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1.
The present work reports a characterization of mean wet weight and moisture, the lipid class and fatty acid (FA) composition from the total lipids (TL), of both culture and wild eggs of the cuttlefish, Sepia officinalis , throughout the embryonic development. Additionally, reproductive data, such as the number of spawnings, number and mean weight of eggs and duration of spawning period of cultured cuttlefish is provided. Both types of eggs were similar in mean wet weight, moisture content, TL content and lipid composition throughout embryonic development. Females from the cultured group spawned 13 times and laid 8654 eggs in 64 days, with a mean weight of 0.607 ± 0.179 g. A sex ratio of 1.57 (11♀ for 7♂) promoted an individual fecundity of 787 eggs/♀ (the biggest until now on our culture facilities), which might be related to increased bottom areas. The TL increased with day/stage of embryonic development ( P  < 0.05) only in the cultured egg group. However, no differences were found on TL between culture and wild eggs at the same day/stage ( P  > 0.05). Eggs displayed predominant levels of phosphatidylcholine, phosphatidylethanolamine (PE), cholesterol and triacylglycerol at the end of embryonic development. Polar and neutral lipids of both eggs groups remained consistently proportional (∼50% for each lipid fraction) and a significant increase ( P  < 0.05) was observed in phosphatidylserine, PE and free FA throughout the embryonic development. In either egg type and day, 16:0, 18:0, 20:5n-3 and 22:6n-3 accounted for approximately 70 g Kg−1 of all FA and saturated and n-3 totals seemed to have the same proportion in the cuttlefish eggs. The present results suggest that lipids are not used as energetic substrate but as structural components in cuttlefish egg.  相似文献   
2.
Acoustic survey data were used to estimate the abundance and distribution of age-0 walleye pollock and zooplankton near the Pribilof Islands, Bering Sea, nursery area at two time periods in two consecutive years: the beginning of August, and mid-September, of 1996 and 1997. The 1996 pollock year class ultimately produced a large adult cohort in the eastern Bering Sea, while the 1997 year class produced a below-average adult cohort. Acoustic densities of age-0 pollock were significantly lower in August – and declined more strongly from August to September – in 1997 than in 1996, indicating that the trend to adult cohort strength was already set by August. Diet composition analyses revealed that age-0 pollock ate a much higher proportion of euphausiids in 1997 than in 1996, despite lower acoustic abundance of euphausiids in 1997. We infer that in 1996, age-0 pollock experienced greater feeding success by August, with high concentrations of copepods available for smaller fish to consume, and high concentrations of euphausiids available for larger individuals. In 1997, age-0 pollock had lower body condition in August and may have been limited by the availability of small (<2 mm) copepods. Bioenergetic modeling of prey consumption did not indicate a likelihood that age-0 pollock would begin to deplete euphausiids until late August in 1996, and not at all between August and mid-September in 1997.  相似文献   
3.
Walleye pollock Theragra chalcogramma (pollock hereafter) is a key ecological and economic species in the eastern Bering Sea, yet detailed synthesis of the spatial and temporal patterns of pollock ichthyoplankton in this important region is lacking. This knowledge gap is particularly severe considering that egg and larval distribution are essential to reconstructing spawning locations and early life stages drift pathways. We used 19 yr of ichthyoplankton collections to determine the spatial and temporal patterns of egg and larval distribution. Generalized additive models (GAMs) identified two primary temporal pulses of pollock eggs, the first occurring from 20 February to 31 March and the second from 20 April to 20 May; larvae showed similar, but slightly lagged, pulses. Based on generalized cross‐validation and information theory, a GAM model that allowed for different seasonal patterns in egg density within three unique areas outperformed a GAM that assumed a single fixed seasonal pattern across the entire eastern Bering Sea. This ‘area‐dependent’ GAM predicted the highest densities of eggs (i.e., potential spawning locations) in three major areas of the eastern Bering Sea: near Bogoslof Island (February–April), north of Unimak Island and the Alaska Peninsula (March–April), and around the Pribilof Islands (April–August). Unique temporal patterns of egg density were observed for each area, suggesting that pollock spawning may be more spatially and temporally complex than previously assumed. Moreover, this work provides a valuable baseline of pollock spawning to which future changes, such as those resulting from climate variability, may be compared.  相似文献   
4.
Objective: To compare surgical times and perioperative complication rates of single portal access and 2-portal laparoscopic ovariectomy (LapOVE) in dogs using a bipolar vessel sealer/divider device, and to evaluate the performance of novice laparoscopists for right ovariectomy.
Study Design: Controlled clinical trial.
Animals: Female dogs (n=42).
Methods: Dogs were divided into groups: 1=single portal and 2=2 portal. LapOVE was performed using a 5 mm vessel sealer/divider device and a 10 mm operating laparoscope (Group 1) or a 5 mm laparoscope (Group 2). Dog characteristics (weight, body condition score, ovarian ligament fat score), operative time, and perioperative complication rate were compared between groups. Right ovariectomy duration was evaluated for 2 novice laparoscopists.
Results: No significant difference was found in mean total surgical time between group 1 (21.07 min/s) and group 2 (19.06 min/s). Factors significantly affecting times included body condition scores, ovarian ligament fat score, ovarian bleeding, and surgeon expertize. Minor complications (bleeding from ovaries or after splenic trauma) occurred and were similar in both groups. Bleeding was correlated to body condition score and ovarian ligament fat score. Interindividual differences were found among surgeons for right ovariectomy time.
Conclusions: Single portal access LapOVE using vessel sealer/divider device is feasible, safe, and does not significantly increase total surgical time in comparison with 2-portal approach. Laparoscopic skills may play a role in ability to perform single portal LapOVE.
Clinical Relevance: LapOVE can be performed using single portal access.  相似文献   
5.
Declines of Steller sea lion (Eumetopias jubatus) populations in the Aleutian Islands and Gulf of Alaska could be a consequence of physical oceanographic changes associated with the 1976–77 climate regime shift. Changes in ocean climate are hypothesized to have affected the quantity, quality, and accessibility of prey, which in turn may have affected the rates of birth and death of sea lions. Recent studies of the spatial and temporal variations in the ocean climate system of the North Pacific support this hypothesis. Ocean climate changes appear to have created adaptive opportunities for various species that are preyed upon by Steller sea lions at mid‐trophic levels. The east–west asymmetry of the oceanic response to climate forcing after 1976–77 is consistent with both the temporal aspect (populations decreased after the late 1970s) and the spatial aspect of the decline (western, but not eastern, sea lion populations decreased). These broad‐scale climate variations appear to be modulated by regionally sensitive biogeographic structures along the Aleutian Islands and Gulf of Alaska, which include a transition point from coastal to open‐ocean conditions at Samalga Pass westward along the Aleutian Islands. These transition points delineate distinct clusterings of different combinations of prey species, which are in turn correlated with differential population sizes and trajectories of Steller sea lions. Archaeological records spanning 4000 yr further indicate that sea lion populations have experienced major shifts in abundance in the past. Shifts in ocean climate are the most parsimonious underlying explanation for the broad suite of ecosystem changes that have been observed in the North Pacific Ocean in recent decades.  相似文献   
6.
A dog with traumatic monoplegia had a spinal cord lesion, identified using conventional magnetic resonance imaging. In addition, the intrathecal use of gadopentate dimeglumine allowed identification of two sites of cerebrospinal fluid leakage from the vertebral canal, supporting a diagnosis of brachial plexus avulsion.  相似文献   
7.
The os penis in the cat has not been described radiographically, as compared with the dog. However, a small linear bony radiopacity is sometimes detected in the perineal area of male cats. We hypothesized that the feline os penis might be visible on survey radiographs of the pelvis, and we aimed to investigate the frequency of its visualization using analog and computed radiography (CR) system. One hundred radiographs of the pelvis of 99 male cats were reviewed retrospectively (50 were obtained with a CR system and 50 with an analog system). Age, breed, neutering status, and reason for presentation were recorded, as well as the visualization of the os penis. An os penis was detected in 19/50 (38%) cats with CR and in eight of 50 (16%) cats with analog radiography; this difference was statistically significant. With CR, the median age of cats with a visible os penis was significantly higher than in cats where the os penis was not seen. In one cat with a visible os penis examined with CR and analog radiography, the os penis was only visible on CR images. The penile tissues were examined histopathologically in one cat and well‐differentiated bone was found but there were no pathologic findings detected in surrounding tissues. Thus, the os penis can be detected on radiographs of cats and this should not be mistaken for a pathologic finding such as urolithiasis or dystrophic mineralization.  相似文献   
8.
The effects of feeding three natural frozen diets, grass shrimp (Palaemonetes sp.), crayfish (Procambarus clarkii) and fish (Sardina pilchardus) and two semi‐humid artificial diets (based on fish or shrimp powder) to the cuttlefish, Sepia officinalis, were analysed. Growth rate and feeding rate [FR; % body weight (BW) day?1] and food conversions (FC, %) were determined. Cuttlefish fed shrimp grew larger (3.8% BW day?1) and had the highest FC, followed by those fed crayfish, and sardine. The highest FR was obtained for cuttlefish fed crayfish (10.5% BW day?1). Although both artificial diets were accepted, none produced growth. Digestive gland‐to‐body weight ratio (DG/BW ratio) was calculated for animals fed each diet. A positive correlation (r = 0.94) between cuttlefish ingestion FR and DG weight was obtained. Mortality occurred mainly during the last week, and some cannibalism occurred among cuttlefish fed artificial diets. Finally, lipid composition of diets, DG and mantle of each group were analysed. Sardine diet was characterized by high levels of triacylglycerol (TG), whereas the main difference between shrimp and crayfish was the higher n‐3/n‐6 ratio found in shrimp. Changes in the lipid composition of DG were related to diet, but did not correlate with growth data. A strong loss of TG in the DG of artificial diets groups was notable. No differences in mantle lipid composition among the natural diets were found, but artificial diet groups showed higher contents of neutral lipids in their mantle respect to natural diets. According to results obtained, crayfish (P. clarkii) could be used as an alternative prey for rearing S. officinalis compared with shrimp. Artificial diets showed the worst effects in growth and mortality as well as the stronger influence on DG and mantle lipid composition of cuttlefish.  相似文献   
9.
The most common cause of peripheral facial nerve paralysis in dogs, in the absence of otitis media, is thought to be idiopathic. Gadolinium-enhanced (Gd) magnetic resonance (MR) imaging has been used to study peripheral facial weakness in humans with a wide variety of disorders, including Bell's palsy, the clinical equivalent of idiopathic facial nerve paralysis in dogs. Gd-MR imaging may be useful to demonstrate abnormal enhancement of the intratemporal facial nerve. The aim of this study was to define the role of the Gd-MR imaging in dogs with idiopathic facial nerve paralysis, with regard to pattern of enhancement, and to search for prognostic information. Six dogs with peripheral facial nerve paralysis, followed between 2003 and 2005, were studied. Physical and neurologic examinations, as well as clinical tests, were performed, including routine hematology, serum biochemistry, thyroid screening, cerebrospinal fluid analysis, and MR imaging. The time interval between the onset of the clinical signs, the progress of the disease, and the final recovery was noted in each dog. The following four intratemporal segments of the facial nerve were analyzed: internal acoustic meatus, labyrinthine segment/geniculate ganglion, tympanic segment, and mastoid segment. Along its length, contrast enhancement was found in four dogs. In this group, contrast enhancement of the facial nerve was found in all segments of two dogs, in three segments of one dog, and in one segment of the other dog. In the four dogs with enhancement, one recovered completely in 8 weeks and three have not recovered completely. The two dogs without evidence of enhancement recovered completely in an average time of 4 weeks.  相似文献   
10.
Our aim was to characterize the magnetic resonance (MR) imaging features of canine disc extrusion accompanied by epidural hemorrhage or inflammation. We correlated the imaging characteristics of this type of disc extrusion in 46 dogs and compared these features with clinical signs and pathologic findings. Data from 50 control dogs with MR imaging features of a disc extrusion with no associated hemorrhage or inflammation, characterized by a T2‐hypointense extradural mass, were used for comparison of the relative location of the two types of lesions and prognosis. Disc extrusion causing epidural hemorrhage or inflammation is more common in the caudal aspect of the lumbar spine than disc extrusions that do not cause signs of hemorrhage or inflammation (P<0.05) in MR images. In dogs with disc extrusion and associated epidural hemorrhage or inflammation, there was no association between MR imaging features and signalment, the presence or absence of hemorrhage, or pathologic findings. The appearance of the lesion created by disc extrusion with epidural hemorrhage and inflammation encompasses a wide variety of imaging features, likely related to the duration of the hemorrhage and associated inflammatory changes. In 10 of 46 dogs these secondary changes masked identification of the disc extrusion itself in the MR images. An awareness of the variety of MR imaging features of disc extrusion accompanied by extradural hemorrhage or inflammation is important to avoid making an incorrect diagnosis and to facilitate a proper surgical approach. The prognosis of dogs with disc extrusion accompanied by hemorrhage or inflammation does not appear to be different than for dogs with disc extrusion and without imaging signs of epidural hemorrhage or inflammation.  相似文献   
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