2,500 research outputs found
The effect of bone choice on quantification of mineralization in broiler chickens up to 6 weeks of age
An experiment was conducted to assess the most appropriate bone type for measuring bone mineralization in male broiler chicks up to 42 d. A total of 72 male broilers were raised in 0.64 m2 pens on a litter floor. The study design included 2 dietary treatments (Control and Low) containing differing levels of total phosphorus (7.8 and 4.4 g/kg for Control and Low diets respectively) and calcium (22.7 and 13.1 g/kg for Control and Low diets respectively) with each fed to 6 replicate pens of 6 birds. Each wk, 6 birds per diet were euthanized and leg bones removed to measure ash percentage. Foot, toe, tibia, and femur ash were compared using the mean of both legs from each bird, via t-tests to separate Control and Low diets. At the end of wk 1, diets could not be separated using any of the bone ash measures. From wk 2 to wk 5, both tibia and foot ash differentiated between the Control and Low diets, and tibia continued to show significant differences between the diets into wk 6. Femur ash did not show any dietary differences until wk 3, but then showed significant differences between the diets until wk 6. Toe ash only differentiated between diets at wk 2, and variation both within and between birds was high, particularly with younger birds. These results suggest that bird age has implications when choosing a bone for assessing possible differences in dietary phosphorus and calcium uptake. Femur ash may be more appropriate for showing differences in broilers aged 6 wk and older. Foot ash provides a comparable alternative to tibia ash in birds aged 2 to 5 wk of age, providing a labor- and time-saving alternative
Influence of Grow‐Out Feed Fatty Acid Composition on Finishing Success in Nile Tilapia
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Oxidative properties of Moringa oleifera kernel oil from different extraction methods during storage
BACKGROUND
Moringa oleifera (MO) kernel oil is categorized as high‐oleic oil which resembles olive oil. However, different from olive, MO trees are largely available in most subtropical and tropical countries. Therefore, in these countries, the benefits of oleic acid can be obtained at a cheaper price through consumption of MO kernel oil. This study reports on the effect of different extraction methods on oxidative properties of MO kernel oil during storage for 140 days at 13 0C, 25 0C, and 37 0C.
RESULTS
All aqueous enzymatic extraction (AEE)‐based methods generally resulted in oil with better oxidative properties and higher tocopherol retention than the use of solvent. Prior to AEE, boiling pre‐treatment deactivated the hydrolytic enzymes and preserved the oil quality. In contrast, high pressure processing (HPP) pre‐treatment accelerated hydrolytic reaction and resulted in higher free fatty acids after 140 days at all temperatures. No significant changes were detected in the oils' iodine values and fatty acid compositions. The tocopherol contents decreased significantly at both 13 0C and 25 0C after 60 days in the oil from SE method, and after 120 days in oils from AEE‐based methods.
CONCLUSION
These findings are significant in highlighting the extraction method resulting in crude MO kernel oil with greatest oxidative stability in the storage conditions tested. Subsequently, the suitable storage condition of the oil prior to refining can be determined. Further studies are recommended in determining the suitable refining processes and parameters for the MO kernel oil prior to application in variety food products
Potential use of high levels of vegetal proteins in diets for market-sized gilthead sea bream (Sparus aurata)
[EN] The effect of partial or total dietary substitution of fishmeal (FM)
by vegetal protein sources on growth and feed efficiency was
carried out in on-growing gilthead sea bream (mean initial weight
131 g). The Control diet (FM 100) contained FM as the primary
protein source, while in Diets FM 25 and FM 0 the FM protein was
replaced at 75% and 100%, respectively, by a vegetable protein
mixture consisting of wheat gluten, soybean meal, rapeseed meal
and crystalline amino acids. Diets FM 25 and FM 0 also contained
krill meal at 47 g/kg in order to improve palatability. At the end of
the trial (after 158 d), fish survival was above 90%. Final weight
and the specific growth rate were statistically lower in fish fed the
Control diet (361 g and 0.64%/d), compared with 390–396 g and
0.69–0.70%/d after feeding vegetal diets. No significant differences
were found regarding feed intake and feed conversion ratio. The
digestibility of protein and amino acids (determined with chromium
oxide as indicator) was similar in all diets. The blood parameters
were not significantly affected by treatments. The activity
of trypsin and pepsin was significantly reduced after feeding Diet
FM 0. In the distal intestine, the villi length in fish fed Diet FM 25
was significantly longer and the intestine of the fish fed the FM
100 diet showed a smaller number of goblet cells. In conclusion, a
total FM substitution by a vegetal mix supplemented with synthetic
amino acids in on-growing sea bream is feasible.This work was supported by the Vicerrectorat d'Investigacio, Innovacio i Transferencia - Universitat Politecnica de Valencia, Project Name: Aquaculture feed without fishmeal (SP20120603). URLs of funder:http://www.upv.es/entidades/VIIT/info/indexnormalc.htm. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Monge-Ortiz, R.; Martínez-Llorens, S.; Marquez, L.; Moyano-Lopez, FJ.; Jover Cerdá, M.; Tomas-Vidal, A. (2016). Potential use of high levels of vegetal proteins in diets for market-sized gilthead sea bream (Sparus aurata). Archives of Animal Nutrition. 70(2):155-172. https://doi.org/10.1080/1745039X.2016.1141743S15517270
The Effect of a Mycotoxin Deactivation Product on Growth of Juvenile Rainbow Trout Fed Distillers Dried Grains
Distillers dried grains (DDG) with solubles (DDGS) is a product that has shown potential as a protein source for some fish species, but high inclusion rates of DDGS have not always been successfully achieved for Rainbow Trout Oncorhynchus mykiss. Our objective was to determine whether inclusion of a mycotoxin deactivation product (Biofix Plus) could improve the ability of high-protein DDG (HPDDG) to replace a portion of the fish meal in diets for Rainbow Trout. The 2 × 2 factorial feeding trial examined protein source (menhaden fish meal [MFM] or HPDDG) with or without Biofix Plus. A control diet (42% digestible protein, 20% crude lipid, 25% MFM) was compared to a test diet in which HPDDG replaced 12% of the total MFM on a digestible-protein basis (24% HPDDG inclusion). Diets were fed to juvenile Rainbow Trout (initial weight: mean ± SE = 30.5 ± 1.6 g) in four replicate tanks per treatment for 9 weeks in a 15°C recirculating system. At the conclusion of the feeding trial, we observed no negative effects of fish meal replacement on growth or feed conversion ratio; no benefit of Biofix Plus supplementation was observed. These data indicate that when Rainbow Trout diets containing a high-quality DDGS product are balanced for digestible protein, lysine, methionine, and threonine, dietary fish meal levels can be successfully reduced to 13% without compromising growth and without the need for mycotoxin deactivator inclusion
Chemical composition, palatability and physical characteristics of venison from farmed deer
The quality of venison from farmed deer were evaluated based on chemical composition, palatability scores, W-B shear force, ultimate pH, and color. The samples of venison were derived from javan rusa (Cervus timorensis russa), moluccan rusa (Cervus timorensis moluccensis), sambar (Cervus unicolor brookei), fallow (Dama dama) and imported red deer (Cervus elaphus). Moluccan rusa and red deer were fed grass. Javan rusa, sambar and fallow deer were fed concentrate. The venison obtained from grazing deer (grass-fed) gave higher moisture content (75.3%) than concentrate-fed or confinement-raised deer (74.4%) and imported venison (70.62%). Fat content in venison shows some differences between muscles and species. The concentrate-fed animals had a higher (P 0.05) palatability scores than grass-fed venison. Feeding regimens (grass-fed vs. concentrate-fed) significantly (P < 0.05) influenced fat composition in the venison of farmed deer in this study
Inclusion of alternative marine by-products in aquafeeds with different levels of plant-based sources for on-growing gilthead sea bream (Sparus aurata, L.): effects on digestibility, amino acid retention, ammonia excretion and enzyme activity
[EN] The search for new sustainable aquafeeds for the species with greater economic importance, such as the gilthead sea bream in Europe, is one of the main challenges in the aquaculture sector. The present work tested fishmeal replacement by a mixture of plant meals at different levels, as well as the use of marine by-products with attractant properties and high-quality protein in high plant protein diets. In order to do that, effects on growth and biometric parameters, digestibility, amino acid retention, excreted ammonia and proteases and amylase activity were assessed, using six different diets: FM100 (100% of protein provided by fishmeal), FM50 (50% of replacement), FM25 (75% of replacement) and FM0 (100% of replacement), but also FM25+ (75% of replacement and 15% of squid and krill meal inclusion), and FM0+ (100% of replacement and 15% of squid and krill meal inclusion). In group FM0, a clear impact of dietary changes was observed on growth, survival and ammonia excretion. Amino acid retention in group FM0+ was also significantly affected, which can be explained by the limited content of certain amino acids in this diet. On the other hand, no significant differences were observed in most biometric parameters or in enzyme activity. In conclusion, complete fishmeal replacement can be achieved by using a mixture of plant-based sources, but supplementation with complementary marine ingredients can prevent detrimental effects on growth, survival, nutritional parameters and protein metabolism.This work was supported by the Vicerrectorat d'Investigacio, Innovacio i Transferencia of the Universitat Politecnica de Valencia, within the project Aquaculture feed without fishmeal (SP20120603). URLs of funder: http://www.upv.es/entidades/VIIT/info/indexnormalc.htm. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Estruch-Cucarella, G.; Tomas-Vidal, A.; El Nokrashy, AM.; Monge-Ortiz, R.; Godoy-Olmos, S.; Jover Cerda, M.; Martínez-Llorens, S. (2018). Inclusion of alternative marine by-products in aquafeeds with different levels of plant-based sources for on-growing gilthead sea bream (Sparus aurata, L.): effects on digestibility, amino
acid retention, ammonia excretion and enzyme activity. Archives of Animal Nutrition. 72(4):321-329. https://doi.org/10.1080/1745039X.2018.1472408S32132972
Production of seafood flavour formulations from enzymatic hydrolysates of fish by-products
© 2015 Published by Elsevier Ltd. Amino acid-rich extracts derived from fish by-products were utilised to generate flavour model systems with added glucose and/or fish oil. Combination of endo and exo peptidases resulted in the most marked increased in free amino acids, particularly for leucine, lysine and glutamic acid (48.3 ± 3.4 to 1423.4 ± 59.6, 43.3 ± 1.2 to 1485.4 ± 25.6 and 143.6 ± 21.7 to 980.9 ± 63.6 μg/g respectively).Main volatile products formed after heating the systems were 4-heptenal, 2,4-heptadienal, and some pyrazines. Increased concentrations of 1-octen-3-ol or 1-hepten-4-ol were also observed in the heated systems compared to the controls. All of these volatile compounds have been identified among the volatile profile of cooked seafood. Conversion of low value fish derived materials such as fish powder, into more valuable products such as flavour precursors and subsequently flavour compounds might be a commercially viable proposition for the fish industry
The Effect of a Mycotoxin Deactivation Product on Growth of Juvenile Rainbow Trout Fed Distillers Dried Grains
Analysis of dietary fibre of boiled and canned legumes commonly consumed in the United Kingdom
The use of different analytical methods to measure the dietary fibre content of foods complicates the interpretation of epidemiological studies. The aim of this study was to determine the total (TDF) and insoluble (IDF) fibre content of 14 boiled and canned legumes commonly consumed in the UK using the Association of Official Analytical Chemists (AOAC) enzymatic gravimetric method. The fibre values obtained were compared to non-starch polysaccharide (NSP) values. The results showed that mean values for TDF (2.7–11.2 g/100 g) were higher than NSP (2.6–6.7 g/100 g), with a mean NSP:TDF ratio of 1:1.43. TDF was correlated with NSP (r = 0.6; p = 0.02). Canning significantly reduced TDF and IDF by an average of 30% and 26% compared to boiling respectively. However, IDF represented at least 60% of the TDF in both boiled and canned samples. In conclusion, fibre values are affected by the processing and analytical method used
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