Toxoplasma gondii is a zoonotic parasite of public health importance, and poultry serve as intermediate hosts and potential indicators of environmental contamination. In Africa, exposure may be influenced by free-range production systems and contact with environments contaminated by felid faeces. Poultry may also contribute to foodborne transmission when infected meat is consumed raw or inadequately cooked. However, evidence on the prevalence of T. gondii infection in African poultry remains fragmented, and previous reviews of food-animal toxoplasmosis have not specifically synthesised poultry prevalence estimates and associated risk factors. This study aimed to estimate the pooled prevalence of T. gondii infection in poultry across Africa, explore sources of between-study heterogeneity, and assess associated risk factors. Following the PRISMA 2020 guidelines, PubMed, Web of Science, Scopus and African Journals Online (AJOL) were searched for studies published between 1 January 2000 and 30 April 2026. Twenty-one studies comprising 37 study arms and 5,580 poultry from 14 African countries were included. The pooled prevalence of T. gondii infection was 29.0
Yeast cultures and exogenous enzymes are widely used as feed additives in ruminant nutrition, particularly in dairy cattle, due to their beneficial effects on rumen fermentation, nutrient degradability, and animal performance. However, information on their application in buffalo nutrition remains limited, and most available knowledge is extrapolated from studies conducted in cattle. Therefore, the present study aimed to evaluate the combined effects of yeast cells and enzymes on lactating multiparous buffaloes’ performance, as well as their influence on ruminal fermentation characteristics. To achieve this objective, an eight-week in vivo trial on Italian Mediterranean Buffalo cows and an in vitro rumen fermentation using buffalo ruminal fluid were performed. Parameters evaluated included diet chemical composition and in vitro fermentation characteristics, milk yield and composition, fecal composition and volatile fatty acids (VFA) and blood biochemical metabolites. In vivo results showed that, buffaloes receiving the yeast-enzyme supplement exhibited improve milk fat (p < 0.001), protein (p < 0.001) and casein (p < 0.05) content and the production of energy corrected milk (p < 0.01). Fecal analyses revealed a lower starch (p < 0.05) content and differences in acetate and total VFA concentrations in the supplemented group. Blood biochemical analyses further showed higher glucose (p < 0.001), lower blood urea nitrogen (p < 0.001) and triglyceride (p < 0.05) at the end of the trial. Conversely, in vitro fermentation results exhibited greater VFA production in the non-treated group (p < 0.001), whereas faster fermentation kinetics in the treated group. These results support the use of microbial and enzymatic feed additives as a promising nutritional strategy for modulating the composition of milk, particular blood biochemical parameters, and rumen fermentation characteristics of lactating buffaloes, thereby supporting the need for further study of these additives as a nutritional strategy in buffalo dairy production.
In this study, Simmental cattle at different physiological stages were evaluated for heat stress based on the THI and physiological parameters, and serum biochemical profiling, 16S rRNA gene sequencing, metagenomic sequencing, and LC–MS/MS-based untargeted metabolomics were integrated to characterize heat stress-associated changes in production performance, immune and oxidative stress indices, reproductive hormones, the vaginal microbiota, and vaginal and serum metabolites, with Spearman correlation analysis used to integrate microbial, metabolic, and serum variables. A mouse model was further used to evaluate the biological effects of a key differentially abundant bacterial taxon. The results showed that heat stress was associated with reduced rumination time, activity, and milk yield, together with alterations in immune and oxidative stress indices and decreased serum levels of LH, FSH, PRL, P4, and GnRH. Vaginal microbiota analysis revealed differences in several α-diversity indices and the abundance of specific bacterial taxa between heat-stressed and non-heat-stressed cattle, whereas separation of the overall microbial community structure was limited. Vaginal and serum metabolomic analyses revealed distinct metabolic profiles between heat-stressed and non-heat-stressed conditions, with elevated serum 5-HT levels observed in heat-stressed cattle. Multi-omics correlation analysis further showed that the abundance of Pseudomonas syringae (P. syringae) was negatively correlated with GnRH, P4, PRL, and LH levels and positively correlated with serum 5-HT levels, revealing an association among vaginal microbial alterations, 5-HT metabolism, and changes in reproductive hormones. Following intraperitoneal inoculation of mice with P. syringae, serum 5-HT and MT levels increased, whereas FSH and GnRH levels decreased, with no significant change in LH levels. Collectively, these findings indicate that heat stress in Simmental cattle is accompanied by coordinated alterations in production performance, reproductive endocrine profiles, the vaginal microbiota, and host metabolism. This study provides a novel perspective for understanding the reproductive endocrine changes associated with heat stress in Simmental cattle.
Porcine reproductive and respiratory syndrome (PRRS) is economically devastating to pork producers worldwide. Our goal is to identify critical tissues and genes that forecast fetal resistance, resilience or susceptibility. We hypothesized that targeted gene expression may elucidate mechanisms involved in resistance and resilience, observed in fetuses which did not exhibit infection or maintained low viral load (VL), respectively. In this study, pregnant gilts (N = 27) were infected with PRRSV at day 85 ± 0.9 of gestation. At 21 days post maternal inoculation, the gilts and fetuses were euthanized, and fetal tissues collected for investigation. A subset of fetuses was selected based on PRRS VL in placenta (PLC), fetal serum (SER), and fetal thymus (THY). We compared six distinct fetal groups: control (CTRL) from mock infected sows; and, from infected sows, uninfected (UNIF; 0.0 log VL in PLC, SER, THY); PLCO (VL only in PLC); PLCSER (VL in PLC, SER); THYL (VL in PLC, SER, low VL THY < 2.0 log VL), and THYM (VL in PLC, SER, medium VL THY > 2.5 log VL). RNA was extracted from fetal heart, liver, and thymus and differential gene expression (DEG) evaluated based on 168 gene targets and 12 groupings, hypothesized to be involved in fetal outcome (PRRS resistance, resilience or susceptibility), using NanoString transcriptomics. Our data revealed that anti-viral responses were only observed when the VL was > 2.5 log VL per μg in the thymus; almost no DEGs were found even with high fetal serum VL (PLCSER). In THYM vs CTRL fetal VL category, the heart had a relatively robust response with 34/168 DEG, liver followed with 12/168 DEG, whereas the thymus exhibited only 2/168 DEG. These results raise uncertainty regarding the primary role of the thymus in the fetus’ early anti-viral response. In contrast, the results indicate early responsiveness to the virus, as evidenced by differential gene expression in non-lymphoid tissues, as critical for fetal survival.
Growth, carcass composition and reproductive performance are economically important traits in chickens. Polymorphisms in the genes encoding growth hormone (GH), its receptor (GHR) and insulin-like growth factor-1 (IGF-1), and prolactin (PRL), which regulates incubation behaviour and egg laying, have been associated with these traits, with inconsistent findings across breeds. This review evaluated the consistency of these associations and their potential use in genetic improvement. Scopus and Web of Science were searched for studies published between January 2013 and August 2026. Studies reporting associations between polymorphisms in the four genes and growth, carcass or reproductive traits in chickens were included. Data were extracted in a standardised form, reporting completeness was assessed against eight core data elements, and associations were synthesised by vote-counting, distinguishing replication within a study from replication across independent studies. Study characteristics were examined with a co-occurrence network analysis using the Louvain community-detection algorithm. Thirty-eight English-language studies were included, most from Asia, Africa and the Middle East, and more than half examined indigenous breeds. Polymerase chain reaction–restriction fragment length polymorphism genotyping was used in 22 studies. The co-occurrence analysis grouped the literature into a growth-oriented community (GH, GHR and IGF-1) and a reproduction-oriented community (PRL). Reporting completeness of the core data required for synthesis was high, although Hardy–Weinberg equilibrium testing, covariate adjustment and effect sizes were reported less consistently. The PRL promoter 24-bp insertion/deletion and the g.2402 C > T polymorphism were most often significant for reproductive traits, and IGF-1 variants in the 5′ untranslated region were associated with growth in three of the four studies that tested them, and promoter variants less consistently. Only two locus–trait combinations were significant in more than one independent study. Evidence for GH was spread across many loci and traits, and evidence for GHR was limited. Several PRL and IGF-1 regulatory variants were the most frequently significant candidates and warrant further study, but few studies reported the effect sizes, baseline performance or independent validation needed to support marker-assisted selection. Once validated, these variants may be most useful as prior biological information in genomic selection models, particularly for indigenous breeds.
