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131.
Weaning of beef calves is usually done abruptly and early compared to the natural weaning of the species, and is associated with simultaneous exposure of calves to a range of social and environmental stressors. Behavioural and physiological responses to weaning indicate detrimental effects on the welfare of these animals. The development and assessment of weaning methods aiming at reducing or avoiding this problem must be supported by scientific knowledge of the morphological, physiological and psychological mechanisms involved in the establishment, maintenance and braking of the cow-calf bond. Solutions also depend on the understanding of the various stressors associated with weaning, among which are the change in diet, cessation of nursing, separation from the dam, the change to a new spatial environment and the need for social reorganization following removal of the adults from the group. This review discusses these issues and assesses the effectiveness of the methods so far proposed for improving the welfare of beef calves during the weaning period. 相似文献
132.
Beltrán PK Gutiérrez-Ortega A Puebla-Pérez AM Gutiérrez-Pabello JA Flores-Valdez MA Hernández-Gutiérrez R Martínez-Velázquez M Alvarez AH 《Veterinary journal (London, England : 1997)》2011,190(1):181-183
This study combines two methodologies - vector expression of a genomic library and proteomics - to identify immunogenic proteins of Mycobacterium bovis. Immunization of BALB/c mice with a plasmid DNA pool from the library, containing approximately 8000 clones, induced a humoral response that facilitated the detection of 12 antigenic proteins by Western blotting. Two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and mass spectrometry identified four proteins (Cpn60-1, HSP70, EF-Tu, and AdoHcyase). Such genomic immunization offers the possibility of in vivo screening of potential candidate M. bovis antigens. 相似文献
133.
Camargo JB Steagall PV Minto BW Lorena SE Mori ES Luna SP 《Veterinary anaesthesia and analgesia》2011,38(3):252-259
ObjectiveTo compare the post-operative analgesic effects of butorphanol or firocoxib in dogs undergoing ovariohysterectomy.Study designProspective, randomized, blinded, clinical trial.AnimalsTwenty-five dogs >1 year of age.MethodsDogs received acepromazine intramuscularly (IM), 0.05 mg kg?1 and either butorphanol IM, 0.2 mg kg?1 (BG, n = 12) or firocoxib orally (PO), 5 mg kg?1 (FG, n = 13), approximately 30 minutes before induction of anesthesia with propofol. Anesthesia was maintained with isoflurane. Ovariohysterectomy was performed by the same surgeon. Pain scores using the dynamic and interactive visual analog scale (DIVAS) were performed before and at 1, 2, 3, 4, 6, 8 and 20 hours after the end of surgery by one observer, blinded to the treatment. Rescue analgesia was provided with morphine (0.5 mg kg?1) IM and firocoxib, 5 mg kg?1 (BG only) PO if DIVAS > 50. Groups were compared using paired t-tests and Fisher’s exact test (p < 0.05). Data are presented as mean ± SD.ResultsThe BG required significantly less propofol (BG: 2.6 ± 0.59 mg kg?1; FG: 5.39 ± 0.7 mg kg?1) (p < 0.05) but the anesthesia time was longer (BG: 14 ± 6, FG: 10 ± 4 minutes). There were no differences for body weight (BG: 7.9 ± 5.0, FG: 11.5 ± 4.6 kg), sedation scores, and surgery and extubation times (BG: 10 ± 2, 8 ± 5 minutes; FG: 9 ± 3, 8 ± 4 minutes, respectively) (p > 0.05). The FG had significantly lower pain scores than the BG at 1, 2 and 3 hours following surgery (p < 0.05). Rescue analgesia was administered to 11/12 (92%) and 2/13 (15%) dogs in the BG and FG, respectively (p < 0.05).Conclusion and clinical relevanceFirocoxib produced better post-operative analgesia than butorphanol. Firocoxib may be used as part of a multimodal analgesia protocol but may not be effective as a sole analgesic. 相似文献
134.
Alfredo Gravina José Cataldo Giuliana Gambetta Elisa Pardo Cecilia Fornero Sebastián Galiger Rodolfo Pienika 《Scientia Horticulturae》2011
Peel damage originated by wind is the main abiotic cause of citrus fruit discards for export in Uruguay. Natural windbreaks such as Eucalyptus and Casuarinas have not been effective in reducing it. This research was carried out during three years in a citrus orchard situated in the coastal plain of Uruguay (35° SL). The purpose of this work was to study wind climate inside the orchard, fruit seasonal sensitivity, basal leaf effect on the onset and evolution of peel damage, and the efficiency of artificial windbreaks to reduce fruit discard of ‘Ellendale’ tangor. Average wind velocity in the orchard did not exceed 5 m s−1. First peel scars were evident two weeks after petal fall and damaged fruit percentage importantly increased during the first stage of fruit growth. Low energy vortexes caused almost permanent friction between basal leaves and the developing fruitlets growing in their axil. Removal of the basal leaf decreased significantly wind damaged fruit. Natural wind flow modification through the use of semi-porous artificial windbreak nets (5 cm by 10 cm mesh) modified low energy vortexes and increased significantly the percentage of export quality fruit. We conclude that this type of net is more efficient than natural windbreaks or classical nets to reduce wind damage in citrus fruit. 相似文献
135.
Cronan DS Van Andel TH Heath GR Dinkelman MG Bennett RH Bukry D Charleston S Kaneps A Rodolfo KS Yeats RS 《Science (New York, N.Y.)》1972,175(4017):61-63
Iron-rich sediments chemically similar to those forming at present on the crest of the East Pacific Rise have been found just above basement at widely separated drill sites in the eastern equatorial Pacific, including three sites of Leg 16 of the Deep Sea Drilling Project. These sediments were probably formed when the basement was at the crest of this rise and have moved to their present location as a result of sea-floor spreading. 相似文献
136.
Frédérique Eyrolle Olivier Radakovitch Patrick Raimbault Sabine Charmasson Christelle Antonelli Emmanuelle Ferrand Dominique Aubert Guillaume Raccasi Stéphanie Jacquet Rodolfo Gurriaran 《Journal of Soils and Sediments》2012,12(9):1479-1495
Purpose
Almost 20 nuclear reactors are situated along the Rh?ne valley, representing Europe??s largest concentration of nuclear power plants. The fate of suspended sediments and natural and artificial particle-bound radionuclides in relation to extreme hydrological events was assessed at the lower course of the Rh?ne River, which provides the main source of water and sediment inputs to the northwestern Mediterranean Sea.Materials and methods
We sampled water at a high frequency over the period 2001?C2008 and measured suspended particulate matter (SPM) loads and particle-bound natural and artificial radionuclide concentrations at the SORA observatory station in Arles, France. We monitored various hydrological events (either natural or anthropogenic origin) and characterize their influence on concentrations and fluxes.Results and discussion
The relationship between SPM concentration and the very wide range of water discharges did not differ significantly from previous periods, indicating no significant shift in the average sediment delivery over the last 20?years. Unexpected hydrological events of anthropogenic origin, in particular those associated with flushing of reservoirs that are generally not captured by sampling strategies, were recorded and were shown to transfer significant additional sediment and associated contaminants towards the marine environment. Concentrations of anthropogenic radionuclides associated with sediment (i.e., 137Cs, 60Co, 54Mn, 110mAg, and Pu isotopes) varied over two to three orders of magnitude during periods of low and moderate flow due to variations in the liquid release from nuclear facilities. Except for Pu isotopes, the concentrations of the various particle-bound radionuclides generally showed a decreasing trend with increasing discharge, revealing the geochemical or anthropogenic background values, and providing a useful flood fingerprint for this large fluvial system before its entry into the marine environment.Conclusions
Our approach produced key data on the level and fate of suspended solids and radionuclide concentrations during flood events occurring in a large river system that could be contaminated by chronic or accidental radioactive releases. These results are of fundamental importance for further interpretations of sediment dynamics at the river mouth. 相似文献137.
Sara Nannarone Marta Cercone Rodolfo Gialletti Marco Pepe 《Journal of Equine Veterinary Science》2014
A 20-year-old gelding Lipizzaner horse was referred for onset of profuse sweating and increased heat on the right side of the head, neck, and thoracic limb. On physical examination, the horse presented tachycardia, muffled heart sounds with a pansystolic murmur, and signs of heart failure such as ventral edema, jugular distention, and pulsation. Ultrasonography examination revealed a bilateral pleural effusion and a large intrathoracic mass extending into the anterior mediastinum, which shifted the heart dorsocaudally. Thoracocentesis revealed serosanguineous fluid indicative of a melanocytic tumor. Thoracoscopy revealed a large dark mass extending into and filling the cranioventral mediastinum. The mass appearance was consistent with a melanoma, and because prognosis was poor, the owner elected euthanasia. A necropsy supported the presence of disseminated melanomas with a greater thoracic mass involving the right cervicothoracic ganglion, leading to clinical signs of sympathetic denervation. 相似文献
138.
Sergio F. Martínez-Diaz Rodolfo Martínez-Pecero Martin O. Rosales-Velázquez Reyna Alvarado-Castillo Horacio Perez-Espana John W. Tucker Jr. 《Journal of the World Aquaculture Society》2001,32(1):122-129
Abstract.— Spawning behavior and development of spotted sand bass Paralabrax maculatofasciatus were studied in the laboratory. Captive fish (15–20 cm standard length) spawned in 100-L aquaria at 24 C and 35 ppt salinity with a controlled photoperiod (13 h light: 11 h dark). Distinct courtship coloration and displays were observed. Courtship began near noon and continued all afternoon. Spawning occurred toward the surface during late afternoon. Development from fertilization to 3 d after hatching is described. Hatching occurred in 24–25 h at 24 C. Larvae were reared in 100-L aquaria with microalgae, rotifers, and Artemia . First feeding occurred 3 d after hatching, and 5.3% survival was obtained at 17 d (4.1-mm mean notochord length, 1.7–5.5 mm range). On a diet of minced clams and fish, first maturity was reached at 7.5 mo (19.5 g mean weight, 8.3–37.9 g range and 90 mm mean standard length, 66–116 mm range). 相似文献
139.
Verdida RA Hara OA Xuan X Fukumoto S Igarashi I Zhang S Dong J Inokuma H Kabeya H Sato Y Moritomo T Maruyama S Claveria F Nagasawa H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(12):1517-1521
The surface antigen P50 of Babesia gibsoni is an important candidate for the development of a diagnostic reagent for canine piroplasmosis. In order to establish an effective diagnostic method for practical use, the gene encoding truncated P50 (P50t) lacking a signal peptide and C-terminal hydrophobic regions were cloned and expressed in Escherichia coli as a fusion protein with glutathione S-transferase (GST). More than 90% portion of the GST-P50t was expressed as a soluble form, in contrast with GST-P50f (full-length), which was completely expressed as an insoluble form. This result indicates that removal of the hydrophobic signal peptide and C-terminus had dramatically improved its hydrophilicity. The purified GST-P50t was tested in an enzyme-linked immunosorbent assay (ELISA) for detection of antibodies to B. gibsoni in dogs. The ELISA with GST-P50t clearly differentiated between B. gibsoni-infected dog sera and uninfected dog sera. In addition, the ELISA detected no cross-reactivity with sera from dogs experimentally infected with the closely related parasites, B. canis canis, B. canis vogeli, and B. canis rossi. Field serum samples collected from dogs in Japan and China were examined for the diagnosis of B. gibsoni infection by using the ELISA. 14.5% (9/62), 5.8% (7/120), and 5.4% (2/37) of tested samples were positive for dogs from Okinawa, Yamaguchi, and Osaka prefectures, Japan, respectively. On the other hand, 4.8% (2/41) of tested samples were positive for dogs from Nanjing, China. These results suggest that the GST-P50t could be a reliable reagent for practical use in ELISA for the serodiagnosis of canine piroplasmosis caused by B. gibsoni. 相似文献
140.
Kannamkumarath SS Wuilloud RG Caruso JA 《Journal of agricultural and food chemistry》2004,52(19):5773-5780
On-line hyphenation of size exclusion chromatography (SEC), UV, and inductively coupled plasma mass spectrometry (ICP-MS) was used to study the molecular weight distribution patterns of several elements in Brazil nuts (Bertholletia excelsa). This technique was used for the elemental speciation of different elements of nutritional and toxicological interests such as Mg, Fe, Co, Mo, Ag, Hg, and Pb. Elemental fractionation in Brazil nuts was studied using a Superdex peptide column with resolving capacity in the range of 14 to 0.18 kDa. Three different mobile phases, Tris buffer solution (pH 8.0), phosphate buffer (pH 7.5), and CAPS buffer solution (pH 10.0), were tried for the SEC fractionation. Size exclusion fractionation of all the extracted solutions was performed using a 50 mmol L(-)(1) Tris buffer (pH 8) as the mobile phase at a flow rate of 0.6 mL min(-)(1). Three different extractions, 0.05 mol L(-)(1) NaOH, 0.05 mol L(-)(1) HCl, and hot water at 60 degrees C, were performed, and the association of elements with various molecular weight fractions was evaluated. Total elemental concentrations in the extracted samples were determined and compared with the values obtained after total digestion to calculate the recovery values. Generally, high extraction efficiency was obtained with the NaOH solution as compared with HCl and hot water except in the case of magnesium, for which HCl was found to be a good extractant. Chromatographic elution profiles for these extractions were quite distinct from each other in most cases. Most of the elemental species were found to be associated with high molecular weight fractions. To study the differences obtained during the sample-processing step, the results obtained for nuts with shell were treated differently from those obtained for nuts purchased without shell and were compared. 相似文献