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61.
The present work evaluated the use of molasses as a carbon source during the nursery rearing of Farfantepenaeus brasiliensis in a Biofloc technology system. During a 30 days trial, three replicate tanks were randomly assigned to the following treatments: 1.) molasses (with molasses addition) and 2.) control (without molasses addition). Bacteriological analysis was used to quantify the abundance of presumptive Vibrio spp. between control and molasses treatment. The concentration of this microorganism was lower in molasses compared with control. For the immunological analysis, shrimp haemolymph was collected to determine the total haemocyte count and the total protein concentration. The immunological results were not different between treatments. The performance results of shrimp reared with molasses addition showed that the survival rate (88.87 ± 6.36), the mean final weight (1.22 ± 0.38) and the specific growth rate (0.0309 ± 1.06) were significantly higher compared with control (80.5 ± 2.42; 1.03 ± 0.13; 0.0256 ± 0.97 respectively). Moreover, the addition of molasses contributed to the maintenance of water quality and lower concentration of presumptive Vibrio spp. The control presented an unstable variation of Vibrio spp. reaching values of 80 × 102 CFU/ml, while the highest result of molasses was 20 × 102 CFU/ml, confirming the beneficial effects of molasses addition.  相似文献   
62.
The objective of this study was to test the hypothesis that growth performance and carcass characteristics of pigs fed diets containing cold-fermented, low oil distillers dried grains with solubles (DDGS) is not different from that of pigs fed diets containing conventional DDGS regardless of the physical form of the diets. A total of 160 barrows and gilts were used. There were 4 diets, 10 pens per diet, and 4 pigs per pen. Pigs were weaned at 21 d of age and fed a common phase 1 diet that did not contain DDGS during the initial 7 d post-weaning. Pigs were then allotted to the four diets that were arranged in a 2 × 2 factorial design with two sources of DDGS (cold-fermented and conventional DDGS) and two diet forms (meal and pellets). Pigs were fed phase 2 diets from day 7 to 21 and phase 3 diets from day 21 to 43 post-weaning. All diets were based on corn and soybean meal, but phase 2 diets also contained 15% DDGS and phase 3 diets contained 30% DDGS. From day 43, pigs were fed grower diets for 38 d, early finisher diets for 38 d, and late finisher diets for 18 d and these diets also contained 30% DDGS. Feed was provided on an ad libitum basis and daily feed allotments were recorded. Pigs were weighed at the beginning of each phase and at the conclusion of the experiment. On the last day of the experiment, the pig in each pen with a body weight that was closest to the pen average was slaughtered and carcass measurements were determined. Combined results for the two nursery phases indicated that feeding meal diets instead of pelleted diets increased (P < 0.001) average daily feed intake and decreased (P < 0.05) gain to feed ratio (G:F). However, no differences between the two sources of DDGS were observed for the overall growth performance of weanling pigs. For the entire growing-finishing period, the source of DDGS did not affect growth performance, but pigs fed meal diets had reduced (P < 0.001) G:F compared with pigs fed the pelleted diets. There were no differences between the two sources of DDGS for carcass characteristics. Back fat was greater (P < 0.05) for pigs fed pelleted diets than for pigs fed meal diets. In conclusion, no differences in growth performance or carcass characteristics between pigs fed cold-fermented DDGS and pigs fed conventional DDGS were observed. However, pigs fed pelleted diets had greater G:F and greater back fat than pigs fed meal diets.  相似文献   
63.
64.
Soil acidity is one of the most important factors limiting crop production. The objective of this work was to evaluate the effects of limestone application on the soil chemical properties, nutrition and yield of mango plants in an orchard under implementation. The design was randomized blocks, with five limestone doses (0; 2; 4; 6 and 8 t ha?1) and four replications. Soil chemical analyses were performed (at 12, 24, 36 and 48 months after the experiment implementation) in the layers 0–20; 20–40 and 40–60 cm deep. Nutrition status and yield were assessed during the first and second crop seasons. The highest fruit yield was associated with the application of 3.9 and 3.8 t ha?1 of limestone in the 2008/09 and 2009/10 seasons, respectively, that is, the dose recommended by the literature for raising base saturation to 80%, as a function of the fertility conditions of the soil initially obtained.  相似文献   
65.

Objective

To evaluate the effect of hyaluronidase on uptake, duration and speed of elimination of xylazine–tiletamine–zolazepam administered in the subcutaneous fat over the dorsal lumbar region of swine.

Study design

Blinded, randomized, crossover study.

Animals

Six healthy Landrace/Large White pigs weighing 132 ± 24 kg (mean ± standard deviation).

Methods

Animals were administered xylazine (1 mg kg?1) and tiletamine–zolazepam (8 mg kg?1) (control treatment, CON), or xylazine–tiletamine–zolazepam at the same doses with hyaluronidase (400 IU) (treatment HYA). The treatments were administered into the dorsal lumbar adipose tissue, 2.5–3.0 cm laterally from the spinous process of the second lumbar vertebra. The latency, anesthesia and recovery periods were measured. Heart rate, noninvasive systolic, diastolic, and mean arterial pressures, respiratory rate, hemoglobin oxygen saturation and rectal temperature were recorded every 10 minutes for up to 50 minutes.

Results

One animal in CON and one animal in HYA were responsive to stimulation and did not allow safe handling. No significant difference was found between treatments for latency (CON 11.3 ± 5.9 minutes, HYA 7.4 ± 5.1 minutes) and anesthesia (CON 53 ± 53 minutes, HYA 49 ± 38 minutes) periods. Recovery period was shorter in HYA (9 ± 6 minutes) than in CON (32 ± 16 minutes) (p < 0.05). Physiological variables were not significantly changed over time and were within accepted normal clinical limits for the species in both treatments.

Conclusion and clinical relevance

Hyaluronidase (400 IU) administered into adipose tissue in pigs did not reduce the latency and duration of dissociative anesthesia, but was associated with faster recovery.  相似文献   
66.
The aim of the current study is to diagnose Brucella spp. infection using methods such as serology, bacterial isolation, and molecular analysis in buffaloes bred in Maranhão State. In order to do so, 390 samples of buffalo serum were subjected to serological tests, to Rose Bengal Plate Test (RBPT) and to 2-mercaptoethanol (2-ME) combined with slow agglutination test (SAT). Vaginal swabs were collected from seropositive animals and subjected to bacterial isolation and to generic PCR. According to the serological test, 16 animals had a positive reaction to the confirmatory test (2-ME/SAT). As for bacterial isolation, three samples resulted in the isolation of Brucella spp.-characteristic colonies, which were confirmed through PCR. These results confirmed Brucella spp. infection in the buffalo herd from Maranhão State.  相似文献   
67.

Background  

Recent evidence suggests a two-way interaction between the immune and circadian systems. Circadian control of immune factors, as well as the effect of immunological variables on circadian rhythms, might be key elements in both physiological and pathological responses to the environment. Among these relevant factors, galectin-1 is a member of a family of evolutionarily-conserved glycan-binding proteins with both extracellular and intracellular effects, playing important roles in immune cell processes and inflammatory responses. Many of these actions have been studied through the use of mice with a null mutation in the galectin-1 (Lgals1) gene. To further analyze the role of endogenous galectin-1 in vivo, we aimed to characterize the circadian behavior of galectin-1 null (Lgals1 -/-) mice.  相似文献   
68.
Objective – To evaluate the tolerance of a continuous positive airway pressure (CPAP) mask in tranquilized dogs and compare PaO2 in arterial blood in dogs receiving oxygen with a regular face mask or CPAP mask set to maintain a pressure of 2.5 or 5 cm H2O. Design – Prospective, randomized clinical study. Setting – University teaching hospital. Animals – Sixteen client‐owned dogs without evidence of cardiopulmonary disease were studied. Interventions – Eight animals were randomly assigned to each of 2 treatment groups: group A received 2.5 cm H2O CPAP and group B received 5 cm H2O CPAP after first receiving oxygen (5 L/min) by a regular face mask. Animals were tranquilized with acepromazine 0.05 mg/kg, IV and morphine 0.2 mg/kg, IM. An arterial catheter was then placed to facilitate blood sampling for pHa, PaO2, and PaCO2 determinations before and after treatments. Direct mean arterial pressure, heart rate, respiratory rate, and temperature were also recorded after each treatment. Measurements and Main Results – CPAP administration was well tolerated by all animals. The mean arterial pressure, heart rate, respiratory rate, temperature, PaCO2, and pHa, did not differ at any time point between groups. Differences were seen in oxygenation; in group A, PaO2 significantly increased from a mean of 288.3±47.5 mm Hg with a standard mask to a mean of 390.3±65.5 mm Hg with the CPAP mask and in group B, PaO2 increased similarly from 325.0±70.5 to 425.2±63.4 mm Hg (P<0.05); no differences were detected between the 2 CPAP treatments. Conclusions – In healthy tranquilized dogs noninvasive CPAP is well tolerated and increases PaO2 above values obtained when using a regular face mask.  相似文献   
69.
An agent-based approach to model land-use change at a regional scale   总被引:5,自引:1,他引:4  
Land-use/cover change (LUCC) is a complex process that includes actors and factors at different social and spatial levels. A common approach to analyse and simulate LUCC as the result of individual decisions is agent-based modelling (ABM). However, ABM is often applied to simulate processes at local scales, while its application in regional studies is limited. This paper describes first a conceptual framework for ABM to analyse and explore regional LUCC processes. Second, the conceptual framework is represented by combining different concepts including agent typologies, farm trajectories and probabilistic decision-making processes. Finally, the framework is illustrated through a case study in the Netherlands, where processes of farm cessation, farm expansion and farm diversification are shaping the structure of the landscape. The framework is a generic, straightforward approach to analyse and explore regional LUCC with an explicit link to empirical approaches for parameterization of ABM.  相似文献   
70.
Bacterial communities in sediments underneath milkfish cages and adjacent off‐cage areas in Bolinao, Lingayen Gulf, West Philippine Sea were characterized using PCR‐denaturing gradient gel electrophoresis to assess influence of the fish farming to the sediments. The sediments in the fish cage (FC) area showed anoxic conditions [redox potential of ?165 to ?213 mV and acid‐volatile sulphide‐sulphur (AVS‐S) of 0.55–1.88 mg g?1 (dry weight)] compared to the relatively oxic off‐cage area [redox potential of 72–81 mV and AVS‐S of 0.09–0.14 mg g?1 (dry weight)]. The composition of the microbial populations revealed influence of the fish feed sedimentation with higher dominance of putative sulphate‐reducing bacteria (SRB) in the FC area. Compositions of the bacterial taxa showed dominance of the Bacteroidetes group and Deltaproteobacteria. The results suggest that the fish feeds created a new suitable environment, in which reductive microorganisms such as SRB, ferric‐ion‐reducing bacteria and nitrate‐reducing bacteria can thrive. Organic load from the feed and quantity of its leftover constituents may be the key factors that influence the structure of the bacterial community in the sediments of the milkfish farms.  相似文献   
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