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Whole lupin seed meal was evaluated as partial replacement for fishmeal in extruded diets for rainbow trout, with particular emphasis on the effect on growth performance and apparent digestibility coefficient (ADC) of protein, lipids, carbohydrates, and energy. Effect on muscle fatty acid composition was also evaluated. All diets were formulated to be isonitrogenous and isoenergetic and to contain approximately 45% crude protein and 5.5 kcal energy g/diet. Diets were formulated to include whole lupin seed meal at 0, 10, 15, and 20%. Triplicate groups of fish weighing 65.9 ± 15.1 g on average were fed twice a day until apparent satiation during 12 wk. Growth, feed intake, hepatosomatic index, hepatic histology, proximate composition of whole body, and muscular fatty acid profile were determined. Growth and feed utilization were similar in all treatments and whole‐body composition did not vary among treatments. Polyunsaturated fatty acids of the n‐6 and n‐3 series remained constant in muscle as the amount of lupin in diets increased. Furthermore, the ADCs were similar among all diets. These results suggest that inclusion of whole lupin seed meal up to 20% in extruded diets for rainbow trout do not have any negative effect on growth, feed performance, or flesh quality.  相似文献   
2.
The aim of this study was to evaluate the effect of different dose levels of exogenous fibrolytic enzymes (EFE) on in vitro ruminal fermentation kinetics and energy utilization of foliages from three browse trees (Pithecellobium dulce, Heliocarpus velutinus and Guazuma ulmifolia). Mixture of EFE product was added to the leaves of the three browse tree species at three dose levels: 0 (control), 3.5 and 7.0 mg/g of DM. Chemical composition of the foliages, including plant secondary metabolites such as total phenolics (TP), saponins (SAP) and aqueous fraction (AF), was determined. In addition, in vitro assaying of ruminal gas production kinetics was determined for the three browse three foliages treated with EFE. P. dulce had the highest crude protein content (p < 0.05), whereas G. ulmifolia had the highest content of neutral detergent fibre and SAP (p < 0.05) and H. velutinus had the lowest content of TP (p < 0.05). The interaction between tree species and dose level of EFE was significant (p < 0.05) for gas production (GP) at 24 h of incubation, parameters b and c of the accumulated GP curve, short‐chain fatty acids (SCFA) and metabolizable energy (ME). The lowest (p < 0.01) extent of accumulated GP as well as the b and c values occurred in G. ulmifolia at 0 mg EFE/g DM. P. dulce had the highest (p < 0.05) values for ME and SCFA at the highest dose of EFE. Tree species and dose level had significant (p < 0.05) effects on all parameters describing in vitro ruminal fermentation kinetics and energy utilization. Addition of EFE improved the fermentation kinetics of the browse species considered in this study.  相似文献   
3.
In Uganda, a low-income country in east Africa, African swine fever (ASF) is endemic with yearly outbreaks. In the prevailing smallholder subsistence farming systems, farm biosecurity is largely non-existent. Outbreaks of ASF, particularly in smallholder farms, often go unreported, creating significant epidemiological knowledge gaps. The continuous circulation of ASF in smallholder settings also creates biosecurity challenges for larger farms. In this study, an on-going outbreak of ASF in an endemic area was investigated on farm level, including analyses of on-farm environmental virus contamination. The study was carried out on a medium-sized pig farm with 35 adult pigs and 103 piglets or growers at the onset of the outbreak. Within 3 months, all pigs had died or were slaughtered. The study included interviews with farm representatives as well as biological and environmental sampling. ASF was confirmed by the presence of ASF virus (ASFV) genomic material in biological (blood, serum) and environmental (soil, water, feed, manure) samples by real-time PCR. The ASFV-positive biological samples confirmed the clinical assessment and were consistent with known virus characteristics. Most environmental samples were found to be positive. Assessment of farm biosecurity, interviews, and the results from the biological and environmental samples revealed that breaches and non-compliance with biosecurity protocols most likely led to the introduction and within-farm spread of the virus. The information derived from this study provides valuable insight regarding the implementation of biosecurity measures, particularly in endemic areas.  相似文献   
4.
The use of macroalgae as an additional component in animal feeding has been studied. However, information on how it could influence muscle composition of fish body is scarce. This study evaluates four diets with different macroalgae inclusion levels (0%, 1.5%, 3% and 6%) to test the effect on body fatty acid composition of rainbow trout. Tanks with a volume of 600 L were stocked with 60.6 ± 7.9 g fish at a density of 45 individuals tank?1 and fed for 124 days. At the end of the experiment there were not significant differences (P<0.05) in muscle proximate composition among fish fed the different treatments. However, it was determined that inclusion of 3% and 6% of macroalgae meal resulted in a significant increase (P<0.05) of polyunsaturated fatty acids (PUFAs) in muscle. In summary, macroalgae meal in rainbow trout diets do not enhance the quantity of protein and lipid contents at muscle level but an addition of 3–6% might contribute to increase the level of PUFAs, specially EPA, DHA and LIN. Thus, use of macroalgae meal might help to increase lipid quality content in the final product due the beneficial effects of PUFAs for human health.  相似文献   
5.
It is known that some strains of Vibrio parahaemolyticus are responsible for gastroenteric diseases caused by the ingestion of marine organisms contaminated with these bacterial strains. Organic products that show inhibitory activity on the growth of the pathogenic V. parahaemolyticus were extracted from a Vibrio native in the north of Chile. The inhibitory organic products were isolated by reverse phase chromatography and permeation by Sephadex LH20, and were characterized by spectroscopic and spectrometric techniques. The results showed that the prevailing active product is oleic acid, which was compared with standards by gas chromatography and high-performance liquid chromatography (HPLC). These active products might be useful for controlling the proliferation of pathogenic clones of V. parahaemolyticus.  相似文献   
6.
Atlantic salmon (Salmo salar) were fed 6 experimental diets containing three levels of arachidonic acid (ARA) (0.18 g kg?1, 0.28 g kg?1 and 0.63 g kg?1 for low, medium and high levels, respectively) and two levels of vitamin E (150 and 730 mg kg?1 for low and high levels, respectively). At the end of the experimental period, fatty acids in the liver and immunity markers (lysozyme activity, respiratory burst and phagocytic activity) were determined and fish subjected to a challenge test against the salmonid rickettsial syndrome (SRS) pathogen. ARA, vitamin E or their interaction did not exert an effect on fish performance, whereas ARA alone clearly increased the deposition of ARA. Dietary vitamin E only enhanced liver vitamin E deposition, while the interaction of ARA and vitamin E influenced lysozyme activity and EPA/ARA ratio pointing out the effect of both nutrients on the fish immune system and metabolism. Only the medium concentration contributed to reducing mortality when the fish were exposed to the SRS pathogen. In conclusion, different levels of supplementation with ARA and vitamin E in the diet had no effect on productivity, but did have effects on immune markers and cumulative mortality when fish were exposed to the SRS pathogen.  相似文献   
7.
The effect of dietary inclusion of whole grain white lupin (Lupinus albus) on growth performance, histology, muscle fatty acid composition and nutrient digestibility was investigated in an 11‐week growth and a 4‐week digestibility trial with rainbow trout (initial body weight of 54.0 ± 6.2 and 181.9 ± 3.4 g respectively). Four experimental extruded diets were formulated to contain 0%, 30%, 40% and 50% of whole grain lupin and fed to triplicate groups of fish twice a day until apparent satiation. Faeces were collected daily from each digestibility tank by decantation. No significant trends were observed with respect to growth, feed utilization, apparent digestibility coefficients or whole‐body composition (P>0.05). Conversely, increasing levels of dietary lupin led to significant decreases in the Hepatosomatic index (R2=0.75, P<0.05) and slight lipid infiltration into hepatocytes and enterocytes. Muscle fatty acid compositions were slightly affected by the dietary treatment. Polynomial regression of dietary inclusion of lupin and muscle fatty acid concentrations showed an increase in C18:1n‐9, C18:2n‐6 and C18:3n‐3 and a decrease in C20:5n‐3 with increasing dietary lupin level. These results demonstrated that whole grain lupin can be included up to 50% in commercial rainbow trout diets without negative effects.  相似文献   
8.
Despite the importance of certain highly unsaturated fatty acids in osmotic regulation, few studies have been addressed to determine the essential fatty acid requirements for a given species cultured under different salinities. As Galaxias maculatus is a diadromic species, the present study aimed to determine the effect of salinity on the optimum dietary EPA/docosahexaenoic (DHA) ratio for survival and growth during the larval stages. Larvae were fed for 20 days with rotifers containing two different EPA/DHA ratios (low: 0.64 and high: 2.18) at three different salinities (0, 10 and 15 g L?1). The results of this study showed a marked effect of water salinity on larval dietary lipid utilization in G. maculatus larvae. These results suggested that G. maculatus larvae reared at higher salinities may have a higher dietary requirement for DHA, whereas larvae reared at 0‰ showed higher requirements for EPA. The overall results of the present study indicate that even small changes in salinity can determine the optimum dietary EPA/DHA ratio and the quantitative essential fatty requirements of fish. This may have important repercussions and affect the rearing performance of G. maculatus cultured under different salinities.  相似文献   
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