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51.
Christopher J Bonar Ernesto O Boede Manuel García Hartmann Joanne Lowenstein-Whaley Esmeralda Mujica-Jorquera Scott V Parish James V Parish Michael M Garner Cynthia K Stadler 《Journal of zoo and wildlife medicine》2007,38(2):177-191
River dolphins are especially susceptible to negative human impacts. For their conservation, attempts of relocation or procreation ex situ may become important in the future to avoid their extinction. Additional knowledge and medical experiences of river dolphin management in captivity may aid such conservation efforts. The medical records and necropsy and histopathology reports on 123 captive Amazon River dolphins (Inia geoffrensis) were re-viewed. Of these 123 animals, 105 were necropsied and 70 necropsies were supported with histopathology. Eighteen animals were not necropsied. Among wild-born animals, mortality was highest in the first 2 mo immediately postcapture and transport, accounting for 32 of 123 deaths. Pneumonia and skin lesions (cutaneous and subcutaneous ulcerations and abscesses) were the most common findings, found in 44 of 105 (42%) and 38 of 105 (36%) of gross diagnoses, respectively. At least 10 of 44 cases of pneumonia diagnosed grossly included a verminous component. Cachexia, from a variety of causes, was a major gross finding in 21 animals. Fifteen animals had histologic evidence of significant renal pathology, and this was the primary cause of death in 13 cases. Hepatic pathology was found in 18 cases, and bacterial sepsis was confirmed via histology in 16 cases. Based on these findings, it may be concluded that keys to successful maintenance of this species include 1) prophylactic anthelminthic and antibiotic therapy immediately post-capture; 2) maintenance of animals in larger enclosures than in past attempts, in compatible groups, and in facilities capable of separating aggressive animals; 3) maintenance in microbiologically hygienic water quality at all times; and 4) a proactive program of preventive medicine during the immediate postcapture, quarantine, and maintenance period of captivity. 相似文献
52.
Francisco J. Escobedo David J. Nowak John E. Wagner Carmen Luz De la Maza Manuel Rodríguez Daniel E. Crane Jaime Hernndez 《Urban Forestry & Urban Greening》2006,4(3-4):105-114
Santiago, Chile's semi-arid climate and urbanized environment poses a severe limitation for the establishment and maintenance of urban forests. Municipalities, or comunas, are the main stakeholders in the management of Santiago's public urban forests. A tenable hypothesis would be that as the socioeconomic level of a comuna increases, the better the condition of a comuna's urban forest. Unfortunately, there is little comprehensive information on management, public expenditure, and structure of Santiago's public and private urban forests. To examine this hypothesis, Santiago was divided into socioeconomic strata, then using air photo interpretation and stratified field sampling, urban forest structures were quantified by socioeconomic strata. In addition, interview surveys were used to determine municipal urban forest management and expenditures for different public urban forests based on socioeconomic strata. Urban forests in the high socioeconomic strata had fewer public trees, greater tree cover, tree and leaf area density, and leaf area index than lower socioeconomic strata. The percentage of total municipal budget allocated to public urban forest management was consistent among strata, but the total public urban forest budgets were greater in the high socioeconomic strata. Public urban forest structure is related to the socioeconomic strata of Santiago's different comunas. 相似文献
53.
Irene Romero Carlos Fernandez Caballero María T. Sanchez-Ballesta María I. Escribano Carmen Merodio 《Postharvest Biology and Technology》2009,54(2):118-121
We have analyzed the influence of the stage of ripeness on L-phenylalanine ammonia-lyase (PAL) gene expression, accumulation of anthocyanins and total phenolics, and on antioxidant activity in the skin of table grapes treated with 20% CO2 + 20% O2 + 60 % N2 for 3 or 6 d at low temperature (0 °C). The residual effect of high CO2 treatment after transfer to air was also studied. In early harvested grapes, neither the anthocyanin content nor the accumulation of VcPAL mRNA was affected by any of the CO2 treatments applied. However, in late harvested grapes, the duration of high CO2 treatment determined its effect and a 6 d treatment with CO2 sustained higher levels of total phenolics and anthocyanin accumulation, and VcPAL expression than observed in untreated late harvested grapes. The increased antioxidant capacity was correlated with the total amount of phenolics and anthocyanins. Conversely, in grapes treated for 3 d with CO2 the phenylpropanoid pathway did not appear to be induced and a relationship between antioxidant activity and anthocyanins was not observed. Thus, further studies are needed to identify the most important antioxidants in these treated fruit. 相似文献
54.
Catia Pereira Itziar Aurora Montalbán Olatz García-Mendiguren Tomás Goicoa Maria Dolores Ugarte Sandra Correia Jorge Manuel Canhoto Paloma Moncaleán 《Journal of Forest Research》2016,21(3):143-150
Pinus halepensis has been described as a drought-tolerant species with high plasticity to growth in different environments. Its eco-physiological characteristics could facilitate the use of this species in large afforestations in the future scenery of climate change. Somatic embryogenesis is a biotechnological tool with potential for large-scale clonal propagation. In order to establish an improved regeneration protocol for Pinus halepensis, the effects of different temperatures (18, 23, and 28 °C) and water availability conditions (2, 3, and 4 g L?1 Gelrite®), during initiation of embryonal masses on the rate of initiation, proliferation, maturation, and the number of embryos developed, were evaluated. It was found that environmental conditions during the initiation stage of Pinus halepensis somatic embryogenesis influence the success of initiation and proliferation. In contrast, there was no effect of these conditions on the maturation rates and the number of somatic embryos. Somatic embryos were obtained in all treatments tested, indicating that plants can be produced from extreme conditions of induction, such as high temperatures (28 °C) and low water availability conditions (4 g L?1). 相似文献
55.
We generated source-sink imbalances by defoliation and sucrose supplementation by stem injection, to investigate effects of carbohydrate availability on fruitlet growth and abscission in cv. Okitsu of Satsuma mandarins (Citrus unshiu (Mak.) Marc.). Partial defoliation promoted fruitlet abscission, whereas sucrose supplementation increased citrus fruit set by more than 10%. Moreover, when applied together, sucrose supplementation counteracted the effect of partial defoliation on fruit set. When sucrose was supplied continuously from flowering until harvest, it increased the concentrations of soluble and insoluble sugars in fruits. We conclude that fruit set in citrus is highly dependent on carbohydrate availability. 相似文献
56.
Manuel Benlloch-Gonzalez Eymeric Gomes Bernard Bouvy Cyrill Poncet 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(7):715-722
This prospective clinical study evaluated the use, complications, and clinical and ultrasonographic follow-ups of end-to-end intestinal anastomoses with skin staples in naturally occurring diseases in canine small and large intestines. Intestinal anastomoses were performed in 14 dogs and pre-, peri-, and postoperative data were recorded. Postoperative clinical and ultrasound evaluations were performed at regular intervals for 1 year. The mean time taken to construct the anastomosis was 5 min. There were no intraoperative complications. Hemorrhage and colonic stricture were the main postoperative complications. Staple loss occurred in 2 cases. Absence of wall layering and focal wall thickening were observed in all cases at each ultrasonographic follow-up. Hyperechoic fat was observed in all but 1 of the cases at month 1. Nine dogs were alive with normal digestive function at the end of the study. The skin stapler technique enabled rapid construction of consistent anastomoses with inexpensive stapling material. 相似文献
57.
Contribution of family labour to the profitability and competitiveness of small-scale dairy production systems in central Mexico 总被引:1,自引:1,他引:0
Rodolfo Rogelio Posadas-Domínguez Carlos Manuel Arriaga-Jordán Francisco Ernesto Martínez-Castañeda 《Tropical animal health and production》2014,46(1):235-240
The objective of this work was to determine the effect of family labour on the profitability and competitiveness of small-scale dairy farms in the highlands of Central Mexico. Economic data from 37 farms were analysed from a stratified statistical sampling with a Neyman assignment. Three strata were defined taking herd size as criterion. Stratum 1: herds from 3 to 9 cows plus replacements, Stratum 2: herds from 10 to 19 cows and Stratum 3: herds from 20 to 30 cows. The policy analysis matrix was used as the method to determine profitability and competitiveness. The coefficient of private profitability (CPP) when the economic cost of family labour is included in the cost structure was 8.0 %, 31.0 % and 46.0 %. When the economic cost of family labour is not included, CPP increase to 47.0 %, 57.0 % and 66.0 % for each strata, respectively. The private cost ratio (PCR) when family labour is included was 0.79, 0.51 and 0.42 for strata 1, 2 and 3, respectively. When family labour is not included, the PCR was 0.07, 0.25 and 0.26. Net profit per litre of milk including family labour was US$0.03 l-1 for Stratum 1, US$0.09 for Stratum 2 and US$0.12 l-1 for Stratum 3; but increased to $0.12, 0.14 and 0.15, respectively, when the economic cost of family labour is not included. It is concluded that family labour is a crucial factor in the profitability and competitiveness of small-scale dairy production. 相似文献
58.
Manuel F. Chamorro Paul H. Walz Deborah M. Haines Thomas Passler Thomas Earleywine Roberto A. Palomares Kay P. Riddell Patricia Galik Yijing Zhang M. Daniel Givens 《Canadian journal of veterinary research》2014,78(2):81-88
Colostrum-replacement products are an alternative to provide passive immunity to neonatal calves; however, their ability to provide adequate levels of antibodies recognizing respiratory viruses has not been described. The objective of this study was to compare the serum levels of IgG at 2 d of age and the duration of detection of antibodies to bovine viral diarrhea virus 1 (BVDV-1), bovine viral diarrhea virus 2 (BVDV-2), bovine respiratory syncytial virus (BRSV), bovine herpesvirus 1 (BHV-1), and bovine parainfluenza virus 3 (BPIV-3) in calves fed maternal colostrum (MC) or a colostrum replacement (CR) at birth. Forty newborn male Holstein calves were assigned to the CR or the MC group. Group CR (n = 20) received 2 packets of colostrum replacement (100 g of IgG per 470-g packet), while group MC (n = 20) received 3.8 L of maternal colostrum. Blood samples for detection of IgG and virus antibodies were collected from each calf at birth, at 2 and 7 d, and monthly until the calves became seronegative. Calves in the MC group had greater IgG concentrations at 2 d of age. The apparent efficiency of absorption of IgG was greater in the MC group than in the CR group, although the difference was not significant. Calves in the CR group had greater concentrations of BVDV neutralizing antibodies during the first 4 mo of life. The levels of antibodies to BRSV, BHV-1, and BPIV-3 were similar in the 2 groups. The mean time to seronegativity was similar for each virus in the 2 groups; however, greater variation was observed in the antibody levels and in the duration of detection of immunity in the MC group than in the CR group. Thus, the CR product provided calves with more uniform levels and duration of antibodies to common bovine respiratory viruses. 相似文献
59.
Manuel Martin‐Flores Daniel M Sakai Luis Campoy RD Gleed 《Veterinary anaesthesia and analgesia》2014,41(3):269-277
ObjectiveTo evaluate if return of spontaneous ventilation to pre-relaxation values indicates complete recovery from neuromuscular blockade.Study designProspective, with each individual acting as its own control.AnimalsTen healthy adult female Beagle dogs weighing 6.2–9.4 kg.MethodsDogs were anesthetized with propofol, dexemedetomidine and isoflurane. Spontaneous ventilation was assessed by measuring end-tidal CO2, expired tidal volume, peak inspiratory flow, respiratory rate and minute ventilation. Vecuronium 25 μg kg?1 IV was administered and neuromuscular block was evaluated by measuring the train-of-four (TOF) ratio with acceleromyography in the hind limb. During spontaneous recovery from neuromuscular block, the TOF ratio when each ventilatory variable returned to baseline was recorded.ResultsThis dose of vecuronium produced moderate neuromuscular block in all dogs, with TOF ratio values of 0–18% at maximal block. Expired tidal volume, peak inspiratory flow and minute ventilation returned to pre-relaxation values when the median TOF ratio was ≤ 20%. The median TOF ratio was 42% when the end-tidal CO2 returned to pre-relaxation values.Conclusions and clinical relevanceSignificant residual neuromuscular block could be measured at the hind limb with acceleromyography when ventilation had spontaneously returned to pre-vecuronium values. Monitoring spontaneous ventilation, including end-tidal CO2, expired tidal volume, peak inspiratory flow or minute ventilation cannot be used as a surrogate for objective neuromuscular monitoring, and this practice may increase the risk of postoperative residual paralysis. 相似文献
60.
The effect of scheduled use of high‐protein and low‐protein diets on body weight and fry production of Nile tilapia, Oreochromis niloticus (L.), was determined. A preliminary feeding trial was first conducted on fingerlings. These were fed a high‐protein diet (H, 25% protein) or a low‐protein diet (L, 18% protein) daily, or diet H for 1–3 days followed by diet L for 1–4 days. Final body weight was significantly higher (P < 0.05) in fish fed diet H daily and in fish fed diet H for 2–3 days followed by diet L for 1 day (2H?1L and 3H?1L). Fingerlings on 1H?1L and 3H?2L had slightly lower growth. Based on the response of the fingerlings, five feeding schedules were tested with the broodstock. A high‐protein diet (HP, 40%) and a low‐protein diet (LP, 25%; same as H for fingerlings) were used. Feeding schedules significantly influenced body weight of female but not the male fish. Fry production was not significantly affected by the feeding schedule for broodstock. When growth, fry production and saving in feed cost were all considered, the broodstock on 1HP?1LP and 3HP?2LP feeding schedules both gave the highest overall performance. These findings give fish farmers an option in the management of feeding of tilapia broodstock. 相似文献