Growth, Maturation, Induced Spawning, and Production of the First Generation of South American Catfish, Pseudoplatystoma sp., in North America

Growth, plasma steroids, and the appearance of gonads (histology and gonadosomatic index) were followed in South American catfish (surubim, Pseudoplatystoma sp.) raised in captivity in the aquaculture facility at The Ohio State University, Columbus, Ohio, USA, from 2003 until 2006. Broodstock growth showed a great individual variation and it did not seem sex dependent. The levels of 11‐ketotestosterone were high in males during the reproductive season. Three out of six females spawned after receiving two doses of carp pituitary extract (0.5 and 5 mg/kg) at 11‐h intervals. Fertilization was performed in only one female in February 2006. Egg size was 0.73 ± 0.06 mm in diameter at stripping. Two males released sperm, and it was used for fertilization. Sperm concentrations were 24 × 10⁹ and 15.5 × 10⁹ spermatozoa/mL in Male 1 and Male 2, respectively, and viability was confirmed after activation in 0.3% NaCl. Embryo survival at 9 h after fertilization was 44 and 23% for Male 1 and Male 2, respectively. Embryos hatched 15 h after fertilization. Larvae were 3.53 ± 0.09 mm in length at hatching and were successfully raised (72% survival after 2 wks) using live brine shrimp nauplii.     

Relationship between biochemical constituents of fish semen and fertility: the effect of short-term storage

Spermatozoa and seminal plasma obtained from rainbow trout and whitefish were analyzed in respect to their aspartate aminotransferase (AspAT) and alkaline phosphatase activities. In particular, the experiments characterized AspAT optimum pH, optimization of assay conditions and action of coenzyme, pyridoxal 5-phosphate (vitamin B₆). The effect of short-term semen storage at 0°C on biochemical indicators and fertilization rate was examined in both species. The concentrations of reduced and oxidized ascorbic acid in seminal plasma of both species were several folds higher than in spermatozoa and blood plasma of fish. Highly significant correlations were found for both species between AspAT activity (sperm or seminal plasma) and fertilization rate (% of eyed-stage or hatched embryos). For rainbow trout, highly significant correlations were found between sperm concentration, motility and fertilization rate. These results suggest that several biochemical indicators of seminal plasma can be used as measures of sperm quality of fish. Some common biochemical parameters for fish and mammal's semen provide evidence for using fish sperm as a model in biomedical research.     

Conventional and molecular cytogenetics of the pikeperch (Sander lucioperca L.)

Pikeperch (Sander lucioperca L.) is a percid fish species of high commercial value and potential for being aquacultured in Europe. As such, pikeperch needs to be karyologically studied with special attention dedicated to arrangement of the homologous chromosomes into pairs and chromosomal location of the chosen DNA sequences. The karyotype of the pikeperch consists of 48 small chromosomes: One pair of metacentric chromosomes, 15 pairs of submetacentric chromosomes and eight pairs of subtelo‐acrocentric chromosomes (FN = 80). Original data on the chromosomal distribution of early and late replication regions, segments resistant to AluI, DdeI, HinfI and HaeIII restriction endonucleases and identification of the C‐banded heterochromatin presented herein have been used to arrange pikeperch chromosomes into the karyotype. After Primed in situ labeling (PRINS) technique with primers enabling amplification of 5S rDNA sequences, hybridization spots observed on the short (p) arms of two the largest pikeperch submetacentric chromosomes (no. 2). Fluorescence in situ hybridization (FISH) with telomeric PNA (Peptide Nucleic Acid) probe enabled recognition of the conservative telomeric DNA sequences on the pikeperch chromosomes. No interstitial signals were observed. The specimens studied did not show any morphologically differentiated sex chromosomes.     

Carotenoids in diets for salmonids: I. Pigmentation of rainbow trout with the individual optical isomers of astaxanthin in comparison with canthaxanthin

Visual and chemical determinations revealed that the individual optical isomers of astaxanthin were more efficacious than canthaxanthin in pigmenting the flesh of rainbow trout (Salmo gairdneri, Richardson). The visual assessment of the astaxanthin pigmentation by means of a colour scale correlated well with the chemical determination. The same utilization was found for all three astaxanthin isomers, (3S, 3′S)-, (3R, 3′S)-, (3R, 3′R)-astaxanthin and a 1 : 2 : 1 mixture of the three isomers.No epimerization took place at the chiral centres of C-3 and C-3′ in astaxanthin. Astaxanthin and canthaxanthin were not interconverted. No metabolites were detected in the flesh.     

The cadmium status of horses from central Europe depending on breed, sex, age and living area

The Cd status of animals is best reflected by kidneys and much worse by liver and hair. Breed (heavy- and warm-blooded horses) only took an insignificant effect on the Cd content of kidneys and liver. On the average, however, warm-blooded horses stored more Cd than heavy ones. Geldings from Cd-exposed living areas accumulated insignificantly more Cd in liver, kidneys and hair than mares. The influence of age on the Cd content of kidneys and liver of Cd-exposed horses was significant. The Cd exposure of a living area was very well reflected by kidneys and liver. On the average, horses from two areas with nonferrous metal smelting stored 1000 mg Cd/kg kidney dry matter and 100 to 200 mg Cd/kg liver dry matter. The highest Cd concentration of the kidneys of horses amounted to 2.6 and 2.3 g/kg dry matter, resp.     

Enhancement of attraction and trap catches of the old-house borer, Hylotrupes bajulus (Coleoptera: Cerambycidae), by combination of male sex pheromone and monoterpenes

Monoterpenoid compounds extracted from wood of Scots pine, Pinus sylvestris L, synergized the attraction of the old-house borer, Hylotrupes bajulus (L), to the male pheromone (3R)-3-hydroxy-2-hexanone ((3R)-ketol) + 1-butanol. Glasshouse experiments using ground traps baited with extracts derived from Scots pine wood or the monoterpenes (+)-alpha-pinene, (-)-verbenone, (-)-trans-pinocarveol and (+)-terpinen-4-ol attracted significantly more H bajulus females, but caught fewer of them, than the synthetic pheromone mixture alone. Traps baited with higher concentrations of the monoterpene mixture attracted fewer females than those baited with lower dosages, whilst very high concentrations of the mixture (6-10 vials) caught no insects. However, a combination of (3R)-ketol + 1-butanol or (+/-)-3-ketol + 1-butanol with monoterpenes resulted in the capture of significantly more females than either the sex pheromone or the monoterpene mixture alone. Traps baited with a blend of the male's sex pheromone or the monoterpenes attracted significantly more, but caught fewer, males than females. Here again, a combination of the above blends enhanced the attraction of males significantly when compared with the attractancy of either of the compounds/mixtures used alone.     

The supply of wild ruminants with major and trace elements. 1. The cadmium content of winter grazing and the cadmium status of red deer, fallow deer, roes and moulons

The Cd-determination of 10 different winter grazings for wild ruminants in seven different biotopes showed significant differences of the habitats resulting from the previous Cd-emission of metallurgy smelting non-ferrous metals. The winter grazing of the Tharandt Forest and the Harz mountains contained significantly more Cd than that of the Lower Flaming hills, the western Erzgebirge and the northern agrarian areas. The bark and the tips of conifer twigs, twigs of oak and mountain ash, bilberry and heather plants, i. e. perennial plants resp. parts of plants proved to be particularly rich in Cd. On an average, wild ruminants consume more Cd than domesticated ruminants, which do not consume parts of perennial plants. The rumen contents of all wild ruminants contained, with 0.20 to 0.25 mg/kg dry matter more Cd than could be expected from the content of the grazing. In the Cd-contaminated areas the amount of Cd in the rumen contents too showed the Cd-load. The kidneys, livers and the covering hair of a total of 172 head red deer, roes and mouflons reflected the Cd-load and the dependence of the Cd-level on the age. The Cd-concentration ascertained in the organs of the wild ruminants was compared with that of sheep and cattle. The, on an average, higher Cd-load of the wild ruminants was confirmed. The kidneys of wild ruminants older than five years should, as a general principle, not be eaten and neither should the livers of animals from Cd-contaminated biotopes. The limb defects of mouflons from Cd-contaminated areas are discussed in connection with Cd-induced secondary Cu-deficiency resp. Mn- and Zn-deficiency. A reference is made to further works.     

Potato germplasm collecting expedition to Mexico in 1997: Taxonomy and new germplasm resources

Wild potato (Solanum sect.Petota) germplasm has been collected in Mexico on nine major expeditions, as determined by 20 collections or more from each expedition currently at the United States potato genebank, the National Research Support Program-6 (NRSP-6). These have resulted in 609 accessions with good collection data. In addition, NRSP-6 has germplasm of approximately 90 other Mexican collections that are unspecific regarding date or place of collection. This expedition was funded to collect those remaining collections with no or little germplasm:Solanum clarum,S. xedinense, S. hintonii, S. hjertingii var.physaloides, S. leptosepalum, S. lesteri, S. macropilosum, S. xmichoacanum, S. xsambucinum, andS. stenophyllidium. In addition, some species and species groups (species groups indicated in parentheses) have unresolved taxonomic problems that needed clarification by additional field collections. These are (S. agrimonifolium and S.oxycarpum), (S. brachycarpum, S. guerreroense, S. hougasii, andS. iopetalum - theS. brachycarpum complex), (S. fendleri, S. papita, S. stoloniferum - theS. stoloniferum complex),S. leptosepalum, andS. macropilosum. We conducted a wild potato germplasm collecting expedition in Mexico from August 22 to October 31, 1997. Our 103 collections, 71 as germplasm collections, provide the first germplasm samples forS. hjertingii var.physaloides,S. leptosepalum, andS. macropilosum. They provide additional germplasm of the rare speciesS. clarum, S. xedinense, S. lesteri, S. xmichoacanum, S. xsambucinum, andS. stenophyllidium. We additionally gathered germplasm and field data to help resolve taxonomic difficulties inS. agrimonifolium andS. oxycarpum, theS. brachycarpum complex, and theS. stoloniferum complex.     

Management of concurrent patellar luxation and cranial cruciate ligament rupture using modified tibial plateau levelling

Objectives : To evaluate a novel surgery aimed at managing concurrent medial patellar luxation (MPL) and cranial cruciate ligament (CCL) ruptures in dogs weighing more than 30 kg. Methods : Tibial plateau levelling osteotomy (TPLO) and femoral trochleopasty were performed. The principal tibial fragment was laterally translated by 3 to 6 mm and was externally and abaxially rotated to create a wedge measuring 1·5 to 2·5 mm at the medial and cranial aspect and 1 to 3 mm at the medial and distal aspect of the tibial plateau fragment. The fragments were stabilised with a narrow TPLO plate. Results : Thirteen surgeries were performed in 12 dogs with a mean weight of 39·8 kg. The mean postoperative tibial plateau slope was 8·1°. Additional surgery was required in two cases, one due to failure of fixation and another due to screw breakage. The mean lameness score was 3·5 (out of 5) before surgery, 0·7 after 8 to 12 weeks, and 0·3 at final follow-up. Median follow-up was 1115 days (range, 270 to 2040 days). No patella luxated after surgery. Clinical Significance : MPL and CCL ruptures may be successfully managed by performing a TPLO and simultaneously altering the relationship of the principal and tibial plateau fragments during surgery.