Buffalo is an important livestock species. Here, we present a comprehensive metagenomic survey of the microbial communities along the buffalo digestive tract. We analysed 695 samples covering eight different sites in three compartments (four-chambered stomach, intestine, and rectum). We mapped ~85% of the raw sequence reads to 4,960 strain-level metagenome-assembled genomes (MAGs) and 3,255 species-level MAGs, 90% of which appear to correspond to new species. In addition, we annotated over 5.8 million nonredundant proteins from the MAGs. In comparison with the rumen microbiome of cattle, the buffalo microbiota seems to present greater potential for fibre degradation and less potential for methane production. Our catalogue of microbial genomes and the encoded proteins provides insights into microbial functions and interactions at distinct sites along the buffalo digestive tract.

Bovine and buffalo are important livestock species that have contributed to human lives for more than 1000 years. Improving fertility is very important to reduce the cost of production. In the current review, we classified reproductive traits into three categories: ovulation, breeding, and calving related traits. We systematically summarized the heritability estimates, molecular markers, and genomic selection (GS) for reproductive traits of bovine and buffalo. This review aimed to compile the heritability and genome-wide association studies (GWASs) related to reproductive traits in both bovine and buffalos and tried to highlight the possible disciplines which should benefit buffalo breeding. The estimates of heritability of reproductive traits ranged were from 0 to 0.57 and there were wide differences between the populations. For some specific traits, such as age of puberty (AOP) and calving difficulty (CD), the majority beef population presents relatively higher heritability than dairy cattle. Compared to bovine, genetic studies for buffalo reproductive traits are limited for age at first calving and calving interval traits. Several quantitative trait loci (QTLs), candidate genes, and SNPs associated with bovine reproductive traits were screened and identified by candidate gene methods and/or GWASs. The IGF1 and LEP pathways in addition to non-coding RNAs are highlighted due to their crucial relevance with reproductive traits. The distribution of QTLs related to various traits showed a great differences. Few GWAS have been performed so far on buffalo age at first calving, calving interval, and days open traits. In addition, we summarized the GS studies on bovine and buffalo reproductive traits and compared the accuracy between different reports. Taken together, GWAS and candidate gene approaches can help to understand the molecular genetic mechanisms of complex traits. Recently, GS has been used extensively and can be performed on multiple traits to improve the accuracy of prediction even for traits with low heritability, and can be combined with multi-omics for further analysis.

Fibroblast growth factor 2 (FGF2), a member of FGF family, binds with FGF receptors (FGFR) to initiate biological functions in various somatic cells. However, little is known regarding the role of FGF2/FGFR on oocyte meiosis. In this study, we investigated expression patterns and functions of FGF2/FGFR during in vitro maturation (IVM) of mouse cumulus-oocyte complexes (COCs). Among four FGFRs, Ffgr1 was the most abundant in COCs. The transcripts for Fgf2 and Ffgr1 in COCs increased during IVM. Ffgr1 was present in oocytes and cumulus cells, while Fgf2 was present in only cumulus cells. Treatment of COCs with the selective FGFR inhibitor SU5402 blocked oocyte meiotic progression and downregulated expression of Bmp15 and Gdf9. In contrast, supplement of FGF2 promoted oocyte meiotic progression and upregulated Bmp15 and Gdf9 expression. Inhibition of FGFR with SU5402 reduced cumulus expansion and expressions of Ptx3, Has2 and Tnfaip6. Treatment with FGF2 increased Ptx3 and Has2 expression. Inhibition of FGFR had no effect on meiotic progression of denuded oocytes (DOs). However, co-culture of DOs with COCs or supplementation with FGF2 promoted meiotic progression of DOs. Inhibition of FGF2/FGFR signaling also downregulated Ffgr1 expression, while supplemental FGF2 upregulated Fgfr1 expression. Furthermore, inhibition of FGFR in COCs interrupted the c-Mos/MAPK pathway and maturation-promoting factor (MPF), as indicated by downregulation of oocyte c-mos and Ccnb1 transcripts, respectively. Overall, this study suggests that FGF2 produced by cumulus cells, activates a FGF2/FGFR autocrine/paracrine loop within COCs to regulate cumulus expansion and oocyte meiosis. These findings reveal a novel role for FGF2/FGFR signaling during in vitro maturation of COCs.

Babesiosis is a tick-borne disease with global impact caused by parasites of the phylum Apicomplexa, genus Babesia. Typically, acute bovine babesiosis (BB) is characterized by fever, anemia, hemoglobinuria, and high mortality. Surviving animals remain persistently infected and become reservoirs for parasite transmission. Bovids in China can be infected by one or more Babesia species endemic to the country, including B. bovis, B. bigemina, B. orientalis, B. ovata, B. major, B. motasi, B. U sp. Kashi and B. venatorum. The latter may pose a zoonotic risk. Occurrence of this wide diversity of Babesia species in China may be due to a combination of favorable ecological factors, such as the presence of multiple tick vectors, including Rhipicephalus and Hyalomma, the coexistence of susceptible bovid species, such as domestic cattle, yaks, and water buffalo, and the lack of efficient measures of tick control. BB is currently widespread in several regions of the country and a limiting factor for cattle production. While some areas appear to have enzootic stability, others have considerable cattle mortality. Research is needed to devise solutions to the challenges posed by uncontrolled BB. Critical research gaps include risk assessment for cattle residing in endemic areas, understanding factors involved in endemic stability, evaluation of parasite diversity and pathogenicity of regional Babesia species, and estimation of whether and how BB should be controlled in China. Research should allow the design of comprehensive interventions to improve cattle production, diminish the risk of human infections, and increase the availability of affordable animal protein for human consumption in China and worldwide. In this review, we describe the current state of BB with reference to the diversity of hosts, vectors, and parasite species in China. We also discuss the unique risks and knowledge gaps that should be taken into consideration for future Babesia research and control strategies.

Female subfertility is an increasing reproductive issue worldwide, which is partially related to abnormal ovarian follicular development. Granulosa cells (GCs), by providing the necessary physical support and microenvironment for follicular development, play critical roles in maintaining female fertility. We previously showed that ectopic expression of four and a half LIM domains 2 (FHL2) promoted ovarian granulosa cell tumor progression. However, its function in follicular development and fertility remains unknown. Here, we confirmed that FHL2 is highly expressed in human and mouse ovaries. FHL2 immunosignals were predominantly expressed in ovarian GCs. A Fhl2 knockout (KO) mouse model was generated to examine its roles in follicular development and fertility. Compared with wildtype, knockout of Fhl2 significantly decreased female litter size and offspring number. Furthermore, Fhl2 deficiency reduced ovarian size and impaired follicular development. RNA-sequencing analysis of GCs isolated from either KO or WT mice revealed that, Fhl2 deletion impaired multiple biological functions and signaling pathways, such as Ovarian Putative Early Atresia Granulosa Cell, ErbB, Hippo/YAP, etc. In vitro studies confirmed that FHL2 silencing suppressed GCs growth and EGF-induced GCs proliferation, while its overexpression promoted GC proliferation and decreased apoptosis. Mechanistic studies indicated that FHL2, via forming complexes with transcriptional factors AP-1 or NF-κB, regulated Egf and Egfr expression, respectively. Besides, FHL2 depletion decreased YAP1 expression, especially the active form of YAP1 (nuclear YAP1) in GCs of growing follicles. EGF, serving as an autocrine/paracrine factor, not only induced FHL2 expression and nuclear accumulation, but also stimulated YAP1 expression and activation. Collectively, our study suggests that FHL2 interacts with EGFR and Hippo/YAP signaling to regulate follicular development and maintain fertility. This study illuminates a novel mechanism for follicular development and a potential therapeutic target to address subfertility.