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621.
A 13-year-old neutered male miniature dachshund suffered ~30% total skin loss following an attack by another dog. After numerous failed attempts at wound management and closure, the wound was successfully healed by epithelialization using tilapia skin grafts. At each tilapia skin graft placement, the wound bed appeared pink, clean, and healthy with excellent progression of epithelialization at all edges. With use of the tilapia grafts, epithelialization occurred at a rate of 1.76 mm/day. As a result, the wound reached complete closure by epithelialization with no evidence of wound contracture in 102 days.Key clinical message:Tilapia skin grafts were successfully used for management of a large bite wound in a dog and may promote accelerated epithelialization in full thickness skin wounds.  相似文献   
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624.
We recently showed that dietary supplementation with key functional amino acids (FAA) improves growth performance and immune status of Salmonella Typhimurium (ST)-challenged pigs. It is not known if ST-challenged pigs will benefit from a longer adaptation period to FAA. The objective of this study was to evaluate the effects of different adaptation periods to diets containing FAA above requirements for growth on performance and immune response of weaned pigs subsequently challenged with ST. A total of 32 mixed-sex weanling pigs (11.6 ± 0.3 kg) were randomly assigned to 1 of 4 dietary treatments, being a basal amino acid (AA) profile fed throughout the experimental period (FAA−) or a functional AA profile (FAA+; Thr, Met, and Trp at 120% of requirements) fed only in the postinoculation (FAA+0), for 1 wk pre- and postinoculation (FAA+1), or throughout the experimental period (FAA+2). After a 14-d adaptation period, pigs were inoculated with ST (2.15 × 109 CFU/mL). Growth performance, body temperature, fecal score, acute-phase proteins, oxidant/antioxidant balance, score for ST shedding in feces and intestinal colonization, and fecal and digesta myeloperoxidase (MPO) were measured pre- and postinoculation. Postinoculation body temperature and fecal score, serum haptoglobin, plasma superoxide dismutase (SOD), malondialdehyde (MDA), and fecal MPO were increased while serum albumin and plasma reduced glutathione (GSH):oxidized glutathione (GSSG) were reduced compared to pre-inoculation (P < 0.05). Average daily gain and G:F were greater in FAA+2 pigs compared to FAA− pigs (P < 0.05). Serum albumin was higher in FAA+2 and FAA+1 compared to FAA+0 and FAA− pigs (P < 0.05) while FAA+2 pigs had lower haptoglobin compared to FAA− (P < 0.05). Plasma SOD was increased and GSH:GSSG was decreased in FAA− pigs compared to the other treatments (P < 0.05). Score for ST shedding in feces was progressively lower from d 1 to 6 regardless of treatment (P < 0.05) and was lower in FAA+2 pigs compared to FAA− and FAA+0 (P < 0.05). Counts of ST in colon digesta were higher in FAA− and FAA+0 pigs compared to FAA+2 (P < 0.05). Fecal and colonic digesta MPO were lower in FAA+2 and FAA+1 pigs compared to FAA− (P < 0.05). These results demonstrate a positive effect of a longer adaptation period to FAA-supplemented diets on performance and immune status of weaned pigs challenged with Salmonella.  相似文献   
625.
Goal, Scope and Background  Temperature and soil moisture content are important environmental variables in bioremediation technologies. Optimizing these variables in-situ would enhance and maintain remediation of hazardous wastes during cold winter seasons or in cold regions and may lead to reduced maintenance and/or cost. The effect of elevated temperature and soil moisture on bioremediation efficiency was investigated using a laboratory mesocosm approach. Selected polycyclic aromatic hydrocarbons (PAHs) and phenols degradation in contaminated flooded soils, commonly found in Superfund sites situated in coastal plains sediments/soils, were evaluated in the mesocosms. Material and Methods  Four laboratory mesocosm treatments in triplicate simulating in-situ bioremediation of contaminated site soils using an immobilized microbe bioreactor system, i.e., bioplug, were established to evaluate temperature effects. Elevated temperature treatments of site soils with and without contaminant-specific microorganisms were established at a temperature of 42±2°C. Similarly, treatment of site soils with and without contaminant-specific microorganisms were established at an ambient temperature of 21±1°C. Composite samples were analyzed for selected PAHs and chlorinated phenols to determine rates of mineralization and overall remediation efficiency for different temperature regimes. Results  Mesocosm studies indicated that the high temperature inoculated treatment demonstrated a significant reduction in mean total PAHs and total phenols with a kinetic rate (KR) of 76±13 ng g−1 d−1 in 49 days (approximately 84% reduction; p<0.01) The KR for low temperature inoculated treatment was 54±1 ng g−1 d−1 in 49 days (approximately 66% reduction; p<0.01). High temperature non-inoculated mesocosms exhibited significant mineralization of all constituents with KR of 15±6 ng g−1 d−1 (approximately 65% reduction; p<0.01) in 49d compared to 54% reduction for low temperature non-inoculated treatment with KR of 12±3 ng g−1 d−1 (p=0.1794). Phenol compounds in inoculated treatments were also significantly reduced (65%, p<0.01) at elevated temperatures compared to ambient (52%, p<0.01). Discussion  Increased bioavailability and desorption were noted for elevated temperature and moisture in the soil laboratory mesocosms simulating a field in situ remediation protocol. This protocol employing the application of immobilized microflora indicated that in situ systems provide an economical advantage if optimal elevated temperature and moisture are controlled properly. Results also suggested that temperature and moisture optimization needs to be combined with efficient nutrients delivery systems for impacted soils/sediments. Conclusions  The study demonstrated that temperature and soil moisture contents are important factors in the success of in-situ bioremediation techniques at hazardous waste sites situated in a coastal zone. Kinetic rates were significantly enhanced to remediate known recalcitrant compounds (PAHs and phenols) in aged soil. Recommendations and Perspectives  The placement of a preferred microbial consortia such as an immobilized microbial population in an entrained bioreactor, i.e., bioplug, can significantly reduce constituents of concern in a timely manner for contaminated soils/sediments. However, frequent monitoring of the soil temperature, moisture content, nutrient level, and dissolved oxygen is necessary to achieve predictable kinetic rates of mineralization. ESS-Submission Editor: Dr. Teresa Cutright (tcutright@uakron.edu)  相似文献   
626.
To select and characterize potential probiotic bacteria from the gut microbiota of Siberian sturgeon (Acipenser baerii), 129 strains isolated from the hindgut were screened for antagonistic activity against five fish pathogens. Ten isolates showed antagonism towards three or more pathogens. Nine of these isolates were Gram‐positive, belonging to Lactococcus (seven) and Bacillus (two), and a single strain belonging to the Gram‐negative Citrobacter. These inhibitory isolates were identified using genetic, phentotypic and biochemical traits, and further characterized by in vitro tests assessing the adhesion and growth in mucus and resistance to gastric and intestinal fluids. The candidate probiotics were determined to be non‐pathogenic through an in vivo study. Based on these assays, Lactococcus lactis ssp. lactis STG45 and STG81 showed the broadest inhibitory potential, a high viability in simulated gastrointestinal juice and the highest adhesion capacity to mucus. They were therefore selected as the most promising candidate probiotics. This is the first study screening probiotics among the gut microflora of Siberian sturgeon.  相似文献   
627.
Cervical vertebral malformation is one of the most common causes of ataxia in horses. The most important factor in the diagnosis of cervical vertebral malformation is the identification of cervical vertebral canal stenosis, but published data for minimum sagittal diameter ratios in adult horses are only available for C4-C7 intravertebral sites. Intra- and intervertebral sagittal diameter ratios at C2-C7 were evaluated in 26 ataxic horses, for which a complete clinical and neuropathological evaluation was undertaken. Eight of these horses were diagnosed with cervical vertebral malformation. In these horses the majority of compressive lesions were intervertebral. The mean sagittal diameter ratios of horses with cervical vertebral malformation were significantly smaller than those of horses without cervical vertebral malformation, and for an individual horse in our study, the site with the smallest intervertebral sagittal diameter ratio was always the site at which the spinal cord was compressed. Mean sagittal diameter ratio intravertebral site measurements of horses with cervical vertebral malformation were smaller than those of horses without cervical vertebral malformation; however, the site of compression could not be predicted from the data. For our dataset, horses with a sagittal diameter ratio of < or = 0.485 at any inter- or intravertebral site could be correctly classified as having cervical vertebral malformation, and sagittal diameter ratio measurements were an effective tool to identify at least one site of compression in an individual case.  相似文献   
628.
Previously healthy sows, seropositive to Mycoplasma hyopneumoniae, developed clinical signs of mycoplasmosis, as well as increasing amounts of antibodies to M. hyopneumoniae during an outbreak of the disease in a herd. During the early phase of the outbreak, young piglets (2 weeks) with maternal antibodies remained healthy while older seronegative piglets (4–7 weeks) developed the disease. The duration of the maternal antibodies to M. hyopneumoniae varied between litters and was related to the amount of antibodies in the serum of the dam. In sows, the level of serum antibodies decreased continuously from 4 weeks ante partum to partus, and the level of antibodies in the whey of colostrum was comparable to that in serum 4 weeks ante partum. After loss of maternal antibodies to M. hyopneumoniae, seropositive animals were not found among piglets younger than 9 weeks. Therefore peripheral blood mononuclear cells (PBMC) were collected from various age categories of piglets in order to measure the ability to produce antibodies to M. hyopneumoniae in vitro. PBMC obtained from piglets aged 1 and 3 weeks produced few antibodies to M. hyopneumoniae. Significantly higher levels of antibodies to M. hyopneumoniae were produced by PBMC obtained from pigs aged 5–9 weeks. Thus, the ability of PBMC to produce antibodies to M. hyopneumoniae in vitro seemed to be age-dependent.  相似文献   
629.
Studies about nitrogen (N) mineralization and nitrification in deep soil layers are rare because N processes are considered to occur mainly in topsoil that hosts active and diverse microbial communities. This study aimed to measure the soil potential net N mineralization (PNM) and nitrification (PNN) down to 4 m depth and to discuss factors controlling their variability. Twenty-one soil cores were collected at the Restinclières agroforestry experimental site, where 14-year-old hybrid walnut trees were intercropped with durum wheat. Soil cores were incubated in the dark in the laboratory at both 6 and 25°C. The soil was a deep calcic fluvisol with a fluctuating water table. It featured a black layer that was very rich in organic matter and permanently water saturated at depths between 3.0 and 4.0 m. The mean soil mineral N content was 3 mg N kg−1 soil in the upper 0.0–0.2 m layer, decreasing until a depth of 2 m and increasing to the maximum value of 25.8 mg N kg−1 soil in the black layer. While nitrate (NO3) was the dominant form of mineral N (89%) in the upper 0.0–0.2 m layer, its proportion progressively decreased with depth until ammonium (NH4+) became almost the only form of mineral N (97%) in the saturated black layer. Laboratory soil incubation revealed that PNM and PNN occurred at all depths, although the latter remained low at 6°C. The soil nitrate content in the black layer was multiplied by 48 times after 51 days of incubation at 25°C, whereas it was almost inexistent at the sampling date. While the soil total N, the pH and the incubation temperature explained 84% of the variation in PNM, only 29% of the percent nitrification variance was explained by the incubation temperature (Tinc) and the soil C-to-N ratio. These results point out the necessity to consider soil potential net N mineralization and nitrification of deep soil layers to improve model predictions.  相似文献   
630.
Three experiments were carried out to determine the crude protein requirements for maintenance (CPm) and weight gain (CPg) of meat quail and to develop protein‐requirement prediction models. Experiment 1 was conducted to determine CPm by the nitrogen‐balance technique. The regression of nitrogen balance on nitrogen intake revealed a CPm requirement of 2.94 g/kg0.75/day. Experiment 2 was aimed at determining CPm by the comparative‐slaughter technique. Retained nitrogen (RN) and nitrogen intake (NI) were quantified considering the metabolic weight of the birds. The linear regression of RN on NI provided a CPm estimate of 6.63 g/kg0.75/day. Experiment 3 was conducted to determine CPg. The regression of body nitrogen from the carcasses on fasted body weight revealed CPg estimates of 407.68 (0–7 days), 501.76 (8–14 days), 470.40 (0–14 days), 517.44 (15–21 days), 627.20 (22–28 days), 423.36 (29–35 days), and 517.44 mg/g (15–35 days). The protein‐requirement prediction models developed for meat quail aged 0–7, 8–14, 0–14, 15–21, 22–28, 29–35, and 15–35 days were CP = 2.94.W0.75 + 0.408.G; CP = 2.94.W0.75 + 0.502.G; CP = 2.94.W0.75 + 0.470.G; CP = 2.94.W0.75 + 0,517.G; CP = 2.94.W0.75 + 0.627.G; CP = 2.94.W0.75 + 0.423.G; CP = 2.94.W0.75 + 0.517.G, respectively, where: W0.75 =  metabolic weight (kg), and G =  daily weight gain (g).  相似文献   
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