Studies on ticks of veterinary importance in Nigeria. VIII. Differences observed in the biology of ticks which fed on different domestic animal hosts

Ticks of the species Amblyomma variegatum (Fabr.), Boophilus decoloratus (Koch), Boophilus geigyi Aeschl. et Morel, and Hyalomma rufipes Koch were detached from cattle, sheep and horses and the influence of these various hosts on the biology of ticks was investigated. No A. variegatum was found in horses. The parameters studied were preoviposition and oviposition periods, ovipositional capacity, eclosion period, hatching patterns, egg sizes and temperature effect. Although the preoviposition and eclosion periods were similar in each tick species irrespective of the host from which the adults were detached, the oviposition period was longest among ticks detached from cattle and least among those detached from horses. The ticks engorged on cattle also laid the highest number of eggs and those which engorged on horses laid the least number. The hatching pattern of the eggs in any tick species was not influenced by the host from which the female was detached. The lengths of eggs of the ticks whose adults were detached from horses were generally smaller than those detached from cattle and sheep. Temperature affected the adult females detached from cattle, sheep and horses equally and this was also true of the larvae they produced. The practical field applications of these results are discussed.     

The activity of amitraz against infestations of Rhipicephalus appendiculatus

Tick-infested adult cattle were hand sprayed with solutions containing 178 or 250 mg amitraz litre^?1, prepared from a miscible oil concentrate formulation. Both concentrations achieved clearance of infestation within 7 h of spraying. All stages of tick, collected from both sprayings, subsequently died with the exception of two engorged nymphs, which moulted successfully, and six half-fully engorged females, which all laid small batches of eggs. The eggs from the ticks treated at the higher rate failed to hatch. Expulsion of adult Rhipicephalus appendiculatus, applied daily to a single bovine which had been sprayed once at the higher rate, ceased on the 11th day after spraying. All ticks expelled from the animal died within 24 h. First feeding on the animal was visible on day-13 and fully engorged females were first observed 18 days after spraying.     

Studies on ticks of veterinary importance in Nigeria: intrinsic factors influencing oviposition and egg-hatch of Amblyomma variegatum under natural conditions

During the peak of rains of 1983, 1984 and 1985 in the forest zone of Nigeria, female Amblyomma variegatum engorged to various weights were subjected to different experiments for the purpose of observing the intrinsic factors which influence oviposition and egg-hatch under natural conditions. Two types of oviposition patterns were observed. New terms were introduced to quantify the relationships between the daily weight loss and daily number of eggs oviposited by a tick. These terms are "actual mass", "convertible blood mass", "oviposition efficiency" and "mass conversion rate". A major advantage of adopting the "oviposition efficiency" and "mass conversion rate" is that they relate directly to the measure of the metabolic activity utilized by the tick for the process of oviposition. The entity "convertable blood mass" also enables recognition of individual capability in the utilization of blood mass for oviposition. Investigation on the relationship of weight of eggs with sequence of oviposition showed that eggs were heavier when few eggs were laid than when numerous eggs were oviposited. The heaviest eggs were laid towards the end of oviposition. Two types of relationship were found to exit between the sequence of oviposition and the eclosion period of eggs. Adult A. variegatum engorged to more than 2.49 x were affected by immersion in water for longer than 7 days. Such ticks died without ovipositing and the water in which they were submerged became dark-red. Eggs immersed in water for periods ranging from 1-7 days hatched in about the same number of days as control eggs and their viability in terms of percent-hatch was not affected.     

苏丹草和香根草作为诱虫植物对稻田二化螟种群的抑制作用评估

室内测试了苏丹草和香根草对二化螟的产卵选择性和幼虫存活的影响,在田间进行了苏丹草和香根草控害效果的初步试验。结果表明,二化螟雌成虫对苏丹草和香根草均表现出较强的产卵选择性,产在苏丹草和香根草上的卵量分别是产在水稻上的3.02和4.56倍。两种诱虫植物均对二化螟幼虫具致死作用,二化螟幼虫在两种寄主上不能完成生活史。田间试验表明两种诱虫植物围绕的水稻小区内二化螟枯心率显著低于试验区外20m的对照小区。     

Modulation of human lymphocyte proliferation by salivary gland extracts of ixodid ticks (Acari: Ixodidae): effect of feeding stage and sex

Ixodid ticks remain attached to their hosts for several days to weeks. During this extended feeding process new proteins involved in the modulation of host immune responses are expressed in tick salivary glands. In our study a stimulatory or inhibitory effect of salivary gland extracts (SGE) of unfed and partially fed female Ixodes ricinus (Linnaeus, 1758), female and male Amblyomma variegatum (Fabricius, 1794) and Rhipicephalus appendiculatus Neumann, 1901 ticks on human lymphocyte proliferation induced by Concanavalin A (ConA) and phytohaemagglutinin (PHA), respectively, was investigated. SGE of all female ticks examined suppressed proliferation of ConA-induced lymphocytes; highly significant suppression was observed in the presence of unfed I. ricinus and 9-day fed A. variegatum SGE. SGE of partially fed A. variegatum and I. ricinus females suppressed PHA responses of lymphocytes. Lymphocytes showed reduced PHA and ConA responses in the presence of SGE of unfed and 2-day fed R. appendiculatus females, while SGE of 6-day fed females enhanced PHA responses, but reduced their ConA responses; generally SGE of 2-day fed females displayed the strongest inhibition. Amblyomma variegatum male SGE slightly enhanced PHA, but significantly reduced ConA responses of lymphocytes and their inhibitory effect increased during feeding. SGE of unfed and 2-day fed R. appendiculatus males enhanced PHA and ConA responses and those of 6-day fed males suppressed lymphocyte proliferation. The results suggest that (i) species- and sex-specific differences exist in the effects of tick salivary gland antigens on human lymphocyte proliferation and (ii) effect of SGE on human lymphocyte responses to mitogens varies depending on the tick feeding status.     

副珠蜡蚧阔柄跳小蜂MetaphyCUS parasaissetiae Zhang and Huang生物学特性的研究

副珠蜡蚧阔柄跳小蜂Metaphycus parasaissetiae Zhang and Huang是新发现的橡副珠蜡蚧成虫内寄生蜂,自然寄生率约为15.68%。实验室内对其形态、发育、繁殖、存活、行为等生物学特性进行了观察。结果表明,在26±1℃,RH70%±5%条件下,每头寄主出蜂4.5头,雌性比例80.6%;雌蜂生殖系统解剖发现,未交配雌蜂卵巢内的卵经1d可发育成熟,但同一雌蜂卵巢内卵粒之间发育程度不一致;该蜂完成一个世代需15～19d,但幼虫蜕皮现象不明显;该蜂可营孤雌产雄生殖,孤雌羽化后24h内即可产卵,平均每头寄主可出雄蜂5.3头;雌蜂交配后24h内即可产卵,产卵期1～17d;1头已交配雌蜂可寄生1～10头寄主,一生产卵3～76粒,每日平均产卵量为8.2±4.0粒;雌、雄成蜂平均寿命均不超过3d,补充蜂蜜水可延长雌、雄成蜂的寿命。     

Bacterial isolation from and transmission by Boophilus decoloratus and Boophilus geigyi

Bacteria were isolated from the haemolymph of Boophilus decoloratus and Boophilus geigyi which had engorged on trade cattle in Nigeria. All the genera of the bacteria were also isolated from the eggs which they laid although some of them were missing from the larvae which eventually hatched. When clean rabbits were inoculated with some genera of bacteria and clean, laboratory bred larvae of B. decoloratus and B. geigyi fed on them, the same genera of bacteria were subsequently isolated from the haemolymph of the engorged adults, the eggs they produced and the larvae which hatched from them. Staphylococcus pyogenes and Pseudomonas aeruginosa were consistently encountered in the haemolymph, eggs and larvae of both Boophilus species while Proteus mirabilis was additionally consistent in B. geigyi.     

Clutch size decisions of <Emphasis Type="Italic">Cotesia glomerata</Emphasis>, a gregarious parasitoid of <Emphasis Type="Italic">Pieris brassicae</Emphasis>

This work investigated the ability of the gregarious larval endoparasitoid Cotesia glomerata L. (Hymenoptera: Braconidae) to adjust the progeny sex ratio and clutch size with repeated oviposition experience and the effect of a honey-based diet on the clutch size. In the field-collected clusters many clusters were female-biased but some clusters (3.8%) produced only male wasps, suggesting that there is a low percentage of unmated females in the field. Superparasitism was common in the field, and females were believed to increase progeny sex ratio when attacking previously parasitized hosts. In the laboratory, the number of eggs laid in a day tended to decrease with increasing female age. For females that were offered two hosts per day and for those offered three hosts per day, this value became nearly the same at 9 days after the start of oviposition. Old females which attacked many hosts tended to lay fewer eggs in a day than young ones. However, the degree of this tendency was not the same for all the parasitoid females of all three groups because sperm remained viable throughout a female’s lifetime. The amount of sperm used in a single oviposition bout seemed fixed and was not dependent on the number of eggs laid. Over the 2 days of the clutch size response experiment, the number of hosts a female attacked per day was not affected by the presence or absence of honey.     

两种赤眼蜂对捕食性天敌昆虫卵选择性观察

在室内采用非选择性和选择性方法，研究了松毛虫赤眼蜂和螟黄赤眼蜂对5种捕食性天敌昆虫卵的选择性。结果表明，两种赤眼蜂均可寄生日本通草蛉和大草蛉卵，并成功在卵内完成发育；但均不寄生龟纹瓢虫、异色瓢虫和七星瓢虫卵。同时面临防治靶标和草蛉卵时，两种赤眼蜂均选择寄生草蛉卵，但嗜好程度存在明显差异。松毛虫赤眼蜂对日本通草蛉卵的接触次数和寄生粒数比对亚洲玉米螟卵的显著要多；螟黄赤眼蜂对日本通草蛉卯的接触次数和寄生粒数比对棉铃虫卵的要多，但未达显著水平。在子代性比、每寄主出蜂数和寄生雌蜂率几项指标上，两种赤眼蜂在各自靶标和日本通草蛉之间均差异不显著。     

Oviposition behavior and development of immature stages ofParasierola swirskiana, a parasitoid of the lesser date mothBatrachedra amydraula

Parasierola swirskiana Argaman (Hymenoptera: Bethylidae) is a parasitoid of the mothBatrachedra amydraula Meyrick, a pest of unripe fruits of the date palm,Phoenix dactylifera L. The parasitoid is most commonly found in the field on second-generation host ,larvae. Its biological characteristics were studied in the laboratory. Adult longevity averaged 34.9 and 20.5 days for females and males, respectively. Clutch size ranged between 1 and 13 eggs per host, and was positively correlated with host weight. Females laid an average of 60.4 eggs on 11.6 hosts, with a maximum of 152 eggs on 29 hosts in 53 days. Parasitoids were observed standing motionless upon 52% of the paralyzed hosts, and active brood defense was occasionally observed. Immature development is described. Total development time from egg to adult averaged 13.6 days at 26 ± 2°C and 30-50% r.h. The potential for utilizingP. swirskiana for biological control ofB. amydraula is discussed.     

蜡螟绒茧蜂对大蜡螟幼虫的寄生作用

以大蜡螟的低龄幼虫为寄主,在实验室条件下对蜡螟绒茧蜂的寄生作用进行了研究。结果表明：蜡螟绒茧蜂一生最多产卵68粒,平均45.85粒。蜡螟绒茧蜂卵产于寄主体内的位置多在1～4腹节;多数在寄主体内只产1粒或2粒卵。该蜂能寄生大蜡螟1～4龄幼虫,但2～4龄幼虫同时存在时,偏爱寄生2、3龄幼虫,其选择系数分别为0.35和0.42。     

草地贪夜蛾对小麦和玉米的产卵选择性及其种群生命表

为明确草地贪夜蛾对小麦的产卵选择性及其是否对小麦安全生产构成威胁,本研究以玉米和小麦作为测试寄主,比较分析了草地贪夜蛾对两种作物不同部位的产卵选择性,并利用两性生命表方法研究了取食小麦、玉米对其生命参数的影响。结果表明:草地贪夜蛾更喜欢在玉米上产卵,其在玉米、小麦叶片、玉米和小麦茎秆上的产卵量存在显著差异(df=102,F=15.593,P<0.05),以玉米叶片背面卵块数量(7.11±1.55)块/笼最高;草地贪夜蛾取食小麦可以完成生活史,但幼虫存活率、化蛹率、羽化率和世代存活率低于取食玉米。取食玉米的幼虫发育历期为(16.31±0.15)d,显著高于取食小麦的(14.66±0.12)d,蛹期、蛹重、产卵前期、成虫寿命和世代周期无显著差异。取食小麦羽化出的雌虫寿命、平均单雌产卵量显著高于取食玉米,分别为(16.39±0.40)d、(976.31±57.21)粒和(14.64±0.32)d、(831.57±30.55)粒。生命表参数显示取食玉米的净增殖率为363.14,显著高于小麦的258.63,但内禀增长率、周限增长率和平均世代周期无显著差异。研究结果为草地贪夜蛾在小麦上的预测预报和有效防控提供了基础数据。     

Acquired resistance of pigeons to Argas polonicus larvae

The acquired resistance of pigeons to Argas polonicus manifests itself in an adverse effect on the feeding and further development of larvae. After five subsequent infestations, the rejection of larvae reached 90-95% and the mean weight of fed larvae dropped down from 2.18 mg to 1.72 mg in the Polish tick population. There appeared also a tendency to more rapid feeding in larvae from later infestations. Also the percentage of moulted larvae decreased, probably as a result of insufficient blood meal taken by larvae on repeatedly challenged hosts. The hosts sensitized by larvae of Polish tick population manifested a higher tick resistance than those sensitized by larvae of Czechoslovak population. No adverse effect has been observed in males and females after repeated infestation of sensitized pigeons. Anti-tick antibodies were detected in the serum of pigeons sensitized by larvae with the aid of counter current immunoelectrophoresis using extracts from whole larvae and from salivary glands of adults as antigen. No antibodies were detected in the serum of pigeons sensitized by adult ticks.     

利用斜纹夜蛾规模化繁育夜蛾黑卵蜂的初步研究

夜蛾黑卵蜂Telenomus remus Nixon是夜蛾科害虫的重要卵期寄生性天敌,可用于草地贪夜蛾Spodoptera frugiperda的生物防治.为了提高夜蛾黑卵蜂规模化繁育的生产效率,本文研究了利用斜纹夜蛾S.litora繁育夜蛾黑卵蜂时寄主卵龄、寄主产卵时间和蜂卵比对夜蛾黑卵蜂寄生率和羽化率的影响.结果表...     

Resource assessment and clutch size in the bean weevil,Acanthoscelides obtectus

Bean weevil (Acanthoscelides obtectus (Say)) females were found to use seeds (discrete resource patches) differentially when different sizes were offered in multiple-choice tests. Females, either as a group or as individuals, laid significantly (two to six times) more eggs on large seeds than on those of five times smaller mass. In contrast, seed shape (flattened or spherical) did not contribute to clutch-size adjustment. Thus, A obtectus females seem to measure only relative seed size when a comparison is possible. Nevertheless, females overload seeds with eggs and this can result in larval competition, so that, whereas resource size assessment and a robust egg-load adjustment indicate a trade-off between resource use and female fitness, it does not seem to provide much benefit for the progeny in stored dry beans. Several features, eg the use of oviposition markers and its consequences, may counterbalance the possible negative effects. It is assumed that, due to life cycle differences, females in the bean field may realise different fitness gains in comparison with those living in stores.     

乌鲁木齐地区甘蓝蚜发生规律初报

甘蓝蚜[Brevicoryne brassicae (Linné)]是烏魯木齐地区十字花科蔬菜上最主要的蚜虫。从9月下旬开始,在晚甘藍、晚苤藍及大白菜等蔬菜靠近地面的根、茎凹陷处,以及叶柄基部和叶片上产卵。蚜卵既可随寄主在菜窖里越冬;也可在菜株残体上露地越冬。露地越冬蚜卵,一般不能成为早春的有效蚜源,因其孵化率极低;孵化出来的少数干母,由于不能及时得到食料或因气候不适合,难以存活。越冬蚜卵于4月下旬孵化,5月中旬末产生有翅蚜,主要先在越冬寄生及冬蘿卜留种株上繁殖;到5月下旬至6月初,才陆續迁飞到春、夏十字花科蔬菜及春油菜上,大量繁殖和为害。7月下旬至8月初,晚甘藍与晚苤藍上的蚜虫便成为大白菜和冬蘿卜苗期的主要蚜源。甘藍蚜在烏魯木齐地区,无論是在菜窖里,或是在露地残株上,均不能以成蚜越冬。     

我国寄生蜂调控寄主生理的研究进展

寄生蜂是一类重要寄生性天敌昆虫,在害虫生物防治中发挥着重要作用。它们产卵时把自身携带的多种寄生因子(毒液、多DNA病毒等)注入寄主体内,由此调控寄主生长发育、免疫功能、营养代谢等以保证其后代在寄主体内或体上的成功发育。自20世纪80年代以来国内外昆虫学家对多种寄生蜂及其寄主构成的体系开展了寄生蜂调控寄主生理作用及其相关机制的研究,本文主要对我国昆虫学者的相关研究工作进行了总结和整理。     

In vitro culture of Bovicola limbata Gervais, 1844 (Mallophaga), study of its survival and life cycle

Bovicola limbata Gervais, 1844 has been cultured in vitro at 35 +/- 1.5 degrees and 75 +/- 5% R.H. using scrapings from goatskin and host hair as food. In these conditions its complete life cycle has been obtained. New data are given on the biology of this species: maximum, minimum and average number of eggs laid per female; reabsorbed, embryonal, hatched and unhatched eggs; percentage of specimens that reached the second, third and adult instars; mortality percentage in the first, second and third instars.     

The biology of nematodes of the family Capillariidae Neveu-Lemaire, 1936

The present knowledge of the life cycles of nematodes of the family Capillariidae is reviewed and these data are considered from the viewpoint of a new system of the classification of genera in this family (Moravec 1982). An analysis of the relevant literature as also own studies have shown that, in this nematode group, there occur both direct (homoxenous) life cycles without an intermediate host (Baruscapillaria, Pseudocapillaria, Calodium, Pseudocapillaroides, partly also Capillaria, Eucoleus and Aonchotheca) and heteroxenous cycles with participation of obligate intermediate hosts that are usually oligochaetes and rarely fishes (Schulmanela, Pearsonema, partly also Capillaria, Eucoleus and Aonchotheca). A remarkable case is the species Aonchotheca philippinensis, an intestinal parasite of man, with alternative life cycles, i.e. either with participation of the intermediate host or without it (autoinfection), this being dependent on whether eggs or larvae are produced by the female parasites. The transmission of some capillariid species with a direct life cycle may include paratenic hosts (oligochaetes, fishes). Capillariids undergo four moults during their ontogenetic development, the first of which taking place inside the body of the intermediate host in case of heteroxenous cycles. The present knowledge of the biology of nematodes of the Capillariidae is very incomplete; their life cycles have hitherto been studied (in a different extent) in members of only 9 out of 22 presently valid genera (approximately in 7% of recognized capillariid species).     

双斑截尾寄蝇对草地螟寄生的主要生物学特征及饲养技术

首次报道了双斑截尾寄蝇(Nemorilla maculosa Meigen)对草地螟(Loxostege sticticalis L.)的寄生行为及发育特征和饲养技术。研究结果表明:双斑截尾寄蝇将卵产在5龄草地螟幼虫的胸部,蝇蛆孵化后直接钻入寄主体腔内发育,幼虫发育成熟后便会钻出寄主体外化蛹。完成卵到幼虫期的发育需约12 d。蛹经11 d左右即可以羽化为成虫。从卵到成虫的发育历期约25 d。雌雄之间卵和幼虫的发育历期没有显著差异,但雌蛹的发育比雄蛹慢。雌蝇羽化后可以立即交配,而雄蝇羽化后约2 d后才能交配。补充营养的雌蝇平均产卵量约为130粒/头。还初步研究了影响双斑截尾寄蝇寄生能力的因素。简单介绍了其室内饲养繁殖技术。