Silver and gold nanoparticles as a novel approach to fight Sarcoptic mange in rabbits.

Various kinds of pets have been known to contract the ectoparasite Sarcoptes scabiei. Current acaricides are becoming less effective because of the resistance developed by the mite besides their adverse effects on the general activity and reproductive performance of domestic pets. For this reason, the present study aims to discover a novel and safe approach using silver and gold nanoparticles to fight Sarcoptic mange in rabbits as well as to explain their mechanism of action. 15 pet rabbits with clinical signs of Sarcoptic mange that were confirmed by the microscopic examination were used in our study. All rabbits used in this study were assessed positive for the presence of different developing stages of S. scabiei. Three groups of rabbits (n = 5) were used as follows: group (1) didn't receive any treatment, and group (2 and 3) was treated with either AgNPs or GNPs, respectively. Both nanoparticles were applied daily on the affected skin areas via a dressing and injected subcutaneously once a week for 2 weeks at a dose of 0.5 mg/kg bwt. Our results revealed that all rabbits were severely infested and took a mean score = 3. The skin lesions in rabbits that didn't receive any treatments progressed extensively and took a mean score = of 4. On the other hand, all nanoparticle-treated groups displayed marked improvement in the skin lesion and took an average score of 0-1. All NPs treated groups showed remarkable improvement in the microscopic pictures along with mild iNOS, TNF-α, and Cox-2 expression. Both nanoparticles could downregulate the m-RNA levels of IL-6 and IFγ and upregulate IL-10 and TGF-1ß genes to promote skin healing. Dressing rabbits with both NPs didn't affect either liver and kidney biomarkers or serum Ig levels indicating their safety. Our residual analysis detected AgNPs in the liver of rabbits but did not detect any residues of GNPs in such organs. We recommend using GNPs as an alternative acaricide to fight rabbit mange.

Chitosan coating silver nanoparticles as a promising feed additive in broilers chicken.

The present study aimed to evaluate the potential of chitosan coating silver nanoparticles to enhance the growth performance and immune status of broilers without inducing oxidative stress-related pathological lesions in any organs or leaving residues of silver in the edible parts. Five clusters of Cobb one-day-old chicks (n = 10/group in each replication) were given oral therapy, once a week for 36 days as follows: (1) distilled water, (2, 3) 0.5- and 5 ppm silver nanoparticles (AgNPs), respectively, (4, 5) 0.5- and 5 ppm chitosan/silver nanoconjugates (CS/Ag-NCs), respectively. The results demonstrated a marked elevation in the body weight gain with a decline in the food conversion ratio and marked improvement in feeding and drinking behavior of all nanoparticles treated groups, but higher in CS/Ag-NCs groups than AgNPs groups and control group. In contrast to the 0.5 ppm AgNPs receiving group, the group receiving 5 ppm AgNPs noticed remarkable histological changes in some organs, including the liver, kidneys, spleen, and heart. Moreover, the administration of CS/Ag-NCs at two dosage levels didn't influence any histological changes. The AgNPs groups' antibody titers against the ND and AI viruses were almost identical to those of the control group. Otherwise, CS/Ag-NCs groups recorded the highest antibody titers. Additionally, there was a significant increase in silver content in most edible organs of AgNPs groups at a dosage level of 5 ppm. Otherwise, the coating of AgNPs by CSNPs could decrease the aggregation of silver in the biological organs. Thus, we recommend utilizing 0.5 ppm CS/Ag-NCs in broiler farms to promote their growth performance and strengthen their immune defense.

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.

Ecoepidemiology and Potential Transmission of Vibrio cholerae among Different Environmental Niches: An Upcoming Threat in Egypt.

Cholera is a negative public health event caused by Vibrio cholerae. Although V. cholerae is abundant in natural environments, its pattern and transmission between different niches remain puzzling and interrelated. Our study aimed to investigate the occurrence of nonpathogenic V. cholerae in the natural environment during endemicity periods. It also aimed to highlight the role of molecular ecoepidemiology in mapping the routes of spread, transmission, and prevention of possible future cholera outbreaks. V. cholerae was detected in different aquatic environments, waterfowl, and poultry farms located along the length of the Nile River in Giza, Cairo, and Delta provinces, Egypt. After polymerase chain reaction amplification of the specific target outer membrane gene (Omp W) of suspected isolates, we performed sequence analysis, eventually using phylogenetic tree analysis to illustrate the possible epidemiological relationships between different sequences. Data revealed a significant variation in the physicochemical conditions of the examined Nile districts related to temporal, spatial, and anthropogenic activities. Moreover, data showed an evident association between V. cholerae and the clinically diseased Synodontis schall fish. We found that the environmental distress triggered by the salinity shift and elevated temperature in the Middle Delta of the Nile River affects the pathogenesis of V. cholerae, in addition to the characteristics of fish host inhabiting the Rosetta Branch at Kafr El-Zayat, El-Gharbia province, Egypt. In addition, we noted a significant relationship between V. cholerae and poultry sources that feed on the Nile dikes close to the examined districts. Sequence analysis revealed clustering of the waterfowl and broiler chicken isolates with human and aquatic isolated sequences retrieved from the GenBank databases. From the obtained data, we hypothesized that waterfowl act as a potential vector for the intermediate transmission of cholera. Therefore, continuous monitoring of Nile water quality and mitigation of Nile River pollution, in addition to following good managemental practices (GMPs), general hygienic guidelines, and biosecurity in the field of animal production and industry, might be the way to break this cyclic transmission between human, aquatic, and animal sectors.

Cytotoxicity and Genotoxicity of Copper oxide Nanoparticles in chickens.

Copper oxide nanoparticles (CuO-NPs) are consciously used to control the growth of bacteria, fungi, and algae. Several studies documented the beneficial and hazardous effects of CuO-NPs on human cells and different experimental animals but there are not many studies that report the effect of CuO-NPs in poultry. Therefore, the present study was performed to investigate the dose-dependent effects of copper oxide nanoparticles on the growth performance, immune status, oxidant/antioxidant capacity, DNA status, and histological structures of most edible parts of broiler chickens (muscle, heart, liver, spleen, and kidneys). The experiment was carried out on 90 1-day-old broiler chicks (Cobb 500) which were divided into three experimental groups (n = 30) in three replicates (n = 10). Group 1 was kept as a control group and did not receive copper oxide nanoparticles. Groups 2 and 3 received CuO-NPs by oral gavage at dose 5 mg/kg and 15 mg/kg bwt respectively at 1, 7, 14, 21, 28, and 35 days of the life of the chickens. An increase in the amount of feed intake and weight was recorded every week, and finally, the food conversion ratio (FCR) was calculated. Our results showed dose-dependent increases in malondialdehyde levels, copper contents, DNA fragmentation percent, and microscopic scoring in different examined organs of CuO-NPs-receiving groups associated with a remarkable reduction in weight gain, food conversion ratio, catalase activity, and antibody titer of both New Castle and Avian Influenza viruses. Histopathological alterations were observed in both groups receiving CuO-NPs with some variations in its severity. Our study concluded that CuO-NPs are considered cytotoxic and we recommend not adding them to poultry feed.

The effect of different concentrations of gold nanoparticles on growth performance, toxicopathological and immunological parameters of broiler chickens.

The present study aimed to evaluate what dosage of gold nanoparticles (GNPs) would improve growth performance, antioxidant levels and immune defense in broiler chickens. The experiment was carried out on 90 one-day-old mixbred Cobb chicks. The birds were allocated into three groups with three replicates. Group (1) kept as a negative control. Groups (2) and (3) received 5, 15 ppm GNPs via drinking water weekly for 35 days of chicks' life. Blood samples were collected at 8, 15, 22 and 36 days for oxidative stress evaluations and immunological studies. The birds were slaughtered at the ages of 36 days and thymus, spleen, busa of Fabricius and liver were collected for histopathological description, RT-PCR analysis and DNA fragmentation assay. Our results confirmed that adding of 15ppm GNPs in drinking water were induced remarkable blood oxidative stress damage, histopathological alterations, up-regulation of IL-6, Nrf2 gene expression, and DNA fragmentation in the examined immune organs of the broiler chickens as well as a significant reduction in the antibody titer against Newcastle (ND) and avian influenza (AI) viruses were noticed. On the other hand, the group received 5 ppm GNPs noticed better growth performance with the enhancement of the final food conversion ratio (FCR) without any significant difference in the previous toxicological and immunological parameters compared with the control groups. We suggest that feeding of 5ppm GNPs could improve the antioxidant capacity, immunity and performance in poultry but further food quality assurance tests are required in the future to confirm its safety for people.