Fluelarver som proteinfoder til økologisk fjerkræ

Fluelarvemel suppleret med levende fluelarver er et godt alternativ til fiskemel i økologisk hønsehold, viser ny forskning fra AU Foulum

Fokus på robusthed i økologisk slagtekyllingeproduktion

Naturlig modstandskraft er vigtig i fremtidens økologiske produktionssystemer for at opfylde markedets krav og forbedre den overordnede produktivitet. Men udviklingen af et robust immunsystem vil sandsynligvis være på bekostning af andre funktioner såsom vækst og reproduktion. I Organic RDD projektet SUMMER har man undersøgt tarmsundhed og immunsystem hos forskellige afstamninger af slagtekyllinger med forskellige vækstpotentialer Deimmunologiske undersøgelser viser, at der er forskel på de basale immunfunktioner mellem afstamningerne. Den afstamning med det laveste vækstpotentiale SU51 ser ud til at have et mere robust immunsystem end den afstamning med det største potentiale JA757

Influence of feeding crimped kernel maize silage on the course of subclinical necrotic enteritis in a broiler disease model

This experiment was carried out with 375 male broilers (Ross 308) from days 1 to 28 to evaluate the influence of crimped kernel maize silage (CKMS) on the manifestation of subclinical necrotic enteritis, microbiota counts, organic acid production and relative weights of gastrointestinal segments. A necrotic enteritis disease model was applied. Birds were allocated into 3 different dietary treatments: a maize-based feed (MBF, control diet), and 2 diets supplemented with 15% (CKMS15) or 30% (CKMS30) of crimped ensiled kernel maize. The disease model involved a 10-time overdose of an attenuated live vaccine against coccidiosis given orally on day 17, followed by oral inoculation of Clostridium perfringens Type A (S48, 108 to 109 bacteria/bird) twice daily on days 18, 19, 20 and 21. Scoring of intestinal lesions was performed on days 22, 23, 25 and 28. Ileal and caecal digesta samples were collected for the quantification of selected bacterial groups and organic acids. The results showed that there was no effect of dietary treatments on small intestinal lesion scores (P > 0.05). Lesions scores peaked on days 23 and 25 and decreased again on day 28 ( 0.05). Lesions scores peaked on days 23 and 25 and decreased again on day 28 (P = 0.001). No effect of age on microbiota counts was observed, but feeding of CKMS30 reduced the number of coliforms in ileal contents (P = 0.01). Dietary treatments did not affect organic acid concentrations in ileum and caeca, but there was an effect of age; butyric acid was higher on days 22, 23 and 25 than on day 28 (P = 0.04). Acetic acid and propionic acid concentrations in caeca were the highest on days 22 and 28 but the lowest on days 23 and 25. Relative gizzard and caeca weights were increased, and relative ileum weights were decreased when birds were fed CKMS30 (

Influence of silvere nanoparticles on Growth and Health of broiler chickens after infection with <em>Campylobacter jejuni</em>

Abstract Background Silver nanoparticles (AgNP) have gained much attention in recent years due to their biomedical applications, especially as antimicrobial agents. AgNP may be used in poultry production as an alternative to the use of antibiotic growth promoter. However, little is known about the impact of oral administration of AgNP on the gut microbiota and the immune system. The aim of the present study was to investigate the effects of AgNP on growth, hematological and immunological profile as well as intestinal microbial composition in broilers challenged with Campylobacter jejuni (C. jejuni). Results AgNP did not affect the intestinal microbial profile of birds. The body weight gain and the relative weights of bursa and spleen were reduced when supplemented with AgNP. There was no difference with respect to packed cell volume. However, the plasma concentrations of IgG and IgM were lower in birds receiving AgNP compared to the non-supplemented control group. The expression of TNF-α and NF-kB at mRNA level was significantly higher in birds receiving AgNP. Conclusions The application of AgNP via the drinking water in the concentration of 50 ppm reduced broiler growth, impaired immune functions and had no antibacterial effect on different intestinal bacterial groups, which may limit the applicability of AgNP against C. jejuni in broiler chickens