Using traffic flow theory to model traffic mortality in mammals     

van Langevelde  Frank  Jaarsma  Catharinus F. 《Landscape Ecology》2004,19(8):895-907

Traffic has a considerable effect on population and community dynamics through the disruption and fragmentation of habitat and traffic mortality. This paper deals with a systematic way to acquire knowledge about the probabilities of successful road crossing by mammals and what characteristics affect this traversability. We derive a model from traffic flow theory to estimate traffic mortality in mammals related to relevant road, traffic and species characteristics. The probability of successful road crossing is determined by the pavement width of the road, traffic volume, traversing speed of the mammals and their body length. We include the traversability model in a simple two-patch population model to explore the effects of these road, traffic and species characteristics on population dynamics. Analysis of the models show that, for our parameter ranges, traffic volume and traversing speed have the largest effect on traffic mortality. The population size is especially negatively affected when roads have to be crossed during the daily movements. These predictions could be useful to determine the expected effectiveness of mitigating measures relative to the current situation. Mitigating measures might alter the road and traffic characteristics. The effects of these changes on traffic mortality and population dynamics could be analysed by calculating the number of traffic victims before and after the mitigating measures. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

A modified fluorometric method to quantify the concentration effect (pI₅₀) of photosystem II-inhibiting herbicides     

Masaki Hiraki  Wim J. Vredenberg  Jack J.S. van Rensen  Ko Wakabayashi 《Pesticide biochemistry and physiology》2004,80(3):183-191

Chlorophyll fluorescence induction curves of isolated thylakoids were measured in the absence and in the presence of various concentrations of photosystem II-inhibiting herbicides. A mathematical program was applied to simulate the curves. Based on these simulated curves a new method is developed to determine the concentration effect (pI₅₀) of the herbicides. The results of the new method correspond well with reported values in the literature. The method is very convenient and time-saving.  相似文献   

Comparison of aloe vera and omeprazole in the treatment of equine gastric ulcer syndrome          下载免费PDF全文

J. Bush  R. van den Boom  S. Franklin 《Equine veterinary journal》2018,50(1):34-40

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Elapid snake envenomation in horses: 52 cases (2006–2016)          下载免费PDF全文

N. J. Bamford  S. B. Sprinkle  L. A. Cudmore  A. M. Cullimore  A. W. van Eps  E. J. M. M. Verdegaal  B. S. Tennent‐Brown 《Equine veterinary journal》2018,50(2):196-201

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Effect of ionization,bedding, and feeding on air quality in a horse stable          下载免费PDF全文

Esther Willemijn Siegers  Milou Anthonisse  Frank J. C. M. van Eerdenburg  Jan van den Broek  Inge M. Wouters  Cornélie Martine Westermann 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(3):1234-1240

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Obituary Dr Theo Elsinghorst     

Han van der Kolk 《The Veterinary quarterly》2018,38(1):33-34

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Ergovaline does not alter the severity of ryegrass staggers induced by lolitrem B     

SC Finch  JB Vlaming  BL Sutherland  C van Koten  WJ Mace  LR Fletcher 《New Zealand veterinary journal》2018,66(2):93-97

AIM: To investigate a possible interaction between lolitrem B and ergovaline by comparing the incidence and severity of ryegrass staggers in sheep grazing ryegrass (Lolium perenne) containing lolitrem B or ryegrass containing both lolitrem B and ergovaline.

METHODS: Ninety lambs, aged approximately 6 months, were grazed on plots of perennial ryegrass infected with either AR98 endophyte (containing lolitrem B), standard endophyte (containing lolitrem B and ergovaline) or no endophyte, for up to 42 days from 2 February 2010. Ten lambs were grazed on three replicate plots per cultivar. Herbage samples were collected for alkaloid analysis and lambs were scored for ryegrass staggers (scores from 0–5) weekly during the study. Any animal which was scored ≥4 was removed from the study.

RESULTS: Concentrations of lolitrem B did not differ between AR98 and standard endophyte-infected pastures during the study period (p=0.26), and ergovaline was present only in standard endophyte pastures. Ryegrass staggers was observed in sheep grazing both the AR98 and standard endophyte plots, with median scores increasing in the third week of the study. Prior to the end of the 42-day grazing period, 22 and 17 animals were removed from the standard endophyte and AR98 plots, respectively, because their staggers scores were ≥4. The cumulative probability of lambs having scores ≥4 did not differ between animals grazing the two pasture types (p=0.41).

CONCLUSIONS AND CLINICAL RELEVANCE: There was no evidence for ergovaline increasing the severity of ryegrass staggers induced by lolitrem B. In situations where the severity of ryegrass staggers appears to be greater than that predicted on the basis of concentrations of lolitrem B, the presence of other tremorgenic alkaloids should be investigated.  相似文献   

Effects of oral administration of different dosages of carvacrol essential oils on intestinal barrier function in broilers          下载免费PDF全文

ShuDong Liu  MinHo Song  Won Yun  JiHwan Lee  ChangHee Lee  WooGi Kwak  NamSoo Han  HyeunBum Kim  JinHo Cho 《Journal of animal physiology and animal nutrition》2018,102(5):1257-1265

Essential oils are widely used in the pharmaceutical, food and cosmetic industries, and many plant essential oils have shown that they have positive effects on broilers nutrition. This experiment was conducted to study the effects of orally administered different dosages of carvacrol essential oils on intestinal barrier function in broiler chickens. A total of eighty 28‐day‐old (1.28 ± 0.15 kg) ROSS 308 broilers were randomly allocated to four groups of 20 replicates each, with one chicken per replicate per cage, and all were fed with the same diet. Four experimental groups were orally administered 0, 200, 300 or 400 μl carvacrol essential oils at 18:00 hr every day during the 2‐week experimental period. As a result of which, the gene expression of the occludin, claudin‐1, claudin‐5, ZO‐1 and ZO‐2 in intestinal mucosa of small intestine (p < 0.05) and the goblet cell content in small intestine epithelium (p < 0.05) were significantly increased; test subjects with 300 or 400 μl carvacrol essential oils reduced the microbial counts of Salmonella spp. and Escherichia coli in the intestines (p < 0.05); Essential oils administration also significantly increased activity of the sucrase (p < 0.05) and lactase (p < 0.05) in intestinal mucosa. In conclusion, the carvacrol essential oils have positive effects on growth performance and intestinal barriers function of broilers; those effects may be related to the dosage, as administration of 300 or 400 μl was more effective than that of 200 μl.  相似文献   

Viral skin diseases in the Netherlands          下载免费PDF全文

M. M. Sloet van Oldruitenborgh‐Oosterbaan  G. C. M. Grinwis 《Equine Veterinary Education》2018,30(10):558-563

The most common viral skin problems are discussed in the third article in our equine dermatology series.  相似文献   

Canine and feline cutaneous screw‐worm myiasis in Malaysia: clinical aspects in 76 cases          下载免费PDF全文

Hock Siew Han  Peik Yean Toh  Hock Binn Yoong  Hooi Meng Loh  Lee Lee Tan  Yin Yin Ng 《Veterinary dermatology》2018,29(5):442-e148

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