Radioisotope and stable isotope ratios (Δ14C, δ15N) suggest larval lamprey growth is dependent on both fresh and aged organic matter in streams     

Thomas M. Evans  Amber R. Bellamy  James E. Bauer 《Ecology of Freshwater Fish》2019,28(3):365-375

Lampreys have a complex life cycle which includes a multi‐year infaunal larval stage (ammocoete). Gut content analysis has generally identified detritus (i.e., unidentifiable organic matter) as the major dietary component to ammocoetes, though algae can also be important. However, gut content preserves only a snapshot of the animal's diet and does not reflect assimilated material. In order to better characterise the nutritional sources supporting ammocoete growth, we analysed ammocoete body tissue and potential dietary sources at two streams using natural Δ¹⁴C and δ¹⁵N to estimate time‐integrated nutritional support. Bayesian isotope mixing models revealed differences in the importance of sources supporting ammocoetes between sites. Ammocoetes from a stream in a mixed land usage area (~50% agriculture, ~40% forest and ~10% developed) were primarily supported (mean: ~50%) by fresh terrestrial organic matter but were also supported by substantial contributions (mean: ~30%) by aged organic matter (AOM) and autochthonous material (algae; mean ~20%). In a predominantly forested (~90%) headwater stream, different modelling scenarios (uninformed or informed priors) suggested that algal support of ammocoete nutrition ranged from 7% to 45%. However, the model relying on informed priors developed from gut content analysis produced the low estimates, suggesting these were more reliable. When algae were a minor component of the nutrition at the forested site, ammocoetes were highly dependent on AOM (83 ± 26%; mean ± SD). Based on these findings, ammocoete growth and development are predicted to be strongly influenced by both land use and the availability of allochthonous and autochthonous materials of varying ages within streams.  相似文献   

ENDOTOXAEMIA: RECENT ADVANCES IN PATHOPHYSIOLOGY AND TREATMENT     

James N.  Moore 《Veterinary anaesthesia and analgesia》1994,21(2):77-81

  相似文献   

MAGNETIC RESONANCE, ULTRASOUND AND HISTOPATHOLOGIC CORRELATION OF ACUTE AND HEALING EQUINE TENDON INJURIES     

Jeffrey R.  Crass  MD  Ronald L.  Genovese  VMD  James A.  Render  DVM  Errol M.  Bellon  MD 《Veterinary radiology & ultrasound》1992,33(4):206-216

Ultrasonography and MRI have become valuable tools for imaging of tendon injuries. The current study examines the histopathologic basis for the imaging abnormalities. Five injured equine forelimbs and two normal contralateral limbs were studied with high resolution real time ultrasound and MRI. Histologic sections were made and correlated with the diagnostic images. All lesions were readily seen by both modalities. Lesions characterized by hemorrhage, edma, and cellular infiltration were sonolucent on ultrasound and bright on MRI images. MRI returned to normal as fibrogenesis ensued. Ultrasound images remained abnormal until fibrillar reallgnment occured with completion of the healing process. High resolution real time ultrasound and MRI both accurately reflect the tissue abnormalities in acute tendon injuries. The injured horse does appear to be an effective model for correlative imaging studies of tendon injuries.  相似文献   

Beef feedlot industry.     

James Mintert 《Veterinary Clinics of North America: Food Animal Practice》2003,19(2):387-395

The United States cattle feeding sector has changed dramatically over time. Movement from an industry largely populated by farmer feeders using livestock to market their grain production to an industry composed of large, specialized, commercial cattle feeding firms has occurred since the end of World War II. Moreover, the industry also shifted geographically, moving away from the Corn Belt to the Plains as farmer feeders exited the industry. Today, the 10 largest firms in the industry likely market 22% to as much as 29% of all fed cattle produced in the United States. The shift in industry structure was at least partially motivated by the advent of improved technology. Successful implementation of rapidly evolving technology often required more intense, specialized management (and in some cases, larger operations) than was available in many farmer feeder operations. The ongoing shift away from live-weight pricing of fed cattle toward grid-based pricing could increase the need for specialized management yet again, encouraging even more industry consolidation in the future.  相似文献   

ULTRASOUND CORNER BLADDER WALL MASS EFFECT CAUSED BY THE INTRAMURAL PORTION OF THE CANINE URETER     

James P.  Douglass  DVM  MS 《Veterinary radiology & ultrasound》1993,34(2):107-107

  相似文献   

The Effect of Diet on the Biochemical Composition of Juvenile Artemia: Potential Formulations for Rock Lobster Aquaculture     

Matthew M.  Nelson Ben D.  Mooney Peter D.  Nichols Charles E  Phleger Greg G.  Smith Piers  Hart Arthur J.  Ritar 《Journal of the World Aquaculture Society》2002,33(2):146-157

The lipid class and fatty acid (FA) composition of juvenile Artemia fed continuously on four diets—the microalga Tetraselmis suecica , a mix of oat bran-wheat germ-lecithin (OWL), OwL-eicosapentaenoic acid (EPA), and OWL-EPA-arachidonic acid (AA)—were examined over a 9-d experiment in an attempt to approximate the FA profile of phyllosoma larvae of wild southern rock lobster Jasus edwardrii . The main difference in lipid class composition of Artemia fed the four diets was the relative level of polar lipid (PL) and triacylglycerol (TAG). By day 9, the algal-fed Artemia were highest in PL (95% of total lipid) and lowest in TAG (2%), whereas the remaining diets resulted in Artemia with 16–30% PL and 41–82% TAG. After 2 d, the relative FA composition of all Artemia treatments closely reflected those of the diets, with no marked change after further feeding (to day 9). In terms of the content of essential polyunsaturated fatty acids (PUFA), by day 5 Artemia fed: 1) with the algal diet contained 7 mg/g FA dry mass (0.3% DHA, 6.3% EPA, 3.4% AA of total FA); 2) with the OWL diet contained 3 mg/g (0.3% DHA, 0.9% EPA, 0.7% AA); 3) with the OWL-EPA diet contained 55 mg/g (6.2% DHA, 11.6% EPA, 1.1% AA); and 4) with the OWL-EPA-AA contained 83 mg/g (3.8% DHA, 7.5% EPA, 17.4% AA). The PUFA profiles of Artemia using the OWL-oil diets were similar to wild rock lobster phyllmmata, although levels of doco-sahexaenoic acid (DHA) were lower (10% DHA) than in J. edwardsii larvae. On the basis of PUFA composition data alone, the results suggest the suitability of the OWL-oil mixed diets for consideration for feeding to Artemia used in the culture of southern rock lobster larvae, particularly if the level of DHA can be further enhanced.  相似文献   

Artificial Spawning of Tilapia Eggs1     

James M. Myers  William K. Hershberger 《Journal of the World Aquaculture Society》1991,22(2):77-82

A stripspawning methodology was evaluated for tilapia (oreochromid) species. This technique achieved an average hatching success of 68.6 ± 3.6% (N= 31). Female fecundity and spawning frequency were dependant on both genetical and husbandry factors. Egg yields for Oreochromis niloticus, O. mossambicus, and O. niloticus±O. mossambicus hybrids averaged 4.54, 10.86 and 10.36 eggs/g female/spawn, respectively. Female broodstock that were adapted to an intensive spawning regime exhibited a significant increase in fecundity. Additionally, egg survival was not affected by hydration for up to 15 minutes prior to fertilization. Results suggest that the strip spawning of tilapia species may be an efficient method of providing viable gametes for hatchery purposes.  相似文献   

RADIOGRAPHIC DIAGNOSIS     

Ronald D.  Hodges  DVM  Russell L.  Tucker  DVM  James J.  Brace  DVM 《Veterinary radiology & ultrasound》1993,34(4):249-252

  相似文献   

RADIOGRAPHIC FINDINGS OF CANINE DYSAUTONOMIA IN TWENTY-FOUR DOGS     

David A.  Detweiler  David S.  Biller  DVM  James J.  Hoskinson  DVM  Kenneth R.  Harkin  DVM 《Veterinary radiology & ultrasound》2001,42(2):108-112

Canine dysautonomia is an idiopathic condition resulting in loss of autonomic nervous system function. Recently, the prevalence of dogs diagnosed with dysautonomia in the mid-western United States has increased. In this study the medical records and radiographic findings in 24 dogs with dysautonomia were reviewed. A diagnosis of dysautonomia was made in 17 (71%) of the dogs in this study by postmortem examination, the remaining 7 (29%) dogs were diagnosed pharmacologically. The radiographic findings supportive of dysautonomia include aspiration pneumonia, megaesophagus, or a distended stomach, small bowel, or urinary bladder. In some instances, the disease radiographically mimicked other disorders of the gastrointestinal tract, including mechanical obstruction.  相似文献   

What Is Your Diagnosis?     

Meinkoth JH  Cowell RL  Cowell AK 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1996,25(2):48-50

  相似文献