Effect of a direct-fed microbial (Primalac) on structure and ultrastructure of small intestine in turkey poults
ABSTRACT The effects of dietary supplementation of the direct-fed microbial (DFM) Primalac in mash or crumbled feed on histological and ultrastructural changes of intestinal mucosa was determined in 2 populations of poults; 1 with and 1 without a Salmonella spp. challenge. Three hundred thirty-six 1-d-old female Large White turkey poults were randomly distributed into 8 treatment groups with 6 replicates of 7 poults in each pen. The poults were placed on 1 of 4 dietary treatments in a 2 x 2 x 2 factorial arrangement (mash or crumble feed, with or without DFM, not-challenged or challenged at 3 d of age). The DFM groups were fed a Primalac-supplemented diet from d 1 until the last day of the experiment (d 21). At 3 d of age, 50% of the poults were challenged with 1 mL of 10(10) cfu/ mL of Salmonella spp. (Salmonella enterica serovar Typhimurium, Salmonella Heidelberg, and Salmonella Kentucky) by oral gavage. The inoculated poults were housed in a separate room from nonchallenged controls. Feed and water were provided ad libitum for all birds. At d 21, 1 poult per pen (total of 6 poults per treatment) was randomly selected and killed humanely by cervical dislocation. After necropsy, the small intestine was removed, and tissue samples from duodenum, jejunum, and ileum were taken for light and electron microscopic evaluation. The DFM birds showed increased goblet cell (GC) numbers, total GC area, GC mean size, mucosal thickness, and a greater number of segmented filamentous bacteria compared with controls. Changes in intestinal morphology as observed in this study support the concept that poultry gut health and function, and ultimately bird performance, can be improved by dietary supplementation with DFM products such as Primalac as used in this study.
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ABSTRACT: The critically endangered New Zealand parrot, the kakapo, is subject to an intensive management regime aiming to maintain bird health and boost population size. Newly hatched kakapo chicks are subject to human intervention and are frequently placed in captivity throughout their formative months. Hand-rearing greatly reduces mortality among juveniles, but the potential long-term impact on the kakapo gut microbiota is uncertain. To track development of the kakapo gut microbiota, faecal samples from healthy, pre-fledged juvenile kakapo, as well as unrelated adults, were analysed using 16S rRNA gene amplicon pyrosequencing. Following the original sampling, juvenile kakapo underwent a period of captivity, so further sampling during and post-captivity aimed to elucidate the impact of captivity on the juvenile gut microbiota. Variation in the faecal microbiota over a year was also investigated, with resampling of the original juvenile population. Amplicon pyrosequencing revealed a juvenile faecal microbiota enriched with particular lactic acid bacteria when compared to the adults, although overall community structure did not differ significantly among kakapo of different ages. Abundance of key OTUs was correlated with antibiotic treatment and captivity, although the importance of these factors could not be proven unequivocally within the bounds of this study. Finally, the microbial community structure of juvenile and adult kakapo changed over time, reinforcing the need for continual monitoring of the microbiota as part of regular health screening.Applied and Environmental Microbiology 05/2014; 80(15). DOI:10.1128/AEM.00975-14 · 3.95 Impact Factor
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ABSTRACT: Birds represent a diverse and evolutionarily successful lineage, occupying a wide range of niches throughout the world. Like all vertebrates, avians harbor diverse communities of microorganisms within their guts, which collectively fulfill important roles in providing the host with nutrition and protection from pathogens. Although many studies have investigated the role of particular microbes in the guts of avian species, there has been no attempt to unify the results of previous, sequence-based studies to examine the factors that shape the avian gut microbiota as a whole. In this study, we present the first meta-analysis of the avian gut microbiota, using 16S rRNA gene sequences obtained from a range of publicly available clone-library and amplicon pyrosequencing data. We investigate community membership and structure, as well as probe the roles of some of the key biological factors that influence the gut microbiota of other vertebrates, such as host phylogeny, location within the gut, diet, and association with humans. Our results indicate that, across avian studies, the microbiota demonstrates a similar phylum-level composition to that of mammals. Host bird species is the most important factor in determining community composition, although sampling site, diet, and captivity status also contribute. These analyses provide a first integrated look at the composition of the avian microbiota, and serve as a foundation for future studies in this area.Frontiers in Microbiology 05/2014; 5:223. DOI:10.3389/fmicb.2014.00223 · 3.94 Impact Factor
- American Journal of Infection Control 06/2011; 39(5). DOI:10.1016/j.ajic.2011.04.069 · 2.33 Impact Factor