Prevalence of Cryptosporidium sp in equids in Louisiana   总被引：3，自引：0，他引：3  

S U Coleman  T R Klei  D D French  M R Chapman  R E Corstvet 《American journal of veterinary research》1989,50(4):575-577

In 1985, 22 pony foals reared in a helminth-free environment were tested daily for oocysts of Cryptosporidium sp by use of fecal flotation. Oocysts were found in all foals. Oocysts were first observed in feces collected from foals 9 to 28 days after birth. The mean period of oocyst shedding was 10 days and ranged from 2 to 18 days in individual foals. Diarrhea was observed in 14 of 22 (64%) foals and began before the period of oocyst shedding. Fecal samples also were examined for other infective agents. Salmonella poona was isolated from 1 foal that did not have diarrhea, and coronavirus particles were observed in the feces of 2 foals with diarrhea. Cryptosporidium sp oocysts also were observed in feces of 2 of 17 Thoroughbred foals, 3 of 14 Quarter Horse foals, and 3 of 26 pony foals reared on pastures with their dams. Samples from pasture-reared foals were collected at irregular intervals. Of the 11 Cryptosporidium-positive fecal samples collected from pastured foals, 2 were from foals with diarrhea. A similar survey was conducted during the 1986 foaling season, using the same procedures. Examination of 300 samples from 58 Quarter Horse, Arabian, and pony foals did not detect oocysts. Daily examination of feces from 10 pony foals reared under helminth-free conditions for 30 days also failed to detect Cryptosporidium oocysts.  相似文献   

Management and economic aspects of farm deer, horses and milking sheep     

J C Cordery  L Chapman  J F Britton 《The British veterinary journal》1989,145(2):121-128

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Preliminary observations on the occurrence of the equine XO syndrome.     

A N Bruère  M G Blue  P M Jaine  K S Walker  L M Henderson  H M Chapman 《New Zealand veterinary journal》1978,26(6):145-146

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沙棘油脂     

B. Dave Oomah  土小宁  陆海 《国际沙棘研究与开发》2005,3(3):1-10,14

果实 沙棘果实由果肉（68%）、种子（23%）和果皮（7.75%）组成（Zadernowski et al.,1997）.Yang和Kallio（2001）最近发现,从中国、芬兰和前苏联（FSU）等地大量选择后采集的沙棘果实中23%～28%是种子,72%～77%是柔软的果肉/果皮.沙棘果实可提取3种油：种子油、果肉油和果皮油.不同于其他植物,沙棘果实的各部分都能合成并积累脂肪.有时果肉油和果皮油没有区别,因此统称为果实油或果肉油.沙棘叶也含油,这部分内容将在稍后部分进一步说明.  相似文献   

Soil nitrogen availability alters rhizodeposition carbon flux into the soil microbial community     

Yaying Li  Juan Wang  Fuxiao Pan  Stephen James Chapman  Huaiying Yao 《Journal of Soils and Sediments》2016,16(5):1472-1480

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Atlantic Shorelines. Natural History and Ecology     

Dave Raffaelli 《Fish and Fisheries》2008,9(2):216-217

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Reproductive seasonality in a swamp-locked African cichlid     

E. E. Reardon  L. J. Chapman 《Ecology of Freshwater Fish》2008,17(1):20-29

Abstract –  This study quantified the seasonal pattern of reproduction in a swamp-dwelling population of the African cichlid Pseudocrenilabrus multicolor victoriae. In the hypoxic waters of the Lwamunda Swamp, Uganda, P. multicolor was reproductively active throughout the year, even during the peak of the dry seasons. However, the degree of activity was seasonal, with rainfall providing a predictor of the percentage of ripe, mature females. There was no correlation between aquatic oxygen availability dissolved oxygen (DO) and either adjusted mean gonad mass or percentage of mature females, suggesting that DO is not limiting reproductive activity in this system. Reproductively mature females were larger during drier periods and may maximise their lifetime reproductive success by producing young throughout the year; but with a lower brooding efficiency. A comparison with Welcomme's (1969) study of a river-swamp system feeding Lake Victoria suggests that reproductive patterning is variable among populations of P. multicolor and may reflect adaptive response to chronically hypoxic conditions in the Lwamunda Swamp.  相似文献   

Behind the Pan‐European Convergence Path: The Role of Innovation,Specialisation and Socio‐economic Factors          下载免费PDF全文

Sheila Chapman  Valentina Meliciani 《Growth and change》2017,48(1):61-90

The paper analyses the determinants of regional disparities in per capita gross domestic product (GDP) and their evolution over time in the enlarged European Union (EU). With reference to the literature it groups EU regions on the basis of three different factors—specialisation, socio‐economic features, and innovation. It then analyses regional disparities in per capita GDP (EU‐relative and country‐relative) across groups over 2004–2011 using both non‐parametric tools and traditional regression analysis with spatial effects. The paper finds that EU‐wide convergence actually conceals growing divergence across old member regions and within new members. Coming to the factors that lie at the heart of regional disparities, country factors lose importance for newcomers but become more important for older members, notwithstanding longstanding integration. Socio‐economic factors and innovation instead become increasingly important for all areas, socio‐economic factors lying at the heart of within‐country differences and innovation more of those between regions. Finally, specialisation appears to have a lower explanatory power.  相似文献   

An economically based evaluation index for perennial and short‐term ryegrasses in New Zealand dairy farm systems          下载免费PDF全文

D. F. Chapman  J. R. Bryant  M. E. Olayemi  G. R. Edwards  B. S. Thorrold  W. H. McMillan  G. A. Kerr  G. Judson  T. Cookson  A. Moorhead  M. Norriss 《Grass and Forage Science》2017,72(1):1-21

Grazed pastures based on ryegrass species provide most of the feed for dairy cattle in New Zealand. There are many cultivars of perennial (Lolium perenne), annual and Italian (L. multiflorum), and hybrid (L. boucheanum) ryegrasses available for dairy farmers to use in pasture renewal. This study describes an index which ranks ryegrass cultivars relative to a genetic base according to the estimated economic value (EV) of seasonal dry matter (DM) traits. A farm system model was used to derive EVs (Grazed pastures based on ryegrass species provide most of the feed for dairy cattle in New Zealand. There are many cultivars of perennial (Lolium perenne), annual and Italian (L. multiflorum), and hybrid (L. boucheanum) ryegrasses available for dairy farmers to use in pasture renewal. This study describes an index which ranks ryegrass cultivars relative to a genetic base according to the estimated economic value (EV) of seasonal dry matter (DM) traits. A farm system model was used to derive EVs ($ ha^?1 calculated as change in operating profit divided by unit change of the trait) for additional DM produced in different seasons of the year in four regions. The EV of early spring DM was consistently high across all regions, whereas EV for late spring DM was moderate to low. Genotype × environment analysis revealed significant reranking of DM yield among ryegrass cultivars across regions. Hence, separate performance values (PVs) were calculated for two mega‐environments and then combined with the corresponding season and region EV to calculate the overall EV for twenty‐three perennial ryegrass and fifteen short‐term ryegrass cultivars. The difference in operating profit between the highest ranked and lowest ranked perennial ryegrass cultivar ranged from $556 ha^?1 to $863 ha^?1 year^?1 depending on region. For short‐term ryegrasses used for winter feed, the corresponding range was $394 to $478 ha^?1 year^?1. Using PV for DM yield, it was estimated that plant improvement in perennial ryegrass has added $12–$18 ha^?1 year^?1 (depending on region) operating profit on dairy farms since the mid‐1960s.  相似文献   

Mediterranean versus Atlantic monk parakeets Myiopsitta monachus: towards differentiated management at the European scale     

Jose‐Luis Postigo  Diederik Strubbe  Emiliano Mori  Leonardo Ancillotto  Inês Carneiro  Panagiotis Latsoudis  Mattia Menchetti  Liviu G Pru  Dave Parrott  Luís Reino  Anne Weiserbs  Juan Carlos Senar 《Pest management science》2019,75(4):915-922

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