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1.
Strips of rumen wall from bovine fetuses were incubated in an organ bath with prostaglandin F2 alpha (0.13 to 33.76 g/ml). The highest reactivity with a submaximal dose (17.03 g/ml) was observed in the period between 3.0 and 7.9 months of fetal age. A smaller response, but higher than in 1.0 to 2.9 months old fetuses, was observed in the 8.0 to 8.9 months fetuses. The period of the highest reactivity to prostaglandin F2 alpha coincides with the age of onset of papillary morphogenesis and the period of highest reactivity to autonomic and putative transmitter drugs.  相似文献   
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3.

Background

Chiari‐like malformation (CM) and syringomyelia (SM) cause a pain syndrome in Cavalier King Charles spaniels (CKCS). Clinical signs are not consistently apparent on neurologic examination, and owner reporting of signs provides vital clinical history. However, owner questionnaires for this disease are not well developed.

Objectives

To develop a tool to capture owner‐reported clinical signs for use in clinical trials and to compare owner‐reported signs with the presence of pain on neurologic examination and SM on magnetic resonance imaging (MRI).

Animals

Fifty client‐owned CKCS.

Methods

Owners completed a questionnaire and pain/scratch map. Each dog underwent a neurologic examination and craniocervical magnetic resonance imaging (MRI). Questionnaire responses were developed into scores, area of shading for pain/scratch maps was measured, and consistency of responses between these tools was assessed. Owner‐reported findings were compared with neurologic examination findings and presence and severity of SM on MRI.

Results

Thirty‐three dogs were symptomatic and 17 asymptomatic; 30 had SM. The most common sign of pain was crying out when lifted (n = 11). Extent of shaded areas on maps positively correlated with questionnaire scores for pain (r2 = 0.213, = 0.006) and scratch (r2 = 0.104, = 0.089). Owner‐reported findings were not significantly associated with presence or severity of SM or neurologic examination findings. Owner‐reported lateralization of signs was significantly associated with SM lateralization (< 0.0001).

Conclusions

The questionnaire and maps may be useful for clinical trials. Lack of association of owner‐reported signs with SM highlights our lack of understanding of the pathophysiology of pain in this disease.  相似文献   
4.
An imaging report is a vital communication tool between a radiologist and clinician. In a field where in‐person communication may not be readily available, it is imperative that the report clearly relays pertinent clinical information in a timely manner. The purpose of this observational study was to describe and compare opinions and expectations of small animal general practitioners, veterinary specialists, and veterinary radiologists regarding the imaging report. Online surveys were distributed, and data were collected from 202 veterinary clinicians and 123 veterinary radiologists. The majority (89%) of clinicians were satisfied with their imaging reports and stated that they read the radiology report as soon as it was available (92%). Just less than half (48%) of clinicians indicated it was standard of care that a board‐certified veterinary radiologist read all imaging studies. Radiologists and clinicians agreed that a clinical history (98% and 94%, respectively) and clinical question (82% and 68%, respectively) were needed to generate a good radiology report. Fifty‐five percent to 70% of clinicians prefer red bulleted reports, which included incidental findings (96%); while radiologists slightly favored prose reporting (37–46%). Clinicians found it helpful when additional imaging (86%), medical (71%), and surgical recommendations (73%) were made. About one‐third of specialists who had been in practice for >11 years thought they were better able to interpret imaging for their own specialty than the radiologist. Clinicians voiced discontentment with reports that were not completed in a timely manner or did not give a prioritized differential list. Further studies are warranted to provide a more in‐depth evaluation of veterinary radiology reporting structure and style.  相似文献   
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6.
Phenotypic variation in organisms depends on the genotype and the environmental constraints of the habitat that they exploit. Therefore, for marine species inhabiting contrasting aquatic conditions, it is expected to find covariation between the shape and its spatial distribution. We studied the morphology of the head and cephalic sensory canals of the eelpout Austrolycus depressiceps (4.5–22.5 cm TL) across its latitudinal distribution in South Pacific (45°S–55°S). Geometric morphometric analyses show that the shape varied from individuals with larger snout and an extended suborbital canal to individuals with shorter snouts and frontally compressed suborbital canal. There was size variation across the sampled populations, but that size does not have a clear latitudinal gradient. Only 8% of the shape variation relates to this size variation (allometry), represented by a decrease in the relative size of the eye, and a depression of the posterior margin of the head. There were spatial differences in the shape of the head, but these differences were probably caused by allometric effects. Additionally, 2 of the canals of the cephalic lateralis pores and the head shape showed modularity in its development. This study shows that the morphology of marine fish with a shallow distribution varies across distances of hundreds of kilometers (i.e., phenotypic modulation).  相似文献   
7.
The present study evaluated the effects of five bacterial isolates from the microalga Muriellopsis sp. on the microalgal biomass concentration (g/L), specific growth rate (K), photosynthetic quantum yield (QY), non‐photochemical quenching (NPQ), maximum relative electron transport rates (rETR max) and levels of nutritional components such as carbohydrates, lipids, proteins and carotenoids in Muriellopsis sp. cultivated in seawater under indoor and outdoor conditions. The bacterial strains were Microbacterium sp. Dom 1; Pseudomonas sp. Dom2; Microbacterium sp. Dom 3; Rhizobium sp. Dom 4; and Dietzia sp. Dom 5, as well as the Pseudoalteromonas sp. (SLP1), a bacterium known to promote the growth of microalgae. At the laboratory level, inoculation of the strains SLP1, Dom 1, Dom 3 and Dom 5 resulted in higher specific growth rates and biomass of the microalga. Subsequently, the best results were obtained with a combination of the selected bacterial strains (Dom1, Dom 3, Dom5 and SLP1) under outdoor culture conditions improved the biomass, proteins, carbohydrates and total carotenoids in 22.12%, 48.28%, 19,25% and 48.27%, respectively, compared to cultures without the incorporation of the selected bacteria (control), while no effects were observed on the photosynthetic parameters. Thus, it was demonstrated that positive associations of the selected bacterial strains played an important role in the production of Muriellopsis sp. acclimatized to grow in seawater. This is of crucial importance, especially in desert areas, where solar radiation is high and freshwater is a limited resource.  相似文献   
8.
Effects of exogenous (water temperature) and endogenous (lipid droplet adherence) factors were experimentally tested on early survival of southern hake Merluccius australis reared under controlled conditions. Experiments to determine the effect of temperature (10, 12 and 14 °C) on larval growth rates and yolk-sac absorption rates of unfed southern hake were carried out under laboratory conditions. There was no significant differences in growth rates at the temperature range tested (ANCOVA, F = 0.164, p > 0.25), but yolk-sac absorption rates and mortality increased with temperature (ANCOVA, F = 53.84, p < 0.001). A high percentage (between 31 and 81%) of hake eggs showed a lipid droplet not adhered (i.e., freely moving in the yolk, and not located in the posteriormost portion of the yolk-sac). In a second experiment, fed southern hake larvae with the lipid droplet not adhered during embryonic development did not survive after yolk-sac absorption. This study provides the first data on the influence of the lipid droplet absorption on larval survival of cultured hake, and can be used as an early indication of the quality of the batch.  相似文献   
9.
The effects of straws volume, cryoprotectants and thawing temperatures were evaluated on the sperm quality of cachama blanca Piaractus brachypomus (Cuvier), an important Colombian fish species. Sexually mature fish were induced to ovulation or spermiation with a carp pituitary extract. A pool of suitable sperm samples was diluted in glucose, egg yolk, dimethyl sulphoxide (DMSO‐10%), methanol (MET‐10%) or ethylene glycol (ETG‐5%) and packed in 0.5, 2.5 or 5.0 mL straws and frozen in nitrogen vapour. The thawing process was performed in a 35 or an 80 °C water bath. The fertility was evaluated after 6 h post fertilization. The highest motility percentage (33 ± 3%) was observed with sperm cryopreserved with DMSO, packed in 5 mL straws and thawed at 35 °C. The treatments with DMSO and MET packed in 0.5 and 5.0 mL straws and thawed at 35 °C showed the highest fertility (higher than 71%) and the lowest fertility was obtained with MET‐2.5 mL (9 ± 5%). In all the treatments, a significant decrease in the sperm quality was observed at 80 °C. Sperm cryopreserved with DMSO‐10% or MET‐10%, packed in 2.5 or 5.0 mL straws are suitable to achieve acceptable fertilization and to fertilize high amounts of eggs.  相似文献   
10.
The stable production of high‐quality fry in marine aquaculture is still hampered by unpredictable mortality caused by infectious diseases during larval rearing. Consequently, the development of new biocontrol agents is crucial for a viable aquaculture industry. The bacterial energy storage compound poly‐β‐hydroxybutyrate (PHB) has been shown to exhibit beneficial properties on aquatic organisms such as enhanced survival, growth, disease resistance and a controlling effect on the gastrointestinal microbiota. However, the effect of PHB on the developing immune system of fish larvae has so far not been investigated. In this study, the effect of feeding PHB‐enriched Artemia nauplii on survival, growth and immune response in European sea bass (Dicentrarchus labrax) postlarvae was examined. Amorphous PHB was administered to 28‐day‐old sea bass postlarvae over a period of 10 days. The survival and growth performance were monitored, and the expression of 29 genes involved in immunity, growth, metabolism and stress‐response was measured. While the expression of the insulin‐like growth factor 1 (igf1), an indicator of relative growth, was upregulated in response to feeding PHB, the larval survival and growth performance remained unaffected. After 10 days of PHB treatment, the expression of the antimicrobial peptides dicentracin (dic) and hepcidin (hep) as well as mhc class IIa and mhc class IIb was elevated in the PHB fed postlarvae. This indicates that PHB is capable of stimulating the immune system of fish early life stages, which may be the cause of the increased resistance to diseases and robustness observed in previous studies.  相似文献   
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