Harbour porpoises exhibit localized evasion of a tidal turbine

1. Tidal energy generators have the potential to injure or kill marine animals, including small cetaceans, through collisions with moving turbine parts. Information on the fine scale behaviour of animals close to operational turbines is required to inform regulators of the likely impact of these new technologies.
2. Harbour porpoise movements were monitored in three dimensions around a tidal turbine for 451 days between October 2017 and April 2019 with a 12-channel hydrophone array.
3. Echolocation clicks from 344 porpoise events were localized close to the turbine. The data show that porpoises effectively avoid the turbine rotors, with only a single animal clearly passing through the rotor swept area while the rotors were stationary, and none passing through while rotating.
4. The results indicate that the risk of collisions between the tidal turbine and porpoises is low; this has important implications for the potential effects and the sustainable development of the tidal energy industry.

     

昆虫病原真菌在当前和未来的温室生态系统中的作用

There are several biopesticides based on entomopathogenic fungi available in the market for use against insect pests in greenhouse ecosystems.Although most are compatible for use with predators and parasitoids in greenhouse ecosystems,much more research is needed to determine the intraguild interactions for each combination of host, pathogen, predator, and parasitoid.Our research has demonstrated that, although direct effects on the predators could be demonstrated in laboratory bioassays, different results were found under greenhouse conditions, indicating that results obtained in the laboratory may be a poor predictor of what occurs in the greenhouse.In both cases, additive effects were obtained under greenhouse conditions,demonstrating compatibility. In addition, there is increasing evidence that entomopathogenic fungi have significant potential for dual management of invertebrate pests and plant pathogens.Our studies demonstrated that 3 species of Lecanicillium had significant effects on both aphids and cucumber powdery mildew, Sphaerotheca fuliginea;that the fungus Paecilomyces fumosoroseus was compatible with a mirid predator,Disyphus hesperus,when used concurrently against greenhouse whitefly,Trialeurodes vaporariorum;and that Lecaniciullium longisporum was compatible with a predatory midge,Aphidoletes aphidimyza when used concurrently against green peach aphids.     

Experimental transmission of bovine viral diseases by insemination with contaminated semen or during embryo transfer

Three experimental approaches were used to study transmission of blue tongue (BT), infectious bovine rhinotracheitis (IBR) and bovine virus diarrhoea (BVD) viruses. These were insemination with contaminated semen, experimental infection of embryo donor cows, or transfer of embryos experimentally exposed to virus in vitro to normal recipients. Parameters assessed included number and quality of embryos produced, virus detection (isolation and electron microscopy), serology and histopathology. All superovulated sesceptible cows inseminated with semen containing blue tongue virus (BTV) (n = 2) or infectious bovine rhinotracheitis virus (IBRV) (n = 2) became infected. One cow inseminated with semen containing BTV produced seven virus-free seven-day-old embryos; the second cow failed to produce any embryos. One of two cows inseminated with semen containing IBRV produced two underdeveloped, virus-free embryos while no embryos were produced by the second cow. One of two cows inseminated with semen containing bovine viral diarrhoea virus (BVDV) became infected. Two poorly developed, virus-free seven-day-old embryos were recovered from one of these cows. Superovulated susceptible cows inoculated either intramuscularly with BTV (n = 3) or intranasally with IBR virus (n = 2) became infected. Virus was isolated from some tissues of two BTV-infected cows, neither of which produced embryos. A third BTV-infected cow produced two virus-free embryos collected at necropsy five days after inoculation. One of two cows experimentally infected with IBR virus, produced three embryos but virus was not detected either by electron microscopy (1 embryo) or in cell culture by cytopathic alterations (1 embryo).(ABSTRACT TRUNCATED AT 400 WORDS)     

PHYSIOLOGY OF THE RESPIRATORY SYSTEM, SIGNIFICANT SPECIES DIFFERENCES, MEASUREMENTS OF PULMONARY FUNCTION, NORMAL VALUES AND SIGNIFICANCE OF VARIATIONS FROM NORMAL

The respiratory system of animals can be divided for evaluation into pulmonary system and circulatory system. The pulmonary system is involved in external respiration whereas the circulatory system is involved in internal respiration. External respiration is the exchange of oxygen (O₂) and carbon dioxide (CO₂) between the environment and circulating blood by way of the lungs and internal respiration is the transport of O₂ and CO₂ between the lungs and the metabolic machinery of the body cells.     

Response of pigs to recent isolates of Coxsackievirus B5

Coxsackievirus B5 (CB5) was serially passaged five times in pigs in an attempt to establish clinical disease. No clinical signs were seen although some pigs had a transient rise in rectal temperature. Viremia was not detected although virus was isolated from nasal swabs and fecal samples. No CB5 specific fluorescence or virus was detected in any tissues of five passages by immunofluorescent test and tissue culture methods, respectively.

Brain lesions were noted in all passages; extensiveness of lesions increased slightly up to the third passage although no evidence of increasing viral replication was found. No increase in brain lesions was found in the fourth and fifth passages. The development and progress of brain lesions were similar to but less extensive than those caused by swine vesicular disease virus (SVDV) in most pigs examined. Contact pigs also showed more brain lesions than inoculated pigs. In some passages, microscopic changes also were found in the heart. All pigs exposed to CB5 had positive neutralizing antibody titres against CB5 and SVDV but became ill after challenge with SVDV. There was an anamnestic response to both viruses following challenge.     

Efficiency of feeding Duddingtonia flagrans chlamydospores to grazing ewes on reducing availability of parasitic nematode larvae on pasture

Gastrointestinal nematodes are of concern in sheep production because of production and economic losses. Control of these nematodes is primarily based on the use of anthelmintic treatment and pasture management. The almost exclusive use of anthelmintic treatment has resulted in development of anthelmintic resistance which has led to the need for other parasite control options to be explored. The blood sucking abomasal parasitic nematode Haemonchus contortus causes severe losses in small ruminant production in the warm, humid sub-tropic and tropics. This study evaluated the effectiveness of a nematode trapping fungus, Duddingtonia flagrans, in reducing availability of parasitic nematode larvae, specifically H. contortus, on pasture. Chlamydospores of D. flagrans were mixed with a supplement feed which was fed daily to a group of crossbred ewes for the duration of the summer grazing season. A control group was fed the same supplement feed without chlamydospores. A reduction in infective larval numbers was observed in fecal cultures of the fungus-fed group. Herbage samples from the pasture grazed by the fungus-fed group also showed a reduction in infective larvae. There were no significant (P > 0.05) differences in overall fecal egg count, packed cell volume or animal weight between fungus-fed and control groups. Tracer animals were placed on the study pastures at the end of the study to assess pasture infectivity. Although tracer animals were only two per group, those that grazed with the fungus-fed group had substantially reduced (96.8%) nematode burdens as compared to those from the control group pasture. Results demonstrated that the fungus did have activity against nematode larvae in the feces which reduced pasture infectivity and subsequently nematode burdens in tracer animals. This study showed that D. flagrans, fed daily to grazing ewes, was an effective biological control agent in reducing a predominantly H. contortus larval population on pasture.