Effects of broccoli extract and various essential oils on intestinal and faecal microflora and on xenobiotic enzymes and the antioxidant system of piglets

Objective: Since the ban of antibiotics as growth promoting feed additives in the EU in 2006 research in alternatives has gained importance. Phytogenic feed additives represent a heterogenous class of different plant derived substances that are discussed to improve the health of farm animals by direct and indirect antioxidant effects and by influencing microbial eubiosis in the gastrointestinal tract. Consequently our study aimed to investigate the influence of broccoli extract and the essential oils of tur- meric, oregano, thyme and rosemary, as selected individual additives, on intestinal and faecal microflora, on xenobiotic enzymes, and on the antioxidant system of piglets. Methods: 48 four weeks old male weaned piglets were assigned to 6 groups of 8. The piglets were housed individually in stainless steel pens with slatted floor. The control group (Con) was fed a diet without an additive for 4 weeks. The diet of group BE contained 0.15 g/kg sulforaphane in form of a broccoli extract. 535, 282, 373 and 476 mg/kg of the essential oils of turmeric (Cuo), oregano (Oo), thyme (To) and rosemary (Ro) were added to the diets of the remaining 4 groups to stan-dardise supplementation to 150 mg/kg of the oils’ key terpene compounds ar-turmerone, carvacrol, thymol and 1,8-cineole. The composition of bacterial microflora was examined by cultivating samples of jejeunal and colonic mucosa and of faeces under specific conditions. The mRNA expression of xenobiotic and antioxidant enzymes was determined by reversing transcrip- tase real time detection PCR (RT-PCR). Total antioxidant status was assayed using the Trolox Equivalent Antioxidant Capacity (TEAC), and lipid peroxidation was determined by measuring thiobarbioturic acid reactive substances (TBA- RS). Results: Compared to Con piglets all additives positively influenced weight gain and feed conversion in week 1. Over the whole trial period no significant differences in performance parameters existed between the experimental groups. Compared to group Con performance of Ro piglets was, however, slightly impaired. Com- pared to Con piglets Cuo, Oo and To increased the ratio of Lactobacilli:E. coli attached to the jejunal mucosa, whereas BE and Ro impaired this ratio slightly. In contrast in colonic mucosa Ro improved Lactobacilli:E. coli ratio. In faecal samples an improvement of Lactobacilli:E. coli ratio could be analysed for To and Ro. Ro was the only additive that reduced the incidence rate of piglets tested positive for enterotoxic E. coli (ETEC). All additives significantly increased jejunal TEAC and reduced TBA-RS. In the liver BE, Cuo, Oo and To increased TEAC in tendency and Ro significantly. Liver TBA-RS were slightly reduced by all additives compared to Con piglets. Whereas the influence of BE, To and Ro on jejunal TEAC mainly was derived from the induction of xenobiotic and antioxidant enzymes (indirect antioxidant effects), Cuo and Oo influenced TEAC by direct antioxidant effects. Discussion and Conclusions: Our results have shown: That within the labiatae oils Oo and To have the potential to improve performance slightly. That phytogenic substances have a small but not sig- nificant influence on intestinal microflora. That phytogenic feed additives up-regulate the anti- oxidant system of piglets either by direct or by indirect antioxidant effects and that they may thereby improve health status. That within the labiatae oils Oo has a high direct antioxidant potential whereas Ro potently induces xenobiotic and antioxidant enzymes. That broccoli extract is an attractive new phytogenic additive, improving antioxidant status by indirect antioxidant effects. That defined combinations of selected phytogenic substances may produce additive effects. That health promoting effects of phytogenic additives in the future should be studied systematically under the challenge with pathogenic microorganisms or food derived to-xins

Cause and Effect Analysis between Influencing Factors Related to Environmental Conditions, Hunting and Handling Practices and the Initial Microbial Load of Game Carcasses

Environmental, hunting and handling factors affect the microbial load of hunted game and the resulting meat products. The aim of this study was to systematically investigate the influence of several factors on the initial microbial load (IML) of game carcasses during the early hunting chain. Eviscerated roe deer body cavities (n = 24) were investigated in terms of total viable count and the levels of Pseudomonas spp., Lactobacillus spp., Enterobacteriaceae and Escherichia coli (E. coli). Furthermore, a risk analysis based on the obtained original IML data, literature search and a Failure Mode and Effects Analysis (FMEA) was performed. The IML could be explained in a regression model by factors including the higher body weight (BW), damaged gastrointestinal tract by the shot, ambient temperature or rain. The levels of Lactobacillus spp. (p = 0.0472), Enterobacteriaceae (p = 0.0070) and E. coli (p = 0.0015) were lower on the belly flap surface when gloves were used during evisceration. The literature search revealed that studies examining influencing factors (IF) on the IML of game carcasses found contradictory effects of the comparable IF on IML. Potential handling failures may lead to a higher IML of game carcasses during the early hunting chain ranked by FMEA. Several handling practices for game carcasses are recommended, such as ensuring efficient cooling of heavier BW carcasses to limit bacterial growth or eviscerating heavier carcasses before lighter ones

Improved sample treatment protocol for accurate detection of live Salmonella spp. in food samples by viability PCR.

Culture-based detection is still considered as the standard way for detection of Salmonella in foods, although molecular methods, such as viability PCR (vPCR), have been introduced to overcome some disadvantages of traditional culture methods. Despite the success of the vPCR methodology, the problem of false-positive results is a major drawback, especially when applied to environmental samples, hindering the interpretation of the results. To improve the efficiency of vPCR, many approaches have been introduced by several authors during the last years. In the present work, the combination of PEMAX dye, double tube change, and double photo-activation step was established as a strategy to improve vPCR protocol. By combining these approaches, we developed an improved sample treatment protocol able to neutralize DNA signals of up to 5.0×107 dead cells/sample from both pure culture and artificially contaminated food samples. Our results indicate that vPCR can work reliable and has a potential for high throughput detection of live Salmonella cells in food samples, minimizing false-positive signals

Effect of PEMAX on 10⁷ dead <i>Salmonella</i> cells in spiked supernatants of the food enrichment broth (FEB).

<p>Effect of PEMAX on 10⁷ dead <i>Salmonella</i> cells in spiked supernatants of the food enrichment broth (FEB).</p

Effect of PEMAX on serial dilutions of live <i>Salmonella</i> cells in the presence of dead cells.

<p>Serial dilutions of live <i>Salmonella</i> cells (5.0×10⁷ to 5.0×10³ cfu) in the presence of 5.0×10⁷ dead <i>Salmonella</i> cells were treated with 0 μM (white bars) or 100 μM (grey bars) PEMAX followed by real-time PCR. The control samples contains either 5.0×10⁷ live or dead cells (no mixed population). Means, standard deviations (n = 4) and the linear regression equation and R² value of PEMAX treated samples are depicted. * In 3 of 4 dead samples treated with PEMAX no PCR signal were detected, therefore only the PCR signal of 1 sample is indicated in the diagram.</p

The effect of milling method, thermal treatment, and particle size of feed on exterior and interior egg quality in laying hens

Milling method, thermal treatment, and particle size are important variables determining feed production costs, feed intake and digestibility and potentially egg quality in laying hens. Besides the raw material, the energy needed during production has a major impact on the total feed costs and energy saving milling methods such as the roller mill are becoming more used in the feed industry. Diminution of feed is the largest energy cost in layer feed production (DEATON et al., 1989) and the second largest after pelleting in broiler feed production (REECE et al., 1985). Hammer mills and roller mills are commonly used to reduce particle size of grains (AMERAH et al., 2007; KOCH, 2002). The hammer mill is easier to handle and to maintain, but requires more energy than the roller mill (AMERAH et al., 2007). The hammer mill produces more spherical and uniform shaped particles (REECE et al., 1985), whereas the roller mill generates a more uniform particle size (AMERAH et al., 2007) with irregular cubic or rectangular shape (KOCH, 2002). In addition, hammer mills produce a greater amount of fine particles (REECE et al., 1985). Due to the fact that chickens have a preference for larger feed particles (SCHIFFMAN, 1968), the particle size distribution may affect egg quality, as nutrients may not be equally ingested or effectively utilized (TANG et al., 2006). In contrast, the comparison between corn based diets milled with hammer or roller mills showed no effects on bird performance and egg shell breaking strength (DEATON et al., 1989). Interestingly, layers fed with a barley based diet ground by roller mill had higher egg weight compared to the same diet produced by a hammer mill (HAMILTON, 1994). Layers fed a barley based diet ground by roller mill reduced feed intake and egg production as compared to maize and wheat diets, while no differences were observed when a hammer mill was used. Egg quality was not affected by milling methods (PEREZ-BONILLA et al., 2014)

Detection of live <i>Salmonella</i> in artificially contaminated food samples (with live and dead cells) by vPCR method.

<p>Detection of live <i>Salmonella</i> in artificially contaminated food samples (with live and dead cells) by vPCR method.</p

The effects of particle size, milling method, and thermal treatment of feed on performance, apparent ileal digestibility, and pH of the digesta in laying hens

Various milling methods result in different particle size distributions and, in combination with mash and thermal treatment (expandate) of the feed, may have an impact on nutrient digestibility, pH of the digesta and subsequently the performance of an animal. Since this aspect has not been widely considered in laying hens, the objective of the present study was to investigate the effects of milling method, expansion, and particle size of feed on performance, apparent ileal nutrient digestibility, and pH of digesta in laying hens. Twelve variants of the same diet were produced. Four different milling techniques (hammer mill, roller mill, disc mill, and wedge-shaped disc mill) were used to grind the feed cereals. Coarse feed was obtained from all four mills. Additionally, fine feed was obtained from the hammer mill and the roller mill. Each of the six feed variants was offered as mash or expandate, resulting in a total of 12 treatments. The duration of the experimental period was 21 days. A total of 576 layers, each 19 weeks of age, were used in eight replicates. The statistical analysis for the four milling methods and two thermal treatments was performed using a 4 × 2 factorial arrangement. The effect of particle size was investigated using a 2 × 2 × 2 factorial arrangement including the coarse and fine particle sizes that were produced with the hammer mill and the roller mill as well as the mash and expandate. The animal performance and the pH of the digesta were not affected by the treatments. Ileal digestibility of starch was significantly improved by feeding mash compared to expandate (P = 0.013) and by feeding coarse compared to fine feed (P = 0.028). Based on this study, the tested milling methods can be used for the production of feed for laying hens without affecting performance and digestibility of nutrients

Public and private standards for dried culinary herbs and spices—Part II : Production and product standards for ensuring microbiological safety

Dried culinary herbs and spices (DCHS) are minor food components with widespread use. Despite their low water activity, some microorganisms—including pathogenic and toxigenic ones—can survive in DCHS. The addition of microbial contaminated DCHS to ready-to-eat food in combination with improper food storage can pose a serious health risk for the consumer. In the past, several food-borne disease outbreaks were related to microbial contaminated spices. The aim of this study was to provide an overview on (i) spice/herb production standards important for promoting food safety by preventing microbial contaminations, (ii) public and private standards providing microbiological criteria to assess the microbiological safety of DCHS, and (iii) product testing performed by DCHS producing/processing businesses to comply with these standards. For that, a literature search and a survey among herb/spice businesses were conducted. Several good practices and production guidelines specific for the primary production and/or processing of culinary herbs and spices were found. Microbiological criteria specific for DCHS are usually rare, but some national standards (mostly of non-EU member states) as well as recommendations by private bodies could be identified. By EU law, no mandatory microbiological criteria specific for DCHS are laid down. The survey indicated a frequent application of business-to-business agreements. The microbiological quality of DCHS was tested by the survey participants mainly in a routine manner by checking every lot or based on buyer–seller agreements. Risk-based testing was less common, which differed to chemical safety testing. Upon import into the EU, testing appeared to be performed predominantly in a routine manner for the pathogenic bacteria Salmonella spp., sulphite-reducing clostridia (including Clostridium perfringens), Bacillus cereus, and Staphylococcus aureus

Standardised Sampling Approach for Investigating Pathogens or Environmental Chemicals in Wild Game at Community Hunts

Wildlife may host pathogens and chemicals of veterinary and public health relevance, as well as pathogens with significant economic relevance for domestic livestock. In conducting research on the occurrence and distribution of these agents in wildlife, a major challenge is the acquisition of a sufficient number of samples coupled with efficient use of manpower and time. The aim of this article is to present the methodology and output of a sampling approach for game animals, which was implemented from 2017/18 to 2020/21 at drive hunts in Brandenburg, Germany. The central element was a framework agreement with the BImA, whereby federal forest officials and other hunters collected most of the samples during field dressing. Further samples of game carcasses were obtained by scientists during subsequent gathering at a collection point. Altogether, 3185 samples from 938 wild ungulates of four species were obtained for various studies analysing—in this case—food-borne agents in game animals. Sampling was representative and reflected the proportional distribution of ungulate species hunted in Brandenburg. Hunting district and hunting season strongly influenced hunting bag and hence sampling success. This sampling approach was demonstrated to be a suitable basis for monitoring programs, that can be adapted to other regions