Larval rearing of fringe-lipped carp,Labeo fimbriatus (Bloch) with low cost diets including green bottle fly Lucilia sericata (Meigen) larvae meal incorporated diet

A study was conducted with non-conventional ingredients to test their efficacy as fishmeal (FM) replacers in the diet of fringe- lipped carp. Labeo fimbriatus first feeding larvae and fry were reared for 30 and 60 days in indoor, 50 L, aerated, circular plastic tanks at 100 and 30 numbers tank⁻¹, respectively. In the first feeding larvae to fry rearing experiment (Exp. 1), the fish were fed with either of the following isonitrogenous and isocaloric diets – live plankton, FM diet, green bottle fly (Lucilia sericata) larvae meal (GBFLM) diet and silkworm pupa (SWP) diet. The fry to fingerling rearing (Exp. 2), was also conducted using the same diets described above except live plankton. All compounded diets were formulated to contain 40% crude protein for the experiment 1 and 35% for experiment 2 and were fed ad libitum. Triplicate tanks were maintained for each treatment in both the experiments. In Exp. 1, the mean final weight of fry was higher with plankton and FM diets, while no difference (p > .05) was observed between FM and GBFLM diets. Weight of fish fed SWP diets was not statistically different from those fed GBFLM diet. No difference (p > .05) in final length, survival and condition factor was recorded. Analysis of digestive enzyme activity of whole fish revealed lower (p < .05) activity of amylase in fish fed plankton. In Exp. 2, no difference (p > .05) was observed between the different diet groups in terms of mean final weight, length, survival and condition factor. Analysis of digestive enzyme activity of whole fish revealed no difference (p > .05) in the activity of digestive enzymes between the treatments except a lower (p < .05) activity of trypsin in FM diet and lipase in FM and GBFLM diets. Since the survival and condition factors of animals is the most important aspect during nursery rearing, similar (p > .05) values recorded in different treatments indicate the possibility of incorporation of these non-conventional protein sources in the diet of L. fimbriatus during first feeding larvae to fry and fry to fingerling rearing.     

Purification and characterization of a novel β-glucosidase from Aspergillus flavus and its application in saccharification of soybean meal

Abstract

Aspergillus flavus has been regarded as a potential candidate for its production of industrial enzymes, but the details of β-glucosidase from this strain is very limited. In herein, we first reported a novel β-glucosidase (AfBglA) with the molecular mass of 94.2?kDa from A. flavus. AfBglA was optimally active at pH 4.5 and 60?°C and is stable between pH 3.5 and 9.0 and at a temperature of up to 55?°C for 30?min remaining more than 90% of its initial activity. It showed an excellent tolerance to Trypsin, Pepsin, Compound Protease, and Flavourzyme and its activity was not inhibited by specific certain cations. AfBglA displayed broad substrate specificity, it acted on all tested pNP-glycosides and barley glucan, indicating this novel β-glucosidase exhibited a β-1, 3-1, 4-glucanase activity. Moreover, the AfBglA could effectively hydrolyze the soybean meal suspension into glucose and exhibit a strong tolerance to the inhibition of glucose at a concentration of 20.0?g/L during the saccharification. The maximum amount of the glucose obtained by AfBglA corresponded to 67.0?g/kg soybean meal. All of these properties mentioned above indicated that the AfBglA possibly attractive for food and feed industry and saccharification of cellulolytic materials.     

Comparison of insecticidal paint and deltamethrin against Triatoma infestans (Hemiptera: Reduviidae) feeding and mortality in simulated natural conditions

The vector of Chagas disease, Triatoma infestans, is largely controlled by the household application of pyrethroid insecticides. Because effective, large‐scale insecticide application is costly and necessitates numerous trained personnel, alternative control techniques are badly needed. We compared the residual effect of organophosphate‐based insecticidal paint (Inesfly 5A IGR? (I5A)) to standard deltamethrin, and a negative control, against T. infestans in a simulated natural environment. We evaluated mortality, knockdown, and ability to take a blood meal among 5^th instar nymphs. I5A paint caused significantly greater mortality at time points up to nine months compared to deltamethrin (Fisher's Exact Test, p < 0.01 in all instances). A year following application, mortality among nymphs in the I5A was similar to those in the deltamethrin (χ2 = 0.76, df=1, p < 0.76). At months 0 and 1 after application, fewer nymphs exposed to deltamethrin took a blood meal compared to insects exposed to paint (Fisher's Exact Tests, p < 0.01 and p < 0.01, respectively). Insecticidal paint may provide an easily‐applied means of protection against vectors of Chagas disease.     

Development of Dactylaria eudermata Drechsler a predaceous fungi in Meloidogyne incognita

Dactylaria eudermata Drechsler is one of the important predaceous fungi occurring widely in different soils. The fungus produces hyphal bails and network compound in which nematodes are entangled. This hyphal nets as trapping structure which may be single dimensional to two or three dimensional and are formed through repeated hyphal anastomosis, which capture nematodes either through the adhesive material present on the surface of hyphal nets or due to physical entanglement. In the experiment it was observed that inflation of hyphal bails takes 30 to 50 minutes and capturing and killing the nematode by a single conidia in water takes 35–55 hours, were as time required for inflation of hyphal bails and real trapping and killing of a nematode in maize meal (MMA: water (1:10) medium) takes one minute and 30–50 hours respectively.     

Combination of meal and exercise timing with a high-fat diet influences energy expenditure and obesity in mice

In mice, obesity has been observed not only in those freely fed a high-fat diet (HFD) but also in those fed while physically inactive. In contrast, a HFD during physically active periods protects against obesity and the impairments in the circadian rhythm induced by free feeding of a HFD. Although exercise is known to be effective for obesity prevention and management, the optimal timing of exercise has not yet been determined. In the present experiments, we aimed to determine the best combination of daily timing of HFD consumption and exercise for the prevention of HFD-induced weight gain in mice. In this experiment, “morning” refers to the beginning of the active phase (the “morning” for nocturnal animals). Increases in body weight related to free feeding of a HFD was significantly reduced with 4?h of exercise during the late (evening) or middle (noon) active period compared to 4?h of exercise during the early (morning) active period or free access to exercise, which resulted in hours of exercise similar to that of morning exercise. These results suggested that eating in the morning or at noon followed by exercise in the evening could prevent weight gain more effectively than exercise in the morning followed by eating at noon or in the evening. The group fed a HFD for 4?h in the morning had lower body weight than the group fed a HFD for 4?h in the evening without exercise. The last group of experiments tested the hypothesis that there would be an interaction between mealtime and exercise time (i.e. time of day) versus order (i.e. which comes first) effects. We compared groups that exercised for 4?h at noon and were fed either in the morning or evening and groups that were fed for 4?h at noon and either exercised in the morning or evening. We found that the groups that were fed before exercise gained less body and fat weight and more skeletal muscle weight compared to the groups that exercised before eating. Corresponding to the body and fat weight changes, the respiratory exchange ratio (RER) was lower and energy expenditure was higher in the groups fed before exercise than in the groups fed after exercise, and these effects on energy metabolism were also observed in the early stage of HFD feeding before obesity. When obese mice fed a HFD for 12 weeks were exposed to a combination of feeding and exercise timing in an effort to reduce body weight, eating followed by exercise resulted in greater weight loss, similar to the experiments conducted to prevent weight gain. These results demonstrate that a combination of daily timing of eating and exercise may influence weight gain and that eating followed by exercise may be effective for minimizing increases in body and fat weight as well as maximizing increases in skeletal muscle weight.     

不依赖连接反应的高通量克隆方法

以脱脂菜籽粕酶解的复合氨基酸为主要原料,螯合率为考察指标,采用L16(4 5)正交试验设计,考察了pH值、温度、时间和配位比对螯合率的影响.结果显示,影响因素的高低顺序为:配位比＞pH值＞时间＞温度.结果表明,复合氨基酸与铜螯合的主要影响因素为pH值和配位比,且配位比的影响达到极显著水平.最佳工艺条件为:时间50 min,温度50℃,配位比2∶1,pH为9,此条件下的复合氨基酸螯合铜的螯合率为94.59％,氨基酸含量为30.2％.     

Nutritional assessment and fate of dna of soybean meal from roundup ready or conventional soybeans using rats

This study was conducted to compare the safety of soybean meal prepared from genetically modified (GM) glyphosate-tolerant (Roundup Ready; RR) soybeans and conventional soybeans. Eighty Sprague-Dawley rats (40 males and 40 females) were randomly allotted to one of four groups according to sex and body weight for a 13-week feeding experiment. The rats were fed corn-based diets containing 60% conventional soybean meal, a mixture of 30% conventional and 30% RR soybean meal, 60% or 90% RR soybean meal. All diets were adjusted to an identical nutrient level except the 90% RR diet. The two soybean meals were similar in chemical analysis and amino acid composition. During the 13-week growth trial, body weight (P?P?meal at the first week. No treatment-related deaths occurred during the experiment. Gross necropsy findings, haematological or urinalysis values and clinical serum parameters showed no meaningful differences between rats fed the control and RR soybean meals. A 145?bp of cp4 epsps gene specific for the GM constructs from RR soybean meal or a 407?bp of lec gene from endogenous soybean DNA could not be detected in investigated masseter muscle samples. No adverse effects of glyphosate-tolerant soybean meal on rats were seen even at levels as high as 90% of the diet.     

鸡肉粉完全替代鱼粉饲料中补充包被氨基酸对凡纳滨对虾生长、体成分及组织氨基酸含量的影响

为了探讨鸡肉粉完全替代鱼粉时饲料氨基酸的平衡性以及外源氨基酸的添加方式与凡纳滨对虾生长、体成分、血浆游离氨基酸及肌肉氨基酸含量的关系, 本试验采用26因子试验设计进行了为期56d的饲养试验。2个饲料蛋白质水平分别为40%和32%, 6个饲料处理分别为鱼粉组(对照组)、鸡肉粉组、鸡肉粉+晶体EAA组、鸡肉粉+晶体EAA+晶体NEAA组、鸡肉粉+包被EAA组、鸡肉粉+包被EAA+包被NEAA组, 配制12组饲料。将凡纳滨对虾(0.300.01) g随机分配到36个圆桶(150 L)中, 每桶30尾, 每3个桶为一个处理组, 饲喂一种饲料, 每天饱食投喂三次。在每一饲料蛋白质水平下, 无论是补充晶体氨基酸(CAA)组还是包被氨基酸组对虾的增重率均显著高于鸡肉粉组(P0.05), 且在32%蛋白质水平下, 包被EAA组对虾增重率达到了鱼粉组水平(P0.05); 补充晶体EAA+NEAA组对虾增重率与补充晶体EAA组无差异(P0.05), 但均显著低于补充包被氨基酸组(P0.05); 补充包被EAA组对虾增重率显著高于补充包被EAA+NEAA组(P0.05)。饲料系数的变化正好与增重率变化相反(P0.05)。饲喂高蛋白质水平饲料较之饲喂低蛋白质饲料明显提高对虾增重率、虾体蛋白含量(P0.05), 但降低虾体脂肪含量(P0.05)。包被氨基酸组凡纳滨对虾血浆游离氨基酸含量总体显著低于CAA组(P0.05)。除谷氨酸、甘氨酸以及脯氨酸外, 各组对虾肌肉氨基酸含量无显著差异(P0.05)。结果表明, 在32%饲料蛋白质水平下, 用鸡肉粉完全替代鱼粉时, 饲料中补充包被EAA可明显促进凡纳滨对虾的生长, 且达到了鱼粉组的饲喂效果。     

The use of a tannin crude extract from Cistus ladanifer L. to protect soya-bean protein from degradation in the rumen

Cistus ladanifer L. (CL) is a perennial shrub abundant in dry woods and dry land of Mediterranean zone, with high level of tannins. Tannins bind to protein, preventing its degradation in the digestive compartments. This tannin/protein complex may be advantageous when partially protecting good-quality feed protein from excessive rumen protein degradation. The objective of this trial was to use a CL phenol crude extract to prevent excessive rumen degradation of soya-bean meal protein. The phenolic compounds were extracted using an acetone/water solution (70:30, v/v). Soya-bean meal was then treated with this crude CL extract, containing 640 g of total phenols (TP) per kg of dry matter (DM), in order to obtain mixtures with 0, 12.5, 25, 50, 100 and 150 g of TP per kg DM. Three rumen-cannulated rams were used to assess in sacco rumen degradability of DM and nitrogen (N). The three-step in vitro procedure was used to determine intestinal digestibility. Increasing extract concentrations quadratically decreased the N-soluble fraction a (R² = 0.96, P = 0.0001) and increased the non-soluble degradable fraction b (R² = 0.92, P = 0.005). The rate of degradation c linearly decreased with CL extract doses (R² = 0.44, P = 0.0065). For the effective rumen degradability of N, a linear reduction (R² = 0.94, P < 0.0001) was observed. The in vitro intestinal digestibility of protein (ivID) quadratically decreased (R² = 0.99, P < 0.0001) with TP inclusion and the rumen undegradable protein (RUP) showed a quadratic increase (R² = 0.94, P = 0.0417). Total intestinal protein availability, computed from the RUP and ivID, linearly decreased with TP inclusion level (R² = 0.45, P = 0.0033).