Brahman cattle are tolerant to parasite challenges and heat stress. Yunling cattle are three-way hybrids that are half Brahman cattle, a fourth Murray Grey cattle and a fourth Yunnan Yellow cattle, with good beef performance. The hematological and biochemical parameters can reflect the physiology and metabolic conditions of cattle, and there are valuable indicators of production performance and adaptability that can be found by studying the cattle. To assess the health status and differences, we compared 55 hematological and biochemical parameters of 28 Brahman cattle and 65 Yunling cattle using an automatic biochemical analyzer. Our results showed that 27 hematological and biochemical indices of Brahman cattle were lower than those of Yunling cattle, whereas the other parameters were higher. There are 20 indices with significant differences that were detected between Brahman and Yunling cattle (with p ≤ 0.01 or 0.01 ≤ p ≤ 0.05, respectively), and no significant differences were found for other indices (p > 0.05). Based on these results, Yunling cattle may have a better physical condition than Brahman cattle, may be better at adapting to local environments, and can maintain a good production and reproduction performance. As a new breed that is half Brahman, the abilities of Yunling cattle, including adaptability, stress resistance and tolerance to crude feed, were better than Brahman cattle under the same management conditions.

Yunling cattle, a native breed native to subtropical regions, exhibit remarkable traits such as heat tolerance, strong immunity, and tick resistance. To characterize the genetic architecture of blood physiological and biochemical traits associated with these adaptations, we performed a genome-wide association study (GWAS) using whole-genome resequencing data from 97 individuals combined alongside 39 blood traits (30 analysed after quality control). Significant association signals were detected for seven traits: albumin (ALB), homocysteine (CYS), white blood cell count (WBC), bilirubin (BIL), indirect bilirubin (I-BIL), low-density lipoprotein cholesterol (LD-CHO), and red cell distribution width (RDW). Notably, loci related to leukocyte parameters overlapped with strong selection signals and were mapped to classical bovine leukocyte antigen (BOLA) genes, including BOLA, BOLA-DQB and BOLA-DQA5, which are located within the MHC region and are known to be involved in immune regulation. For lipid-related traits, the strongest signals were identified near RPL22L1 and SLC7A14 on chromosome 1, while additional associated genes included XPOT, SLC16A7, SCAI, SYT14 and ATP2B2. Additionally, regarding metabolic and protein parameters, NHSL1 showed a strong association with bilirubin; this gene has previously been reported to be associated with hypertension. Red blood cell parameters revealed candidate genes such as NAV3, LSAMP, ACACA, and others linked to erythrocyte variation. For Homocysteine-related traits, CIITA was significantly associated with Homocysteine levels; CIITA is known to be involved in immune regulation. In conclusion, this study provides a genome-wide characterization of the genetic architecture of blood traits in Yunling cattle, identifying several candidate genes (e.g., MOB1B, CIITA and BOLA genes) associated with blood physiological and biochemical traits. These candidate loci provide a foundation for further functional validation; validation in larger and independent populations is needed before any application.

The mudflat crab (H. tientsinensis) is a dominant species in coastal tidal flat areas, primarily inhabiting the high tide region of the intertidal zone, and possesses significant ecological and economic value. Vibrio species are one of the main bacterial pathogens responsible for diseases in marine organisms, and they are widely distributed in seawater and estuarine environments. However, the immune mechanisms employed by H. tientsinensis in response to Vibrio infections remain unclear. This study aims to investigate the physiological and immune mechanisms by analyzing the structural changes and differential gene expression in the gill and hepatopancreas following Vibrio parahaemolyticus infection. The results indicate that V. parahaemolyticus infection causes cellular damage, with structural alterations observed in the gills (epithelial cell edema in the gill filaments, and aneurysm formation) and the hepatopancreas (changes in lumen size, nuclear condensation, and modifications in connective tissue morphology). Transcriptome analysis revealed 9766 differentially expressed genes (DEGs) in the gills of the experimental group, with 4687 upregulated and 5079 downregulated genes. These DEGs are primarily involved in different ribosomal subunits. In the hepatopancreas, 1594 DEGs were identified, with 834 upregulated and 760 downregulated. These DEGs are predominantly associated with energy-coupled proton transmembrane transport, electron transport-coupled proton transport, and lipid transporter activity. H. tientsinensis gene annotation and KEGG enrichment analysis revealed that chemical carcinogens DNA adducts, amino acid metabolism, and some immune pathways play key roles in the ability of H. tientsinensis to defend against V. parahaemolyticus infection. The findings of this study contribute to a deeper understanding of the immune mechanisms of H. tientsinensis against V. parahaemolyticus infection and provide new insights for aquaculture management.