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Literature information on apparent digestibility coefficients (ADC) of dietary nutrients in feedstuff for shrimp species dates to the 1980s though the nutritional consistency of ADC values determined in individual feed ingredients continues under scrutiny. This may be attributed to (a) the large variety of ingredients tested under a single standard methodology (i.e., the partial replacement of a reference diet mix by a fixed proportion of the target ingredient); (b) the complex effects of this dietary strategy upon palatability, digestion/digestibility, and consequently feeding rates; and (c) nutrient leaching of diets during experiments. While the biological phenomenon behind ADC (the so-called "nutrient disappearance" between diet and feces through animal's digestive system) is measured by the difference of nutrient and inert marker content in diet and feces, ADC of a feed ingredients has been mathematically calculated considering the difference in ADC from test (e.g., 30% replacement of a reference diet mash by the target ingredient) versus reference diet ADC and their nutrient content. The present study proposes the determination of individual amino acid ADC of soybean meal (SBM) based on the effect of inclusion of SBM in increasing dietary levels in four practical test diets (5, 10, 15, and 20% SBM, named diets T4, T5, T6, and T7, respectively) upon ADC of test diets. For comparison, the study also included three diets formulated under the standard replacement method (i.e., 10, 20, and 30% replacement of the reference diet mash by SBM, named diets T1, T2, and T3). The feeding trial was carried out under high shrimp performance with automated feeding (20–22 h pellet delivery/day, minimized leaching), and daily feces collection over the trial period (55 days). The estimation of ADC of amino acids in SBM was based on ADC determined in test diets, ADCAA SBM = mean [(ADCAA diet (T4, T5, T6 or T7)/ADCprotein diet (T4, T5, T6 or T7)) × ADCprotein SBM]; diet ADC experimentally determined; and an assigned ADC value of SBM true protein (ADCprotein SBM) estimated by three criteria: effect of increasing inclusion of SBM upon true protein ADC of test diet; additivity of digestible protein supplied by proteinaceous ingredients composing test diets T4 to T7; literature values and author's experience. Results by the new proposed method showed SBM ADC values between 76 and 88% for indispensable amino acids and contrasted with values obtained by applying the conventional replacement method at 30% inclusion of SBM into a reference diet (ADCAA: 87–96%). It was also checked either the improvement or reduction of certain individual amino acid ADC with increasing SBM inclusion level in diets. In conclusion, the new proposed methodology produced reduced and more realistic ADC values of amino acids compared to the conventional method of ingredient replacement into a reference diet at one fixed level. This new methodology for ADC determination is not intended to become an unquestionable reference but rather to offer an alternative view for more realistic values of ADC of feed ingredients for farmed shrimp. [ABSTRACT FROM AUTHOR]

The production of insects on an industrial scale has attracted the attention of the research and agricultural industry as novel protein sources. To detect the presence of Gryllodes sigillatus (GS) in feed and food, a real-time PCR method based on the mitochondrial cytochrome b (CYB) gene is proposed by this study. Forty DNA samples of animal and plant origin were used to confirm the specificity of the qPCR system. The detection method's performance was evaluated on different processed GS matrices including native GS (UnGS) and different commercial products: crunchy roasted samples (RoGS), insect meal mixtures (ACGS) and energetic snacks containing GS (GSS). Data on sequencing were aligned with the reference gene to confirm the PCR products. The regression curve (y = −3.394 x + 42.521; R2 = 0.994, d.f. 14) between Ct values and Log DNA concentrations of Gryllodes sigillatus resulted in an efficiency of 96.4%. The severity of the technological processing treatments and the matrix structure affected the intensity of the PCR signal with the same amount of insect DNA as observed by different y-intercepts of the three-regression lines for RoGS, ACGS, and GSS. The real-time PCR method resulted in robust and sensitive outcomes able to detect low amounts of GS DNA (5 g/100 g) in a complex matrix, making it suitable for detecting the presence or absence of labeled Gryllodes sigillatus material both in feed and food. [ABSTRACT FROM AUTHOR]

The analysis of feed composition in terms of ingredients is addressed by Regulation (EC) 767/2009 and is important for detecting economic fraud and for monitoring feed safety. Within the framework of the EU project Feed-code, we developed and internally validated a modular assay, relying on intron polymorphism, for the complete qualitative analysis of the botanical composition of feed and the quantitative determination of six target plant species. Main performance parameters of each module, such as applicability, repeatability, specificity, and limit of detection, were evaluated. The whole assay was applied to a set of feed-like samples and results were in agreement with the expected composition. Application to a large set of compound feed and individual raw materials revealed the occurrence of botanical impurities. When compared with microscopic analysis, the proposed method gave more reliable results. We conclude that the Feed-code prototype, readily upgradable to include more plant species, is worthy of consideration for a full validation through a collaborative trial. [ABSTRACT FROM AUTHOR]

High-resolution time-of-flight mass spectrometry combined with high performance liquid chromatography is proposed for the detection and determination of 25 mycotoxins and 8 food additives (coccidiostats) in animal feed, using simplified and rapid sample preparation. We developed a procedure for the identification and determination of analytes by the standard addition method. The lower limit of the analytical range is 1 (400) µg/kg for mycotoxins; the analytical range for coccidiostats in feed is 10-200 mg/kg. The relative standard deviation of the results does not exceed 10%. The analysis time is 0.5-1 h. [ABSTRACT FROM AUTHOR]

The availability of robust methods for the species-specific detection of meat and bone meal (MBM) in compound feedingstuffs is an important prerequisite to enforce current and upcoming European legislation on the use of processed animal proteins in animal nutrition. Among possible methods, those based on DNA turned out to be a reliable tool for this aim, since DNA is a quite thermostable molecule able to resist severe heat treatments applied in the manufacturing of animal meals. The application of such methods by control laboratories implies that the method has been validated including an assessment of its robustness. Successful transferability between laboratories is considered an important robustness criterion of the method. However, corresponding guidelines regarding the design of such a study relevant to this field are missing. Here, we demonstrate the feasibility of an alternative concept that was applied to check for the transferability of a qualitative assay for the detection of banned MBM in feedingstuffs at trace level based on real-time PCR. The concept was based on an experimental nested design applying analysis of variance (ANOVA) that was conducted independently in two laboratories and which allows for establishing major factors influencing the result of analysis. Statistical assessment of the results confirmed the importance of the DNA extraction/purification step utilised, whereas the PCR step turned out to be a minor factor regarding the overall variability of the results. Furthermore, blind samples comprised of compound feed adulterated with MBM at 0.1 % and blank compound feed were correctly classified as "positive" or "negative" samples, thus confirming fitness of purpose for the method. This approach can be of interest for other research groups working in the development of real-time PCR methods and in their use by control laboratories. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

This research developed a simple and not expensive DNA method for the qualitative identification of plant raw materials used as feed mixtures. Specific simple sequence tagged (STS) markers were developed to detect faba bean (Lectin A gene), field pea (Convicilin A gene), grain sorghum (UDP-glucosyltransferase gene) and barley (Hordoindoline-a gene), whereas identification of durum and common wheat (lipid transfer protein gene), soybean (Gly m Bd 30K allergen gene) and maize (invertase gene) was carried out using markers available from the literature. Cross-reactivity of the primer pairs was also checked against oat, rye, kidney bean and lentil. The method was effectively applied to the analysis of flour mixtures and extruded feedstuff. It could be included in traceability and certification of animal feeding systems within high quality animal production chains which are strictly related to the production area by the valorisation of locally grown raw materials. [ABSTRACT FROM AUTHOR]

Grain samples from a combined intermediate and advanced stage barley breeding trial series, grown at two sites in two consecutive years were assessed for detailed grain quality and ruminant feed quality. The results indicated that there were significant genetic and environmental effects for “feed” traits as measured using grain hardness, acid detergent fibre (ADF), starch and in-sacco dry matter digestibility (ISDMD) assays. In addition, there was strong genotypic discrimination for the regressed feed performance traits, namely Net Energy (NE) and Average Daily Gain (ADG). There was considerable variation in genetic correlations for all traits based on variance from the cultivars used, sites or laboratory processing effects. There was a high level of heritability ranging from 89% to 88% for retention, 60% to 80% for protein and 56% to 68% for ADF. However, there were only low to moderate levels of heritability for the feed traits, with starch 30–39%, ISDMD 55–63%, ADF 56–68%, particle size 47–73%, 31–48% NE and ADG 44–51%. These results suggest that there were real differences in the feed performance of barleys and that selection for cattle feed quality is potentially a viable option for breeding programs. [ABSTRACT FROM AUTHOR]

The use of β-agonists as growth promoters in cattle breeding is forbidden in many countries for reasons of fair trade and consumer protection. In recent years the use of liquid chromatography (LC) tandem mass spectrometry (MS/MS) has been shown to be the method of choice for the control of β-agonists. In this study an LC-MS/MS multiresidue analysis method is presented for trace analysis of 22 β-agonists. A truly generic concept has been designed based on mixed-mode solid-phase extraction and positive electrospray ionisation LC-MS/MS operated in the multiple reaction monitoring mode. This method allows application to a wide variety of sample matrices such as urine, feed and hair, following minor modifications to the analysis procedure only. The method features fit-for-purpose sensitivity in urine as shown by CCα and CCβ values of less than 0.2 and less than 0.5 μg/l respectively, for all β-agonists studied (terbutaline and reproterol, less than 0.3 and less than 1.0 respectively). Similar but semiquantitative application to feed and hair showed CCβ values of less than 10.0 and less than 5.0 μg/kg, respectively. A further simplification and improvement is demonstrated using Ultra Performance LC (UPLC™) and fast-switching MS/MS. The successful validation of this method following the latest EU requirements and its application to real samples demonstrate that a new versatile tool has been achieved for veterinary control of β-agonists. [ABSTRACT FROM AUTHOR]

In this paper we present a polymerase chain reaction (PCR)-based method for detecting meat and bone meal (MBM) in compound feedingstuffs. By choosing adequate DNA targets from an appropriate localisation in the genome, the real-time PCR method developed here proved to be robust to severe heat treatment of the MBM, showing high sensitivity in the detection of MBM. The method developed here permits the specific detection of processed pig and cattle materials treated at 134 °C in various feed matrices down to a limit of detection of about 0.1%. This technique has also been successfully applied to well-characterised MBM samples heated to as high as 141 °C, as well as to various blind feed samples with very low MBM contents. Finally, the method also passed several official European ring trials. [ABSTRACT FROM AUTHOR]

Microbial colonisation of the gastrointestinal tract of newly hatched chicks starts at hatch, seeded from the immediate hatching environment, and quickly results in dense colonisation. The role of ecological factors in gut colonisation has been extensively investigated, as well as the role of micro- and macronutrients in supporting and selecting for bacterial species highly adapted for utilising those nutrients. However, the microbial community contained in poultry feed and its influence on colonisation and maturation of gut microbiota has not been directly addressed. In this study, we compared the microbiota found in poultry feed, with the microbiota of ileum, cecum and excreta, to identify substantial overlap in core microbiotas of the compared groups. We then investigated the microbiota present in raw feedstuffs: meat and bone meal, wheat, corn, canola, barley, soybean, millrun, sorghum, poultry oil, oats, limestone and bloodmeal from four geographically distinct feedstuff suppliers. Each of the feedstuffs had diverse microbial communities. The meat and bone meal and bloodmeal samples had the most complex and distinct microbial populations. There was substantial overlap in the phylogenetic composition found in the grain and seed samples: barley, canola, corn, millrun, oats, sorghum, soybean meal and wheat. Issues related to methodology, viability of microbial communities in the gut and feed, and the implications for biosecurity are discussed. [ABSTRACT FROM AUTHOR]