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Coral reefs throughout the world have been damaged by storms, diseases, coral predators, temperature anomalies, and human activities. During the past three decades, recovery has been limited and patchy. Although a damaged coral reef cannot be restored to its original condition, interest in reef restoration is increasing. In a pilot project in the Caribbean (US Virgin Islands), storm-produced fragments of Acroporapalmata, A. cervicornis, and Porites porites were collected from donor reefs and transplanted to nearby degraded reefs. Sixty coral fragments were attached to dead-coral substrate (usually A. palmata skeletons), at similar depths from which they had been collected (1-3.5 m), using nylon cable ties. Seventy-five intact colonies were designated as controls. Study colonies were assessed at 6-month intervals for 2 years (1999-2001) and annually thereafter (through 2004). One-fourth of the 135 colonies and fragments monitored were alive at the conclusion of the 5-year study. Survival of control and transplanted A.cervicornis and P. porites was very low (median survival 2.4 and 1.8 years, respectively), with no significant differences between transplant and control colonies. Site and depth did not contribute significantly to A. palmata colony survival, but colony size and transplant/control status did. Probability of survival increased with colony size. Median survival for A. palmata was 1.3 years for transplant and 4.3 years for natural colonies when not controlled for size. A. palmata was the only viable candidate for reef rehabilitation. Storm swells were the primary cause of mortality. 相似文献
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Abstract. A formalized bacterin of Vibrio anguillarum , with and without alum adjuvant, was administered intraperitoneally to rainbow trout under farm conditions. Compared with the normal bacterin the adjuvanted preparation caused pathological changes indicative of chronic peritonitis, substantial early mortalities in 3 cm fish, and to a lesser extent in 20 cm fish, and depressed growth rate. No additional degree of protection against artificial challenge was obtained from its use. 相似文献
56.
Linda G. Martin DVM MS Vicki L. Matteson RN Wayne E. Wingfield DVM MS Deborah R. Van Pelt DVM MS Timothy B. Hackett DVM MS 《Journal of Veterinary Emergency and Critical Care》1994,4(1):15-20
Serum magnesium (Mg) is an infrequnetly measured electrolyte in small animal patients. Currently, little is known about the prevalence and significance of abnormalities in serum Mg in animals. Therefore, a prospective study was performed to examine the incidence and clinical implications of abnormalities in serum Mg levels in critically ill dogs.
Serum Mg and other electrolytes were measured in 93 normal dogs housed at the Purina Pet Care Center and in 48 ill dogs admitted to a small animal critical care unit. The normal reference range for canine serum Mg was determined to be 1.89 – 2.51 mg/dl. Based on this range, 54% of the critically ill dogs were hypomagnesemic (< 1.89 mg/dl) and 13% were hypermagnesemic (> 2.51 mg/dl). Of the electrolytes measured in these patients, serum Mg had the highest prevalence of abnormal values. Hypomagnesemic patients had a significantly higher incidence of concurrent hypokalemia and hyponatremia (p < 0.05), as well as a longer length of hospitalization (p < 0.05) than their normomagnesemic counterparts. Hypermagnesemic patients were 2.6 times more likely not to survive their illness when compared to patients with normal serum Mg levels.
Abnormalities in serum Mg appear to be common in critically ill dogs. These patients commonly have other concurrent electrolyte abnormalities. Since serum Mg is not routinely measured, the presence of hypokalemia or hyponatremia should alert the clinician to the possibility of coexisting hypomagnesemia. The clinical implications of hypomagnesemia and hypermagnesemia in ill dogs appear to involve prolonged hospitalization and increased mortality, respectively: however, the exact etiology remains undetermined. 相似文献
Serum Mg and other electrolytes were measured in 93 normal dogs housed at the Purina Pet Care Center and in 48 ill dogs admitted to a small animal critical care unit. The normal reference range for canine serum Mg was determined to be 1.89 – 2.51 mg/dl. Based on this range, 54% of the critically ill dogs were hypomagnesemic (< 1.89 mg/dl) and 13% were hypermagnesemic (> 2.51 mg/dl). Of the electrolytes measured in these patients, serum Mg had the highest prevalence of abnormal values. Hypomagnesemic patients had a significantly higher incidence of concurrent hypokalemia and hyponatremia (p < 0.05), as well as a longer length of hospitalization (p < 0.05) than their normomagnesemic counterparts. Hypermagnesemic patients were 2.6 times more likely not to survive their illness when compared to patients with normal serum Mg levels.
Abnormalities in serum Mg appear to be common in critically ill dogs. These patients commonly have other concurrent electrolyte abnormalities. Since serum Mg is not routinely measured, the presence of hypokalemia or hyponatremia should alert the clinician to the possibility of coexisting hypomagnesemia. The clinical implications of hypomagnesemia and hypermagnesemia in ill dogs appear to involve prolonged hospitalization and increased mortality, respectively: however, the exact etiology remains undetermined. 相似文献
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SUMMARY A survey of nearly 20 000 cattle in Queensland was conducted to describe the prevalence and distribution of infection by serotypes of bluetongue virus. The overall prevalence of serum antibodies to one or more bluetongue viruses was 8.7% (95% confidence interval 8.3 to 9.1). Sera from cattle contained neutralising activity against 2 serotypes, 1 and 21. No evidence was found of infection with other serotypes previously isolated in Australia. The overall prevalence of serotype 1 antibodies was 7.7% (95% CI 7.3 to 8.0) and the prevalence of serotype 21 antibodies was 3.3% (95% CI 3.1 to 3.6). The prevalence of serotype 1 antibodies was significantly (P < 0.05) higher than that of serotype 21 in every region of the State, except in the central highlands and south-west Queensland. Overall, 3 significantly (P < 0.05) different zones of prevalence were found: high prevalence (> 20%) in far north Queensland, moderate (5 to 20%) in north-west, northern and southern coastal Queensland, and low (< 5%) in the central highlands, Darling Downs and south-west Queensland. 相似文献
59.
Characterization of Polymyxa species by restriction analysis of PCR-amplified ribosomal DNA 总被引:1,自引:0,他引:1
A molecular method is described to aid identification of the obligate parasite Polymyxa and discriminate between species ( P. betae and P. graminis ) and isolates. DNA was extracted from zoospores, resting spores and roots infected with P. betae and P. graminis and compared with that from negative control plants that were not inoculated with Polymyxa but were grown at the same time under the same conditions. The ribosomal internal transcribed spacers and 5.8S rDNAs were amplified by the polymerase chain reaction and digested with restriction enzymes to detect molecular differences between the species and isolates. There were differences between P. betae and P. graminis and two subgroups within P. graminis but so far this has not been correlated with any other biological property. 相似文献
60.
MOGENS BJ
RN NIELSEN 《水产资源保护:海洋与淡水生态系统》1996,6(3):187-190
1. In 1993 the EU Life Programme granted funds to establish a demonstration project on river and catchment restoration. The aim is to improve understanding of ecosystem diversity, the impact on biodiversity of human activities, and the restoration of natural functions and biodiversity. The total cost of the project will be approximately £5 m up to the beginning of 1997. 2. The demonstration project covers three different types of rivers and geology in the UK and Denmark. The three damaged rivers and their floodplains have been restored on stretches of several kilometres. 3. A comprehensive monitoring programme has been set up to examine the physical, chemical and biological effects of restoration for integrated catchment management, nature conservation, water quality, river hydrology, flood prevention and amenity. 4. The project will also produce reports, videos, a river restoration handbook and other material on the development, implementation and results of the project. An EU network of contacts with organizations, river managers and others with interests in river restoration will be established. 相似文献