Evaluation of a virus-insecticide combination for cotton pest control in Togo     

P. Silvie  P. Le Gall  B. Sognigbe   《Crop Protection》1993,12(8):591-596

A low dose of cypermethrin combined with Mamestra brassicae virus was applied weekly against the bollworms Helicoverpa armigera (Hübner) and Diparopsis watersi (Rothschild) in smallholder cotton plots in northern Togo in 1989 and 1990. The timing of treatments was based on action thresholds. One or two additional sprays of Bacillus thuringiensis were applied to control Syllepte derogata F., or dimethoate to control aphids. No significant yield differences were observed between the plots treated with the pyrethroid-virus combination and the control plots, treated with the recommended insecticide schedule. However, the latter had a significantly higher percentage of healthy bolls. The virus applied was not reisolated from insects collected in the field.  相似文献   

The potential impact of summer flounder (Paralichthys dentatus) aquaculture on regional flounder price     

Christopher F. Dumas  Shawn Horton 《Aquaculture Economics & Management (Blackwell Science)》2013,17(1-2):39-54

Abstract

Increasing consumer demand for flounder and dramatic reductions in ocean flounder harvests have raised interest in summer flounder (Paralichthys dentatus) aquaculture. Flounder farmers have several potential markets, including regional seafood dealers and high‐end niche (e.g., sashimi and ike‐jime) buyers. Prices paid by buyers are exogenous to typical aquacultural budgeting models, yet they are a key determinant of potential profitability. We develop a simple economic model to assess the impacts of aquaculture industry supply on prices paid by regional seafood dealers. The model is parameterized for a region with established flounder dealers and active field research in flounder production methods. We derive the price elasticity of regional seafood dealer demand for farmed flounder, and we examine the impacts of changes in production cost and ocean harvest on regional price and the level of aquacultural production that maximizes returns to the aquaculture industry.  相似文献   

A live weight–heart girth relationship for accurate dosing of east African shorthorn zebu cattle     

Maia Lesosky  Sarah Dumas  Ilana Conradie  Ian Graham Handel  Amy Jennings  Samuel Thumbi  Phillip Toye  Barend Mark de Clare Bronsvoort 《Tropical animal health and production》2012,45(1):311-316

The accurate estimation of livestock weights is important for many aspects of livestock management including nutrition, production and appropriate dosing of pharmaceuticals. Subtherapeutic dosing has been shown to accelerate pathogen resistance which can have subsequent widespread impacts. There are a number of published models for the prediction of live weight from morphometric measurements of cattle, but many of these models use measurements difficult to gather and include complicated age, size and gender stratification. In this paper, we use data from the Infectious Diseases of East Africa calf cohort study and additional data collected at local markets in western Kenya to develop a simple model based on heart girth circumference to predict live weight of east African shorthorn zebu (SHZ) cattle. SHZ cattle are widespread throughout eastern and southern Africa and are economically important multipurpose animals. We demonstrate model accuracy by splitting the data into training and validation subsets and comparing fitted and predicted values. The final model is weight^0.262?=?0.95?+?0.022 × girth which has an R ² value of 0.98 and 95 % prediction intervals that fall within the ±20 % body weight error band regarded as acceptable when dosing livestock. This model provides a highly reliable and accurate method for predicting weights of SHZ cattle using a single heart girth measurement which can be easily obtained with a tape measure in the field setting.  相似文献   

Signs of age in the zebu. Study of its permanent incisors     

R Dumas  P Lhoste 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1966,19(3):357-363

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Variation of the life-weight and the meat output in Adamawa zebus during the dry season     

R Dumas  P Lhoste 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1966,19(4):573-579

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Crystal structure of the GpIbalpha-thrombin complex essential for platelet aggregation     

Dumas JJ  Kumar R  Seehra J  Somers WS  Mosyak L 《Science (New York, N.Y.)》2003,301(5630):222-226

Direct interaction between platelet receptor glycoprotein Ibalpha (GpIbalpha) and thrombin is required for platelet aggregation and activation at sites of vascular injury. Abnormal GpIbalpha-thrombin binding is associated with many pathological conditions,including occlusive arterial thrombosis and bleeding disorders. The crystal structure of the GpIbalpha-thrombin complex at 2.6 angstrom resolution reveals simultaneous interactions of GpIbalpha with exosite I of one thrombin molecule,and with exosite II of a second thrombin molecule. In the crystal lattice,the periodic arrangement of GpIbalpha-thrombin complexes mirrors a scaffold that could serve as a driving force for tight platelet adhesion. The details of these interactions reconcile GpIbalpha-thrombin binding modes that are presently controversial,highlighting two distinct interfaces that are potential targets for development of novel antithrombotic drugs.  相似文献   

Presence and accumulation of fungitoxic substances against Ceratocystis ulmi in Ulmus americana: possible relation to induced resistance1     

R. S. Jeng  A. C. Alfenas  M. Hubbes  M. Dumas 《Forest Pathology》1983,13(4):239-244

This paper reports the differential accumulation of inhibitory compounds in American elm seedlings after inoculation with a non-aggressive and an aggressive strain of C, ulmi.  相似文献   

Transpiration of four common understorey plant species according to drought intensity in temperate forests     

Rémy Gobin  Nathalie Korboulewsky  Yann Dumas  Philippe Balandier 《Annals of Forest Science》2015,72(8):1053-1064

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Haemonchus contortus egg excretion and female length reduction in sheep previously infected with Oestrus ovis (Diptera: Oestridae) larvae     

Terefe G  Yacob HT  Grisez C  Prevot F  Dumas E  Bergeaud JP  Dorchies P  Hoste H  Jacquiet P 《Veterinary parasitology》2005,128(3-4):271-283

Mixed parasitic infection of animals is a common phenomenon in nature. The existence of one species often positively or negatively influences the survival of the other. Our experimental study was started with the objectives to demonstrate the interaction of Haemonchus contortus and Oestrus ovis in relation to cellular and humoral immune responses in sheep. Twenty-two sheep of Tarasconnais breed (France) were divided into four groups (O, OH, H and C) of five or six animals. Group O and OH received 5 weekly consecutive inoculations with O. ovis L1 larvae (total = 82 L1) in the first phase of the experiment between days 0 and 28. On the second phase, groups OH and H received 5000 L3 of H. contortus on day 48 while group C served as our control throughout the experimental period. Parasitological, haematological, serological and histopathological examinations were made according to standard procedures and all animals were slaughtered at day 95. There was no significant variation in the number and degree of development of O. ovis larvae between the two infected groups. Furthermore, in tissues examined in the upper respiratory tract (nasal septum, turbinate, ethmoide and sinus), group O and OH has responded similarly on the basis of cellular inflammatory responses (blood and tissue eosinophils, mast cells and globule leucocytes (GL)) and serum antibody responses against the nasal bots. This may indicate that the presence of H. contortus in the abomasa of group OH had no marked influence over the development of O. ovis larvae in the upper respiratory tract. On the other hand, we have observed a significantly lower H. contortus female worm length, fecal egg count (FEC) and in utero egg count in animals harbouring the nasal bot (OH) than in the mono-infected group (H). This was significantly associated with higher blood eosinophilia, higher packed cell volume (PCV) and increased number of tissue eosinophils and globule leucocytes. We conclude that, the establishment of O. ovis larvae in the upper respiratory tract has initiated higher inflammatory cellular activity in group OH there by influencing the development and fecundity of H. contortus in the abomasum.  相似文献   

Post-operative analgesic effects, after orthopaedic surgery in the dog, of loco-regional ropivacaine and bupivacaine blockade using the nerve locator technique: 159 cases     

Dumas MP  Ravasio G  Carotenuto AM  Boiocchi S  Jacchetti A  Bronzo V  Fonda D 《Veterinary research communications》2008,32(Z1):S283-S286

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