Occurrence and incidence of phytoplasmas of the 16SrII-D subgroup on solanaceous and cucurbit crops in Egypt

Symptoms reminiscent of phytoplasma infection were observed in four provinces (governorates) of Egypt in fields of eggplants, tomato plants and squash. Diseased plants exhibited stunting, leaf yellows and flower development abnormalities. PCR amplification of 16SrDNA with phytoplasma-specific primer pairs confirmed the phytoplasma presence. Sequencing and phylogenetic analysis indicated that all phytoplasmas had the same partial 16SrDNA sequence, assigning them to the 16SrII-D phytoplasma subgroup. Disease incidence was about 1% among the 20 squash fields surveyed and equally varied from 4% to 15% in the 20 eggplant fields and in the 40 tomato fields inspected. The widespread distribution of this phytoplasma in annual solanaceous and cucurbit crops suggests a wider plant host range including wild plants that could act as reservoir and insist on the need for a insect vector survey. A finer genetic differentiation of Egyptian 16SrII-D phytoplasma strains from different geographical origins and different host plants should help to better trace such epidemics.     

Dynamics of single mRNPs in nuclei of living cells

Understanding gene expression requires the ability to follow the fate of individual molecules. Here we use a cellular system for monitoring messenger RNA (mRNA)expression to characterize the movement in real time of single mRNA-protein complexes (mRNPs) in the nucleus of living mammalian cells. This mobility was not directed but was governed by simple diffusion. Some mRNPs were partially corralled throughout the nonhomogenous nuclear environment, but no accumulation at subnuclear domains was observed. Following energy deprivation, energy-independent motion of mRNPs was observed in a highly ATP-dependent nuclear environment; movements were constrained to chromatin-poor domains and excluded by newly formed chromatin barriers. This observation resolves a controversy, showing that the energetic requirements of nuclear mRNP trafficking are consistent with a diffusional model.     

Higher water temperature enhances dietary carbohydrate utilization and growth performance in Labeo rohita (Hamilton) fingerlings

A 60-day experiment was conducted to delineate the effect of three dietary levels of gelatinized carbohydrate (GC) on growth, nutrient-utilization and body composition of Labeo rohita fingerlings (avg. wt 6.5 ± 0.3 g) reared at two water temperatures (ambient-AT (26 ± 0.8 °C) and 32 °C). Two hundred and sixteen fingerlings were randomly distributed into six treatments in triplicates. Three semi-purified isonitrogenous diets were prepared with graded levels of GC viz. D(1) : 40%, D(2) : 50% and D(3) : 58%. Growth rate, feed efficiency and protein efficiency ratio were significantly (p < 0.05) higher in 50% GC and 32 °C reared groups than their AT counterparts. Hepato Somatic Index was higher in AT reared groups compared to 32 °C reared counterparts. Apparent digestibility co-efficient of carbohydrate was significantly (p < 0.05) higher at 32 °C reared groups but decreased with increasing carbohydrate (GC) levels. Fish reared at 32 °C showed significantly (p < 0.05) higher amylase, protease and hexokinase activities while glucose-6-phosphate dehydrogenase and glucose-6-phosphatse were significantly (p < 0.05) higher at ambient temperatures. The results obtained in present study indicated that L. rohita could utilize higher level (50%) of dietary carbohydrate at 32 °C.     

Castor beans hulls as a replacement for Tifton 85 hay in lamb diets

The objective of this study was to evaluate the effect of replacing Tifton 85 hay (0, 33, 66, or 100 %) with by castor bean hulls on the intake and nutrient digestibility and performance of 28 noncastrated lambs, averaging 7 months in age, 19.5?±?2.0 kg average live weight, fed on diets based on forage cactus. The animals were housed in individual pens for 100 days. The digestibility trial occurred 40 days after the start of the performance using LIPE® as an external indicator for estimating fecal dry matter production. The replacement of hay with Castor beans hulls linearly decreased the intakes of dry matter, neutral detergent fiber, organic matter, and crude protein and reduced the digestibility coefficients of the dry matter, neutral detergent fiber, organic matter content, crude protein, and total digestible nutrient content. The hot carcass and true carcass yields were not influenced by the treatments and the feed conversion increased linearly. The empty body weight, live weight at slaughter, hot and cold carcass weights, total gain, and average daily gain decreased linearly with the replacement. The replacement of Tifton 85 hay with castor bean hulls reduced the intake of dry matter, crude protein and energy, consequently reducing the performance of the animals. However, as the regression coefficients were of low magnitude, data were subjected to analysis of variance and means were compared using the Dunnett test with diet without castor bean hulls set as the control treatment. The Tifton 85 hay can be replaced up to 66 % by castor bean hulls in finishing diets for lambs.