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.
- SourceAvailable from: Youssef A Attia[show abstract] [hide abstract]
ABSTRACT: 1. The effect of different dietary concentrations of inorganic and organic copper on performance and lipid metabolism of White Pekin ducks (WPD) was investigated from 1-49 d of age. A common basal diet was supplemented with 4, 8, 12 and 150 mg/kg of copper (Cu) from inorganic and organic sources to obtain 9 treatments, including 4 concentrations of Cu x two sources, and the unsupplemented control group. Each treatment contained 5 replicates of 9 male ducks each. 2. Supplementation of Cu at 8 mg/kg in inorganic form was adequate for growth of male WPD from 1-56 d of age. Inorganic Cu significantly decreased feed intake and improved feed conversion ratio, compared with the organic form. 3. Plasma Cu significantly increased, while plasma Zn significantly decreased, due to Cu supplementation. Organic Cu showed better efficacy than inorganic for improving liver Cu concentration, Cu excretion and apparent Cu retention. 4. Dietary Cu concentration significantly affected percentage blood and Hgb and abdominal fat deposition. In addition, inorganic Cu increased percentage blood and abdominal fat deposition compared with the organic source. 5. Supplementation of 150 mg/kg of Cu significantly decreased liver and meat lipids, cholesterol, and colour and tenderness of meat; while liver protein and moisture was increased. In addition, dietary 150 mg/kg of Cu supplementation significantly decreased plasma lipids, triglycerides and cholesterol, while increasing plasma AST and ALT. 6. Organic Cu was more potent for decreasing plasma triglycerides than the inorganic source. However, plasma cholesterol was only significantly decreased with the inorganic source of Cu, compared with the unsupplemented control. 7. The organic Cu was safer as a feed additive for WPD, especially at the lower concentrations up to 12 mg; while some mild to moderate changes may be developed at the higher doses, when fed at pharmacological concentrations as a growth promoter.British Poultry Science 02/2012; 53(1):77-88. · 1.15 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: Microbial ecologists are faced with the prob-lem of culturing the previously unculturable intestinal microbiota. Intestinal samples with a viable and variable community cannot be grown in their totality by using current culture condi-tions and media. In some studies, it has been estimated that up to 75% of the diversity of in-testinal microbiota cannot be analyzed by using © 2012 Poultry science association, Inc. SUMMARY the intestinal microbiota are composed of a large diversity of microorganisms. some have been cultured and characterized, but most remain uncultivated and thus uncharacterized. the intestinal microbiota play a significant role in host health, nutrition, physiology, and perfor-mance. In recent studies, researchers have focused on the complex mechanisms involved in host-microbiota symbiosis. Host physiological homeostasis contributes to the stability and composition of the microbiota. Very little is known about microbial competition or metabolism within the intestinal environment, and even less is known about how microbial interactions in-fluence intestinal health and pathogen exclusion. Here we explore factors such as the challenges of studying the intestinal microbiota, how the composition of the microbiota is affected by in-testinal substrates and the host corporeal composition, and whether it is possible to explain the effects of the intestinal microbiota modified by growth promoters. Finally, we discuss the desir-able effects of growth promoters on the microbiota with regard to intestinal health and patho-gen exclusion. Understanding how feed additives affect the intestinal community and the gut environment is the first step in designing strategies to manipulate performance and gut health.
- American Journal of Infection Control - AMER J INFECT CONTROL. 01/2011; 39(5).