MC) on temporal and spatial distributions of yield bolls, as well as yield and yield components. During the 2013–2016 cotton growing seasons, the experiments were conducted on a shortseason cotton cultivar CRRI50 at Yangzhou University, China. Various combinations of plant density(12.0, 13.5 and 15.0 plants m~(–2)) and MC dose(180, 270 and 360 g ha~(–1)) were applied on cotton plants. The combination of 13.5 plants m~(–2) and 270 g ha~(–1) MC resulted in the greatest boll number per unit area, the highest daily boll setting number and more than 90% of bolls positioned within 45–80 cm above the ground. In conclusion, appropriate MC dose in combination of high plant density could synchronize boll-setting period and retain more bolls at the upper and middle canopy layers without yield reduction in the system of direct-seeded cotton after wheat harvest, and thus overcome the labor-intensive problem in current transplanting cropping system.     

Reduced square Bacillus thuringiensis insecticidal protein content of transgenic cotton under N deficit

To clarify the effect of the N deficit on the amount of square Bt insecticidal protein, different N application rates(0, 75, 150, 225, and 300 kg ha–1) were imposed on the conventional cultivar Sikang 1(SK-1) and hybrid cultivar Sikang 3(SK-3) during 2015–2016 cotton growth seasons. Under different N application rates, the square number per plant, square volume and square dry weight reduced when the N rates decreased from conventional rate(300 kg ha–1) to 0 kg ha–1. And the square Bt protein content decreased accordingly. The analysis of N metabolism showed that soluble protein content, GPT and GOT activities decreased, free amino acid, peptidase and protease activities increased under N deficit. Correlation analysis indicated that the reduced Bt protein content under N deficit was related to altered N metabolism. In conclusion, square development and the amount of square Bt toxin both decreased under N deficit, indicating that promoting the square development under appropriate N application rate would also promote the insect resistance during squaring stage.