Immuno-pathological studies on broiler chicken experimentally infected with Escherichia coli and supplemented with neem (Azadirachta indica) leaf extract

Plant Extract in the Control of Poultry Omphalitis

Bacteria continue to disrupt poultry production and can cause resistant and persistent yolk sac infections to prevention efforts, known as omphalitis, resulting in poultry death. This literature review aims to demonstrate how plant extracts can help combat omphalitis in poultry. The Google Scholar database served as a resource for retrieving pertinent literature covering a wide range of search terms relevant to the scope of the research. The search strategy involved a combination of terms such as antimicrobials, chick embryo, omphalitis, plant extracts, poultry nutrition, and sanitization. The potential of plant extracts in preventing or treating infections in poultry, especially omphalitis, is mainly due to their antibacterial and safety properties. Sanitization and direct delivery of plant extracts to the internal contents of eggs, feed, or water are cutting-edge interventions to reduce the bacterial load in eggs and poultry, minimizing infection rates. For example, these interventions may include advanced treatment technologies or precise delivery systems focused on disease prevention in poultry.

Molecular epidemiological studies on avian pathogenic Escherichia coli associated with septicemia in chickens in India

Bacterial septicemia causes huge economic losses in the poultry industry and there is no systematic research available in India on the connection of various pathogens associated with septicemia. The present molecular epidemiological study was conducted to investigate the association of different bacterial and immunosuppressive viral pathogens in septicemia suspected chickens. A total of 443 chicken carcasses with septicemic conditions from 71 different flocks were included in this study. Heart blood swabs were subjected to bacterial culture for Salmonella spp., Pasteurella multocida, Escherichia coli, and Gallibacterium anatis. Of these 51 flocks tested for E. coli, 49 (96.1%) flocks were found positive. Among flocks tested for Salmonella spp., 2 flocks were found positive. All tested flocks were found negative for G. anatis and P. multocida as well as air sac swabs tested negative for Mycoplasma spp. Bacterial cultural examination revealed that majority of septicemic chickens were found to be infected with E. coli and these E. coli isolates showed the highest resistance to vancomycin (60%), followed by erythromycin (50%) and cefotaxime (38%) and maximum sensitivity to cefotaxime and clavulanic acid combinations (81.5%), followed by chloramphenicol (69.6%) and ertapenem (67.2%). Among the 5 avian pathogenic E. coli (APEC) virulence genes were detected in 36 flocks and highest frequency of iss (100%), followed by ompT or iutA (97.2%), hly (61.1%) and iroN (47.2%) genes. On polymerase chain reaction (PCR) screening, 10.5, 4.5, 52.2, 19.4, 9.0, 4.5, 20.1 and 19.4% of the flocks were positive for G. anatis, Ornithobacterium rhinotracheale, APEC, Salmonella spp., Mycoplasma gallisepticum, Mycoplasma synoviae, chicken infectious anemia virus and Marek's disease virus, respectively. To our knowledge, the present study is first on the etiology of septicemia in chicken flocks in India. The present study infers that the majority of septicemic deaths in broiler chickens less than 8 weeks have been connected with APEC and majority of E. coli isolates are multidrug resistance, suggesting the need for surveillance and intervention to curb the inadvertent use of antibiotics. Although, incidence of G. anatis association with septicemia was reported, still requires a rigorous epidemiological study to determine the actual prevalence. However, more detailed studies encompassing vast geographical area with large sample size and long duration of the studies are necessary to provide a clear picture of the interaction of different pathogens causing septicemia in chicken.

Comparative assessment of the bactericidal effect of nanoparticles of copper oxide, silver, and chitosan-silver against Escherichia coli infection in broilers

Escherichia coli infection is considered one of the most economically important multi-systemic diseases in poultry farms. Several nanoparticles such as silver, chitosan, and copper oxide are known to be highly toxic to several microbes. However, there are no data concerning their success against in vivo experimental E. coli infection in broilers. Therefore, the present study was designed to investigate the bactericidal effect of low doses of CuO-NPs (5 mg/kg bwt), Ag-NPs (0.5 mg/kg bwt), and Ch-Ag NPs (0.5 mg/kg bwt) against E. coli experimental infection in broilers. One hundred chicks were divided into five groups as follows: (1) control; (2) E. coli (4 × 108 CFU/ml) challenged; (3) E. coli +CuO-NPs; (4) E. coli +Ag-NPs; (5) E. coli +Ch-Ag NPs. The challenged untreated group, not NPs treated groups, recorded the lowest weight gain as well as the highest bacterial count and lesion score in all examined organs. The highest liver content of silver was observed in Ag-NPs treated group compared with the Ch-Ag NPs treated group. Our results concluded that Ch-Ag NPs not only had the best antibacterial effects but also acted as a growth promoter in broilers without leaving any residues in edible organs. We recommend using Ch-Ag NPs in broiler farms instead of antibiotics or probiotics.

Dietary supplementation of Neem (Azadirachta indica) leaf extracts improved growth performance and reduced production cost in broilers

Background and Aim

Global trend to remove the antibiotic growth promoter (AGP) from animals contributes to the exploration of successful measures to sustain production and reduces the intestinal diseases in the post-AGP era. Plant extracts, therefore, have been used to improve performance and intestinal health. Here, we conducted a study to evaluate the effects of neem (Azadirachta indica) leaf extracts (NLE) as alternatives to AGPs in broiler chickens.

Materials and Methods

Sixty day-old broiler chicks were assigned to 12-floor pens, each stocked with five birds and divided into three treatment groups of four pens per treatment. The groups were: Negative control, basal diet without additives; positive control, basal diet with antibiotics and vitamins; and NLE treated group, basal diet supplemented with 0.1% aqua extract of neem leaves.

Results

Overall feed intake was significantly (p≤0.05) highest in the positive control. Higher body weight, higher dressing percentage, and lower feed conversion ratio were observed in birds treated with NLE compared to the negative control group (p≤0.05) but not the positive control group (p>0.05). There was no significant variation in hematology between different groups. Furthermore, the economic evaluation indicated that the NLE treatment was found cheaper than control and antibiotic treatment in cost-benefit analysis.

Conclusion

We suggest NLE might be a cheaper alternative to antibiotics in broiler production as indicated by improved body weight and feed efficiency.

Effects of the Dietary Probiotic, Enterococcus faecium NCIMB11181, on the Intestinal Barrier and System Immune Status in Escherichia coli O78-Challenged Broiler Chickens

The effects of Enterococcus faecium on growth, intestinal barrier function, and immune response in Escherichia coli O78-challenged broiler chickens were investigated. Three hundred eight 1-day-old Ross male chickens were randomly assigned into three treatment groups: negative control (C), E. coli O78-infected positive (EP), and E. coli O78-infected with 200 mg/kg E. faecium dietary supplementation (EF). E. faecium significantly increased the body weight on day 10 (P < 0.05) and day 15. Furthermore, these birds had a greater average daily gain compared with the other groups during days 1–10 (P < 0.05). The death rate of the EF chickens dramatically declined. E. faecium supplementation improved the jejunal villus height and the ratio of villus height to crypt depth (P < 0.05) 3 and 7 days post-infection. The mRNA expression of claudin-1 significantly increased by E. faecium (P < 0.05) 3 and 7 days post-infection, and Mucin2 was markedly enhanced (P < 0.05) 3 days post-infection. E. faecium upregulated the mRNA expression of PPAR-γ and IL-10 (P < 0.05) and downregulated that of NF-κB, TLR4, and IL-1β (P < 0.05) in the spleen 3 and 7 days post-infection. Lipopolysaccharide stimulation index was markedly enhanced in the EF group (P < 0.05) 3 days post-infection. The increased liver E. coli number caused by the E. coli O78 challenge was significantly reversed by E. faecium (P < 0.05). E. faecium improved growth and reduced the death rate by regulating the immune response and maintaining the intestinal integrity in E. coli O78-challenged broiler chickens.