Growth induction of common carp, Cyprinus carpio L., fry as a function of plankton density and improved water quality

Abstract. One hundred and ninety-eight fry of common carp, Cyprinus carpio L., were reared in outdoor tanks containing 9580 1 of water under five management schemes — separate live-food system (LF), intermediate system (I), static manured system (M), manured system with water exchange (EM) and supplementary food system (SF) — in triplicate for a growing period of 90 days. Examination of frequency distribution of different weight groups of fishes at the time of harvest showed a maximum proportion of larger and smaller fishes in the live-food and supplementary food system, respectively. Maximum growth and production of common carp in the LF treatment was the consequence of greater abundance of plankton food and improvement of water quality expressed in terms of higher values of pH and DO and lower values of COD and BOD.     

THE ORAL TOXICITY FOR SHEEP OF TRITERPENE ACIDS ISOLATED FROM LANTANA CAMARA

SUMMARY Toxic Lantana camara taxa growing in Queensland all contain the triterpene acids lantadene A, reduced lantadene A and lantadene B. These when dosed as pure compounds orally to sheep were similarly toxic at 65 to 75, 42 to 80 and 200 to 300 mg/kg body weight respectively, causing jaundice, photosensitisation, kidney and liver lesions typical of natural and experimental lantana poisoning. Because of its comparative toxicity and abundance lantadene A is the most significant toxic principle in the plant. Reduced lantadene A because of its low concentration in the leaves (5% of lantadene A) and lantadene B because of its significantly lower toxicity are thus unlikely to be of much importance in the poisoning of ruminants following consumption of the plant. In addition, the structural features of both lantadene A and B molecules given to sheep by the oral route do not conform to the chemical structures previously reported to be required for liver damaging action of the verbenaceous triterpenes administered to rabbits by the intraperitoneal route.     

Production,size, and germination of broad‐leaved dock seeds collected from mother plants grown under different nitrogen,phosphorus, and potassium supplies

Rumex obtusifolius is believed to be a nitrophilous weedy species that spreads mainly by seed. However, the effects of nutrient availability on seed production never have been investigated. In this study, how the amount of seed production per plant, the chemical composition of the seeds, and their size and germination are affected by the supply of N, P, and K was investigated. A pot fertilizer experiment with 10 treatments (combinations of 0, 150 [N1], and 300 [N2] kg N ha^?1, 0, 40 [P1], and 80 [P2] kg P ha^?1, and 0 and 100 [K] kg K ha^?1 applied twice per vegetation season) was carried out in Prague, Czech Republic, in 2008 and 2009. The seeds from plants that were cultivated since the spring were collected each August. The germination of the seeds was determined in long‐daylight conditions at a stable temperature of 20°C. The number of seeds per plant ranged from 0 in the P1 and P2 treatments and <200 in the control and K treatments to almost 9000 in the N2P2K treatment. The number of seeds per plant was positively correlated with the number of stems per plant and the number of seeds per stem. The relationship between the amount of seeds per plant and the individual seed weight was positive. The concentration of N, P, and K in the seeds was affected by the treatments. The weight of 1000 seeds ranged from 1.3 to 1.7 g. The seed length ranged from 2.11 to 2.34 mm and the seed width varied from 1.26 to 1.42 mm. With the exception of the control (with 94% germination), the amount of seed germination was >98% in all the other treatments in 2008. In 2009, the amount of seed germination was >95% in all the treatments, except N1 and N2, where 93% and 89% germination, respectively, was recorded. The germination rate was positively related to the P concentration in the seeds. The amount of time that was necessary for 50% seed germination ranged from 1.53 to 2.89 days and was not related to the N concentration in the seeds, but it was negatively related to the P and K concentrations. A balanced N, P, and K supply to the mother plant strongly affected the number of produced seeds and their chemical composition and germination ability.     

Exostoses in hypervitaminotic A cats with optimal calcium—phosphorus in takes

Exostoses typical of those previously described in chronic hypervitaminosis A of the cat were produced in six cats fed liver selected for high vitamin A content, and in six cats fed mince low in vitamin A and supplemented with the vitamin by capsule. In contrast to the previous work, the mineral content of each diet was adjusted to be more than adequate in calcium and phosphorus and optimal in calcium/phosphorus ratio. It was concluded that the levels and relative proportions of calcium and phosphorus in the diet have little or no influence of the development of exostoses in chronic hypervitaminosis A in the cat, and that the American disease ‘osteodystrophy in mature cats’ probably has a different aetiology. Resumé. On a provoqué des exostoses décrites comme manifestation typique de l'hypervitaminose A du chat en administrant s? 6 animaux du foie sélectionné pour sa forte teneur en vitamine A et à six autres chats du hachis de foie pauvre en cette vitamine, mais supplémenté par des capsules de vitamines. Contrairement à ce qui a été fait dans des études antérieures, les concentrations en minéraux on été ajustées de façon à être plus qu'adéquates en ce qui concerne le calcium et le phosphore et le rapport optimal calcium: phosphore. On conclut que les teneurs en calcium et en phosphore ainsi que le rapport entre ces deux éléments dans le régime n'ont que peu ou pas du tout d'influence sur le développement des exostoses au cours de l'hypervitaminose A chronique du chat et que le syndrome décrit par les Américains sous le nom de ‘ostéodystrophie du chat adulte’ relève sans doute d'une étiologie différente. Zusammenfassung. Exostosen typisch in der Art, wie sie früher bei chronischer A-Hypervitaminose der Katze besprochen wurden, liessen sich bei sechs Katzen hervorrufen, die mit Leber gefüttert wurden, welche nach ihrem hohen Vitamin-A-Gehalt ausgewählt worden war, und bei sechs Katzen, die Hackfleisch mit geringem Vitamin-A-Gehalt als Futter erhielten, das durch das Vitamin in Kapseln ergänzt wurde. Im Gegensatz zu der früheren Untersuchung wurde der Mineralgehalt beider Futterarten auf mehr als ausreichend im Calcium- und Phosphorgehalt und auf optimal hinsichtlich des Calcium/Phosphor-Verhüaltnisses eingestellt. Es wurde daraus der Schluss gezogen, dass die Konzentrationen und das Mengenverhaltnis von Calcium und Phosphor im Futter wenig oder keinen Einfluss auf die Entwicklung von Exostosen bei chronischer A-Hypervitaminose bei der Katze hatten und dass die amerikanische Krankheit ‘Osteodystrophie bei erwachsenen Katzen’ wahrscheinlich eine andere Ätiologie besitzt.     

COMPARATIVE ASSESSMENT OF TOXICITY OF PHENOL,FORMALDEHYDE, AND INDUSTRIAL WASTEWATER TO AQUATIC ORGANISMS

The toxicity of pure phenol, formaldehyde, and industrial wastewater, containing phenol and formaldehyde, from a resin production plant was evaluated using aquatic organisms from different taxonomic groups. Test organisms included mixed bacterial culture, unicellular green algae Scenedesmus quadricauda (Turp.) Breb., crustacea Daphnia pulex de Geer (daphnids), and fish Oncorhynchus mykiss Call, 1990 (rainbow trout). Formaldehyde was found to be more toxic to the mixed bacterial culture (120h EC₅₀ = 34.1 mg L^-1), algae (24h EC₅₀ = 14.7 mg L^-1), and crustacea (48h EC₅₀ = 5.8 mg L^-1) than phenol. Phenol proved to be more toxic to fish (48h LC₅₀ = 13.1 mg L^-1) than to the mixed bacterial culture (120h EC₅₀ = 510 mg L^-1), algae (24h EC₅₀ = 403 mg L^-1), and crustacea (48h EC₅₀ = 25 mg L^-1). The toxicity of the industrial wastewater to the mixed bacterial culture, algae, and crustacea was caused mainly by formaldehyde, but for fish the presence of phenol in the wastewater proved to be the significant reason for toxicity. Differences in sensitivity of the selected test organisms were also observed, with fish and crustacea being the most sensitive species.