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151.
Current study investigated the effect of feeding systems (conventional vs organic rearing) on carcass characteristics, meat quality and fatty acid composition of Musculus longissimus dorsi of Korean native black barrows (KNP). Thirty pigs were reared under a conventional feeding system at indoor area of 1 m2 per head, while another thirty pigs were fed an indoor area with organic saw dusts of 1 m2 and an outdoor area with free ranges of 1 m2 for each pig for organic system. Diet for the organic rearing was also provided according to the guideline for organic pork products. Warner–Bratzler shear force was lower and water holding capacity was higher for pork produced under the organic guidelines. However, pork produced by an organic system did not affect sensory traits compared to pork produced by a conventional one. In addition, longissimus muscle from organically reared pigs had significantly (P < 0.05) higher myoglobin content and consequently higher CIE a?-values compared with those for the conventionally-reared pigs (P < 0.05). The organic pork resulted in significantly (P < 0.05) higher polyunsaturated fatty acid (PUFA) and unsaturated fatty acid contents, as well as a higher n-3 PUFA than the conventional one (P < 0.05).  相似文献   
152.
The ethanolic extract of the fruit bark from Magonia glabrata yielded shikimic acid, scopoletin, sitosterol glycoside and 2-O-methyl-l-inositol. Antioxidant, icthyotoxicity and brine shrimp lethality activities were observed in this extract. The major constituent, 2-O-methyl-l-inositol, was found to be inactive in two assays but showed moderate activity as a radical scavenger.  相似文献   
153.
An 8-year-old, spayed female, domestic shorthair cat with a history of hyperthyroidism, anorexia, dehydration, cervical ventroflexion, and behavioral changes was referred to the Iowa State University College of Veterinary Medicine. The cat was obtunded, with severe dehydration (15%) and hypothermia (86 degrees F), and severe muscle atrophy and fasciculations. Serum biochemical abnormalities included severe hypernatremia (195 mmol/L, reference interval 155-165 mmol/L), hyperchloridemia (161 mmol/L, reference interval 123-131 mmol/L), and hypokalemia (3.6 mmol/L, reference interval 4.0-5.7 mmol/L). Calculated osmolality was 418 mOsm/kg (reference interval 280-305 mOsm/kg), attributable to the hypernatremia. The cat was kept warm and given fluid and glucocorticoid therapy and supportive measures but remained unresponsive. Hypernatremia and hyperosmolality improved through day 3, when the cat died suddenly. At necropsy, a 1.25-cm mass was found in the area of the thalamus and interthalamic adhesion that extended to the ventral aspect of the cerebrum. The histologic and immunohistochemical diagnosis was B-cell lymphoma. Hypernatremia and hyperosmolality in this cat were attributed to primary adipsia and hypothalamic dysfunction secondary to effacement of central nervous system tissue by neoplastic lymphocytes. To the authors' knowledge, this is the first reported case of central nervous system lymphoma, confirmed by use of immunohistochemical analysis as a B-cell phenotype, associated with hypernatremia. It also is the first reported case of lymphoma in animals limited to the thalamus, hypothalamus, and cerebrum, with no involvement of the spinal cord.  相似文献   
154.
Surface wettability and topography are recognized as critical factors influencing cell behavior on biomaterials. So far only few works have reported cell responses on surfaces exhibiting extreme wettability in combination with surface topography. The goal of this work is to study whether cell behavior on superhydrophobic surfaces is influenced by surface topography and polymer type. Biomimetic superhydrophobic rough surfaces of polystyrene and poly(L-lactic acid) with different micro/nanotopographies were obtained from smooth surfaces using a simple phase-separation based method. Total protein was quantified and showed a less adsorption of bovine serum albumin onto rough surfaces as compared to smooth surfaces of the same material. The mouse osteoblastic MC3T3-E1 cell line and primary bovine articular chondrocytes were used to study cell attachment and proliferation. Cells attached and proliferate better in the smooth surfaces. The superhydrophobic surfaces allowed cells to adhere but inhibited their proliferation. This study indicates that surface wettability, rather than polymer type or the topography of the superhydrophobic surfaces, is a critical factor in determining cell behavior.  相似文献   
155.
As mammals are unable to synthesize essential polyunsaturated fatty acids (PUFA), these compounds need to be taken in through diet. Nowadays, obtaining essential PUFA in diet is becoming increasingly difficult; therefore this work investigated the suitability of using macroalgae as novel dietary sources of PUFA. Hence, 17 macroalgal species from three different phyla (Chlorophyta, Phaeophyta and Rhodophyta) were analyzed and their fatty acid methyl esters (FAME) profile was assessed. Each phylum presented a characteristic fatty acid signature as evidenced by clustering of PUFA profiles of algae belonging to the same phylum in a Principal Components Analysis. The major PUFA detected in all phyla were C18 and C20, namely linoleic, arachidonic and eicosapentaenoic acids. The obtained data showed that rhodophytes and phaeophytes have higher concentrations of PUFA, particularly from the n-3 series, thereby being a better source of these compounds. Moreover, rhodophytes and phaeophytes presented “healthier” ∑n-6/∑n-3 and PUFA/saturated fatty acid ratios than chlorophytes. Ulva was an exception within the Chlorophyta, as it presented high concentrations of n-3 PUFA, α-linolenic acid in particular. In conclusion, macroalgae can be considered as a potential source for large-scale production of essential PUFA with wide applications in the nutraceutical and pharmacological industries.  相似文献   
156.
During the first 2 years of larval rearing trials with Atlantic bluefin tuna, survival was a challenging issue. As bacterial colonization of the gut has been shown to play a key role for other species, we studied the profiles of the microbiota associated with individual larvae at different stages in three distant hatcheries. The Bacterial Community Profile (BCP) was quantified based on PCR‐DGGE analyses of partial amplicons from 16S rDNA. Considerable individual variability in BCP was observed before onset of feeding, and the BCP did not show regular fluctuation during ontogenesis. Microalgae were added to the rearing tanks in two of the three hatcheries, but it was not possible to distinguish the effect of location from the effect of algal addition on BCP. In one hatchery, the larvae were reared either with algal addition or in mesocosm, but due to high individual variability, no significant difference in BCP was detected between the two groups. It was hypothesized that this variability was caused by differences in health, physiological status and developmental stage of the larvae. A practical conclusion from the study is the need to analyse a considerable number of individuals to reflect statistically significant differences between the microbial communities associated with rearing groups.  相似文献   
157.
Following the development of demand-feeding systems, many experiments have been conducted to explore feeding motivation and feed intake in farmed fish. This work aims to review a selection of studies in the field, focusing on three key factors, related to demand feeding and fish welfare. Firstly, we outline how demand feeders should be considered when developing feed management strategies for improving welfare in production conditions. Secondly, via laboratory demand-feeding experiments, we show self-feeding activities depend not only on feeding motivation and social organisation, but also on individual learning capacity and risk-taking behaviour. Thirdly, we report encouraging results demonstrating that when presented with two or more self-feeders containing complementary foods, fish select a diet according to their specific nutritional requirements, suggesting that demand feeders could be used to improve welfare by allowing fish to meet their nutritional needs.  相似文献   
158.
Three groups (wild—WS, semi-pond—SPS, and pond-cultured—PS) of ide Leuciscus idus (L.) were examined. Each group consisted of 30 females and 10 males, aged 5–8 years. All groups were stimulated with two agents: carp pituitary homogenate (CPH) and a synthetic hormonal preparation Ovopel. The amount of ovulating females decreased in conjunction with females’ domestication level, mainly because of very low efficacy of CPH for pond-reared ide stimulation. The percentage of ovulating females stimulated with Ovopel (97.0 %) was significantly higher comparing to CPH (63.0 %). No significant differences were found in latency time between the groups but spawning synchronization increased in conjunction with ide domestication. The positive correlation between domestication level and latency time, i.e., the higher the domestication level, the higher the latency time, was stated. No significant differences were found in PGSI as well as in total volume of obtained eggs, but groups differed significantly in the number of dry eggs and in number of swollen egg. Significant negative correlation between domestication level and number of swollen eggs, i.e., the higher the domestication level, the lower the number of eggs, was detected. The survival rate at the eyed stage was the highest in WS group (60.4 %) and PS group (57.7 %), and was significantly higher than in SPS group (51.8 %). Eggs obtained after CPH stimulation had higher survival rate at the eyed-egg stage (60.3 %) than eggs obtained from the fish stimulated with Ovopel (53.0 %). The data suggest that some form of domestication appeared in ide cultivated for several generations in carp pond.  相似文献   
159.
The aim of this study was to evaluate the effect of hydrogen peroxide, iodine solution (PVP) and methylene blue on eggs disinfection of three ornamental fish species, Danio rerio, Pterophyllum scalare and Gymnocorymbus ternetzi. The main idea was to create conditions to enhance the hatching rates. Eggs of each species were exposed to different concentrations of hydrogen peroxide (5, 10, 15 and 25 mg/L), PVP (0.25, 0.5, 0.75 and 1 mg/L) and methylene blue (0.5 1, 2 and 3 mg/L). The optimal doses ranged between species and chemicals: for G. ternetzi, the concentrations that high enhanced the hatching rate were 1 mg/L for the PVP treatment, 25 mg/L for the hydrogen peroxide treatment and 3 mg/L for methylene blue treatment; for P. scalare, the best results were achieved with 25 mg/L for hydrogen peroxide treatment and 3 mg/L for methylene blue treatment. By contrast, for all the different chemical did not increased the D. rerio hatching rate. Results showed that hydrogen peroxide and methylene blue are the most versatile, effective and safe to use in these species. On the other hand, PVP can be used but with many precautions due to very low safety margin. Results clearly show that the optimal concentration of chemicals for eggs disinfection is fish species dependent and it is completely wrong to extrapolate concentrations between different chemicals and fish species. Our study suggests that P. scalare can be used as a model in study of effectiveness of new chemicals with potential to disinfect water and increase hatching rates.  相似文献   
160.
This study evaluated the effect of increasing levels of monensin sodium (MON) in diets with virginiamycin (VM) on the finishing of feedlot cattle. Two hundred and eighty intact male Nellore cattle (348 ± 32 kg body weight, 22 months) received one of the following five diets: control diet (without additives); diet containing VM (25 mg per kg dry matter) combined with 0 (MON0), 10 (MON10), 20 (MON20) or 30 (MON30) mg MON per kg dry matter. During adaptation (28 days), the MON0 diet increased dietary net energy for maintenance and gain compared to the control diet (= 0.04). The combination of additives linearly reduced dry matter intake, body weight and average daily gain (< 0.01). Considering the total study period (110 days), there was a trend of greater net energy intake for maintenance (= 0.09) and hot carcass weight (= 0.06) for animals fed MON0 compared to the control diet. The combination of additives linearly reduced dry matter intake (= 0.04) and linearly increased gain : feed and dietary net energy for maintenance and gain (< 0.01). The combination of VM with MON at a dose of 30 mg/kg dry matter is recommended for Nellore feedlot cattle because it improves the efficiency of energy utilization.  相似文献   
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