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排序方式: 共有416条查询结果,搜索用时 15 毫秒
101.
McGreevy PD Costa F Della Torre P Thomson PC Nicholas FW 《Journal of veterinary medical education》2005,32(4):551-554
This online database uses a search facility that allows users to select from the 180 recognized dog breeds in Australia and find out which ones are prone to the more than 500 inherited disorders on record. It was developed in consultation with a number of supporting organizations, including the local breeders' governing body and animal-welfare groups, as well as owners. It is hoped that, although primarily for veterinary education, the Web site will increase awareness among breeders and may encourage them to adopt breeding programs that decrease the occurrence of the most prevalent disorders. 相似文献
102.
Nuñez E Steffey EP Ocampo L Rodriguez A Garcia AA 《American journal of veterinary research》2004,65(10):1342-1346
OBJECTIVE: To quantitate the dose- and time-related effects of IV administration of xylazine and detomidine on urine characteristics in horses deprived of feed and water. ANIMALS: 6 horses. PROCEDURE: Feed and water were withheld for 24 hours followed by i.v. administration of saline (0.9% NaCI) solution, xylazine (0.5 or 1.0 mg/kg), or detomidine (0.03 mg/kg). Horses were treated 4 times, each time with a different protocol. Following treatment, urine and blood samples were obtained at 15, 30, 60, 120, and 180 minutes. Blood samples were analyzed for PCV and serum concentrations of total plasma solids, sodium, and potassium. Urine samples were analyzed for pH and concentrations of glucose, proteins, sodium, and potassium. RESULTS: Baseline (before treatment) urine flow was 0.30 +/- 0.03 mL/kg/h and did not significantly change after treatment with saline solution and low-dose xylazine but transiently increased by 1 hour after treatment with high-dose xylazine or detomidine. Total urine output at 2 hours following treatment was 312 +/- 101 mL versus 4,845 +/- 272 mL for saline solution and detomidine, respectively. Absolute values of urine concentrations of sodium and potassium also variably increased following xylazine and detomidine administration. CONCLUSIONS AND CLINICAL RELEVANCE: Xylazine and detomidine administration in horses deprived of feed and water causes transient increases in urine volume and loss of sodium and potassium. Increase in urine flow is directly related to dose and type of alpha2-adrenergic receptor agonist. Dehydration in horses may be exacerbated by concurrent administration of alpha2-adrenergic receptor agonists. 相似文献
103.
104.
Federico Márquez Jorgelina Robledo Gabriela Escati Peñaloza Silvina Van der Molen 《Fisheries Research》2010,101(1-2):127-131
The striped clam (Ameghinomya antiqua (King, 1832)) metapopulation of the San José Gulf is a good model for phenotypic stocks studies based on the shell shape variation in different fishing grounds. These sites show differences in circulation, tidal currents, coastal topography, and bathymetry. Furthermore, it is known that the diverse environments produce differences in the growth rate of this species. In the current work, we study the shell shape changes in the striped clam from different fishing grounds of the San José Gulf through geometric morphometrics methods. Outlines and landmarks analyses were successful to determinate the provenance of the individuals, with almost the 90% of correct assignations for the most of the fishing grounds. The different methodologies showed variations in diverse morphological traits, and as a result different patterns of the shell shape among localities were evidenced. Moreover, each site presented a typical shell shape. Our results showed that the geometric morphometrics methods are powerful tools to identify and separate intra-specific groups. This approach is applicable to other exploited species with subtle shape variations. 相似文献
105.
Genaro M. Soto-Zarazúa Enrique Rico-García Rosalía Ocampo R. G. Guevara-González Gilberto Herrera-Ruiz 《Aquaculture International》2010,18(3):379-391
In high-fish-density aquaculture systems, tilapia producers are compelled to provide 100% of food required to obtain profitable
growth rates. It is well known that fish have a low food conversion rate and feeding represents the most important expenditure,
approximately 40% of total production cost. Therefore, precise quantities of food should be provided to avoid water pollution
and economic losses due to food waste when water conditions are inadequate for fish feeding. A way to control food provisions
in this work was determined by the conditions of temperature, dissolved oxygen, fish age, and body weight, since these variables
have a direct effect on fish metabolism and growth. Thus, a change in metabolism is reflected in a modification of energy
requirements and, as a consequence, in variations of food consumption. In this work, a new feeder with fuzzy-logic control
algorithms is proposed for fish feeding; this technique allows farmer knowledge to be taken into account in a series of if–then-type
rules. To define these rules the temperature and dissolve oxygen were considered in order to provide precise food quantities.
The results show minimal differences in growth (P > 0.05) between treatments, important food saving of 29.12% (equivalent to 105.3 kg), and lower water pollution (reduced
water dissolved solids and ammonium components) compared with timed feeders. This system provides an important contribution
to sustainability of intensive aquaculture systems, increasing productivity and profitability, and optimizing water use. 相似文献
106.
Chiara De Gennaro Enzo Vettorato Federico Corletto 《The Canadian veterinary journal. La revue veterinaire canadienne》2022,63(1):67
This retrospective study assessed the effect of an intraoral bilateral maxillary nerve block in dogs undergoing surgery for brachycephalic obstructive airway syndrome (BOAS). Records of dogs that underwent BOAS surgery were retrieved. Cases were assigned to Group B or C if a preoperative bilateral maxillary nerve block was performed or not. Type and dose of local anesthetic, inhalant anesthetic minimum alveolar concentration multiples, intraoperative fentanyl and injectable anesthetic use, prevalence of intraoperative hypotension or bradycardia, and postoperative opioids administration, were compared between groups. Sixty-seven cases met the inclusion criteria: 33 were assigned to Group B and 34 to Group C. In Group C, 18 dogs required intraoperative fentanyl (P = 0.005), and 12 needed injectable anesthetic top-ups (P = 0.006). Hypotension, or bradycardia, were not different between groups. Bilateral maxillary nerve block reduces intraoperative fentanyl and injectable anesthetic requirement in dogs undergoing BOAS surgery. 相似文献
107.
108.
The Potential Use of Mangrove Forests as Nitrogen Sinks of Shrimp Aquaculture Pond Effluents: The Role of Denitrification 总被引:4,自引:0,他引:4
Victor H. Rivera-Monroy Luis A. Torres Nixon Bahamon Federico Newmark Robert R. Twilley 《Journal of the World Aquaculture Society》1999,30(1):12-25
A generalized nitrogen budget was constructed to evaluate the potential role of mangrove sediments as a sink for dissolved inorganic nitrogen (DIN) in shrimp pond effluents. DIN concentrations were measured in pond effluents from three semi-intensive shrimp ponds along the Caribbean coast of Colombia between 1994–1995. Mean NH4 + concentrations in the discharge water for all farms were significantly higher (67 × 12 μg/L) than in the adjacent estuaries (33 × 8 μg/L). Average NH4 + concentrations in the pond discharge over all growout cycles were similar, representing an approximate doubling in relation to estuarine water concentrations. In contrast, NO2 - + NO3 - concentrations were similar in both pond effluent and estuarine waters. Dissolved inorganic nitrogen loading of the ponds was similar. The estimated reduction of DIN in pond effluents by preliminary diversion of outflow to mangrove wetlands rather than directly to estuarine waters would be × 190 mg N/m2 per d. Based on this nitrogen loss and depending upon the enrichment rate, between 0.04 to 0.12 ha of mangrove forest is required to completely remove the DIN load from effluents produced by a 1-ha pond. 相似文献
109.
Federico Soria-Gálvez DVM Francisco Miguel Sánchez-Margallo DVM PhD Idoia Díaz -Güemes Martín-Portugus DVM Francisco Javier Hernández-Hernández MD PhD Luis Javier Ezquerra-Calvo DVM PhD Jesus Usón-Gargallo DVM PhD 《Veterinary radiology & ultrasound》2002,43(5):465-471
This work reports the use of laparoscopic-transducer sonography for the examination of the urinary system in a swine model. Animals underwent a two-phase study. In the first phase, the urinary system was examined using laparoscopic sonography. In the second a partial ureteral obstruction was induced, and sonographic changes were recorded and evaluated. Sonography was used to evaluate kidneys, ureters, and bladder. Anatomic structures were evaluated and the following pathological findings were identified: renal cysts, one polycystic kidney, dilation of the renal pelvis, hydronephrosis, and one perirenal pseudocyst. Where necessary, contrast digital fluoroscopy (excretory urography and retrograde ureteropyelography) was also performed. Laparoscopic sonography mainly is used for evaluation prior to laparoscopic surgery to guide decisions relating to surgery. The quality of the images obtained laparoscopically is superior to that of percutaneous or transabdominal images, because artifacts are reduced and the contact surface of the transducer is placed directly over the study area. Laparoscopic sonography proved highly effective for studying renal and ureteral disorders prior to minimally invasive surgery. 相似文献
110.
Romano Dallai Vittoria Cavallo Luigi Federico Falso Pietro Paolo Fanciulli 《Pedobiologia》2000,44(3-4)
The fine structure of the male reproductive system of Allacma fusca (L.) is described. The system consists of testes, deferent ducts, seminal vesicles, ejaculatory duct and accessory glands. The nature of each part is established. Secretions from the seminal vesicles are stored in the lumen of these organs, then flow into the ejaculatory duct and are used to produce spermatophores. The epithelium of this tract has secretory activity and osmoregulatory function. Secretions and spermatozoa are stored into two distinct parts of the ejaculatory duct, divided by a transverse cuticular septum. 相似文献