High-resolution Serotyping Reveals Salmonella Surveillance Challenges in the Turkey Industry.

Despite extensive Salmonella controls used at processing, 5.5% of salmonellosis cases are linked to turkey. This study had two objectives: (i) to summarize USDA-FSIS turkey Salmonella verification program data and (ii) to evaluate Salmonella through turkey production and processing of 22 flocks. In objective 1, USDA-FSIS data show the average Salmonella prevalence in ground turkey from 2016 to 2022 was 15.9%, and that the leading serovar changes frequently. For objective 2, bootsocks (n = 22) were collected on-farm right after load-out. At processing, prescald wingtips (n = 6 composites of 10/flock), prechill wingtips (n = 6 composites of 10/flock), mechanically separated turkey (MST; n = 6 bins/flock), and ground turkey (n = 6 bins/flock) were collected. Salmonella prevalence was determined by a commercial qPCR and culture confirmed. In 33.2% of PCR-positive samples, Salmonella was not confirmed by culture, highlighting a discrepancy between molecular and culture detection. On-farm, 8/22 flocks were Salmonella positive, compared to 21 flocks that were positive at one or more processing locations, including 18 flocks that were positive in at least one final product sample. A logistic regression showed higher Salmonella prevalence in prescald (53.8%) than in prechill (18.2%), MST (27.3%) or ground turkey (26.5%). CRISPR-SeroSeq analysis of 148 culture-positive samples detected 18 Salmonella serovars and showed 35.1% of samples contained multiple serovars. In 16 flocks, one or more serovars detected in final products were absent from any upstream samples. Two-thirds of final product samples containing serovar Typhimurium typed as a live-attenuated Typhimurium vaccine strain. Salmonella on-farm and at prescald did not reflect Salmonella observed in final product. These data underscore the complexity of serovar tracking in turkey production and highlight challenges to identify surveillance samples that accurately represent Salmonella in turkey products.

Characterizing the Effect of Campylobacter jejuni Challenge on Growth Performance, Cecal Microbiota, and Cecal Short-Chain Fatty Acid Concentrations in Broilers.

This study aimed to understand the effect of C. jejuni challenge on the cecal microbiota and short-chain fatty acid (SCFA) concentration to form a better understanding of the host-pathogen interaction. Sixty broilers were randomly allocated into two treatments: control and challenge. Each treatment was replicated in six pens with five birds per pen. On day 21, birds in the challenge group were orally gavaged with 1 × 108C. jejuni/mL, while the control group was mock challenged with PBS. The C. jejuni challenge had no effect on body weight, feed intake, and feed conversion ratio compared to the control group. On day 28, the C. jejuni challenge decreased the observed features and Shannon index compared to the control group. On the species level, the C. jejuni challenge decreased (p = 0.02) the relative abundance of Sellimonas intestinalis on day 28 and increased (p = 0.04) the relative abundance of Faecalibacterium sp002160895 on day 35 compared to the control group. The C. jejuni challenge did not change the microbial function and the cecal concentrations of SCFA on days 28 and 35 compared to the control group. In conclusion, C. jejuni might alter the gut microbiota's composition and diversity without significantly compromising broilers' growth.

Cost-effectiveness of Different Diabetic Retinopathy Screening Modalities.

Current screening strategies aimed at detection of diabetic retinopathy (DR) historically have poor compliance, but advancements in technology can enable improved access to care. Nearly 80% of all persons with diabetes live in low- and middle-income countries (LMICs), highlighting the importance of a cost effective screening program. Establishing mechanisms to reach populations with geographic and financial barriers to access is essential to prevent visual disability. Teleretinal programs leverage technology to improve access and reduce cost. The quality of currently employed screening modalities depends on many variables including the instrument used, use of pupillary mydriasis, number of photographic fields, and the qualifications of the photographer and image interpreter. Recent telemedicine and newer technological approaches have been introduced, but data for these technologies is yet limited. We present results of a systematic review of studies evaluating cost-effectiveness of DR screening, and discuss potential relevance for LMICs.

8,8-dialkyldihydroberberines with potent antiprotozoal activity.

Semisynthetic 8,8-dialkyldihydroberberines (8,8-DDBs) were found to possess mid- to low-nanomolar potency against Plasmodium falciparum blood-stage parasites, Leishmania donovani intracellular amastigotes, and Trypanosoma brucei brucei bloodstream forms. For example, 8,8-diethyldihydroberberine chloride (5b) exhibited in vitro IC50 values of 77, 100, and 5.3 nM against these three parasites, respectively. In turn, two 8,8-dialkylcanadines, obtained by reduction of the corresponding 8,8-DDBs, were much less potent against these parasites in vitro. While the natural product berberine is a weak DNA binder, the 8,8-DDBs displayed no affinity for DNA, as assessed by changes in the melting temperature of poly(dA·dT) DNA. Selected 8,8-DDBs showed efficacy in mouse models of visceral leishmaniasis and African trypanosomiasis, with 8,8-dimethyldihydroberberine chloride (5a) reducing liver parasitemia by 46% in L. donovani-infected BALB/c mice when given at an intraperitoneal dose of 10 mg/kg/day for five days. The 8,8-DDBs may thus serve as leads for discovering new antimalarial, antileishmanial, and antitrypanosomal drug candidates.