A bibliography on ticks and tick‐borne diseases in the countries of the Benelux (1567–1978)

Summary

Information published between 1567 and 1978 on this subject contains at least 223 titles. They cover medical and veterinary as well as biological aspects. Full bibliographical details of the publications are given. A subject index (to tick species, host species, and diseases transmitted) increases the availability of the data included. Some of the more interesting results of the study are discussed in a short introduction.     

Notes on the occurrence of tubercular spines in Schistosoma margrebowiei and Schistosoma mattheei

Scanning electron microscopical (SEM) studies on the tegument of the bovid schistosomes, Schistosoma margrebowiei and Schistosoma mattheei have yielded conflicting results; certain authors observed the tubercles on the tegument of these species to be spined, while others reported that they are spineless. The present study indicates that the protrusion of tubercular spines is subject to phenotypic plasticity regulated by external factors such as the identity of the host species and whether or not the schistosome is paired.     

Climate change and the genus Rhipicephalus (Acari: Ixodidae) in Africa

The suitability of present and future climates for 30 Rhipicephalus species in Africa are predicted using a simple climate envelope model as well as a Division of Atmospheric Research Limited-Area Model (DARLAM). DARLAM's predictions are compared with the mean outcome from two global circulation models. East Africa and South Africa are considered the most vulnerable regions on the continent to climate-induced changes in tick distributions and tick-borne diseases. More than 50% of the species examined show potential range expansion and more than 70% of this range expansion is found in economically important tick species. More than 20% of the species experienced range shifts of between 50 and 100%. There is also an increase in tick species richness in the south-western regions of the sub-continent. Actual range alterations due to climate change may be even greater since factors like land degradation and human population increase have not been included in this modelling process. However, these predictions are also subject to the effect that climate change may have on the hosts of the ticks, particularly those that favour a restricted range of hosts. Where possible, the anticipated biological implications of the predicted changes are explored.     

分子标记基因在动物寄生螨类基因差异研究中的应用

关于寄生在不同宿主体上的同一种螨属于同一个种的不同亚种还是不同的种的问题，学者们至今还未达成一致观点。传统的动物寄生螨虫分类主要依据形态学和宿主的特异性进行，随着现代分子生物学技术的发展，分子标记技术被广泛应用于动物寄生螨虫的分类。     

河西走廊盐化草甸土壤水盐对植物群落数量特征的影响

采用通径及逐步回归方法分析了从河西走廊盐化草甸４３个样点收集的植物与土壤水盐资料。土壤水盐因子（包括土壤水分、盐分及与之显著相关的有机质、ｐＨ及地下水位）对群落及其优势种（芦苇与＊草）的数量特征均有显著影响，群落盖度主要取决于土壤盐分与有机质；芦苇与赖草盖度分别取决于土壤盐分与有机质，高度分别取决于地下水位及土壤水分；赖草频度及生物量与土壤ｐＨ有关。盖度与高度是受土壤水盐因子影响较大的两个群落特征，可作为群落优势度的构成要素。芦苇与赖草的群落特征受制于不同的土壤水盐生态因子，显示了二种土壤水盐生态位的分异，这可能是二种长期共存的生态学机制。     

A new blood parasite within the relict endemic New Zealand gecko Hoplodactylus duvaucelii

Duvaucel geckos (Hoplodactylus duvaucelii) are large endemic lizards that have been extirpated from the New Zealand mainland due to introduced mammalian predators. This species has subsequently become the subject of species translocation conservation management in an endeavour to increase the number of populations and as a part of island ecological restoration. Blood sampling of a captive adult male after tail autotomy led to the discovery of a Rickettsia-like organism within this gecko's erythrocytes. We conclude that this infection was acquired at the gecko's source location, a remote island closed to the general public and lacking potential invasive parasite reservoir reptiles. The likely vector is the native mite Geckobia naultina. This finding represents valuable new baseline information about the health parameters of this threatened species. Particularly in the light of the paucity of reported blood parasitism in New Zealand reptiles, the conservation management of this species through relocation and captive-breeding, and the on-going concerns regarding the introduction of novel parasites to New Zealand.     

A survey of some drugs commonly used in the camel

Specific recommendations for drug dosages for the camel are rare and doses for this species are usually extrapolated from those recommended for other species. The pharmacology and toxicity of drugs likely to be used in the camel needs to be further studied to ensure the efficacy and safety of these drugs in this species.Most of the reported work is on the chemotherapeutic efficacy of a few drugs long in use in other species against trypanosomiasis, mange and gastrointestinal nematodes. Areas of study most deficient are pharmacodynamics, pharmacokinetics and drug metabolism. The anatomical, physiological and biochemical peculiarities of the camel warrant more pharmacological and toxicological studies in this species.This article surveys the literature on the pharmacology, toxicity and therapeutic uses of some antiparasitic and antibacterial drugs and central nervous system depressants commonly used in the camel. It appears that camels are more susceptible to the toxic action of some trypanocidal drugs than other species. In certain cases they may metabolize some drugs differently. In general, the camel appears to be a good subject for analgesics and anaesthetics.     

人工草地群落稳定性及其调控机制研究现状

人工草地的群落稳定性是草地生态学的主要研究内容之一。它是指在种间竞争、环境压力和干扰活动三个因子存在的条件下 ,人工植物群落各组分稳定共存、草地生产能力和经济利用价值不致降低的状态。人工草地群落稳定性的合理调控是维护高效、持久的人工草地 ,提高人工草地生产力的有效途径。其调控机制主要有牧草组分种间竞争 (品种组合 )、环境压力 (水、肥条件 )和干扰活动 (放牧和刈割 )等三种方式。分析人工草地群落稳定性及其调控机制研究现状 ,北美和西欧一些国家已在此研究领域内取得了较大进展 ,研究技术和理论体系在不断更新和完善 ;相对而言 ,我国尚处于起步阶段 ,研究工作开展得较少 ,技术手段较为落后 ,理论水平较低。今后我国草地学界应将群落稳定性及其调控机制列为专项课题 ,进行深入、细致的探索研究。     

A revision of the genus Impalaia M?nnig, 1924

A revision of the genus Impalaia M?nnig, 1924 forms the subject of this report. Besides the type species, Impalaia tuberculata M?nnig, 1924, there are 2 valid species, viz., I. nudicollis M?nnig, 1931 and I. okapiae (Van den Berghe, 1937). I. tuberculata longispiculata (Wetzel & Fortmeyer, 1960), I. somaliensis (Crovieri, 1929) and I. aegyptiaca Soliman, 1956 are synonymous with I. tuberculata. I. taurotragi (Le Roux, 1936) appears to be an aberrant form of I. nudicollis. A parasite/host checklist is included.     

Water balance in the dog and cat

In respect of its metabolic control of water balance, the cat probably differs as much from the dog as it does in most other respects. In qualitative terms the routes of gain and loss of water are very much the same: in quantitative terms and in its homeostatic response to different environmental stimuli or insults the cat and the dog are rather different. Dogs and cats are among the commonest species with which veterinarians have to deal. They share much the same environment and are treated in much the same way by their owners. They are almost interchangeable as pets. So far as the veterinary profession is concerned, there are a few outstanding differences such as their response to certain drugs, their reproductive behaviour and their range of aggressive and defensive weapons—but they are in other ways treated in a somewhat similar fashion. It is, however, only within recent years that some other outstanding differences have really become identified between the two species. These differences are in aspects of protein, fat and vitamin metabolism which have direct or indirect relevance to feeding cats and dogs. But they are also manifest in water metabolism, which is the subject of this paper. The first part of this paper will deal with some differences in the water metabolism of dogs and cats which are in the scientific literature but are not widely known outside the research field. The second part will describe some of the work which we have been doing on food/water interrelationships of the dog and cat.     

Close chromosomal congruence in two species of ground squirrel: Xerus inauris and X. princeps (Rodentia: Sciuridae)

Chromosomes from cultured fibroblasts of two southern African ground squirrel species, Xerus inauris (2n = 38) and X. princeps (2n = 38), were compared using G-banding, C-banding and silver nitrate staining for the detection of NORs (nucleolar organizer regions). The karyoptypes of the two species, whose taxonomic status is the subject of some uncertainty, are largely identical except for a subtle heterochromatic difference which affects a single autosomal chromosome pair in X. inauris. The species specificity of this marker in their zone of contact indicates an absence of gene flow between these taxa and gives credence to the recognition of X. inauris and X. princeps as two biologically distinct species.     

Artificial insemination in the dog

Extract

Little could the Abbe Spallanzani have known the extent to which artificial insemination would develop when in 1780 he successfully inseminated a bitch with semen siphoned from the vagina of a second bitch. Three live puppies were reported to have been born to this insemination after a 62-day gestation. A long period elapsed before the possibilities of this technique were refined to their present state and it is only during this century that the full potential of the method as a means of animal breeding is being realized. Although the initial success utilized the dog as the experimental subject developments have been more restricted in this than in other common domestic species and critical research reports are still relatively few. It is the purpose of this paper to summarize progress achieved to date and to raise questions to which we still await unequivocal answers.     

Salinity ranges of some southern African fish species occurring in estuaries

The recorded salinity ranges of 96 fish species occurring in southern African estuaries are documented. Factors influencing the tolerance of fishes to low and high salinity regimes are discussed, with most species tolerant of low rather than high salinity conditions. This is important since most systems are subject to periodic freshwater flooding, especially during summer. The penetration of freshwater teleosts and elasmobranchs into estuaries is examined and the occurrence of marine fishes in rivers documented. Mortalities arising from salinity extremes in southern African estuaries are discussed, with temperature a key factor initiating such fish kills. Only eight fish species have been recorded spawning in estuaries although the fry of many species are attracted to estuarine waters. It is concluded that a small percentage of southern African fishes have succeeded in utilizing estuaries and this may be attributed to the paucity of strong osmoregulators     

Regulation of the Estrous Cycle in Domestic Animals — A Review

Neuroendocrine and endocrine factors involved in the regulation of reproductive cycles in domestic animals are discussed. Although research data from many species are considered, emphasis is placed on their relevance for the cow, sow, ewe and, to a lesser extent, the mare. Literature cited is not designed to be complete, but rather to be representative of the large volume of material which has been written on the subject.

Gonadotropin-releasing hormone is synthesized and secreted in response to various exteroceptive stimuli, but both its release and its effects on the anterior pituitary are modified by feedback of target gland hormones. A modulating role for nonsteroidal regulators such as inhibin has yet to be proven. Prostaglandins are important for corpus luteum regression and ovulation.

The relative roles of the gonadotropins and the above substances in hypothalamic, adenohypophyseal and ovarian function are considered. General mention is made of mechanisms of hormonal action.

     

Prevalence of Bartonella species DNA and antibodies in cats (Felis catus) submitted to a spay/neuter program in Rio de Janeiro, Brazil

The prevalence of Bartonella species DNA and antibodies for Bartonella henselae were studied in 40 clinically healthy cats (Felis catus, Linnaeus 1758) submitted to a spay/neuter program in Rio de Janeiro, Brazil. Additionally, the prevalence of Bartonella species DNA was investigated in the fleas found parasitizing the subject cats. For this purpose, blood samples were obtained from all cats, and DNA extraction was performed on the blood, and blood clotted samples, as well as on pools of fleas obtained from them. Antibodies for B henselae were detected on serum samples. Bartonella species DNA was detected in 17 cats, whereas serum reactivity for B henselae was found in 19. A total of 20 cats were flea-infested and nine of these 20 had Bartonella species DNA in their blood. In four of the 20 flea-infested cats, Bartonella species DNA was detected in the fleas obtained from those cats, but only one of these four cats had Bartonella species DNA in its blood.     

Discrimination between individual humans by domestic fowl (Gallus gallus domesticus).

1. We demonstrate that Barred-Rock and Isa-Brown hens can discriminate between the presence of 2 different humans and use this information as a cue for whether or not to make an operant response. 2. This demonstration in domestic fowl, the first of its kind in any avian subject, is consistent with a growing body of evidence that many species, including agricultural animals, are surprisingly adept at differentiating between humans. 3. Such a discriminative ability carries considerable implications for issues related to husbandry, production and welfare.     

Chlamydial diseases of domestic animals--zoonotic potential of the agents and diagnostic issues

The role of chlamydiae as agents of a number of important animal and human diseases is still the subject of intensive research. Recently, a proposal for taxonomic reclassification of this group of obligate intracellular bacteria was published, which was based on a large amount of new data on genetic relatedness. According to this proposal, the family Chlamydiaceae now comprises two genera (Chlamydia and Chlamydophila) with 9 largely host-related species. The previously accepted classification scheme had distinguished 4 species within the genus Chlamydia. The most important animal chlamydiosis with zoonotic character is psittacosis, a systemic disease in psittacine birds of acute, protracted, chronic or subclinical manifestation. The analogous infection in domestic and wild fowl is known as ornithosis. Avian strains of C. psittaci (new classification: Chlamydophila psittaci) can also infect humans, the symptoms being mainly unspecific and influenza-like, but severe pneumonia, endocarditis and encephalitis are also known. The main group of persons facing an elevated risk of infection includes those having frequent contact with domestic and companion birds at work or in their spare time. In Germany, the annual average of notified cases is approximately 100. Cases of transmission to humans were repeatedly reported in connection with enzootic abortion in sheep (causative agent: C. psittaci or Chlamydophila abortus, respectively). Various chlamydial species occur as pathogens and commensals as well in cattle, pigs, horses, and cats. The assessment of the actual epidemiological importance is, however, often difficult because of their almost ubiquitous spread. Likewise, those strains of C. pneumoniae (new classification: Chlamydophila pneumoniae) found in several animal species can not yet be assessed for pathogenic properties. The possibilities for diagnostic detection of chlamydiae have considerably improved following the introduction of molecular methods, particularly the polymerase chain reaction (PCR), which permits direct identification from clinical specimens and differentiation of species.     

人工草地放牧系统优化模式研究 Ⅰ 人工草地的最大持续产量模型和最优控制方法及应用

文章以云贵高原的人工草地为研究对象，分析了草地资源分布的时空特征及增长动态，运用生物控制论方法组建了牧草资源种群保护性利用的最大持续产量模型，并以试验为例，确定了具体的保护指标与放牧管理措施，研究了单播人工草地的最优控制模型与放牧对策，进行了相应的定量分析。     

A physiological approach to research in pasture utilization

A study of species selection by cattle under a system of controlled selective grazing using wheel‐point surveys and fistulated animals has demonstrated that both techniques provide valuable information on the preference shown for such species as Andropogon amplectens, Eulalia villosa, Themeda triandra, Trachypogon spicatus, Tristachya hispida and Monocymbium ceresiiforme.

The wheel‐point survey, which presents information on the degree of utilization of different species over the entire grazing period, is complemented by the more detailed information obtained by identifying grass species from oesophageal fistula samples obtained at specific times within the grazing period.

Preference for species does not appear to be markedly affected by their relative contribution to basal cover, but apparently is subject to seasonal variations.