Muhammad Rizwan

The early larval stage is a major bottleneck in freshwater aquaculture because conventional live feeds are not always available for optimum nutrient availability and digestibility to satisfy the nutritional requirements of developing larvae. This study evaluated the effects of micro- and nano-particulate fermented and fish protein hydrolysate-based diets on growth, digestive enzyme activity, intestinal morphology, and immune-related gene expression in common carp (Cyprinus carpio) larvae. Four experimental diets, namely fish hydrolysate-based micro-feed (FHMF), fermented micro-feed (FMF), fish hydrolysate-based nano-feed (FHNF), and fermented nano-feed (FNF), were compared with a basal diet. Feed characterization confirmed the successful production of micro- (5–15 µm) and nano-sized (90–105 nm) particles with distinct physicochemical properties. Three-day-old hatchlings were reared for 45 days, and growth performance, survival, digestive enzyme activities, intestinal histomorphology, and gene expression were analyzed. Diet type significantly influenced all measured parameters (p < 0.001). Among the treatments, FNF consistently produced the highest growth, survival, digestive enzyme activities, villus development, and muscular layer thickness. Growth-related genes (GH, IGF-1, and ghrelin) and immune-related genes (lysozyme, TNF, IL-1β, IL-10, and TGF-β) also followed an upregulated trend. These findings demonstrate that nanoparticulate fermented feed is a promising nutritional strategy for enhancing larval growth, digestion, immune competence, and production efficiency in common carp aquaculture.

Kluyveromyces marxianus is a rapidly growing thermotolerant yeast that secretes a variety of lytic enzymes, utilizes different sugars, and produces ethanol. The probiotic potential of this yeast has not been well explored. To evaluate its probiotic potential, the yeast strain Kluyveromyces marxianus DMKU3-1042 was analyzed using next-generation sequencing technology. Analysis of the genomes showed that the yeast isolates had a GC content of 40.10–40.59%. The isolates had many genes related to glycerol and mannose metabolism, as well as genes for acetoin and butanediol metabolism, acetolactate synthase subunits, and lactic acid fermentation. The strain isolates were also found to possess genes for the synthesis of different vitamins and Coenzyme A. Genes related to heat and hyperosmotic shock tolerance, as well as protection against reactive oxygen species were also found. Additionally, the isolates contained genes for the synthesis of lysine, threonine, methionine, and cysteine, as well as genes with anticoagulation and anti-inflammatory properties. Based on our analysis, we concluded that the strain DMKU3-1042 possesses probiotic properties that make it suitable for use in food and feed supplementation.

The mRNAs and long non-coding RNAs axes are playing a vital role in the regulating of post-transcriptional gene expression. Thereby, elucidating the expression pattern of mRNAs and long non-coding RNAs underlying testis development is crucial. In this study, mRNA and long non-coding RNAs expression profiles were investigated in 3-month-old calves and 3-year-old mature bulls’ testes by total RNA sequencing. Additionally, during the gene level analysis, 21,250 mRNAs and 20,533 long non-coding RNAs were identified. As a result, 7908 long non-coding RNAs (p-adjust < 0.05) and 5122 mRNAs (p-adjust < 0.05) were significantly differentially expressed between the distinct age groups. In addition, gene ontology and biological pathway analyses revealed that the predicted target genes are enriched in the lysine degradation, cell cycle, propanoate metabolism, adherens junction and cell adhesion molecules pathways. Correspondingly, the RT-qPCR validation results showed a strong consistency with the sequencing data. The source genes for the mRNAs (CCDC83, DMRTC2, HSPA2, IQCG, PACRG, SPO11, EHHADH, SPP1, NSD2 and ACTN4) and the long non-coding RNAs (COX7A2, COX6B2, TRIM37, PRM2, INHBA, ERBB4, SDHA, ATP6VOA2, FGF9 and TCF21) were found to be actively associated with bull sexual maturity and spermatogenesis. This study provided a comprehensive catalog of long non-coding RNAs in the bovine testes and also offered useful resources for understanding the differences in sexual development caused by the changes in the mRNA and long non-coding RNA interaction expressions between the immature and mature stages.