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101.
Replacement of fishmeal by soy protein concentrate with taurine supplementation in diets for golden pompano (Trachinotus ovatus) 下载免费PDF全文
Two 7‐week feeding trials were conducted to evaluate the capacity of golden pompano (Trachinotus ovatus) to use soy protein concentrate (SPC) as a dietary fish meal substitute. In trial I, fish were fed with a control diet (C) containing 400 g kg?1 fish meal and other four diets in which the fish meal in diet C was replaced by SPC at 20 (R20), 40 (R40), 60 (R60) and 80% (R80). In trial II, a 3 × 2 design was used, and 40 and 80% of the fish meal in diet C were replaced by SPC, with or without 5 g kg?1 taurine supplementation (six diets, C + T, R40 + T, R80 + T, C, R40 and R80, were formulated). In trial I, no significant difference was found in the feed intake between feeding treatments. The weight gain and nitrogen retention efficiency (NRE) decreased, whereas the feed conversion ratio (FCR) and phosphorus retention efficiency (PRE) increased, with decreasing dietary levels of fish meal. No significant differences were found in the weight gain, FCR and NRE between fish fed diets C and R20, whereas fish fed diets C and R20 had higher weight gain than those fed diets R40, R60 and R80. In trial II, no significant differences were found in the feed intake, weight gain, FCR, NRE and PRE between fish fed diets C + T and C. No significant differences were found in the feed intake, weight gain and NRE between fish fed diets R40 and R40 + T or between fish fed diets R80 and R80 + T. At the end of trial II, no significant differences were found in the condition factor, hepatosomatic index and body composition between fish fed diets C and C + T, or between fish diets R40 and R40 + T, or between fish fed diets R80 and R80 + T, except that fish fed diet R40 had lower body protein content than that of fish fed diet R40 + T. The present study reveals that taurine supplementation can elevate fish meal replacement level by SPC in the golden pompano diets. Fish meal can be reduced from 400 to 320 g kg?1, if fish meal is substituted by SPC without taurine supplementation, and can be further reduced to 240 g kg?1, if fish meal is substituted by SPC with 5 g kg?1 taurine supplementation. 相似文献
102.
Z. Ma P. Zheng H. Guo N. Zhang L. Wang S. Jiang J.G. Qin D. Zhang 《Aquaculture Nutrition》2015,21(5):670-678
Effect of weaning time on the larval performance of golden pompano Trachinotus ovatus was studied in the experimental condition. The same weaning regime started on four different days of posthatch (DPH): 13 DPH (W13), 16 DPH (W16), 19 DPH (W19) and 22 DPH (W22), respectively. Growth, survival, RNA/DNA ratios and mid‐gut cell height of fish were assessed in each weaning regime over time. Growth and survival rates of fish larvae weaned in the W19 and W22 regimes were significantly higher than those in the W13 and W16 regimes. No significant differences were found either between W19 and W22, or between W13 and W16 treatments. Fish showed a decrease in the RNA/DNA ratio in W13, but a trend of increase in W16, W19 and W22. Weaning time significantly affected the mid‐gut cell height in larval golden pompano. On 24 DPH, the mid‐gut cell height of fish in the W13 and W16 treatments was significantly thinner than those in the W19 and W22 treatments. Based on fish growth, survival, RNA/DNA ratio and mid‐gut cell height, weaning can be started on 13 DPH in golden pompano larvae, but we recommend that the best weaning window be 16–22 DPH. These results are supported by histological and nutritional evidence and would guide the weaning process for golden pompano larvae, and offer a useful approach to explore the weaning protocol in larval fish rearing. 相似文献
103.
Phenological shifts may play an important role in the success of invasive species. In the coastal regions of continental Portugal, Acacia longifolia is one of the most widespread invasive plants, but there are significant gaps in our understanding and interpretation of its phenology. This study is the first to investigate the phenological variation of A. longifolia and its association with climate in populations representing a temperature and precipitation gradient in mainland Portugal. The results highlighted significant variations in the vegetative (leaf initiation) and reproductive phenophases (bud formation, flowering and fruiting) among populations. Overall, leafing was observed throughout the year, bud formation occurred between summer and spring, anthesis between late winter and the beginning of spring, and fruiting started in late winter. Most of the reproductive phenophases varied across elevation or latitudinal gradients, with populations that were subjected to more stressful climatic conditions advancing their flowering and fruiting phenophases. The occurrence of each phenophase was strongly associated with the climatic conditions in the previous 5–12 months, suggesting that plants receive their phenological cues well in advance of their phenological response. Among climatic factors, temperature and irradiance were the most significant predictors of the phenological cycle of A. longifolia, but precipitation also exerted a greater influence on budding and flowering of the species. The phenological response of A. longifolia in a variety of sites represents an important step towards understanding how its phenology may react to the projected climate change in the Mediterranean region. 相似文献
104.
Bedu AS Labruyère JJ Thibaud JL Barthélémy I Leperlier D Saunders JH Blot S 《Veterinary radiology & ultrasound》2012,53(5):492-500
Golden retriever and Labrador retriever muscular dystrophy are inherited progressive degenerative myopathies that are used as models of Duchenne muscular dystrophy in man. Thoracic lesions were reported to be the most consistent radiographic finding in golden retriever dogs in a study where radiographs were performed at a single-time point. Muscular dystrophy worsens clinically over time and longitudinal studies in dogs are lacking. Thus our goal was to describe the thoracic abnormalities of golden retriever and Labrador retriever dogs, to determine the timing of first expression and their evolution with time. To this purpose, we retrospectively reviewed 390 monthly radiographic studies of 38 golden retrievers and six Labrador retrievers with muscular dystrophy. The same thoracic lesions were found in both golden and Labrador retrievers. They included, in decreasing frequency, flattened and/or scalloped diaphragmatic shape (43/44), pulmonary hyperinflation (34/44), hiatal hernia (34/44), cranial pectus excavatum (23/44), bronchopneumonia (22/44), and megaesophagus (14/44). The last three lesions were not reported in a previous radiographic study in golden retriever dogs. In all but two dogs the thoracic changes were detected between 4 and 10 months and were persistent or worsened over time. Clinically, muscular dystrophy should be included in the differential diagnosis of dogs with a combination of these thoracic radiographic findings. 相似文献
105.
从神农架金丝猴的粪便中分离出1株益生菌株dlt7a,经鉴定为粪肠球菌。为进一步提高发酵液中dlt7a的活菌数量,对菌株dlt7a的发酵工艺进行优化。通过单因素水平试验,确定dlt7a的最佳培养条件为装液量20%(50mL/250mL),接种量2%,培养基初始pH 6.5。设计Plackett-Burman(PB)试验和响应面试验,找出发酵培养基中影响dlt7a活菌数的主要成分是蔗糖、鱼粉和KH_2PO_4,并优化3种重要成分的含量,确定最优发酵培养基配方为:蔗糖2.55%,鱼粉2.63%,豆粕2.5%,酵母膏0.4%,CaCO_3 1.0%,KCl 0.1%,MgSO_4·7H_2O 0.1%,KH_2PO_4 0.014%。在此条件下培养dlt7a菌株,活菌数可达58.83×108cfu/mL,比优化前提高了46.53%。 相似文献
106.
为探究三七绿紫过渡地上茎黄金分割式紫化与其色素含量纵向变化的关系,用分光光度法检测了云南文山一年生三七植株绿紫过渡地上茎各茎段的叶绿素(Chl)、类胡萝卜素(Car)和总花色苷(TA)的含量。结果表明:从茎顶向茎基,茎段的叶绿素a(Chl a)、b(Chl b)和总叶绿素[Chl(a+b)]含量均表现为"降—升—降三段式"曲线,叶绿素a和b的含量之比(Chl a/b)大致呈一不对称的"双峰"曲线,Car含量表现为"不规则波动—宽V型—阶梯型骤降三段式"曲线,总花色苷含量(TAC)、TA/Chl a、TA/Chl b、TA/Chl(a+b)和TA/(Chl+Car)均表现为单峰曲线,Chl(a+b)/Car大致表现为一"V-W形"曲线。在茎中上部的黄金分割点处,Chl a、Chl b和Chl(a+b)、Chl a/b均出现低值,而TAC、TA/Chl a、TA/Chl b、TA/Chl(a+b)和TA/(Chl+Car)却均出现最高值。在茎基部,Chl、Car和TA含量都急剧下降。不同茎段Chl a、Chl b、Chl(a+b)和Car含量之间的差异均达到极显著水平,而TAC之间的差异仅达到显著水平;此外,不同茎段Chl a、Chl b、Chl(a+b)、Car和TA的含量纵向变化之间呈不同的正相关性。所以,三七绿紫过渡地上茎的紫色源于其TA相对于Chl和Car的含量优势,但Car对茎段紫色的制约效应微小;茎的黄金分割式紫化既取决于茎的TAC,也取决于茎的TA/Chl a、TA/Chl b、TA/Chl(a+b)和TA/(Chl+Car)。 相似文献
107.
108.
D. M. Lurie M. D. Lucroy S. M. Griffey E. Simonson B. R. Madewell 《Veterinary and comparative oncology》2004,2(3):171-175
The boxer breed of dog is at high risk for a variety of neoplasms including lymphoma. In this observational study, tissue sections from boxer dogs with lymphoma were immunostained for T and B lymphocyte distinction, and the results compared with similar studies carried out on lymphoma tissues from temporally selected cohorts of golden retriever and rottweiler dogs. The frequency of T‐cell lymphomas was significantly (P < 0.001 for all comparisons) higher in the boxers than in the rottweilers or golden retrievers. We are unaware of other reports linking immunotype of canine lymphoma with breed; whether other brachycephalic breeds of dogs have a similar preponderance of T‐cell lymphoma awaits further study. 相似文献
109.
110.