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Jaw Deformities (jaw + deformity)

Distribution by Scientific Domains

Earth and Environmental Science	100%

Selected Abstracts

Skeletal development and deformities in cultured larval and juvenile seven-band grouper, Epinephelus septemfasciatus (Thunberg)

AQUACULTURE RESEARCH, Issue 2 2007
Naoki Nagano
Abstract The seven-band grouper, Epinephelus septemfasciatus (Thunberg), is currently recognized as a potential new species for aquaculture in Japan. This study describes normal and abnormal skeletal development of the jaw and vertebrae in cultured larvae and early juveniles of E. septemfasciatus. The ontogenetic stages at which skeletal deformities of jaw and vertebra developed were also described for this species. Osteological observations were made using a clearing and staining method for larvae and soft X-ray photographs for juveniles. A high incidence of skeletal deformities was observed in the jaws and vertebral column during the larval and juvenile stages. Most of the jaw deformities were explained by an abnormal maxilla curvature. Jaw deformities were visually evident from flexion stage after ossification of the deformed elements. Deformities in the vertebral column (mostly lordosis) were observed from the post-larval stage and became more evident as growth proceeded. The lordosis generally occurred on the positions of the 8,11th vertebra. These types of deformities are compared with those of other species, and possible causative factors of the skeletal deformities are discussed. [source]

Randomized clinical field trial of a bacterial kidney disease vaccine in Atlantic salmon, Salmo salar L.

JOURNAL OF FISH DISEASES, Issue 7 2010
T A Burnley
Abstract A randomized, blinded clinical trial was performed to assess the relative effectiveness of five commercial and one experimental vaccine in a population of farmed fish experiencing a bacterial kidney disease (BKD) outbreak that occurred in one study cage that was part of a larger clinical field trial. A total of 6000 uniquely identified Atlantic salmon S1 presmolts were randomly assigned to vaccine groups in the hatchery and transferred to a commercial marine aquaculture site. Repeated sampling events to evaluate growth, inherent physical conditions and health status were carried out over the entire production cycle. During the second summer at sea, the study cage developed an outbreak of BKD that lasted approximately 240 days. The effectiveness of the selected vaccines was evaluated using survival analysis methods. The sole vaccine group offering protection for BKD was found to significantly decrease the hazard of dying (hazard ratio, HR = 0.68, P = 0.018) during the outbreak, compared to the industry standard, vaccine group. Additionally, during the outbreak, fish with a shortened operculum had a significantly decreased hazard (HR = 0.38, P = 0.033) compared to those fish with a normal operculum, while fish with jaw deformities had a significantly increased hazard (HR = 2.55, P = 0.001) compared to fish with normal jaw status. [source]

Teratogenicity of elevated egg incubation temperature and egg vitamin A status in Atlantic salmon, Salmo salar L.

JOURNAL OF FISH DISEASES, Issue 4 2004
R Ørnsrud
Abstract The present study was undertaken to investigate the possibility that high egg vitamin A (VA) status in combination with elevated egg incubation temperatures may cause deformities in Atlantic salmon, Salmo salar L. Egg batches selected for their total VA concentration were exposed to low (normal, 8 °C) or elevated (14 °C) egg incubation temperatures. Temperature was the main factor causing bone deformities such as warped gill opercula, fin and jaw deformities, but not for the development of spinal deformities where all groups displayed a ,baseline' occurrence of mild deformity (decreased vertebral size in the cephalic region) and no systematic variation in the occurrence of serious spinal deformities (fused vertebrae). A possible effect of egg incubation temperature fluctuation was found for the groups reared at low temperatures. An indication of a negative effect of elevated egg VA status for the development of organ deformities such as missing septum transversum and situs inversus was found in addition to temperature effects, however, no firm conclusions could be drawn from the present data. The phenotypes for temperature-induced deformities resembled the phenotype of VA-induced deformities, but no clear conclusions on the causality of the deformities found in the present study could be drawn. Egg incubation temperatures, both absolute temperature and temperature variations, should therefore be strictly controlled. [source]

Influence of Water Temperature on Morphological Deformities in Cultured Larvae of Japanese Eel, Anguilla japonica, at Completion of Yolk Resorption

JOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 6 2008
Tadahide Kurokawa
The occurrence of morphological deformities under different rearing water temperatures (18, 20, 22, 24, 26, 28, and 30 C) was examined in Japanese eel larvae. The rates of hatching and survival until yolk resorption at 22,26 C were higher than those at other water temperatures. Fertilized eggs never hatched at 18 and 30 C. The rates of occurrence of abnormal larvae reared at the water temperatures 24,28 C were lower than those at 20 or 22 C. Pericardial edema and lower jaw deformities occurred most frequently at lower temperatures (20 and 22 C). In contrast, the incubation temperature did not significantly affect the relative frequency of some neurocranial deformities and of spinal curvature. These results imply that the optimal temperatures for rearing Japanese eel eggs and embryos are 24,26 C from the viewpoints of survival and deformity. [source]