enramycin and Poultry-Diseases

The maintenance of integrity of the gastrointestinal tract is an important aspect for animal productivity, since it is able to absorb nutrients more efficiently and serves as a barrier against microorganisms. To control agents detrimental to intestinal integrity, growth-promoting antibiotics (AGP) are used, which reduce the number of toxin-producing microorganisms in the intestinal lumen, acting as anti-inflammatory agents. There is a demand for restriction of use of AGP in animal feed, but there are few studies showing what parameters we should observe to search for alternative additives. The aim of this study was to establish histological parameters that explain the effect of enramycin as growth promoter on intestinal health in broilers challenged with Eimeria and Clostridium perfringens. The zootechnical performance and the histology by I See Inside (ISI) methodology were evaluated on liver and ileum samples. Chickens challenged without AGP have the worst BWG, FCR, and histological ISI score (ISI score 9) in the ileum compared to non-challenged (ISI score 5). The use of enramycin on challenged group significantly minimized the ISI score in the ileum at 21 and 28 d (ISI score 7.4 and 8.0, respectively) compared with the challenged group not fed with enramycin (ISI score 9.2 and 9.9, respectively), associated with reduced lamina propria thickness and inflammatory cell infiltration. We suggest these 2 histological parameters as a standard to compare products for gut health.

Topics: Animal Feed; Animal Nutritional Physiological Phenomena; Animals; Chickens; Clostridium Infections; Clostridium perfringens; Coccidiosis; Diet; Dietary Supplements; Eimeria; Intestines; Male; Peptides; Poultry Diseases; Random Allocation

Specific-pathogen-free laying hens were inoculated intravenously with the G-4260 strain of avian nephritis virus (ANV). The distribution of the virus in organs, histological changes in main organs, the condition of laying, and egg transmission of the virus were examined in them. Over an experimental period of 27 days, no clinical sings were observed. In a chronological study on the distribution of the virus in organs, the virus was recovered from liver, kidney, jejunum, and rectum for 6 days postinoculation (PI). The virus titer in organ emulsion was the highest in the jejunum of all the main organs. The virus was recovered from the kidney for 8 days PI, although it was not so high in this organ. It was not recovered from the ovary or oviduct. Fluorescent antigens were not observed at all in any material. In a pathological examination, some local inflammatory changes were observed only in the kidney. There were no significant changes in the ovary, oviduct, or any other organ. Antibody appeared 10 days PI and was detectable even 27 days PI, although it was not so high in titer. There was no significant difference in the rate of egg-production between the infected and the sham inoculated groups. No virus was isolated from 111 fertile eggs laid by infected hens over a period from 2 to 27 days PI.

Topics: Animals; Anti-Bacterial Agents; Chickens; Disease Susceptibility; Female; Oviposition; Peptides; Picornaviridae; Picornaviridae Infections; Poultry Diseases; Specific Pathogen-Free Organisms