Storage procedures are known to affect the detectability of Clostridium difficile toxins in equine and human feces. We assessed the impact of different storage conditions on the detectability of C. difficile toxins in swine feces. Specimens were inoculated with toxins, 112 ng/g of toxin A (TcdA) and 16 ng/g of toxin B (TcdB) and subjected to the following 3 storage treatments: 4°C, −30°C, repetitive freezing at −30°C and thawing. Toxin determination was assessed at 1, 2, 7, 14, and 21 d with ELISA. A decrease in concentrations of TcdA with time was observed for samples stored at 4°C and repetitive freezing–thawing ( p ≤0.05). On day 14, storage at 4°C resulted in decreased TcdA concentration as opposed to storage at −30°C and repetitive freezing–thawing ( p ≤0.05). On day 21, storage at 4°C resulted in decreased TcdA detectability compared with storage at −30°C ( p ≤0.05). The TcdB concentration was unaffected. These results on toxin detectability in swine feces should be carefully considered in in vitro studies on toxigenic C. difficile. Our results also offer valuable information for microbiologists and veterinarians monitoring the presence of virulent C. difficile in pigs.
Lipids represent a significant energy source in dogs’ diets. Moreover, dogs need some essential fatty acids, such as linoleic and α-linolenic fatty acids, because they are not able to produce them endogenously. This study aimed to evaluate the effect of different dietary lipid sources on faecal microbial populations and activities using different evaluations. Hemp seed oil and swine tallow were tested as lipid supplements in a commercial canned diet at a ratio of 3.5% (HL1 and HL2, respectively). These diets were compared with one rich in starch (HS). Twelve dogs were recruited and equally divided into three groups. Faeces samples at 30 days were used as inoculum and incubated with three different substrates (MOS, inulin, and cellulose) using the in vitro gas production technique. The faecal cell numbers of relevant bacteria and secondary metabolites were analysed (in vivo trial). In vitro evaluation showed that the faeces of the group fed the diet with hemp supplementation had better fermentability despite lower gas production. The in vivo faecal bacterial count showed an increase in Lactobacillus spp. In the HL1 group. Moreover, a higher level of acetate was observed in both evaluations (in vitro and in vivo). These results seem to indicate a significant effect of the dietary fatty acid profile on the faecal microbial population.
Supplementation of pharmacological levels of ZnO (3000 ppm) is widely used for prevention and treatment of diarrhea in weaning piglets and to improve their performance. However, this practice has raised concerns about environmental impact, antimicrobial resistance and nutritional interactions. In this study we compared graded amounts of regular ZnO to equivalent levels of potentiated ZnO (HiZox), added to the piglet’s diets. Our aim was to assess possible advantages of different Zn sources as well as a reduction potential regarding the supplemented dose. Therefore, 1440 piglets (initial BW 10.1 ± 1.55 kg) were randomly allotted to 12 dietary treatments: supplementation of 150, 300, 600, 900, 1500 and 3000 ppm of Zn from regular ZnO or equivalent from HiZox. From day 1 to day 14, piglets were fed dietary treatments accordingly; from day 15 to day 28 all groups received HiZox at 150 ppm. Performance was recorded on d 1, 14 and 28 on trial.The highest (P < 0.001) ADG was observed for piglets fed HiZox at 3000 ppm (247 g/d), while HiZox at 900 ppm and regular ZnO at 3000 ppm presented the same ADG values. The subsequent 14-day levelling to 150 ppm of HiZox led on average to similar body weight gains (ZnO: 7.05 kg; HiZox: 6.93 kg). ADFI increased (P < 0.001) in the first 14 d of trial with increasing Zn levels for both sources. Comparison of ZnO at 3000 ppm and HiZox at 900 ppm showed similar effects on improving fecal consistency during the first two weeks after weaning, which may be due to the more effective surface specific area of HiZox than regular ZnO. In conclusion, HiZox at 900 ppm can be used for improving growth performance and fecal consistency during the first two weeks after weaning as an alternative to the pharmacological level of regular ZnO.
Zusammenfassung
Hintergrund
Laut S3-Leitlinie „Allergieprävention“ (Update 2021) soll bei nicht (voll) gestillten Säuglingen mit erhöhtem Allergierisiko geprüft werden, ob eine Säuglingsnahrung mit nachgewiesener allergiepräventiver Wirksamkeit verfügbar ist. Einige Hersteller bewerben ihre Produkte entsprechend.
Ziel der Arbeit
Der Artikel gibt einen Überblick über die wissenschaftliche Evidenz und internationale Empfehlungen zum Einsatz von hydrolysierter Säuglingsnahrung (sog. hypoallergene [HA-]Nahrung) zur Prävention von atopischen Erkrankungen.
Materialien und Methoden
In medizinischen Datenbanken wurde eine Literaturrecherche (Zeitraum: 2016–2021) zum Nutzen von hydrolysierten Säuglingsnahrungen für die Allergieprävention bei Risikokindern und zu entsprechenden internationalen Leitlinien durchgeführt. Auf dieser Basis wurden die aktuelle Empfehlung der deutschen S3-Leitlinie sowie die Produkte auf dem deutschen Markt eingeordnet.
Ergebnisse
Es gibt keine hinreichenden Belege für einen generellen allergiepräventiven Nutzen von Säuglingsnahrungen mit Proteinhydrolysat bei Säuglingen mit erhöhtem Allergierisiko. Die GINI-Interventionsstudie deutet darauf hin, dass eine der eingesetzten Hydrolysatnahrungen zur Prävention atopischer Dermatitis bei Risikokindern wirksam gewesen sein könnte. Die Ergebnisse können aber, auch angesichts methodischer Schwächen, nicht als alleinige Basis für eine allgemeine Empfehlung zur Verwendung von HA-Nahrung herangezogen werden. Internationale Fachgesellschaften sprechen sich seit einigen Jahren eher gegen eine solche Empfehlung aus.
Diskussion
Für die derzeit in Deutschland vermarkteten Säuglingsnahrungen auf Basis von partiell hydrolysiertem Protein fehlen Wirksamkeitsbelege. Sie können daher nicht zur Allergieprävention empfohlen werden.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.