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Active habitat selection by pre-settlement reef fishes 总被引:10,自引:0,他引:10
John Charles Montgomery Nicholas Tolimieri & Olivia Sophie Haine 《Fish and Fisheries》2001,2(3):261-277
Our understanding of habitat selection by reef fish larvae has changed dramatically in the last 10 years. Fish larvae have long been considered passive particles at the mercy of ocean currents, tides and weather events. For reef fishes, ecological evidence has shown that passive dispersal alone often cannot explain larval distributions, suggesting active behaviour by reef fish larvae. While behaviourally modified passive transport may be important, recent work demonstrates that some reef fish larvae have the capability to actively swim to settlement habitat. They can orientate to reefs from distances of at least 1 km and can swim at speeds of 13.5 cm s?1 for several days. The question then becomes, what are the cues that fish larvae use to orientate to reefs? Ambient reef sound has been shown to be attractive to reef fish larvae, and current research aims to understand better the nature and use of these acoustic cues. Other potential cues include chemoreception/olfaction, wave cues and visual location of reefs. A better understanding of active habitat selection and the underlying sensory and behavioural mechanisms will improve our knowledge of recruitment processes in reef fish ecology, and may have implications for active management of reef fish populations. 相似文献
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Heidrun Gehlen Sophie Twickel Sabita Stöckle Corinna Weber Claus P. Bartmann 《Journal of animal physiology and animal nutrition》2020,104(2):679-689
Pituitary pars intermedia dysfunction is the most prevalent endocrine disease in horses. Although donkeys and mules may also be affected, only a few data have been published. Reference values for diagnostic parameters, such as adrenocorticotropic hormone (ACTH), are especially scarce or even lacking. Therefore, in the present study, available data from the literature have been verified and completed to facilitate a reliable diagnosis. Clinical inspections and haematological and biochemical examinations were carried out four times in a three-month interval (February to November) in 44 donkeys and 31 mules. Data from clinically healthy animals were used as an orientation. Plasma ACTH concentrations showed seasonal changes in both animal groups. However, it was generally higher in donkeys than mules. Although blood glucose (EDTA plasma) showed no difference between groups, serum insulin concentrations were consistently higher in donkeys. Serum fructosamine levels were slightly higher in mules, whereas, in some cases, serum triglyceride levels were considerably higher in donkeys. Serum gamma-glutamyltransferase showed a striking peak in mules in August, whereas the remaining gamma-glutamyltransferase values were lower compared to donkeys. By comparing donkeys and mules, the present work reveals differences in various blood parameters which should be considered for diagnoses and future studies. 相似文献
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Cruz-Migoni A Hautbergue GM Artymiuk PJ Baker PJ Bokori-Brown M Chang CT Dickman MJ Essex-Lopresti A Harding SV Mahadi NM Marshall LE Mobbs GW Mohamed R Nathan S Ngugi SA Ong C Ooi WF Partridge LJ Phillips HL Raih MF Ruzheinikov S Sarkar-Tyson M Sedelnikova SE Smither SJ Tan P Titball RW Wilson SA Rice DW 《Science (New York, N.Y.)》2011,334(6057):821-824
The structure of BPSL1549, a protein of unknown function from Burkholderia pseudomallei, reveals a similarity to Escherichia coli cytotoxic necrotizing factor 1. We found that BPSL1549 acted as a potent cytotoxin against eukaryotic cells and was lethal when administered to mice. Expression levels of bpsl1549 correlate with conditions expected to promote or suppress pathogenicity. BPSL1549 promotes deamidation of glutamine-339 of the translation initiation factor eIF4A, abolishing its helicase activity and inhibiting translation. We propose to name BPSL1549 Burkholderia lethal factor 1. 相似文献
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The majority of bitches that are brought to a veterinarian for reproductive evaluation are actually healthy. Infertility in the bitch is most commonly due to inappropriate breeding management rather than an inability to conceive. Before embarking on an exhaustive medical evaluation, it is important to obtain a thorough history and physical examination to identify any problems. Completion of a routine database assists in detecting significant systemic illness that may impact infertility. After consideration of history, physical examination, and minimum database, fertility problems are most commonly considered in one of four categories: abnormal estrous cycles, normal estrous cycles, failure to breed, or failure to carry a litter to term. This classification system aids in construction of a differential list and systematic evaluation of all differentials. The majority of diagnostic tests required are available to the general practitioner. Before any treatment for infertility, adequate health management must be ensured. Specific treatment for the most common causes of infertility is centered on appropriate breeding management. 相似文献
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Incidence and risk factors for neurological signs after attenuation of single congenital portosystemic shunts in 253 dogs 下载免费PDF全文
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Sophie Adamantos Dez Hughes 《Veterinary Clinics of North America: Small Animal Practice》2008,38(3):719-25, xiv
Fluid therapy in patients with pulmonary disease is challenging. Although a single set of rules cannot be applied to every patient, the following guidelines can be used when managing patients with pulmonary disease. Euvolemic patients with adequate tissue perfusion should be given sufficient isotonic fluid to balance insensible losses. If severe pulmonary compromise is present, cessation of all fluid therapy may be considered if the patient is able to match its losses by voluntary intake. In hypovolemic or hypotensive patients, small boluses of isotonic crystalloids or colloids should be given to restore perfusion, avoiding rates of more than 30 mL/kg an hour for isotonic crystalloids. If perfusion is not restored by adequate volume resuscitation, vasopressors or positive inotropes should be administered to prevent fluid overload and deterioration in pulmonary function. 相似文献