45 research outputs found
Alternative animal protein sources for aquaculture: a preliminary study on nutritional traits of Mediterranean brocade (Spodoptera littoralis, Boisduval) larvae
In formulating diets for farmed aquatic species, the main ingredi- ent used is fish meal (FM). Due to the growth that aquaculture is experiencing throughout the world, the increasing demand of feeds is resulting in a FM price increase that represents an eco- nomic limit for fish farming. The need to seek protein sources alternative to FM is a matter of great interest. Among others, the use of insect larvae as feed for fish represents an interesting alter- native. The aim of this study was to evaluate the nutritional traits of mediterranean brocade larvae (Spodoptera littoralis Bois.) in view of their possible use as feedstuffs for rainbow trout. A sample of mediterranean brocade larvae (MBL) (VI instar) and one of pupae (MBP) were assayed for fat (EE), ash (ASH) and crude pro- tein (CP) contents by conventional methods. Amino-acidic profile was obtained by HPLC on sample hydrolysates. Relative digestibil- ity of protein (RDP) was estimated by the Lazo (1988) method. Data, expressed on DM basis, were compared with those of a com- mercial feed (CF). The fat content of MBL was lower than that recorded for CF (9.4% vs 13.6%) while MBP showed a very high value (30.3% DM). Ashes in MBL (7.7%) and MBP (6.7%) were lower than in the CF (10.9%). The CP content of MBL (44.3%) was slightly higher than the CF (40.0%) but lower than in MBP (59.1%). The RDP of MBL and MBP were about a half of the value observed in CF (27.2%). Both MBL and MBP showed a lower per- centage of essential amino acids (AA) (35.8%, 36.8%) compared to CF (39.4%) even if the AA profiles were in line with the require- ments found in literature for rainbow trout. In conclusion, these preliminary results suggest that preimaginal stages of S. littoralis may be of interest in fish feeding, though more exhaustive studies have to be performed to fully assess their use as alternative for fish meal
Concentrations of some toxic and trace elements in wild boar (<i>Sus scrofa</i>) organs and tissues in different areas of the Province of Viterbo, Central Italy
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Influence of dietary vitamin E supplementation on cholesterol oxidation and fresh colour in beef aged for 3 and 14 days
The effects of dietary vitamin E supplementation on the susceptibility to lipid oxidation and colour of the Longissimus thoracis (LT) muscle aged in vacuum packaged conditions for 3 or 14 days were studied. For this purpose, Charolais cattle were fed on a diet providing daily 60 mg (control) or 5500 mg of vitamin E per animal (supplemented) for 30 and 60 days before slaughter. Dietary vitamin E supplementation increased the liver vitamin E content, but not in the LT muscle of treated animals. The vitamin supplementation for 30 and 60 days has shown non-consistent effects in reducing cholesterol oxidation products of vacuum-packed aged meat. However, the vitamin E supplementation for 60 days was effective on Lightness stability in LT muscle during vacuum-packed ageing. Overall, from the practical standpoint, this study suggests that supranutritional supplementation up to 60 days may not increase the vitamin E content of Charolais LT muscle giving little, if any, benefits on meat colour and cholesterol oxidation. However, the present study suggests that it would be interesting to determine in which extent specific oxysterols are related to the meat colour and whether colour parameters can be useful for predicting the formation of cholesterol oxidation products along the industrial meat production chain.The effects of dietary vitamin E supplementation on the susceptibility to lipid oxidation and colour
of the Longissimus thoracis (LT) muscle aged in vacuum packaged conditions for 3 or 14 days
were studied. For this purpose, Charolais cattle were fed on a diet providing daily 60mg (control)
or 5500mg of vitamin E per animal (supplemented) for 30 and 60 days before slaughter. Dietary
vitamin E supplementation increased the liver vitamin E content, but not in the LT muscle of
treated animals. The vitamin supplementation for 30 and 60 days has shown non-consistent
effects in reducing cholesterol oxidation products of vacuum-packed aged meat. However, the
vitamin E supplementation for 60 days was effective on Lightness stability in LT muscle during
vacuum-packed ageing. Overall, from the practical standpoint, this study suggests that supranutritional
supplementation up to 60 days may not increase the vitamin E content of Charolais
LT muscle giving little, if any, benefits on meat colour and cholesterol oxidation. However, the
present study suggests that it would be interesting to determine in which extent specific oxysterols
are related to the meat colour and whether colour parameters can be useful for predicting
the formation of cholesterol oxidation products along the industrial meat production chain
Protein hunger of the feed sector: the alternatives offered by the plant world
The expected future demand for highly nutrient animal food products will push the animal production system to search for new sources of high-quality protein feedstuffs. In this scenario, economic and environmental issues will have to be considered while reducing the competition with the plant-based human food chains. Legume grains and some oilseed cakes, by-products from the oil industry, are the main protein sources for ruminants and terrestrial monogastrics such as pigs and poultry. Their relevant role will hold in the next decades, but it is necessary to increase the diversification of sources that can be grown profitably throughout the world, including European countries. Microalgae are a promising source of protein and other nutrients for animal feeding. However, an amazing richness of biologically active substances makes these organisms very interesting as feed ingredients, as their role go far beyond the supply of nutrients. Due to the limited usage of microalgae as human foodstuffs or food ingredients, low competition between microalgae-based feed and food chains is predictable. This review aims to synthesise current knowledge on minor pulses and other protein-rich plant products and microalgae, as alternative ingredients to the conventional animal protein sources, focussing on their production, availability, and nutritional values. Points of strength, weakness, opportunity and threat related to the use of these protein sources in animal feeding are separately analysed through a SWOT approach to underlie future needs in terms of research and/or technological development that could help valorise these nutrient sources as feed ingredients
Quality evaluation of regional forage resources by means of near infrared reflectance spectroscopy
Quality parameters of grassland and pasture samples collected during a three-year period at two environmentally and<br />geographically different areas were analysed by Near Infrared Reflectance Spectroscopy (NIRS). Chemical analysis for<br />crude protein (CP), crude fibre (CF), neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL)<br />and crude ash (ASH) carried out on two-thirds of the samples were used in calibration processes. The remaining onethird<br />of the data was used to validate the best calibrations obtained. Samples selection is discussed. Different math pretreatments<br />(derivative, gap, primary smoothing and secondary smoothing), light scattering correction methods and calibration<br />algorithms were tested to achieve the better predictive performances. We obtained the best results using different<br />regression algorithms to correlate spectral information to chemical data. For CP (R2 = 0.94, SEP=1.3), NDF (R2 =<br />0.95, SEP = 2.14) and ADF (R2 = 0.92, SEP=2.06) Multiple Linear Regression (MLR) models fit chemical data better than<br />Mean Partial Least Square (MPLS) regression. A molecular basis explanation of wavelengths selected was carried out.<br />MPLS models worked well for CF (R2 = 0.93, SEP=1.57), and ASH (R2 = 0.95, SEP=1.17) while poor calibrations were<br />obtained for ADL using both algorithms. To confirm the reliability of the models developed, uncertainties of predictions<br />were compared with findings on nutritional variations and animal performances
Conventional and homeopathic treatments in late pregnant goats: effects on metabolic status and immune response
The study was aimed at assessing the effects of conventional and homeopathic treatments on metabolic status and immune response in late pregnant goats. Administration of an antichetogenic preparation and of Echinacea purpurea in homeopathic dilution did not exert unequivocal effects on metabolic status, but improved some immunological parameters of periparturient goats
Effects of seeding date and seeding rate on yield, proximate composition and total tannins content of two Kabuli chickpea cultivars
Experiments were conducted in open field to assess the effect of seeding season and density on the yield, the chemical composition and the accumulation of total tannins in grains of two chickpea (Cicer arietinum L.) cultivars (Pascià and Sultano). Environmental conditions and genetic factors considerably affected grain yield, nutrient and total tannins content of chickpea seeds, giving a considerable range in its qualitative characteristics. Results confirmed cultivar selection as a central factor when a late autumn-early winter sowing is performed. In effect, a more marked resistance to Ascochyta blight (AB) of Sultano, allowed better agronomic performances when favourable-to-AB climatic conditions occur. Winter sowing appeared to be the best choice in the Mediterranean environment when cultivating to maximise the grain yield (+19%). Spring sowing improved crude protein (+10%) and crude fibre (+8%) content, whereas it did not significantly affect the accumulation of anti-nutrients compounds such as total tannins. The most appropriate seeding rate was 70 seeds m–2, considering that plant density had relatively little effect on the parameters studied