Differential expression of immune response genes associated with subclinical mastitis in dairy buffaloes

Abstract

Buffalo milk production has become of significant importance on the world scale, however, there are few studies involving biotechnological tools specifically for buffalo. To verify the effects caused by subclinical mastitis on the components of milk and to study the innate immune system in the udder of dairy buffaloes with subclinical mastitis, we evaluated the levels of expression of the lactoferrin (LTF), tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin-8 (IL-8), and toll-like receptors 2 (TLR-2) and 4 (TLR-4) genes in buffaloes with and without subclinical mastitis. Milk samples were collected for the determination of milk components: somatic cell score (SCS), fat, protein, lactose, total solids and solids-not-fat (SNF), as well as for RNA extraction of milk cells, complementary DNA synthesis, and expression profile quantification by quantitative real-time PCR. For gene expression, the ΔΔCt was estimated using contrasts of the target genes expression adjusted for the expression of the housekeeping genes between both groups. Linear regression analysis was performed to determine the relationship between the genes studied and the milk components. Subclinical mastitis induced changes in the fat, lactose and SNF in milk of buffaloes, and the messenger RNA abundance was upregulated for TLR-2, TLR-4, TNF-α, IL-1β and IL-8 genes in milk cells of buffaloes with subclinical mastitis, whereas the LTF gene was not differentially expressed. Results of linear regression analysis showed that TLR-2 gene expression most explains the variation in SCS, and the change in a unit of ΔCt of the TNF-α gene would result in a higher increase in SCS. The study of these immune function genes that are active in the mammary gland is important to characterize the action mechanism of the innate immunity that occurs in subclinical mastitis in dairy buffaloes and may aid the development of strategies to preserve the health of the udder.

Genomic studies of milk-related traits in water buffalo (Bubalus bubalis) based on single-step genomic best linear unbiased prediction and random regression models

“…In this context, SCC can be used as an indicator of mastitis resistance (Martin et al, 2018). Furthermore, elevated SCC may have a negative effect on milk yield and composition, reducing the cow's productive life and leading to significant economic losses for the industry (Alhussien and Dang, 2018;Tanamati et al, 2019). The SCC also has direct economic value for buffalo producers as there is a financial penalty for high SCC in the milk sold to processors (Sadeghi-Sefidmazgi et al, 2011;Kheirabadi and Razmkabir, 2016;Murphy et al, 2016).…”

“…Genomic RRM also provide an opportunity to determine the genomic regions and candidate genes associated with traits of interest at specific time points (Oliveira et al, 2019b;Freitas et al, 2020a) that might have influenced specific lactation stages for milk traits in buffalo (Barros et al, 2018;Tanamati et al, 2019;Gonzalez Guzman et al, 2020). The use of statistical models that consider all the variability from repeated records can increase the statistical power for detecting time-dependent QTL and, consequently, candidate genes affecting traits in specific lactation stages (Szyda et al, 2014;Strucken et al, 2015;Ning et al, 2017;Oliveira et al, 2019b).…”

Genetic Association of Polymorphism and Relative mRNA Expression of Tumor Necrosis Factor-Alpha Gene in Mastitis in Sahiwal Cow

“…The findings revealed that the immune response of mastitis affected groups (clinical and subclinical) consisting a higher TNF-a mRNA expression along with up-regulation of serves as a crucial defense mechanism, which is lacking in non-mastitic Sahiwal cows (Ranjan et al 2015). The mRNA expression of TLR-2 TNF-a, 7.15,62.49 and 26 times higher in subclinically mastitic buffaloes, as were also observed in cattle (Fonseca et al 2015;Tanamati et al 2019). Our findings seem to support the research of other authors which suggests that immune system genes are important to characterize the action mechanism of the immune system that occurs in clinical and subclinical mastitis.…”

Expressions of IL4, IL10, and IFN"&#".ord($0).";""&#".ord($0).";" cytokines genes during bacterial mastitis

“…Pathogens can be quantified in infected milk using quantitative RT-PCR; milk cells can be used to extract RNA; complementary DNA can be synthesized; and the expression profile can be quantified using quantitative real-time PCR. For gene expression, the Ct was calculated by comparing the target gene’s expression to the housekeeping gene’s expression [ 26 ]. In a turn of events, the PCR procedure has been generally utilized in many areas of scientific research.…”