Control of Senecio jacobaea L. (ragwort) by autumn or spring herbicide application

A range of herbicides was sprayed in October 1976 or May 1977 on grassland infested with S. jacobaea. Control, measured by reduction in the number of flowering stems in July 1977, was extremely good with all herbicides, October spraying gave 99% control of 5. jacohaea and is provisionally recommended for grassland which is to be cut for silage. Lutte contre Senecio jacobaea L. (séneçonjacobée) parun traitement herbicide d'automne ou de printemps Une série d'herbicides ont été appliqués en octobre 1976 ou en mai 1977 sur des herbages infestés de séneçon jacobée. L'éfficacité, mesurée par la réduction du nombre de tiges fleuries en juillet 1977, a été extrêmement bonne avec tous les herbicides. Le traitement d'octobre a détruit 99% de S. jacobaea; il est provisoirement recommande pour les prairies de fauche dont la recolte doit etre ensilee. Bekümpfung von Senecio jacobaea L. (Jakohs-Kreuzkraut) durch Herbizidanwendung im Herbst oder Frühjahr Auf Grünland, das mit Jakobs-Kreuzkraut verseucht war, wurde eine Reihe von Herbiziden im Oktober 1976 oder im Mai 1977 eingesetzt. Die Bekämpfung, gemessen am Rückgang blühender Pflanzen im Juli 1977, war mit alien Herbiziden äusserst zufriedenstellend. Die Spritzung im Oktober ergab für S. jaco baea einen Bekämpfungsgrad von 99% und wird für Grünland, das für Silagegewinnung genutzt wird, vorläufig empfohlen.     

Severe Neutropenia Associated With Griseofulvin Therapy in Cats With Feline Immunodeficiency Virus Infection

Griseofulvin administration was associated with the development of absolute neutropenia in six of seven (86%) cats with feline immunodeficiency virus (FIV) infection. The neutropenia was severe (less than 400 neutrophils/microliter) in four of the six affected cats, and one cat died from sepsis. Neutrophil counts returned to baseline values within 15 days after drug withdrawal in all surviving cats. No symptoms or hematologic abnormalities were observed in four normal (FIV-seronegative) cats treated with the same lot of griseofulvin at equivalent doses. Neutropenia recurred in two of two FIV-seropositive cats upon griseofulvin rechallenge. Cats with FIV infections appear to be at increased risk for griseofulvin-associated neutropenia. This phenomenon may be analogous to the increased frequency of antibiotic-induced neutropenias observed in humans infected with the human immunodeficiency virus.     

Esophageal Replacement in the Dog by Microvascular Colon Transfer

An orthotopic colon graft based on the middle colic artery and vein was implanted with microvascular technique and a stapling instrument in five dogs. The grafts were successful in four dogs. A similar colon autograft was used to replace the entire thoracic esophagus in five dogs. The recipient vessels were the left carotid artery and left external jugular vein. Four of the grafts failed because of kinking and thrombosis of the arterial supply (2 dogs) or the venous outflow (2 dogs). One graft, which had a viable vascular supply, developed a severe leak at the colon-to-stomach anastomosis, and the dog was euthanatized on day 3. The recipient vascular pedicle was modified and used successfully to replace a portion of the cervical esophagus in three dogs. The grafts survived, the dogs could swallow liquids and semisolid food well, and, at necropsy after 4 weeks, the anastomotic sites were well healed. The graft sites contained essentially normal colon mucosa.     

Evaluation of ear tags impregnated with cypermethrin for the control of sheep body lice (Damalinia ovis)

The application of polymer matrix ear tags impregnated with 8.5% w/w cypermethrin to 6 wethers following shearing reduced lice to non-detectable levels on 4 of them at 29 weeks after tagging. At the conclusion of the study at 45 weeks the mean count of lice on tagged wethers was 3 per sheep compared to 158 on untreated wethers. In a second experiment, 6 non-infected sheep were treated at shearing with cypermethrin tags, 6 with 25 g/l cypermethrin backline formulation, 6 with tags plus backline and 6 were left untreated. Each group was exposed to 6 sheep with moderate to heavy infestations of lice. Compared to controls, all treatments delayed infestation, but cypermethrin tags gave no longer protection than backline treatment. All sheep were infested by 17 weeks after commencement of the study. At 45 weeks mean counts of lice were 38, 27, 20 and 74 respectively for sheep treated with tags, backline formulation, backline plus tags and untreated. Possible reasons for the better effect observed from applying tags to infested sheep than to sheep which were not infected at application but which were subsequently exposed to infested sheep are discussed.     

Effects of dietary arginine and lysine levels on growth performance and biochemical parameters of juvenile Japanese flounder Paralichthys olivaceus

ABSTRACT: To investigate the effects of disproportionate levels of dietary arginine and lysine on juvenile Japanese flounder Paralichthys olivaceus , growth performance and biochemical parameters were evaluated by feeding five test diets, comprising different levels of arginine and lysine, to triplicate groups of juveniles (initial bodyweight 1.85 g) for 40 days. Crystalline amino acids were supplemented to test diets to correspond to the amino acid pattern found in the whole body protein of the Japanese flounder, except for arginine and lysine. After the feeding trials, plasma arginine, lysine and urea levels, excreted ammonia-N, and liver arginase activity were analysed. Survival, specific growth rate, feed conversion efficiency, and apparent protein retention were adversely affected ( P  <   0.05) by the deficiency in dietary arginine or lysine concentrations. An excess of either lysine or arginine in the diet did not depress growth when the diets contained adequate levels of either arginine or lysine, proving that there is no evidence for an arginine–lysine antagonism. Results for plasma arginine, lysine and urea levels, excreted ammonia, and liver arginase activity also demonstrated that Japanese flounder juveniles are not sensitive to excess dietary levels of lysine and arginine.     

Computer simulations of homeward-migrating Fraser River sockeye salmon: is compass orientation a sufficient direction-finding mechanism in the north-east Pacific Ocean?

Computer simulations were used to investigate whether compass orientation is a sufficient guidance mechanism for sockeye salmon migrating to the Fraser River from their ocean foraging grounds in the north-east Pacific Ocean. Daily surface ocean currents, simulated by the ocean surface current simulations (OSCURS) model, were used to test the influence of currents on the return oceanic migration of Fraser River sockeye salmon. High seas tagging and coastal recover data of Fraser River sockeye salmon were used for the migration simulations. Surface currents were shown to increase the speed of the homeward-migrating sockeye salmon, as well as to deflect the fish in a north-eastward direction. In spite of ocean currents, all Fraser River sockeye salmon were able to reach their destination with a fixed direction and bioenergetically efficient swimming speed when migration was delayed until the last month at sea. Compass orientation alone was shown to be a sufficient direction-finding mechanism for Fraser River sockeye salmon.     

Current practices in the chemotherapeutic control of sea lice infestations in aquaculture: a review

Abstract. This review surveys the available literature on the efficacy and ecotoxicology of chemotherapeutic agents for the control of sea lice (Copepoda: Caligidae) infestations in marine aquaculture. To date, treatment for the disease has relied almost exclusively on the use of the organophosphorus pesticides, trichlorfon and dichlorvos. While use of dichlorvos and trichlorfon appears to have little, if any, environmental impact, protracted use in some areas has led to reduced efficacy. Compounds proposed for sea lice control currently under field evaluation include azamethiphos (organophosphate), ivermectin (avermectin), pyrethrum (pyrethrin) and hydrogen peroxide. Although all of these compounds are effi cacious, at present published information on marine environmental toxicology is scarce and is limited to in vitro toxicity testing. Other compounds that have been considered for sea lice control include formalin, malathion (organophosphate), carbaryl (carbamate), diflubenzuron (insect growth regulator) and natural remedies (i.e. onions and garlic). In general, formaldehyde (aldehyde), malathion and natural compounds show either poor efficacy or unsuitable therapeutic margins. Although carbaryl and diflubenzuron are both efficacious and exhibit suitable therapeutic margins, available data suggests that the compounds, due to undesirable environmental toxicological characteristics, would be unsuitable for sea lice control.