Non-typhoidal Salmonella (NTS) are among the leading global foodborne pathogens and a significant public health threat. Their occurrence in animal reservoirs and their susceptibilities to commonly used antimicrobials are poorly understood in developing countries. The aim of this study was to estimate the prevalence, determine antimicrobial susceptibility and identify risk factors associated with NTS presence in laying hen farms in Uganda through a cross-sectional study. Pooled faecal samples were collected from 237 laying hen farms and these were analysed for NTS following standard laboratory procedures. In total, 49 farms (20.7%; 95% Confidence interval (CI): 15.6–25.6%) were positive for NTS presence. Altogether, ten Salmonella serotypes were identified among the confirmed 78 isolates, and the predominant serotypes were Salmonella Newport (30.8%), S. Hadar (14.1%), S. Aberdeen (12.8%), S. Heidelberg (12.8%), and S. Bolton (12.8%). Phenotypic antimicrobial resistance was detected in 45(57.7%) of the isolates and the highest resistance was against ciprofloxacin (50.0%) followed by sulphonamides (26.9%) and sulphamethoxazole/trimethoprim (7.7%). Resistance was significantly associated with sampled districts (p = 0.034). Resistance to three or more drugs, multi-drug resistance (MDR) was detected in 12 (15.4%) of the isolates, 9 (75%) of these were from Wakiso district. A multivariable logistic model identified large farm size (OR = 7.0; 95% CI: 2.5–19.8) and the presence of other animal species on the farm (OR = 5.9; 95% CI: 2.1–16.1) as risk factors for NTS prevalence on farms. Having a separate house for birds newly brought to the farms was found to be protective (OR = 0,4; 95% CI: 0.2–0.8). This study has highlighted a high prevalence and diversity of NTS species in laying hen farms in Uganda and identified associated risk factors. In addition, it has demonstrated high levels of antimicrobial resistance in isolates of NTS. This could be because of overuse or misuse of antimicrobials in poultry production. Also importantly, the insights provided in this study justifies a strong case for strengthening One Health practices and this will contribute to the development of NTS control strategies at local, national and international levels.

Non-typhoidal Salmonella (NTS) are foodborne pathogens of global public health significance. The aim of this study was to subtype a collection of 85 NTS originating from poultry farms in Uganda, and to evaluate a subgroup of phenotypically resistant isolates for common antimicrobial resistance genes and associated integrons. All isolates were subtyped by pulsed-field gel electrophoresis (PFGE). Phenotypically resistant isolates (n = 54) were screened by PCR for the most relevant AMR genes corresponding to their phenotypic resistance pattern, and all 54 isolates were screened by PCR for the presence of integron class 1 and 2 encoding genes. These genes are known to commonly encode resistance to ampicillin, tetracycline, ciprofloxacin, trimethoprim, sulfonamide and chloramphenicol. PFGE revealed 15 pulsotypes representing 11 serotypes from 75 isolates, as 10 were non-typable. Thirty one (57.4%) of the 54 resistant isolates carried at least one of the seven genes (bla_TEM-1, cmlA, tetA, qnrS, sul1, dhfrI, dhfrVII) identified by PCR and six (11%) carried class 1 integrons. This study has shown that a diversity of NTS-clones are present in Ugandan poultry farm settings, while at the same time similar NTS-clones occur in different farms and areas. The presence of resistance genes to important antimicrobials used in human and veterinary medicine has been demonstrated, hence the need to strengthen strategies to combat antimicrobial resistance at all levels.

Multi-drug resistant bacteria are seen increasingly and there are gaps in our understanding of the complexity of antimicrobial resistance, partially due to a lack of appropriate statistical tools. This hampers efficient treatment, precludes determining appropriate intervention points and renders prevention very difficult. We re-analysed data from a previous study using additive Bayesian networks. The data contained information on resistances against seven antimicrobials and seven potential risk factors from 86 non-typhoidal Salmonella isolates from laying hens in 46 farms in Uganda. The final graph contained 22 links between risk factors and antimicrobial resistances. Solely ampicillin resistance was linked to the vaccinating person and disposal of dead birds. Systematic associations between ampicillin and sulfamethoxazole/trimethoprim and chloramphenicol, which was also linked to sulfamethoxazole/trimethoprim were detected. Sulfamethoxazole/trimethoprim was also directly linked to ciprofloxacin and trimethoprim. Trimethoprim was linked to sulfonamide and ciprofloxacin, which was also linked to sulfonamide. Tetracycline was solely linked to ciprofloxacin. Although the results needs to be interpreted with caution due to a small data set, additive Bayesian network analysis allowed a description of a number of associations between the risk factors and antimicrobial resistances investigated.

Seroprevalence of Leptospira spp. in cattle is unknown in Uganda. The aim of this study was to estimate the seroprevalence of L. interrogans Icterohaemorrhagiae, Pomona, L. kirschneri Butembo, Grippotyphosa, L. borgpetersenii Nigeria, Hardjo, Wolfii, and Kenya and an overall seroprevalence in cattle from Kole and Mbale districts. Two hundred-seventy five bovine sera from 130 small holder farms from Kole (n = 159) and Mbale (n = 116), collected between January and July 2015, were tested for antibodies against eight Leptospira strains by Microscopic Agglutination Test. A titer of ≥100 was considered seropositive, indicating past exposure. Overall, the seroprevalence was 19.27% (95% CI 14.9–24.5%). Pomona seroprevalence was highest with 9.45% (6.4–13.7%), followed by Kenya 5.09% (2.9–8.6%), Nigeria 4.00% (2.1–7.2%), Wolfii 3.27% (1.6–6.3%), Butembo 1.86% (0.7–4.4%), Hardjo 1.45% (0.5–3.9%), and Icterohaemorragiae and Grippotyphosa with less than 1% positive. Seroprevalence did not differ between districts and gender (p ≥ 0.05). Seven animals had titers ≥400. Cross-reactions or exposure to ≥1 serovar was measured in 43% of serum samples. Seroprevalence of 19% implies exposure of cattle to leptospires.

Infestation of gastrointestinal worms (helminths) contributes significantly to neonatal mortality and reduced growth performance in livestock animals. The present study was conducted to determine the phytochemical composition and the in vitro potency of ethanolic extracts of Tithonia diversifolia and Azadirachta indica on motility inhibition on Haemonchus contortus. Tithonia diversifolia and Azadirachta indica were obtained from farmers in Bulambuli district of Uganda and were treated with 70% ethanol as an extraction solvent. A standard phytochemical procedure was used for qualitative analysis. The in-vitro experiment was conducted using 2.5 mg/ml, 5 mg/ml, 10 mg/ml, and 20 mg/ml for each plant ethanolic extract. Moreover, phosphate buffer saline (PBS) was utilized as the control. Phytochemical analysis revealed the presence of tannins, alkaloid salts, saponins, flavonoids, steroid glycosides, anthracenosides, coumarins, and anthocyanosides in ethanolic extracts. A dosage of 20 mg/l of Tithonia diversifolia and Azadirachta indica indicated motility inhibition of adult Haemonchus contortus after 2.55 hours and 2.1 hours, respectively, compared to the PBS control group. In conclusion, both plant extracts showed anthelmintic activity leading to the mortality of the worms. The ethanolic extracts of Azadirachta indica were faster in causing mortality of Haemonchus contortus than those of Tithonia diversifolia at the same dose rate of 20 mg/ml.