Effects of dietary supplementation of a purified nucleotide mixture on immune function and disease and stress resistance in channel catfish,Ictalurus punctatus

Juvenile channel catfish (14.4 g average initial weight) were fed diets supplemented with a purified nucleotide mixture for 8 weeks. The mixture consisted of five nucleotides supplied on an equal basis as disodium salts at combined concentrations of 0 (control), 0.1%, 0.3%, 0.9% or 2.7% of diet. Addition of nucleotides to diet produced a dose‐dependent reduction in survival of channel catfish to Edwardsiella ictaluri. Although the reasons are unclear, the high levels of nucleotides supplemented in this study may have contributed to the decrease in disease resistance, and this decrease appeared to be unrelated to the innate immune (unaffected) and specific antibody (enhanced) responses. Stress resistance increased with a corresponding amelioration of the immunosuppressive effects of the stress response on non‐specific immunity (lysozyme and bactericidal activity) as nucleotides increased in diet. Use of exogenous nucleotides as a prophylactic treatment before culture‐related stress exposure may prove beneficial by decreasing the immunosuppressive effects of stress but not in prevention of ESC.     

Effects of prolonged fasting on levels of metabolites,oxidative stress,immune-related gene expression,histopathology, and DNA damage in the liver and muscle tissues of rainbow trout (Oncorhynchus mykiss)

Fish Physiology and Biochemistry - This study was conducted to assess the impacts of prolonged fasting (70 and 120 days) on the morphological, biochemical, oxidative stress responses,...     

Ameliorative effects of biological treatments on growth of squash plants under salt stress

The objective of this work was to evaluate the effect of selected biologicals on direct seeded and transplanted squash plant growth and mineral content under salinity stress. The study was conducted in pot experiments using a mixture of sandy loam soil:vermiculite (1:1, v:v) under controlled greenhouse conditions. Biologicals tested included AgBlend, SoilBuilder, Yield Shield, PlantShield, Inoculaid and Equity. Salinity treatments were established by adding 0, 50 and 100 mM of NaCl to a base complete nutrient solution (Hydro-Sol + Ca(NO₃)₂). Pots were irrigated with NaCl solutions and biological treatments were included in the water. Yield Shield was applied as a seed treatment. Salinity negatively affected growth of squash; however, biological treatments significantly increased fresh weight compared to non-treated plants that were challenged with salt stress. Furthermore, biological treatments tested increased the uptake of potassium compared to the non-treated control in both direct seeded and transplanted squash. Sodium concentration was not affected by biologicals in directed seeded squash except for SoilBuilder, Yield Shield and Equity at 100 mM, while AgBlend, SoilBuilder, Inoculaid and Equity decreased sodium uptake in transplants under salt stress. The most effective biologicals increased the K⁺/Na⁺ ratio, which was positively correlated with plant growth. Alteration of mineral uptake may be one mechanism for the alleviation of salt stress. Based on the results of the experiment reported herein, the use of biological treatments may provide a means of facilitating plant growth under salt stress.     

First report of dry rot of potato caused by Fusarium sambucinum in Kyrgyzstan

Journal of Plant Diseases and Protection - In October 2020, the presence of an intense Fusarium dry rot disease was detected during a survey of potato tubers in the production storage facilities in...     

Oil-Water Interface Templating of Mesoporous Macroscale Structures

Ordered mesostructured porous silicas that are also macroscopically structured were created by control of the interface on two different length scales simultaneously. Micellar arrays controlled the nanometer-scale assembly, and at the static boundary between an aqueous phase and an organic phase, control was achieved on the micrometer to centimeter scale. Acid-prepared mesostructures of silica were made with the p6, Pm3n, and the P63/mmc structures in the form of porous fibers 50 to 1000 micrometers in length, hollow spheres with diameters of 1 to 100 micrometers, and thin sheets up to 10 centimeters in diameter and about 10 to 500 micrometers in thickness. These results might have implications for technical applications, such as slow drug-release systems or membranes, and in biomineralization, where many processes are also interface-controlled.     

Identification and characterization of Streptococcus agalactiae isolated from horses.

Seven group B streptococcal cultures isolated from three horses reacted with group B-specific antiserum, were CAMP positive, pigmented and showed the typical biochemical properties of Streptococcus agalactiae. The identification could be confirmed by PCR amplification of the 16S rRNA gene and a subsequent RsaI restriction pattern typical for S. agalactiae. In addition, the isolates were identified by amplification of species specific parts of the 16S rRNA gene, the 16S-23S rRNA intergenic spacer region and by amplification of the CAMP-factor (cfb) gene. Six isolates could be classified as serotype III/Rib, one isolate as serotype Ia/cbeta. The occurrence of the protein antigens Rib and cbeta could be confirmed by PCR amplification of the respective genes. The six isolates of serotype III/Rib were hyaluronidase negative, had a hylB gene with a size of 4.6 kb and an insertion element IS1548 of 0.98 kb. The isolate of serotype Ia/cbeta was hyaluronidase positive, had a hylB gene with a size of 3.3 kb and no insertion element IS1548. In addition, all seven isolates had the insertion element ISSag2 and the gene lmb encoding the laminin binding surface protein Lmb and the gene scpB encoding C5a peptidase. According to the present results the group B streptococci isolated from horses showed characteristics of human isolates of this species.     

Screening of barley landraces by direct selection for crop improvement

Abstract

Barley (Hordeum vulgare L.) landraces display a high degree of variability in morphological and developmental traits, in disease resistance, and in protein content. Representatives of 29 barley landraces from southeast Turkey were collected from farmers’ fields, for a total of 800 accessions. The objectives of this study were to characterize these accessions over four years for morphological and agronomical traits to be used for future selection and breeding program. The observed variation between landraces was very large for all traits. In the first year of testing the accessions showed average grain yields ranging from 197–2225 kg ha^?1. After three years of selection, promising accessions were tested at two different geographical regions and using two different irrigation methods. One line was identified which significantly out-yielded the local landrace in all of the testing years and had a higher average yield than the check genotypes.     

Optimal dose and timing in phytohaemagglutinin skin-testing of deer

AIM: To establish the optimal dose of the mitogen phytohaem- agglutinin (PHA) and the optimal time for measuring increased skin-fold thickness in red deer following intradermal injection, as an indicator of cell-mediated immune response.

METHODS: Three doses (10, 50 and 250 µg) of PHA were injected intradermally in the right side of the neck, and phosphate buffered saline (PBS) was injected at a fourth site as a control, in 20 captive Iberian red deer (Cervus elaphus hispanicus) hinds. Skin-fold thicknesses were measured at 0, 12, 24, 36, 48, 60, 72, 84 and 96 h following injection.

RESULTS: The highest dose of PHA tested (250 µg) resulted in a clear and long-lasting cellular response; increases in skin-fold thickness between 48 and 84 h post-injection varied minimally and response correlated positively with liveweight. No correlations with liveweight and no clear increases in skin-fold thickness occurred at the lower doses of PHA or the PBS.

CONCLUSIONS AND CLINICAL RELEVANCE: This technique could be applied with minimal training and without specialised equipment in deer, for immunological and ecological research.