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A 12‐week feeding trial was conducted to examine the replacement of fish meal with pet‐grade poultry by‐product meal (PBM‐PG) in the spotted rose snapper Lutjanus guttatus diet. Five experimental diets were formulated to contain graded levels of PBM‐PG at proportion of 250, 500, 75 or 900 g kg?1. The control diet contained sardine fish meal as the main protein source. Four groups of 15 randomly assigned L. guttatus juveniles were fed to satiation 3 times day?1. Except for the fish fed the PBM‐PG90 diet, the growth performance, survival and feed utilization efficiency of the experimental fish were not significantly lower than those of the control fish. The dietary level of PBM‐PG did significantly affect the haematological characteristics (< 0.05). The dietary dry matter and protein apparent digestibility coefficients (ADCs) decreased with increasing dietary PBM‐PG. High values for lipid ADCs were observed in all diets, with significant differences among the dietary treatments. The fish whole‐body protein, moisture, lipid and ash contents were not affected by the inclusion of dietary PBM. These results indicate that high‐quality terrestrial PBM can successfully replace more than half of the marine fish meal protein in the L. guttatus diet.  相似文献   
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环境内分泌干扰物(EDCs),是一类存在于环境介质中并介导生物体内分泌激素的合成、释放、代谢、结合和排泄作用,对其后代产生有害影响的外源性化学物质;因干扰内分泌系统的过程与雌激素类似,故也被称为环境激素[1-2].环境内分泌干扰物分为自然存在和人为合成,人为合成的主要来源于人类广泛的农业和工业活动,如常见的有机氯农药、...  相似文献   
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祝玲  林阿乞  李娟  刘丽  蔡俊鹏  吴忠业 《水产科学》2007,26(10):560-563
从发病的杂交鲍(皱纹盘鲍×盘鲍)稚鲍中共分离27株菌株,并对其分泌胞外产物(包括酪蛋白酶、明胶酶、淀粉酶、脂肪酶、磷脂酶和溶血素)的能力进行了分析。试验结果表明,具有分泌胞外蛋白酶、明胶酶、淀粉酶、脂肪酶、磷脂酶和溶血素能力的菌株分别占总菌株数的81.5%(22/27)、74.1%(20/27)、18.5%(5/27)、0%(0/27)、11.1%(3/27)、29.6%(8/27)。其中,1#、14#菌株具有很强的产胞外蛋白酶能力,而明胶酶的最大分泌者为2#、7#、9#、17#菌株,淀粉酶的为11#、14#菌株,磷脂酶的为11#、15#菌株,溶血素的为菌株10#、21#。此外,10#、11#、15#菌株可同时分泌4种胞外产物,而12#、14#、18#、21#、23#、24#菌株可同时分泌3种胞外产物。综合考虑每一种胞外酶的潜在致病作用,以及菌株分泌多种胞外酶的能力,初步确认11株菌为潜在的致病菌:1#、2#、7#、9#、10#、11#、12#、14#、15#、17#、21#。用API条带法对它们进行了种类鉴定,11株菌中巴斯德氏菌和假单胞菌所占的比例分别为45.5%、27.3%。  相似文献   
36.
Two feeding trials examined the replacement of fishmeal (FM) with poultry by‐product meal (PBM) in the diet of juvenile Sparus aurata. In Feeding trial I (100 days), three diets were formulated, where FM protein was replaced by 50% (PBM50) and 100% (PBM100) PBM, while in Feeding trial II (110 days), four diets were formulated using the same FM control diet, but FM was replaced at lower levels: 25% (PBM25), and 25% (PBM25 + ) and 50% (PBM50 + ) with the supplementation of lysine and methionine amino acids. PBM protein can successfully replace 50% of FM protein in the diet of Saurata without adverse effects on survival, feed intake, growth performance and feed utilization, given that the diet is balanced with lysine and methionine. The proximate composition of body and muscle was unaffected by the diet, but the total FM replacement resulted in reduced lipid and energy contents in fish. A fifty per cent FM replacement by PBM did not affect haematological parameters indicating a good fish health. Similarities in trypsin and chymotrypsin activities with FM‐fed fish suggest a high digestibility of PBM. High dietary levels of PBM reduced the liver gene expression of GH/IGF axis and of cathepsin D suppressing fish growth and modulating the protein turnover.  相似文献   
37.
Our aim is to contribute to the valorization and optimization of a salted-dried seafood product prepared from small-spotted catshark (Scyliorhynus canicula) akin to “litão seco,” the high-priced, traditional dried blackmouth catshark (Galeus melastomus). This work focused on studying the changes in physicochemical and microbiological parameters of S. canicula salted (for 3 h or 24 h) and dried (convection oven for 24 h or tray drier for 3 h). As expected, salting and drying reduced the water content and water activity, while chloride content in fillets increased. Also, significant but distinct changes in color, namely CIE L* and b*, were observed. Total viable counts were significantly reduced in the salted-dried shark, but the later still presented Staphylococcus aureus, though at marginally acceptable, non-hazardous levels. The abundance of yeasts was reduced by 3 log(cfu/g) in samples oven-dried for 24 h but only by 0.8 log after 3 h in the tray-drier. From our results, salted-dried S. canicula has the required physicochemical characteristics and microbiological quality to be apt for human consumption and is a suitable candidate for becoming a traditional seafood product comparable to “litão seco.”  相似文献   
38.
以华盛顿州天使港市当地农产品供应链为例,分析供应链和产品质量的关系,提出充分利用当地农业资源,大规模和中小规模农产品供应链应该互补以提高农产品质量,发展当地经济,提高就业率。  相似文献   
39.
Four wethers were used in a 4 × 4 Latin square design experiment to evaluate in vivo digestibility of total mixed ration (TMR) silage with food by‐products for dairy cows, and the ruminal condition and nitrogen (N) balance were examined. Five by‐products (i.e. potato waste, noodle waste, soybean curd residue, soy sauce cake and green tea waste) were obtained. Four types of TMR silage were used: control (C) containing roughage and commercial concentrate, T1:20% and T1:40% containing the five by‐products replacing 20% and 40% of the commercial concentrate on a dry matter (DM) basis, respectively, and T2:40% containing three by‐products (potato waste, noodle waste and soybean curd residue) replacing 40% of the commercial concentrate on a DM basis. The ingredients were mixed and preserved in oil drum silos for 4 months. The TMR silages showed 4.02–4.44% and 1.75–2.19% for pH and lactic acid contents, respectively. The digestibility of DM and neutral detergent fiber, and total digestible nutrient content were higher (P < 0.05) for T2:40% feeding than for C feeding. Urinary nitrogen excretion tended to be lower (P = 0.07) for T2:40% than for C. The results suggested 40% replacing of commercial concentrate by using the three food by‐products can be most suitable for TMR silage.  相似文献   
40.
In general, there is a lack of scientific documentation of nutritional value of marine by‐products. The bone fraction from fish has been regarded as waste. Due to the high mineral content of fish bones, this material can be well suitable as a natural calcium source. In the present study, apparent calcium absorption of different fish bone sources was tested using growing pigs. The experimental diets consisted of boiled salmon frames, or salmon, saithe or cod bones treated with enzymes. Calcium carbonate (CaCO3) was used as control. The experimental diets were formulated to contain 0.7% total calcium of which the added calcium source to be tested contributed about 71% (study 1) and 86% (study 2). Except for the calcium and phosphorus sources, the animals received similar basal diets. Apparent calcium digestibility coefficient was calculated using yttrium as indicator (both studies) and was based on complete collection of faeces and urine (study 2). The experimental design was parallel and cross‐over in study 1 and study 2, respectively. In study 1, piglets getting salmon bone treated with enzymes had significantly higher calcium absorption than piglets getting boiled fish bone or calcium carbonate. Therefore, in the second study only enzymatically treated fish bones were included. The higher calcium absorption from enzymatically treated salmon bone was also found in study 2, but this time not significant. Calcium from boiled salmon bones in study I, and from enzymatically treated saithe and cod bones in study II were absorbed as well as the calcium carbonate control. The results indicate that fish bones may be a useful and well absorbed calcium source. Due to the high mineral content of the bone fraction, salmon bones can be well suitable as a natural calcium and phosphorus source in, for example, food, feed or as supplement.  相似文献   
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