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L-arginine, the substrate of nitric oxide synthase,inhibits fertility of male rats

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Asian Journal of Andrology 2001年第2期3卷 97-103页

作者： W.D.Ratnasooriya M.G.Dharmasiri Department of zoology University of Colombo Colombo 3 Sri LankaDepartment of Zoology University of Colombo Colombo 3 Sri Lanka

Aim: To examine the effect of L-arginine, the substrate of nitric oxide (NO) synthase, on reproductive function ofmale rats. Methods: Male rats were gavaged with either L-arginine (100 or 200 mg·kg^(-1)·d^(-1)), D-arginine (200mg·kg^(-1)·d^(-1)) or vehicle (0.9% NaCl) for seven consecutive days. Their sexual behaviour and fertility were evaluat-ed using receptive females. Results: L-arginine (200 mg/kg) had no significant effect on sexual competence (interms of sexual arousal, libido, sexual vigour and sexual performance). In mating experiments, the higher dose of L-arginine effectively and reversibly inhibited fertility, whilst the lower dose and the inactive stereoisomer D-arginine hadno significant effect. The antifertility effect caused by L-arginine was due to a profound elevation in the preimplantationloss mediated possibly by impairment in epididymal sperm maturation, hyperactivated sperm motility and sperm capaci-tation. Conclusion: Elevated NO production may be detrimental to male fertility.

关键词： L-arginine nitric oxide fertility libido sex behavior pre-implantation loss sperm motility contraceptives

Effects of Terminalia catappa seeds on sexual behaviour and fertility of male rats

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Asian Journal of Andrology 2000年第3期2卷 213-219页

作者： W.D.Ratnasooriya M.G.Dharmasiri Department of zoology University of Colombo Colombo 3 Sri LankaDepartment of Zoology University of Colombo Colombo 3 Sri Lanka

Aim: To evaluate the aphrodisiac potential of Terminalia catappa Linn. seeds using a suspension of its kernel (SS)in 1% methyl cellulose in rats. Methods: Male rots were orally treated with 1500 mg/kg or 3000 mg/kg SS or ve-hicle, and their sexual behaviour was monitored 3 h later using a receptive female. Another group of rats was orallytreated with either 3000 mg/kg SS or vehicle for 7 consecutive days. Their sexual behaviour and fertility were evaluatedon days 1, 4 and 7 of treatment and day 7 post-treatment by pairing overnight with a pro-oestrous female. Results:The 1500 mg/kg dose, had a marked aphrodisiac action (prolongation of ejaculation latency) but no effect on libido(% mounting, % intromission and % ejaculation), sexual vigour (mounting-and-intromission frequency), or sexualperformance (intercopulatory interval). In contrast, the higher dose (3000 mg/kg) reversibly inhibited all the para?e-ten of sexual behaviour other than mounting-and-intromission frequency and copulatory efficiency. The effects of highdose SS were not due to general toxicity, liver toxicity, haemotoxicity, stress, muscle deficiency, muscle incoordina-fion, analgesia, hypoglycaemia or reduction in blood testosterone level. They were due to marked sedation. Conclu-sion: The kernel of T. catappa seeds has aphrodisiac activity and may be useful in the treatment of certain forms ofsexual inadequacies, such as premature ejaculation.

关键词： Terminalia catappa seeds aphrodisiac male sexual behaviour libido premature ejaculation fertility sedation

Conserving the zoological resources of Bangladesh under a changing climate

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Integrative zoology 2009年第2期4卷 213-219页

作者： Bidhan C.DAS Department of zoology University of RajshahiRajshahiBangladesh

It is now well recognized that Bangladesh is one of the world’s most vulnerable countries to climate change and sea level *** levels of natural resources and a high occurrence of natural disasters further add to the challenges faced by the *** impacts of climate change are anticipated to exacerbate these existing stresses and constitute a serious impediment to poverty reduction and economic *** and biodiversity are important key sectors of the economy and natural resources of the country are selected as the most vulnerable to climate *** is for these reasons that Bangladesh should prepare to conserve its natural resources under changed climatic ***,the development of specific strategies and policies to address the effects of climate change on the ecosystem and on biodiversity has not commenced in ***,I present a detailed review of animal resources of Bangladesh,an outline of the major areas in zoological research to be integrated to adapt to climate change,and identified few components for each of the aforesaid areas in relation to the natural resource conservation and management in the country.

关键词： Bangladesh climate change conservation integrative approach.

Immunogenicity and efficacy of recombinant 78 kDa antigen of Leishmania donovani formulated in various adjuvants against murine visceral leishmaniasis

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Asian Pacific Journal of Tropical Medicine 2015年第7期8卷 511-517页

作者： Rajeev Nagill Tejinder Kaur Jyoti Joshi Sukhbir Kaur Department of zoology Panjab University

Objective: To analyze the protective efficacy of recombinant 78 kDa antigen of Leishmania donovani in combination with two adjuvants, that is, cationic liposomes or MPL-A against visceral leishmaniasis in BALB/c mice. Methods: The genomic DNA of promastigotes was isolated and 583 bp of T cell epitopes of gene encoding 78 k Da was amplified using specific primers. The amplified gene was cloned into p ET28 c, transformed into Escherichia coli BL21(DE3) and got expressed after IPTG induction. The recombinant protein was then purified using Ni-NTA and named r78. Three groups of mice were immunized with 10 μg of r78 plus MPL-A, r78 encapsulated in positively charged liposomes and control animals immunized with PBS. Two booster doses were given with the respective vaccine at an interval of 2 weeks each. Mice were challenged with 1×107 Leishmania promastigotes and sacrificed on different post infection/challenge days. Results: Immunization with r78 along with MPL-A and liposomeencapsulated r78 brought a significant reduction in parasite load. In comparison to the infected controls, the parasite load declined by 96.2% in mice immunized with r78 plus MPL-A and 97.23% in animals immunized with liposome-encapsulated r78. The immunized animals also exhibited profound DTH response. The serum antibody responses increased from 15 to 90 days post infection/challenge. Immunized animals showed greater IgG2 a levels and lesser Ig G1 levels in comparison to the infected controls. The splenocytes from immunized mice were cultured, stimulated with r78 and analyzed for cytokine profile. The levels of IL-2 and IFN-γ were greater in immunized animals as compared to control mice. Conclusions: The study proves that r78 in combination with suitable adjuvants is a potential vaccine candidate and may be instrumental in control of visceral leishmaniasis.

关键词： Visceral leishmaniasis r78kDa Liposomes MPL-A T cell epitope

Population dynamics of Piscicola geometra (Hirudinea: Rhynchobdellida) on Oreochromis Niloticus (Cichlidae) cultured in a rainforest fish pond, South Eastern Nigeria

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Journal of Environmental Sciences 2002年第4期14卷 536-540页

作者： Opara, K. N. (Department of zoology, University of Uyo, Nigeria. Department of zoology University of Uyo 尼日利亚

The distribution, abundance and intensity of the annelid worm, Piscicola geometra (leeches) infecting Oreochromis niloticus cultured in a rainforest fish pond, South Eastern Nigeria was studied over a 12 months period. Three hundred fish were examined of which 48.3% were infected. Infection occurred throughout the year, with a peak in February. Female fish had a significantly higher intensity of infection( P < 0.05) than males. There was a clear seasonal periodicity in the degree of infection and the distribution of the parasite exhibited an aggregated or contagious model of dispersion. There was a significant positive correlation between the size of the fish and worm burden.

关键词： Piscicola geometra pond Oreochromis niloticus population dynamics parasites

Parasites of the Nile rat in rural and urban regions of Sudan

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Integrative zoology 2009年第2期4卷 179-187页

作者： Dina M.FAGIR El-Amin EL-RAYAH Department of zoology University of KhartoumKhartoumSudan

In this investigation on endoparasites(helminths)and ectoparasites of the Nile rat(Arvicanthis niloticus Desmarest,1822),a total of 220 Nile rats were trapped from different regions of Sudan during the period January 2003–January *** of different tissues,identification of parasites,effect of these parasites on the organs,the preva-lence and intensity of infestation of the parasites and their relation to the habitat of the host,and sex-related infestations were *** showed that the variation among helminth species was wide,especially in those that are transferred by *** protozoan parasites or distortion in the infected tissues were *** examination for Toxoplasma gondii was carried *** species of cestodes(Hymenolepis nana,Hymenolepis diminuta),two genera(Raillietina sp.I,Raillietina ***)and one unidentified Hymenolepididae were *** most prevalent species of cestodes was Raillietina *** for nematodes only one species and one genus were recovered(Monanema nilotica and Streptopharagus sp.).Investigation of skin revealed that 83.8%of rats were infested with one or more of ectoparasites;namely,insects and *** survey also revealed that fleas and lice were the most common ectoparasites that infested the Nile *** rodents,particularly those living in close association with man,play a significant role in human health,welfare and *** has to be stressed that their arthropod ectoparasites are important vectors of pathogenic microorganisms and they can also be important reservoirs for parasitic zoonoses,like trichinellosis and *** doubt,the increase in rodent populations could be followed by an increase in zoonotic diseases(Stojcevic et al.2004,Durden et al.2000).Rats and mice(commensal and wild)play an important role in public health,being carriers or reservoirs for infectious diseases that can be transmitted to humans(zoonoses).Xenopsylla cheopis is the most important vector

关键词： Arvicanthis fleas lice mites Nile rat Sudan ticks.

Biological consequences of global change: opportunities and challenges

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Integrative zoology 2012年第2期7卷 111-112页

作者： Zhibin Zhang Editor-in-Chief Integrative Zoology Institute of ZoologyChinese Academy of Sciences BeijingChina

Global change has become a major ***life habitat loss,environmental pollution,biological invasion and transmission of infectious diseases are some of the negative effects of intensified human disturbance(Ceballos&Ehrlich 2002).There has been fierce debate concerning the cause of climate *** most popular view is that recent warming has been caused largely by an increase in CO_(2),due to rapid development of industry ***,some insist that global warming is a natural variation in the temperature of the *** any case,the long-term effects of climate warming remain unclear.

关键词： consequences intensified warming

Mosquito autogeny in Aedes caspius （Diptera： Culicidae）： alterations of larval nourishments reservation upon bacterial infection

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Insect Science 2013年第4期20卷 472-484页

作者： Ashraf M. Ahmed zoology Department College of Science King Saud University SaudiArabia zoology Department College of Science Minia UniversityEl-Minia Egypt

The present study recorded mosquito autogeny for the first time amongst Aedes caspius species in the Eastern region of Saudi Arabia. Laboratory rearing showed an obligatory autogenous species of Ae. caspius since it foregoes blood feeding during its first ovarian cycle, even in the presence of the hosts （CD mouse）, but produces its second egg batch only if ingested a blood meal. Both morphological and molecular identification confirmed that both autogenous and anautogenous strains belong to the same species of Ae. caspius. Data from biochemical analysis showed significant 2, 1.6, and 1.4 folds higher total carbohydrates, proteins, and lipids reserves respectively in the fourth larval instar of the autogenous strain compared to that of the anautogenous ones. In addition, exposing the fourth larval instars of autogenous strain to the infection stress by the mosquito larvicidal bacterium, Bacillus thuringiensis var kurstaki has significantly reduced total carbohydrates, proteins and lipids reserves by 29%, 35%, and 46%, respectively, at 12 h postinfection compared to those of uninfected ones. These reductions in nourishment reserves were more pronounced at 24 h postinfection in the case of proteins and lipids, but not carbohydrates. These results may indicate that bacterial infection is a health stress that significantly reduced nourishments reservation, which may interrupt the success of adult autogeny. However, the impact of infection-induced decline in larval nourishments reservation on successful adult autogeny is still to be investigated.

关键词： Aedes caspius anautogeny autogeny Bacillus thuringiensis nourishmentsreservation

Copulatory pattern and behavior in a semi-captive population of Eld＇s deer

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Current zoology 2011年第3期57卷 284-292页

作者： Zhigao ZENG Yan-Ling SONG Qiong ZHANG Institute of zoology Chinese Academy of Sciences Beijing 100101 China

Male copulatory patterns, female multiple copulation and male post-copulatory guarding were studied in Eld＇s deer Cervus eldi in Datian National Nature Reserve, China. Mating behavior in 18 females and 11 males from a group of 61 semi-captive Eld＇s deer were observed. The majority （55.8%） of copulations occurred between 15：00-19：00 h. The ejaculatory mount was preceded by an average of 5.1 prior mounts. Successful copulation consisted of a single thrust with ejaculation during one intromission, with no lock. This copulatory pattern is classified as pattern No. 15 （no lock, no intravaginal thrusting, single intromission, and multiple ejaculation） and No. 16 （no lock, no intravaginal thrusting, single intromission, and single ejaculation） under Dewsbury＇s scheme （1972） and as No. 16 （no lock, no thrusting, single and brief intromission） under Dixson＇s classification （1998）. Copulation frequency was 1.5 ± 0.9 times for males/females with the same female/male per day. The duration of the final mount, which included ejaculation, was brief （3.4±1.3 s）, and ejaculation usually terminated copulation. Eleven females copulated more than once in this study： three of them copulated with several males （multi-male copulations） and the remainder copulated with a single male （repeated copulations）. Our results indicate that some female Eld＇s deer may seek multiple copulations to be a strategy to improve the genetic quality of their offspring or to avoid harassment. Post-copulatory guarding of females by males followed all copulations, with dominant males guarding for significantly longer than subordinate males. Dominant males appear to be more effective at post-copulatory guarding than subordinate males. Subordinate males engaged in a quicker pre-copulatory phase to improve their chances of finishing copulation before being forced to accede to dominant males [Current zoology 57 （3）： 284-292, 2011].

关键词： Cervus eldi Copulatory pattern Female multiple copulation Post-copulatory guarding Dominant male Subordinate male