幼蛇的冬养

出生第一年的幼蛇宜在室内越冬 ,为了有效缩短蛇的育成周期 ,可以打破冬眠期转为冬季室内养殖。第一年的幼蛇因没有冬眠适应性 ,可在保证幼蛇所需的温度、湿度条件及能够供应充足的活体小动物 ,就可以进行冬季室内养殖 ,以下简称冬养。　　幼蛇冬养的温度宜在 2 0～ 2 8℃之间 ,湿度应在 50 %～ 60 %左右 ,幼蛇大多采取人工灌喂混合饲料或流汁饲料的方法 ,来解决其所需的营养和消耗。一般 5～ 7天灌喂 1次 ,喂时可使用中型的 (容量为 2 0 ml)钝头注射器 ,每次灌喂标有刻度的 1～ 2小格 ,操作时需两人进行 ,一人持蛇使之不动 ,另一人轻掰蛇口…     

温湿度对越冬异色瓢虫(Harmonia axyridis)存活的影响

为了明确温度和相对湿度对越冬异色瓢虫存活的影响,采用二次正交旋转组合设计,试验了秋冬季收集的异色瓢虫自然种群在不同温湿度组合下,经不同时间后的存活率和存活时间。结果表明,在试验条件下最佳温湿度组合为０℃,ＲＨ７５％。此条件下处理６个月以上时存活率仍达８０％以上,存活时间近９ｄ;温度对异色瓢虫的存活影响最大,湿度次之,温湿度的交互作用最不重要;由试验结果建立了不同处理时间下,温湿度与存活率和存活时间之间关系的一系列二次回归方程。对方程分析表明：０～４℃为异色瓢虫越冬的适宜温度,小于０℃的低温引起存活率下降和存活时间缩短,ＲＨ７０％～８０％为异色瓢虫越冬的适宜湿度,低于ＲＨ６０％和高于ＲＨ９０％不利于存活;处理后的异色瓢虫的存活率和存活时间随着处理时间的延长而减小。但处理时间为６个月以内时,存活率的下降幅度较小     

角倍蚜越冬世代的发育起点温度和有效积温

五倍子系中国特产,是重要的化工和医药原料。角倍蚜Schclechtendaliachinesis（Bell）是生产五倍子的最主要致瘿蚜种。恒温试验表明,其越冬世代有翅型随温度从4.5℃升至18.0℃,平均世代历期从266.2天缩短至76.6天,世代发育起点温度为-1.4℃,有效积温为1512.9日度;无翅型随温度从7.5℃升至22.0℃,平均世代历期从118.8天缩短至29.4天,世代发育起点温度为2.2℃,有效积温为557．4日度。     

苹果绵蚜蚜小蜂发育历期、发育起点温度和有效积温的研究

本文以苹果绵蚜为繁殖寄主,研究了苹果绵蚜蚜小蜂在不同温度下的发育历期、发育起点温度和有效积温。结果显示:苹果绵蚜蚜小蜂的发育历期随温度的升高而缩短,最适发育温度为21℃-27℃。山东地区越冬代苹果绵蚜蚜小蜂打破滞育的发育起点温度为雌蜂8.58℃,雄蜂8.22℃;有效积温为雌蜂148.72日度,雄蜂154.68日度。非越冬代苹果绵蚜蚜小蜂在卵-羽化阶段发育起点温度为雌蜂5.62℃,雄蜂5.55℃;有效积温为雌蜂284.40日度,雄蜂为295.61日度。并推测了2008年济南地区苹果绵蚜蚜小蜂发生代数和越冬代羽化时间,与实测情况基本相符。     

南昌地区灰飞虱的生活史、繁殖和越冬生物学特性

为了探明灰飞虱Laodelphax striatellus (Fallén)在南昌地区的生物学特性, 本研究在实验室和自然条件下系统调查了该虫的年生活史, 温度对其生长发育、 繁殖、 性比及翅型分化的影响, 及其越冬生物学。结果表明, 灰飞虱在南昌一年发生4~7代。在18~32℃, 卵的发育历期随温度升高逐渐缩短。若虫的发育历期在18~28℃随温度升高逐渐缩短, 但若虫的发育历期在30和32℃时显著长于28℃的发育历期（P=0.000﹤0.05）。越冬个体的若虫期为143~187 d。卵和若虫的发育起点温度分别为10.17℃和7.51℃。在室外, 7月中旬高温下孵化的第4代若虫的发育历期也明显延长, 显示了高温诱导的夏季休眠现象。在18~28℃, 产卵前期随温度升高而逐渐缩短, 当温度上升到30℃时, 其产卵前期比26和28℃下有所延长。产卵期在22℃最长, 30℃下最短。成虫在20~24℃下的寿命最长。在28℃下, 平均每雌产若虫量最大。不论在室内还是在室外, 雌雄比均接近1∶1。在18~32℃, 羽化的成虫均以长翅型占绝对优势。在自然条件下, 越冬代和第6代羽化的成虫以短翅型占优势, 其他各代仍以长翅型占优势。在自然条件下, 9月中旬孵化的若虫就有少量个体滞育越冬, 10月中旬后孵化的若虫全部进入越冬。越冬若虫的龄期为1-5龄。本研究为该虫发生的预测及有效防控提供基础资料。     

眼镜蛇在黑龙江省大庆市试养成功

黑龙江省大庆市庆华玻璃器皿厂工人兰海双通过提高蛇箱温度的方法,打破了蛇的冬眠习性,使南蛇北养首次获得成功。饲养５个月后,最大蛇的体长达５８ｃｍ,体重２４５ｇ,最小蛇的体长４８ｃｍ,体重２１８ｇ,且在饲养过程中,无蛇死亡,成活率达到１００％。兰海双系该...     

低温和光周期对绿盲蝽越冬卵滞育解除和发育历期的影响

为了探讨温度和光周期对绿盲蝽Apolygus lucorum Meyer-Dür越冬卵滞育解除和发育历期的影响, 系统调查了绿盲蝽越冬卵在不同温度和不同光照组合下的孵化率和孵化时间, 结果显示：绿盲蝽的越冬卵均为滞育卵,低温和光周期对绿盲蝽越冬卵的滞育解除均有影响。2℃的低温处理能够显著促进其滞育解除,在0~65 d范围内,随着低温处理时间增长,其滞育解除时间缩短,未经低温处理的越冬卵T₅₀为68.5 d,低温处理65 d的T₅₀为12.25 d,绿盲蝽越冬卵在2℃低温处理65 d后完全解除滞育;在0~40 d范围内,低温处理时间越长,绿盲蝽越冬卵的孵化率越高,在25℃、全光照的条件下不经低温处理的孵化率为68.65%,低温处理40 d后在25℃的条件下的孵化率达到99.46%。在20~26℃范围内,绿盲蝽越冬卵的滞育后发育历期随着温度的上升而缩短, 随着光周期的延长而缩短。结果说明低温处理能够提高绿盲蝽越冬卵滞育解除率,但不是其滞育解除的必要条件,低温处理与自然变温对绿盲蝽滞育解除的作用相似;高温和长光照能够促进绿盲蝽的滞育解除,缩短发育历期。     

两种松毛虫黑卵蜂的初步研究

1.本文主要研究松毛虫卵的两种黑卵蜂(Telenomus dendrolimusi Chu及Teleno-mus sp.,Scelionidae,Hymenoptera)的生物学特性;及1954—55年江苏南京和浙江常山等地林间的寄生情况,同时对松毛虫卵及黑卵蜂的冷藏也进行了试验。 2.两种黑卵蜂中,松毛虫黑卵蜂(Telenomus dendrolimusi Chu)与毒蛾黑卵蜂(Telenomus sp.)不但在形态上有所不同。而且在生活习性及各期虫态对低温的反应上亦各异,证明它们确系不同的两种。毒蛾黑卵蜂在我国系首次记载寄生于松毛虫卵中,现知在江苏南京、江宁,浙江常山及广东广州均有分布,在南京的黑卵蜂中占80％以上。 3.毒蛾黑卵蜂以幼虫态在寄主卵内越冬,利于冬季生存。越冬代成虫羽化时间接近松毛虫第1代卵出现期。且有松毒蛾(Lymantria sp.,Lymantriidae,Lepidoptera)作为补充寄主。这些特性均较松毛虫黑卵蜂为优。 4.室内外饲育结果,知松毛虫黑卵蜂在南京年可发生10—12代,毒蛾黑卵蜂年有8—9代,性比雌蜂占80％左右,毒蛾黑卵蜂破坏寄主卵粒平均为30粒左右比松毛虫黑卵蜂平均15粒左右为高。产卵期较集中,且在室内容易繁殖。 5.从发育1天的松毛虫卵冷藏于4℃冰箱中1个月不影响毒蛾黑卵蜂的寄生发育。毒蛾黑卵蜂在4℃冰箱中冷藏,以老熟幼虫为最好,冷藏1个月后,对其产生后代数无影     

黑广肩步甲主要生物学特性及卵的有效积温

研究了黑广肩步甲Calosoma maximociczi Morawitz各虫态的主要生物学特性及其卵的发育起点温度与有效积温.在山东地区,该虫1年发生1代,以成虫在土壤中越冬.成虫在5月中旬至10月上旬发生,6月初开始产卵,卵的发育起点温度为14.66℃,有效积温41.7日度,在25℃下卵期平均为3.69±0.25d;幼虫共3龄,历期分别为3d～5d、4d～5d;平均气温28℃下,预蛹期约为8d～14d,蛹期为10d～15d.成、幼虫以多种鳞翅目幼虫为食.     

温度对大猿叶虫成虫繁殖和繁殖后滞育的影响

大猿叶虫Colaphellus bowringi Baly是十字花科蔬菜上的重要害虫。在田间,该虫的繁殖期出现在春季和秋季,以成虫在土中越夏和越冬。本试验在光周期L∶D=16∶8条件下,系统调查了不同温度(20、25和28℃)对大猿叶虫非滞育成虫繁殖的影响。结果表明:每雌平均日产卵量在28℃最大(51.24±2.90)粒,显著高于25℃和20℃的(39.57±2.86)粒和(31.53±2.02)粒,但由于28℃下的产卵持续时间明显短,导致了总产卵量在这3种温度间没有显著差异;28℃下的卵孵化率低于20℃和25℃,但没有显著差异;随着温度的升高,成虫寿命逐渐缩短,20℃与28℃间的雌虫寿命存在显著差异,20℃与25℃,28℃的雄虫寿命存在显著差异;在20、25、28℃下,均有30%的个体经历一段时间繁殖后进入滞育,其滞育前的产卵持续时间随着温度的升高而明显缩短,总产卵量也随着温度的升高而下降。     

Body Morph Assessment: Preliminary Report on the Development of a Computerized Measure of Body Image

STEWART, TIFFANY M., DONALD A. WILLIAMSON, MONIQUE A. M. SMEETS, AND FRANK L. GREENWAY. Body morph assessment: preliminary report on the development of a computerized measure of body image. Objective: To develop a prototype of the Body Morph Assessment (BMA), and to test the reliability and validity of this new measure of body image. The BMA is a realistic and relatively simple procedure that uses computer morphing for the assessment of body image. For the purposes of this preliminary study, a prototype of the BMA was developed for usage with white women ranging from very thin to obese. Research Methods and Procedures: A total of 72 subjects participated in tests of reliability, content, and convergent validity of the BMA. Results: The reliability and validity of the BMA was supported by the results of this study. In a test of convergent validity, the measures of current, ideal, and reasonable body size were positively correlated with their equivalents from a similar body image assessment procedure. In addition, reliability coefficients were found to be satisfactory for all variables. Participants found the human figural stimuli to be realistic. Discussion: These preliminary findings support the reliability and validity of the BMA with white women. Given these positive findings, we plan to extend the procedure to males and to other racial and ethnic groups.     

Regional body volumes, BMI, waist circumference, and percentage fat in severely obese adults

Objective: This study presents total body volume (TBV) and regional body volume, and their relationships with widely used body composition indices [BMI, waist circumference (WC), and percentage body fat (% fat)] in severely obese adults (BMI ≥35 kg/m²). Research Methods and Procedures: We measured TBV, trunk volume (TV), arm volume (AV), leg volume (LV), and WC and estimated % fat in 32 severely obese persons with BMI 36 to 62 kg/m² (23 women; age, 19 to 65 years; weight, 91 to 182 kg) and in 58 persons with BMI <35 kg/m² (28 women; age, 18 to 83 years; weight, 48 to 102 kg) using a newly validated 3‐day photonic image scanner (3DPS, Model C9036–02, Hamamatsu Co., Japan) and calculated TV/TBV, AV/TBV, and LV/TBV. Results: Men had significantly larger TBV and higher TV/TBV and AV/TBV, but significantly lower LV/TBV than women, independently of BMI. TV/TBV increased while AV/TBV and LV/TBV decreased with increasing BMI, WC, and % fat, and the rate of increase in TV/TBV per % fat was significantly greater in severely obese individuals than in individuals with BMI <35 kg/m². The relationships for TBV with % fat were much lower than with BMI or WC. Conclusion: Body volume gains were mainly in the trunk region in adults, irrespective of sex or BMI. For a given BMI, WC, or % fat, men had a significantly larger TV than women. The implication is that men could have higher health risks due to having higher trunk body weight as a proportion of total body weight compared with severely obese or less severely obese women.     

Effect of Scalp and Facial Hair on Air Displacement Plethysmography Estimates of Percentage of Body Fat

Objective: The objective of this study was to determine the effect of body hair (scalp and facial) on air displacement plethysmography (BOD POD) estimates of percentage of body fat. Research Methods and Procedures: A total of 25 men (31.4 ± 8.0 years, 83.4 ± 12.2 kg, 181.8 ± 6.9 cm) agreed to grow a beard for 3 weeks to participate in the study. Total body density (g/cm³) and percentage of body fat were evaluated by BOD POD. To observe the effect of trapped isothermal air in body hair, BOD POD measures were performed in four conditions: criterion method (the beard was shaven and a swimcap was worn), facial hair and swimcap, facial hair and no swimcap, and no facial hair and no swimcap_. Results: The presence of only a beard (facial hair and swimcap) resulted in a significant underestimation of percentage of body fat (16.2%, 1.0618 g/cm³) vs. the criterion method (17.1%, 1.0597 g/cm³, p < 0.001). The effect of scalp hair (no swim cap worn) resulted in a significant underestimation in percentage of body fat relative to the criterion method, either with facial hair (facial hair and no swimcap; 14.8%, 1.0649 g/cm³) or without facial hair (no facial hair and no swimcap; 14.8%, 1.0650 g/cm³, p < 0.001 for both). Discussion: A significant underestimation of percentage of body fat was observed with the presence of facial hair (～1%) and scalp hair (～2.3%). This underestimation in percentage of body fat may be caused by the effect of trapped isothermal air in body hair on body‐volume estimates. Thus, excess facial hair should be kept to a minimum and a swimcap should be worn at all times to ensure accurate estimates of body fat when using the BOD POD.     

Physical Activity,TV Viewing,and Weight in U.S. Youth: 1999 Youth Risk Behavior Survey

Objective: To examine the relationship between physical activity, TV watching, and weight in U.S. youth ages 14 to 18 years. Research Methods and Procedures: Data from a nationally representative sample of 15,143 U.S. high‐school students participating in the 1999 Centers for Disease Control and Prevention (CDC) Youth Risk Behavior Survey were examined. Prevalence rates of participation in moderate physical activity (MPA), vigorous physical activity (VPA), and television watching (TV) were determined. The association between MPA, VPA, TV and the body mass index (BMI) and overweight status (BMI ≥85th percentile of age‐ and sex‐specific CDC/National Center for Health Statistics reference values) were examined by analysis of covariance and logistic regression. Results: Overall, 45% reported participating in MPA ≥3 d/wk, 65% reported participating in VPA ≥3 d/wk, and 25% reported watching TV ≥4 h/school day. Boys reporting six to seven bouts of MPA had a significantly lower BMI compared with boys reporting three to five or less than two. The mean BMI differed significantly between the lowest and highest levels of MPA groups in girls. The mean BMI was significantly lower in the highest VPA group compared with the other two groups in both sexes. There was a significant graded response for BMI across all levels of TV. Decreased levels of MPA and 3 to 4 days of VPA were significantly associated with an increased risk of overweight in boys when compared with those engaging in 6 to 7 d/wk (odds ratio = 1.26 to 1.37). A graded response existed between TV and overweight in both sexes. Boys and girls were ～20% to 25% less likely to be classified as overweight if they reported 2 to 3 hours of TV per day and ～40% less likely to be classified as overweight if they reported ≤1 hour of TV per day compared with those who watched ≥4 hours of TV. In general, youth who engaged in less physical activity watched more TV per week. Discussion: Increased levels of physical activity are associated with a lower BMI and less TV watching. However, the relationship between TV watching and weight status is more pronounced.     

植物油体研究进展

油体是生物体细胞中一种重要的细胞器结构,由单层磷脂酸膜包裹中性脂肪酸形成,膜上镶嵌有决定油体性质的多种膜蛋白。油体在能量储存、细胞生殖分化、抗病抗寒和发育调控等多种生命活动中起重要作用。该文对植物油体的结构、生物学功能、不同组织中油体的形成情况以及油体膜蛋白的研究进展进行了多方位概述和总结,以期为后续研究提供有益的参考。     

Reproducibility of Dual-Energy X-ray Absorptiometry Measurements in Prepubertal Girls

Objective : Regulation of growth and development, clinical assessment, and obesity are among the areas of nutritionrelated research, wherein accurate assessment of body composition is important. We want to test the hypothesis that dual-energy X-ray absorptiometry (DXA) measurements are reproducible in healthy girls. Research Methods and Procedures : We determined total body composition measurements in healthy prepubertal girls using DXA twice, 6 weeks apart. Results : We studied 61 healthy, normal-weight, prepubertal girls, aged 4.8 years to 10.3 years. The girls' DXA-derived mean weight between visits 1 and 2 significantly increased (27.14 kg vs. 27.80 kg, P<0.0001). The increased weight was due to significant increases in total body fat-free mass (FFM) (19.53 kg vs. 19.89 kg,P<O.001), total body bone mass (1.05 kg vs. 1.07 kg, P<0.0001), and total body fat mass (7.61 kg vs. 7.91 kg,P<0.03). The girls' DXA-derived mean total trunk mass between visits 1 and 2 significantly increased (11.23 kg vs. 11.63 kg, p<<0.0001), as did total leg mass (9.33 kg vs. 9.53 kg, p<<0.001), although no significant differences were observed in total arm mass (2.52 kg vs. 2.54 kg, p< = 0.37). The Pearson coefficient of correlation (r) and total coefficient of variation (CV) for intraindividual measurements by DXA were: weight—r = 0.99, CV= 1.97%; total body FFM—r = 0.96, CV = 2.30%; total body bone mass—r = 0.99, CV = 2.08%; total body fat mass—r = 0.96, CV = 6.55%; percentage total body fat— r = 0.91, CV = 5.69%; total trunk mass—r = 0.96, CV = 3.59%; total arm mass—r = 0.95, CV = 4.09%; and total leg mass—r = 0.99, CV = 2.75%. Discussion : Total body FFM, total body bone mass, total body fat mass, percentage of total body fat mass, as well as regional mass determinations by DXA, were highly reproducible in healthy, normal-weight, prepubertal girls. We highly recommend the use of DXA for total body composition studies in girls aged 5 years to 10 years.     

Measurement of body composition in response to a short period of overfeeding

Background

Obesity and overweight are increasing in prevalence in developed countries as a result of changing dietary habits and a lack of physical activity. The purpose of the present study was to evaluate the changes in body composition during short-term overfeeding using the three-component model, which is composed of fat mass (FM), total body water (TBW), and fat-free dry solids (FFDS).

Methods

Ten healthy men completed 3 days of overfeeding during which they consumed 1,500 kcal/day more energy than consumed in their normal diets. Body composition was evaluated at three time points: the day before and after their normal diets and the day after the 3-day overfeeding diet.

Results

Before and after their normal diets, there were no significant differences in body weight and composition, but after 3 days of overfeeding, body weight, TBW, and FFDS increased 0.7, 0.7, and 0.2 kg, respectively (P <0.0001). There was no significant difference in FM between the normal and overfeeding diets.

Conclusion

This study suggests that TBW gain contributes to weight gain following a short-term overfeeding.     

Sex,Race/Ethnicity,Socioeconomic Status,and BMI in Relation to Self‐Perception of Overweight

Objective: To compare the self‐perception of overweight in the study population according to sex, race/ethnicity, and socioeconomic status and to compare the self‐perception of overweight among individuals classified as normal weight, overweight, and obese. Research Methods and Procedures: Data from 5440 adults who participated in the 1994 to 1996 Continuing Survey of Food Intakes by Individuals and the Diet and Health Knowledge Survey conducted by the U.S. Department of Agriculture were analyzed. Data for analysis included self‐perceived weight status, self‐reported weight and height, and demographic and socioeconomic data. Underweight individuals, defined as those with a body mass index <18.5 kg/m², were excluded from the analysis. Results: Self‐perception of overweight was more common in women compared with men and in whites compared with blacks or Hispanics. Both the correct and incorrect perception of overweight was more common in normal weight and overweight white women compared with black women. More overweight and obese white men correctly perceived their overweight status compared with black men. Multiple logistic regression showed that the odds ratio of perceived overweight was significantly higher in women, whites, and individuals with higher body mass index, higher income, and higher education. Discussion: Self‐perceived overweight varied by sex, race/ethnicity, and socioeconomic status. Erroneous perception of body weight may have important health and behavioral implications. In particular, a considerable proportion of overweight men may be at risk of obesity if they continue to perceive themselves as having normal weight.