Efficacy of Organic Soil Amendments for Management of Heterodera glycines in Greenhouse Experiments

In a repeated greenhouse experiment, organic soil amendments were screened for effects on population density of soybean cyst nematode (SCN), Heterodera glycines, and soybean growth. Ten amendments at various rates were tested: fresh plant material of field pennycress, marigold, spring camelina, and Cuphea; condensed distiller’s solubles (CDS), ash of combusted CDS, ash of combusted turkey manure (TMA), marigold powder, canola meal, and pennycress seed powder. Soybeans were grown for 70 d in field soil with amendments and SCN eggs incorporated at planting. At 40 d after planting (DAP), many amendments reduced SCN egg population density, but some also reduced plant height. Cuphea plant at application rate of 2.9% (amendment:soil, w:w, same below), marigold plant at 2.9%, pennycress seed powder at 0.5%, canola meal at 1%, and CDS at 4.3% were effective against SCN with population reductions of 35.2%, 46.6%, 46.7%, 73.2%, and 73.3% compared with control, respectively. For Experiment 1 at 70 DAP, canola meal at 1% and pennycress seed powder at 0.5% reduced SCN population density 70% and 54%, respectively. CDS at 4.3%, ash of CDS at 0.2%, and TMA at 1% increased dry plant mass whereas CDS at 4.3% and pennycress seed powder at 0.1% reduced plant height. For Experiment 2 at 70 DAP, amendments did not affect SCN population nor plant growth. In summary, some amendments were effective for SCN management, but phytoxicity was a concern.     

Comparative study of freezing time and temperature for effective Plodia interpunctella control using typical storage containers

Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae) is a moth species that is able to feed on various vegetable commodities. Its control is economically critical for commercial food storing facilities such as warehouses. P. interpunctella causes quantitative and qualitative damage by eating important stored food crops such as dried Welsh onions (Allium fistulosum L.), and freezing treatment is a common method of control. To examine the effectiveness of freezing treatment, we changed the length of time of the conventional freezing method. The conventional method involves treatment below ?15 °C for 48 h, but we predicted that it would be effective with only 24 h freezing at ?25 °C. To test our theory, we conducted an experiment using three different frozen storage containers and assessed if the modified method was effective on the eggs and fourth instar larvae of P. interpunctella. Despite the temporary malfunctioning of one of the containers used in the experiment after incubation at 28 °C and 70% relative humidity for 10 days, the larval mortality rate was 100% and egg hatching rate was 0% in all samples, regardless of the treatment time. Further research is needed as this method is expected to decrease production costs and energy consumption and has the potential to be applied to other crops and pests.     

Comparative analysis of the ileal bacterial composition of post-weaned pigs fed different high-quality protein sources

To further understand the contribution of feedstuff ingredients to gut health in swine, gut histology and intestinal bacterial profiles associated with the use of two high-quality protein sources, microbially enhanced soybean meal (MSBM) and Menhaden fishmeal (FM) were assessed. Weaned pigs were fed one of three experimental diets: (1) basic diet containing corn and soybean meal (Negative Control (NEG)), (2) basic diet + fishmeal (FM; Positive Control (POS)) and (3) basic diet + MSBM (MSBM). Phase I POS and MSBM diets (d 0 to d 7 post-wean) included FM or MSBM at 7.5%, while Phase II POS and MSBM diets (d 8 to d 21) included FM or MSBM at 5.0%. Gastrointestinal tissue and ileal digesta were collected from euthanised pigs at d 21 (eight pigs/diet) to assess gut histology and intestinal bacterial profiles, respectively. Data were analysed using Proc Mixed in SAS, with pig as the experimental unit and pig (treatment) as the random effect. Histological and immunohistochemical analyses of stomach and small intestinal tissue using haematoxylin–eosin, Periodic Acid Schiff/Alcian blue and inflammatory cell staining did not reveal detectable differences in host response to dietary treatment. Ileal bacterial composition profiles were obtained from next-generation sequencing of PCR generated amplicons targeting the V1 to V3 regions of the 16S rRNA gene. Lactobacillus-affiliated sequences were found to be the most highly represented across treatments, with an average relative abundance of 64.0%, 59.9% and 41.80% in samples from pigs fed the NEG, POS and MSBM diets, respectively. Accordingly, the three most abundant Operational Taxonomic Units (OTUs) were affiliated to Lactobacillus, showing a distinct abundance pattern relative to dietary treatment. One OTU (SD_Ssd_00001), most closely related to Lactobacillus amylovorus, was found to be more abundant in NEG and POS samples compared to MSBM (23.5% and 35.0% v. 9.2%). Another OTU (SD_Ssd_00002), closely related to Lactobacillus johnsonii, was more highly represented in POS and MSBM samples compared to NEG (14.0% and 15.8% v. 0.1%). Finally, OTU Sd_Ssd-00011, highest sequence identity to Lactobacillus delbrueckii, was found in highest abundance in ileal samples from MSBM-fed pigs (1.9% and 3.3% v. 11.3, in POS, NEG and MSBM, respectively). There was no effect of protein source on bacterial taxa to the genus level or diversity based on principal component analysis. Dietary protein source may provide opportunity to enhance presence of specific members of Lactobacillus genus that are associated with immune-modulating properties without altering overall intestinal bacterial diversity.     

水华蓝藻对鱼类的营养毒理学效应

水体富营养化导致蓝藻水华的发生已成为全球关注的水环境问题,很多鱼类处于水生态系统食物链的最高级,蓝藻水华的主要次级代谢产物-微囊藻毒素可通过鱼类的摄食活动或生物富集作用在鱼体组织中累积,并通过食物链危及人类健康。近年来,微囊藻毒素对鱼类的毒性效应引起众多科学家的关注。在天然水体中不少鱼类可以主动摄食蓝藻,所以,水华蓝藻对鱼类来说既具有营养物作用、也具有潜在的毒性作用。鉴于目前机械收获的水华蓝藻生物量资源化利用问题以及水产饲料业亟需大力开发鱼粉替代蛋白源的需要,从营养学和毒理学这两个角度来研究水华蓝藻对鱼类的营养作用和毒性效应具有较高的理论和现实意义。主要概述了蓝藻粉、蓝藻细胞对鱼类的营养学和毒理学效应,以期拓展水华蓝藻对鱼类毒性效应的研究视野,同时也为水华蓝藻的资源化利用提供新的思路。     

Encapsulation of soybean meal with fats enriched in palmitic and stearic acids: effects on rumen-undegraded protein and in vitro intestinal digestibility

Fat coating of soybean meal (SBM) can reduce its protein degradability in the rumen, but the encapsulation of SBM with palmitic (PA) and stearic acids (SA) has not yet been investigated, despite both fatty acids are common energy sources in dairy cow diets. This study aimed to evaluate the effects of applying a novel method, using either 400 or 500 g fat/kg (treatments FL40 and FL50, respectively), which was enriched in PA and SA at different ratios (100:0, 75:25, 50:50, 25:75 and 0:100), on physical and chemical characteristics, ruminal degradability, solubility and in vitro intestinal protein digestibility (IVIPD) of the obtained products. Encapsulation of SBM in fat resulted in greater mean particle size and lower bulk density and protein solubility than unprotected SBM (USBM). Treatment FL50 resulted in increased (p < 0.01) rumen-undegraded protein (RUP) compared to USBM. There were no differences in RUP of SBM when different PA: SA ratios were used. The mean RUP content of treatments FL40 and FL50 (306 and 349 g/kg, respectively) was greater compared to USBM (262 g/kg, p < 0.05), but lower than that for a standard heat-treated SBM (431 g/kg). Values of IVIPD did not differ among SBM, heat-treated SBM and FL40 and FL50 samples, all being greater than 97.8%. In conclusion, encapsulation of SBM with fats enriched in PA and SA proved to be effective in reducing protein solubility and increasing RUP without depressing protein digestibility in the intestine. For validation of the method, in vivo research to investigate the effects of these products on the production of dairy cows is warranted.     

Late isocaloric eating increases hunger,decreases energy expenditure,and modifies metabolic pathways in adults with overweight and obesity

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Compensatory feeding in response to variable food quality by Melanoplus differentialis

Abstract. The behavioural mechanisms driving compensatory food consumption in response to dietary dilution as well as the relationship between feeding time and food residence time (i.e. digesta retention time in the gut) were studied using the non-diapausing strain of the grasshopper Melanoplus differentialis (Thomas) (Orthoptera: Acrididae). 3-day-old, sixth-instar nymphs and 3-day-old adults were fed artificial diets containing 1%, 3% and 5% total nitrogen (N) at 30C, LD 14:10h; the feeding behaviour was recorded using electronic monitoring devices connected to microcomputers for 24 h. The percentage of time spent feeding increased linearly as diets were diluted using non-digestible cellulose from 5% to 1% N. This response was due to an increase in the number of meals while the meal duration of a feeding bout was unaltered. Sixth-instar nymphs spent about 40% more time feeding than the larger adults. The increased feeding time in nymphs resulted from both more frequent feeding bouts and longer meal duration. Feeding time and food residence time were highly negatively related.     

Conditions of Phenol Extraction of RNA from Rat Liver Subcellular Cytoplasmic Fractions I. Effect of a Precipitation of Microsomal RNA on its Purity

Purification of RNA extracted with phenol from rat liver microsomes by precipitation in sodium benzoate and phenol solutions resulted in the removal of a readily measurable amount of proteins and polysaccharides. The stabilization of RNA was observed by changes in the profiles of the centrifugation gradients. This effect was the same over a wide range of yields in RNA obtained with extraction in the presence of buffers with varying pH levels.     

Volume of Protein meals taken by females of the blowfly, Lucilia cuprina: ovarian development-related and direct effects of protein ingestion

Abstract. The effect of the stage of ovarian development on the volumes of meals of the protein-rich material, liver exudate, taken by females of the blowfly, L. cuprina (Wiedemann), was examined using an experimental regime which was designed to isolate the effects of ovarian development from any other more direct effects of protein feeding or deprivation. It was found that volumes of meals taken by females with developing ovaries were little, if any, smaller than the volumes taken by protein-deprived females until quite late in vitellogenesis, at which stage meal size fell abruptly to that of meals taken by gravid females. A direct effect of protein-feeding was also demonstrated, with females that had consumed exudate during the previous few hours taking substantially smaller meals than those that had not done so. This effect was, however, shown to be non-specific in that the recent consumption of an equal volume of concentrated sucrose solution caused a similar reduction in the volume of exudate taken.