INTERACTION BETWEEN GENOTYPES AT THE DIAZINON-RESISTANCE LOCUS OF THE AUSTRALIAN SHEEP BLOWFLY,LUCILIA CUPRINA. FACILITATION OF DEVELOPMENT OF SUSCEPTIBLE GENOTYPES

The survival of larvae with susceptible (+ +) genotypes at the diazinon-resistance locus of the Australian sheep blowfly, Lucilia cuprina is facilitated by prior conditioning of diazinon-containing media by heterozygote (R+) or resistant (RR) larvae. The effect is not observed on media without diazinon. Conditioning by + + genotypes does not affect subsequent development of susceptible larvae and the viability of R + and RR larvae is unaffected by conditioning of the media. Similar results are observed when the medium is conditioned with crushed larvae of the three genotypes. The development of + + larvae is enhanced only on media containing diazinon to which R + or RR crushed larvae are added. The results for other comparisons are equivalent for conditioned or unconditioned media. The number of crushed ++, R +, or RR larvae added to the medium containing diazinon does not affect the proportion of + + eggs that develop through larval and pupal stages to emerge as adults. The rate of development of the + + genotype is, however, positively correlated with the number of crushed R + or RR larvae added.     

Quantitative relationships between the ingestion of protein-rich material and ovarian development in the Australian sheep blowfly,Lucilia cuprina (Wied.)

The mature ovaries accounted for about 25% of dry weight and 30% of the protein content of wild-type (anautogenous) females of L. cuprina which had fed ad lib. on liver. The protein content of gravid females was 50% greater than at emergence. Protein ingested during the adult stage, therefore, plays an important role in ovarian maturation. The protein content of the ovaries of females fed measured amounts of liver exudate was from 37 to 52% of the amount of protein ingested.

Only limited ovarian development occurred in females fed only protein (high MW fraction of liver exudate or bovine serum albumin). The presence, in addition, of low MW components (low MW fraction of liver exudate or a salt mixture) was necessary for ovarian maturation. Quantitative feeding showed that the high and low MW fractions of liver exudate were, respectively, superior to bovine serum albumin and the salt mixture, which was based on the cation analysis of the low MW fraction of the exudate.     

性成熟草鱼卵巢发育的年周期变化

产卵前的卵巢同时含有大量4时相卵母细胞及少量2时相和3时相卵母细胞。产后2时相及3时相卵母细胞增多而4时相卵母细胞骤减,8月份4时相卵母细胞的数量又增多,约占卵巢体积的80％,及至11月份其数量又下降。自11月至翌年1月,卵巢中3时相卵母细胞增多而4时相卵母细胞则消失不见。至2月份,新的4时相卵母细胞又开始出现并逐渐增多。性成熟草鱼的卵巢以如此规律周而复始地产生成熟的卵子。卵巢中卵母细胞的发育是不同步的。但在产卵前有大量的3时相卵母细胞向4时相演化,同时有为数不少的发育中的2时相卵母细胞存在。产后卵巢中亦同时存在不同发育时期的卵母细胞。     

INDUCTION OF OVARIAN DEVELOPMENT IN AUTOGENOUS AEDES ATROPALPUS BY JUVENILE HORMONE AND 20-HYDROXYECDYSONE

Aedes atropalpus is an autogenous mosquito characterized by a first gonadotropic cycle which results in approximately 200 mature oocytes without a bloodmeal. Ovarian development is completely inhibited if these animals are decapitated or ligated between the thorax and abdomen shortly after adult emergence. Injection of 4.8 ng of 20-hydro- xyecdysone into decapitated females 12 h after eclosion restores ovarian development in all females so treated. However, the same amount of 20-hydroxyecdysone injected into isolated abdomens obtained shortly after adult emergence had no discernible effect on vitellogenesis. In contrast, all abdomens which received 0.5 ng of topically applied JH I followed by the injection of 4.8 ng 20-hydroxyecdysone produced mature oocytes. Isolated abdomens were also capable of oocyte maturation when treated with excess amounts of JH alone; JH I was the most effective followed by JH II and then JH III.

Polyacrylamide gel electrophoretic analysis of vitellin extracted from the ovaries of hormonally-treated animals did not reveal any qualitative differences compared to intact normal controls. However, less yolk protein was present in the former. This was verified by counting the number and measuring the size of ovarian follicles in individual females.     

LABORATORY OBSERVATIONS ON THE TENERAL PERIOD IN SHEEP BLOWFLIES,LUCILIA CUPRINA (DIPTERA: CALLIPHORIDAE)

The teneral period following emergence is defined for Lucilia cuprina in terms of activity measured using electronic actographs, volume of thoracic flight muscle, and the area of flight muscle attachment on the endo-skeletal mesothoracic post-phragmata. All three quantities are highly inter-correlated and show a rise to an asymptote following emergence. This pattern allows the teneral period at 26°C to be defined as the 3 days following emergence. The application of this figure to field situations is discussed and it is concluded that some care must be exercised in this respect. The most important conclusion emerging is that the teneral period may be identified using either behavioural or morphological characteristics, whichever is the more convenient.     

拟目乌贼卵子发生与卵巢发育

为了丰富拟目乌贼(Sepia lycidas)生物学资料, 为人工育苗与养殖提供理论依据, 采用解剖学和组织学的方法, 对水泥池养殖条件下拟目乌贼卵子发生和卵巢发育进行了研究。结果表明: 经过6个月水泥池养殖, 平均体重为256.34 g, 最大体重达到457.08 g, 个别发育成熟, 绝大部分未达性成熟。卵子发生不同步, 根据细胞形态、细胞大小、滤泡细胞形态和卵黄形成情况可分为卵原细胞阶段(卵原细胞期)、原生质生长阶段(无滤泡期、单层滤泡期和双层滤泡期)、间质生长阶段(滤泡内折早期、滤泡内折中期和滤泡内折晚期)和营养质生长阶段(卵黄发生早期、卵黄发生晚期和成熟期), 共4个阶段10个时期。卵巢发育根据外观形态、性腺指数变化和切面上各期细胞所占的比例, 可分为形成前期、形成期、小生长期、大生长期、成熟前期和成熟期6个时期。拟目乌贼繁殖周期为一年。       

卵胎生硬骨鱼褐菖()卵巢的周期发育研究

经组织学观察表明,褐菖()(Sebastiscus marmoratus)的卵巢由卵巢壁、卵巢绒毛和卵巢腔构成.卵巢壁的肌层较厚,卵巢上皮具分泌功能.卵巢绒毛位于卵巢腔中,呈树枝状.在卵巢绒毛上分布着滤泡.滤泡由卵母细胞和滤泡膜构成.滤泡膜包括内层的颗粒层和外层的鞘膜层.鞘膜层上有丰富的毛细血管.滤泡靠滤泡柄悬挂在卵巢绒毛上.卵巢发育分7个时期.成熟卵排放在卵巢腔中受精.胚胎浸置在卵巢液中发育.卵巢发育、卵巢成熟系数和卵巢壁厚度随季节呈年周期变化.     

卵胎生硬骨鱼褐菖鲉卵巢的周期发育研究

经组织学观察表明 ,褐菖鲉 (Sebastiscusmarmoratus)的卵巢由卵巢壁、卵巢绒毛和卵巢腔构成。卵巢壁的肌层较厚 ,卵巢上皮具分泌功能。卵巢绒毛位于卵巢腔中 ,呈树枝状。在卵巢绒毛上分布着滤泡。滤泡由卵母细胞和滤泡膜构成。滤泡膜包括内层的颗粒层和外层的鞘膜层。鞘膜层上有丰富的毛细血管。滤泡靠滤泡柄悬挂在卵巢绒毛上。卵巢发育分 7个时期。成熟卵排放在卵巢腔中受精。胚胎浸置在卵巢液中发育。卵巢发育、卵巢成熟系数和卵巢壁厚度随季节呈年周期变化。     

Do protein-limited female Lucilia cuprina (Diptera: Calliphoridae) obtain a nutritional benefit from mating?

Abstract. Cohorts of adult female Lucilia cuprina Wiedemann (Diptera: Calliphoridae) were fed a single 5 μl droplet of liver exudate after which half the females were allowed to mate and the other half left as virgins. Females were housed individually with water and sucrose for between 4 and 7 days after mating. Females were dissected to record the level of ovarian development and the size of their primary oocytes. Mating did not give protein-limited females any significant nutritional benefit in terms of either increased oocyte development, yolk deposition or oocyte size. Hence, it is concluded that male L.cuprina do not provide females at mating with any obvious material benefits beyond their sperm.     

卵巢催乳素受体mRNA在小鼠卵泡发育及排卵过程中的表达

目的探讨卵巢催乳素受体(Prolactin receptor,PRLR)mRNA在小鼠不同发育阶段及排卵过程中的表达情况。方法选择不同发育时期的昆明小鼠,以及性未成熟昆明小鼠予以PMSG-HCG(Pregnancy Mare Serum Gonadotro-phin-Humane chorionic gonadotrophin,孕马血清促性腺激素-人绒毛膜促性腺激素)序贯处理,采用实时定量聚合酶链反应(Real-Time Polymerase Chain Reaction,Real-Time PCR)检测小鼠卵巢中PRLR mRNA的表达。结果PRLR mR-NA的表达水平随小鼠的不断发育而显著性升高,PRLR在6周龄小鼠卵巢中的表达量是3周龄小鼠的3.86倍(P0.01),11周龄与33周龄小鼠的表达水平分别是3周龄小鼠的19.67倍、19.81倍(P0.01);PMSG处理后12h,PRLR表达水平是对照组的1.44倍(P0.05),24h、48h后分别达到5.48倍和7.14倍(P0.01),HCG处理后4h、8h、12h,PRLR表达水平有所下降,但仍高于对照组(P0.01),24h、48h后其表达水平再次升高,分别是对照组的5.64倍和6.04倍。结果 PRLR对小鼠卵泡的生长、发育及其黄体形成与维持发挥重要作用。