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Habitat fragmentation, vole population fluctuations, and the ROMPA hypothesis: An experimental test using model landscapes

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Integrative Zoology 2016年第6期11卷 469-482页

作者： George O.BATZLI Department of Animal Biology University of IllinoisChampaignIllinoisUSA

Increased habitat fragmentation leads to smaller size of habitat patches and to greater distance between patches.The ROMPA hypothesis(ratio of optimal to marginal patch area)uniquely links vole population fluctuations to the composition of the landscape.It states that as ROMPA decreases(fragmentation increases),vole population fluctuations will increase(including the tendency to display multi-annual cycles in abundance)because decreased proportions of optimal habitat result in greater population declines and longer recovery time after a harsh season.To date,only comparative observations in the field have supported the hypothesis.This paper reports the results of the first experimental test.I used prairie voles,Microtus ochrogaster,and mowed grassland to create model landscapes with 3 levels of ROMPA(high with 25%mowed,medium with 50%mowed and low with 75%mowed).As ROMPA decreased,distances between patches of favorable habitat(high cover)increased owing to a greater proportion of unfavorable(mowed)habitat.Results from the first year with intensive live trapping indicated that the preconditions for operation of the hypothesis existed(inversely density dependent emigration and,as ROMPA decreased,increased per capita mortality and decreased per capita movement between optimal patches).Nevertheless,contrary to the prediction of the hypothesis that populations in landscapes with high ROMPA should have the lowest variability,5 years of trapping indicated that variability was lowest with medium ROMPA.The design of field experiments may never be perfect,but these results indicate that the ROMPA hypothesis needs further rigorous testing.

关键词： experimental landscapes habitat fragmentation Microtus ochrogaster ROMPA hypothesis vole population fluctuations

Day length constrains the time budget of aphid predators

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Insect Science 2019年第1期26卷 164-170页

作者： Jens Joschinski Tim Kiess Jochen Krauss department of animal Ecology and Tropical biology BiocentreUniversity of WEirzburgWEtrzburgGermany

Phenology shifts and range expansions cause organisms to experience novel day length-temperature correlations.Depending on the temporal niche,organisms may benefit or suffer from changes in day length,thus potentially affecting phenological adaptation. We assessed the impact of day length changes on larvae of Chrysoperla carnea (Stephens) and Episyrphus balteatus (De Geer),both of which prey on aphids.Larvae ofE.balteatus are night-active,whereas those of C.carnea appear to be crepuscular.We subjected both species in climate chambers to day lengths of 16 :8 L :D and,to circumvent diapause responses,20 :4 L :D.We recorded development times and predation rates of both species. E.balteatus grew 13%faster in the 16 :8 L :D treatment and preyed on significantly more aphids.In contrast,C.carnea grew 13% faster in the 20 :4 L :D treatment and higher predation rates in 20 :4 L :D were marginally significant.Our results show that day length affects development and predation,but that the direction depends on species. Such differences in the use of day length may alter the efficiency ofbiocontrol agents in a changing climate.

关键词： Chiysoperla carnea climate change Episyrphus balteatus insect timing phenology photoperiod

Testing the potential mechanisms for the maintenance of a genetic color polymorphism in bluefin killifish populations

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Current Zoology 2018年第6期64卷 733-743页

作者： Ashley M.JOHNSON Chia-Hao CHANG Rebecca C.FULLER Department of Animal Biology School of Integrative BiologyUniversity of Illinois at Urbana-ChampaignChampaignIL 61820USA

The maintenance of genetic variation in the face of natural selection is a long-standing question in evolutionary biology.In the bluefin killifish Lucania goodei,male coloration is polymorphic.Males can produce either red or yellow coloration in their anal fins,and both color morphs are present in all springs.These 2 morphs are heritable and how they are maintained in nature is unknown.Here, we tested 2 mechanisms for the maintenance of the red/yellow color morphs.Negative frequency-dependent mating success predicts that rare males have a mating advantage over common males. Spatial variation in fitness predicts that different color morphs have an advantage in different microhabitat types.Using a breeding experiment,we tested these hypotheses by creating populations with different ratios of red to yellow males (5 red:1 yellow;1 red:5 yellow)and determining male mating success on shallow and deep spawning substrates.We found no evidence of negative frequency-dependent mating success.Common morphs tended to have higher mating success, and this was particularly so on shallow spawning substrates.However,on deep substrates,red males enjoyed higher mating success than yellow males,particularly so when red males were rare. However,yellow males did not have an advantage at either depth nor when rare.We suggest that preference for red males is expressed in deeper water,possibly due to alterations in the lighting environment.Finally,male pigment levels were correlated with one another and predicted male mating success.Hence,pigmentation plays an important role in male mating success.

关键词： carotenoid color polymorphism environmental heterogeneity melanin negative frequency dependence pterin

Oxidized palm oil impairs reproductive functions and architectures in female rats

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Asian pacific Journal of Reproduction 2023年第4期12卷 182-193页

作者： Wankeu-Nya Modeste Kengne Inès T Ateba Benjamin S Bend Fortune E Djeumeni Ornela N HathoDominique T Ngadjui E Moundipa Paul F Massoma DieudonnéL Dongmo Alain B Watcho Pierre department of animal Organisms biology Faculty of ScienceUniversity of DoualaDoualaCameroon department of animal Production Faculty of Agronomy and Agricultural SciencesUniversity of DschangDschangCameroon department of Biochemistry Faculty of ScienceUniversity of YaoundéIYaoundéCameroon Department of Animal Biology Faculty of ScienceUniversity of DschangDschangCameroon

Objective:To evaluate the effects of three oxidized palm oil diets(OPD)on female rat reproductive function.Methods:Forty-four female Wistar rats presenting five consecutive and regular estrous cycles were divided into 4 groups.The rats were fed with:a standard diet,70%of standard diet+30%oxidized palm oil diet(OPD1),OPD1+5 g of boiled yolk egg(OPD2)and OPD1+10%sucrose(OPD3)for 125 days,respectively.During the feeding period,morphometric,estrous cycle,sexual behavior,gestation,biochemical and histomorphometric parameters were evaluated.Results:All OPDs significantly increased abdominal circumference,body mass index and Lee index coupled to an irregularity and lengthening of the estrous cycle.They significantly decreased appetite and consumption behaviours,quantic pregnancy index,fertility rate,implantation sites and index,serum progesterone and high-density lipoprotein levels,increased pre-implantation losses,anti-implantation activities,serum estradiol,triglycerides,total and low-density lipoprotein-cholesterol levels,and impaired brain and ovaries oxidative status.Histomorphometric examinations revealed increases in the number of atresic and primary follicles and decreases in secondary,tertiary,Degraaf,total and corpus luteum follicles in ovaries coupled to a neurodegeneration of hypothalamic anteroventral periventricular neurons in the OPD groups compared to the standard diet group.Conclusions:The three OPDs induce obesity and impair the female reproductive function,especially OPD2 and OPD3.These findings contribute to a better understanding of the adverse effects of palm oil bleaching on the reproductive function in female rats,which could be useful in the management of women with obesity-related sexual dysfunction.

关键词： Bleached palm oil Reproductive function Anteroventral periventricular nucleus Ovary Estrogen Progesterone Female rat

Conceptus elongation in ruminants: roles of progesterone, prostaglandin, interferon tau and cortisol

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Journal of animal Science and Biotechnology 2015年第2期6卷 151-162页

作者： Kelsey Brooks Greg Burns Thomas E Spencer department of animal Science and Center for Reproductive biology Washington State University

The majority of pregnancy loss in ruminants occurs during the first three weeks after conception, particularly during the period of conceptus elongation that occurs prior to pregnancy recognition and implantation. This review integrates established and new information on the biological role of ovarian progesterone （P4）, prostaglandins （PGs）, interferon tau （IFNT） and cortisol in endometrial function and conceptus elongation. Progesterone is secreted by the ovarian corpus luteum （CL） and is the unequivocal hormone of pregnancy. Prostaglandins （PGs） and cortisol are produced by both the epithelial cells of the endometrium and the trophectoderm of the elongating conceptus. In contrast, IFNT is produced solely by the conceptus trophectoderm and is the maternal recognition of pregnancy signa that inhibits production of luteolytic pulses of PGF2α by the endometrium to maintain the CL and thus production of P4. Available results in sheep support the idea that the individual, interactive, and coordinated actions of P4, PGs, IFNT and cortisol regulate conceptus elongation and implantation by controlling expression of genes in the endometrium and/or trophectoderm. An increased knowledge of conceptus-endometrial interactions during early pregnancy in ruminants is necessary to understand and elucidate the causes of infertility and recurrent early pregnancy loss and provide new strategies to improve fertility and thus reproductive efficiency.

关键词： Conceptus Cortisol Endometrium Interferon Prostaqlandin Ruminant

Laboratory rearing of solitary bees and wasps

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Insect Science 2016年第6期23卷 918-923页

作者： Mira C. Becker Alexander Keller department of animal Ecology and Tropical biology Biocenter University of Wurzburg Wurzburg Germany

Ecological experiments often require standardized methods that exclude natural variation and allow manipulation of a single parameter. It has been shown that domesticated honey bee larvae are raisable in a controlled environment. Here we demonstrate that this approach is also transferable to wild solitary bees and wasps without inducing negative effects on their development. Wells may also be supplemented with the antibiotic substance oxytetracycline to control the presence of bacteria. The method thus provides a useful tool to investigate offspring recruitment and larval development in solitary bees and wasps, plus their responses to manipulation of factors as for example diets, toxins and microbiota.

关键词： diet manipulation ecotoxicology larval ontogeny Osmia bicornis oxytetracycline pathogens

Myotropic activity and immunolocalization of selected neuropeptides of the burying beetle Nicrophorus vespilloides (Coleoptera: Silphidae)

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Insect Science 2019年第4期26卷 656-670页

作者： Arkadiusz Urbanski Jan Lubawy Pawel Marciniak Grzegorz Rosinski Faculty of biology Department of Animal Physiology and Development Adam Mickiewicz University in Poznan Poznan Poland

Burying beetles (Nicrophorus sp.) are necrophagous insects with developed parental care. Genome of Nicrophorus vespilloides has been recently sequenced, which makes them interesting model organism in behavioral ecology. However, we know very little about their physiology, including the functioning of their neuroendocrine system. In this study, one of the physiological activities of proctolin, myosuppressin (Nieve? MS), myoinhibitory peptide (Trica-MIP-5) and the short neuropeptide F (Nicve-sNPF) in N. vespilloides have been investigated. The tested neuropeptides were myoactive on N. vespilloides hindgut. After application of the proctolin increased hindgut contraction frequency was observed (EC50 value was 5.47 x 10-8 mol/L). The other tested neuropeptides led to inhibition of N. vespilloides hindgut contractions (Nicve-MS: IC50 = 5.20 x 10~5 mol/L;Trica-MIP-5: IC50 = 5.95 x 10-6 mol/L;Nicvc-sNPF: IC50 = 4.08 x 10-5 mol/L). Moreover, the tested neuropeptides were immunolocalized in the nervous system of N. vespilloides. Neurons containing sNPF and MIP in brain and ventral nerve cord (VNC) were identified. Proctolin-immunolabeled neurons only in VNC were observed. Moreover, MIP-immunolabeled varicosities and fibers in retrocerebral complex were observed. In addition, our results have been supplemented with alignments of amino acid sequences of these neuropeptides in beetle species. This alignment analysis clearly showed amino acid sequence similarities between neuropeptides. Moreover, this allowed to deduce amino acid sequence of N. vespilloides proctolin (RYLPTa), Nicve-MS (QDVDHVFLRFa) and six isoforms ofNicve-MIP (Nicve-MIP-1一 DWNRNLHSWa;Nicve-MIP-2—AWQNLQGGWa;Nicve-MIP-3—AWQNLQGGWa;Nicve-MlP-4—AWKNLNNAGWa;Nicve-MIP-5—SEWGNFRGSWa;Nicve-MIP-6— DPAWTNLKGIWa;and Nicve-sNPF—SGRSPSLRLRFa).

关键词： burying beetles immunolocalization myotropic activity neuropeptides nervous system

Reconciling concepts, theory, and empirical patterns surrounding cascade reinforcement

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Current Zoology 2016年第2期62卷 131-134页

作者： Rebecca C. FULLER Department of Animal Biology University of Illinois Urbana IL 61801 USA

An introduction is presented in which the editor discusses articles in the issue on topics including reproductive isolation (RI), natural selection and fish population.

关键词：调和加固梯级

Cyclophosphamide-induced reproductive toxicity: Beneficial effects of Helichrysum odoratissimum(Asteraceae) in male Wistar rats

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Journal of Integrative Medicine 2019年第5期17卷 366-373页

作者： Pierre Watcho Ismaelle Rosine Mpeck Patrick Brice Deeh Defo Modeste Wankeu-Nya Esther Ngadjui Georges Romeo Bonsou Fozin Pierre Kamtchouing Albert Kamanyi animal Physiology and Phytopharmacology Laboratory University of DschangP.O. BOX 67DschangCameroon department of animal Organisms biology University of DoualaP.O. BOX 24157DoualaCameroon Department of Animal Biology and Physiology University of YaoundeP.O. BOX 812YaoundeCameroon

Objective: Cyclophosphamide(CP) is commonly used to treat some cancers, but its clinical efficacy is also linked with testicular toxicity. We investigated the effects of aqueous extract(AE) and methanolic extract(ME) of Helichrysum odoratissimum for reducing CP-induced reproductive toxicity in male rats.Methods: In addition to a normal control(group 1), drugs or vehicles were administered orally to seven groups(n = 5) of rats that had already received 4-weeks of pre-treatment with CP(5 mg/[kgád], per oral administration);group 2 received CP + distilled water(10 m L/[kgád]);group 3 received CP + 5% tween 80(10 m L/[kgád]);group 4 received CP + clomiphene citrate(0.25 mg/[kgád]);groups 5 and 6 received CP + AE(50 and 100 mg/[kgád]) and groups 7 and 8 received CP + ME(50 and 100 mg/[kgád]). animals were sacrificed on day 15, and body and sexual organ weights, sperm characteristics, testosterone level and testicular histology were evaluated.Results: The CP-treated group showed a significant reduction(P < 0.001) in the body and seminal vesicle weights, testosterone level, sperm count, sperm motility and sperm viability, but elevated(P < 0.001)sperm morphological abnormalities and testicular structure alterations, compared to the control group.Interestingly, these detrimental effects of CP were reversed by treatment with H. odoratissimum extracts.For instance, both extracts and all doses of H. odoratissimum significantly increased the sperm count(P < 0.001), sperm motility(AE, 50 mg/kg, P < 0.05;ME, 50 and 100 mg/kg, P < 0.05) and sperm viability(AE, 50 mg/kg, P < 0.001;ME, 50 and 100 mg/kg, P < 0.001) compared to the CP group. H. odoratissimum also improved plasmatic and intratesticular testosterone levels and prevented histological alterations of the testes.Conclusion: H. odoratissimum might be considered as an alternative drug to alleviate/prevent reproductive damage in cancer patients receiving CP chemotherapy.

关键词： Helichrysum odoratissimum Cyclophosphamide Reproductive toxicity Rat