摘要:

The mysidNeomysis mercediswas examined as a test organism for use in acute toxicity tests at intermediate salinities characteristic of estuarine waters. Several sensitive invertebrate species are available for marine assessments (mysids) and freshwater tests (cladocerans), but few are available for estuarine toxicity tests. Observations in the laboratory indicate thatNeomysis mercediscan be reared successfully at a temperature of 17°C, a salinity of 2‰, and a population density less than 5/L. Brine shrimp naupliiArtemia salina, algae, and commercial foods were used to sustain mysid cultures.Neomysis mercedisis viviparous and can complete its life cycle in 3–4 months.Neomysis mercedisis as sensitive as or more sensitive to toxicants than the marine mysid Mysidopsis bahia and the freshwater cladoceransDaphnia magna,Ceriodaphnia dubia, andSimocephalus serrulatus. The mean 96-h LC50 values (concentrations lethal to half the test animals) forN. mercedis, in increasing order, were 0.20 μg/L for methyl parathion, 2.2 μg/L for malathion, 14 μg/L for carbofuran, 150 μg/L for copper sulfate, 280 μg/L for thiobencarb, and 1,600 μg/L for molinate. Neonates (5 d postrelease) were generally more sensitive than older juveniles. Coefficients of variation (100·SD/mean) of LC50 values varied from 21 to 35%.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1993)122<0279:UONMCM>2.3.CO;2

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A chloride suspension in saline with 12.7 μg of dysprosium or europium, or with 127 μg samarium, or with a mixture containing 12.7 μg Dy, 12.7 μg Eu, and 254 μg Sm, was injected interperitoneally in fingerling rainbow troutOncorhynchus mykiss. The retention and tissue distribution of these rare-earth marks, and the effects of these marks on fish growth and development, were monitored for 763 d. Rare earth element concentrations in the fish were determined by neutron activation analysis. Mark retention and tissue distribution were similar in fish receiving the lanthanides singly or in combination. Soon after injection, over 90% of each element was associated with the gut. As the fish developed toward sexual maturation, small amounts of the injected elements were detected in the kidneys and gonads. After treatment, small amounts (<2%) of Sm were recovered from the liver during the first year but not thereafter. Levels of Dy and Eu declined by 40–50% during the first 6 months, but they remained stable for the next 1.5 years. Conversely, Sm levels in the fish were unchanged over the 2-year study period, even though this element became concentrated in different tissues over time. Physiological effects of marking were restricted to a transient increase in the weight of the gut relative to body weight and a slight edema in the kidney, especially in fish receiving the mixture of elements. Growth and sexual development were unaffected by the treatments.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1993)122<0289:REEAIB>2.3.CO;2

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Sections of sagittal otoliths and dorsal fin rays from summer flounderParalichthys dentatuswere examined for fluorescent bands after injection with calcein and oxytetracycline at dosages of 25 mg/kg and 50 mg/kg of body weight. Fish were held alive 36 to 194 d after injection. Differences in holding times were due to mortalities attributed to a toxic red tide. Sagittae and dorsal fin rays were stored in darkness for 18 months prior to examination. No bands were seen on dorsal fin rays. Both fluorophors produced readable marks on sagittae when injected intramuscularly at each dosage rate; however, calcein bands were more intense than tetracycline bands. Tetracycline appeared detrimental to the health of the fish, causing reduced activity and cessation of feeding, whereas calcein did not.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1993)122<0298:NCOCAT>2.3.CO;2

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Rotenone was administered in a food bolus by gavage to common carpCyprinus carpio. The experimental formulations also contained a constant level of a surfactant, polysorbate 80. The lethal dose of rotenone to 50% of the test animals (LD50) was 8.1 mg/kg of fish with a 95% confidence interval of 7.7–8.5 mg/kg. The extrapolated lethal dose to 99% of the test animals was 11.6 mg/kg. Behavior of the fish receiving an oral dose of rotenone was similar to that of fish exposed to rotenone in water, and all deaths occurred within 16 h of gavage. Rotenone was made available for absorption via the intestine by including a surfactant in the formulation.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1993)122<0302:OTORFC>2.3.CO;2

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/1548-8659-122.2.305

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor