Comparative expression profile of NOD1/2 and certain acute inflammatory cytokines in thermal-stressed cell culture model of native and crossbred cattle.

Thermotolerance depends mainly on the health and immune status of the animals. The variation in the immune status of the animals may alter the level of tolerance of animals exposed to heat or cold stress. The present study was conducted to investigate the expression profile of two important nucleotide binding and oligomerization domain receptors (NLRs) (NOD1 and NOD2) and their central signalling molecule RIP2 gene during in vitro thermal-stressed bovine peripheral blood mononuclear cells (PBMCs) of native (Sahiwal) and crossbred (Sahiwal X HF) cattle. We also examined the differential expression profile of certain acute inflammatory cytokines in in vitro thermal-stressed PBMC culture among native and its crossbred counterparts. Results revealed that the expression profile of NOD1/2 positively correlates with the thermal stress, signalling molecule and cytokines. Present findings also highlighted that the expression patterns during thermal stress were comparatively superior among indigenous compared to crossbred cattle which may add references regarding the better immune adaptability of Zebu cattle.

Differential effect of thermal stress on HSP70 expression, nitric oxide production and cell proliferation among native and crossbred dairy cattle.

In a tropical country like India, thermal stress is one of the major factors which significantly affects the productivity of dairy cattle. The present study was aimed to identify the effect of heat and cold stress on cell viability, mitogen stimulation indices, nitric oxide production and HSP70 expression in Sahiwal and Holstein crossbred (Frieswal) population in India. The results indicated that the Sahiwal breed can better withstand the effect of heat and cold stress significantly (P<0.05) when compared to the crossbred cattle due to the higher survivability of the Peripheral Blood Mononuclear Cells (PBMCs) and Phytohemagglutinin (PHA-P) mitogen based stimulation indices. The study also revealed the significant differences (P<0.05) in the level of nitric oxide (µM) production amongst the pre and post thermal stressed samples of Sahiwal and Frieswal crossbred samples. Further, the expression of HSP70 was significantly (P<0.05) higher in Sahiwal compared to Frieswal immediately after heat/cold shock to 6h of recovery as indirect ELISA analysis showed gradual rise in the Hsp70 protein concentration (ng/ml) immediately after heat and cold stress (0h) and reached the peak at 6h of recovery. Western blot and immune fluorescent assay results were also corroborated with the findings of indirect ELISA. In Sahiwal cattle the mRNA expression of HSP70 and its protein concentration were higher (P<0.05) during peak summer (44°C) and winter (10°C) as compared to Frieswal cattle. This investigation supports the earlier information on the higher adaptability of indigenous cattle breeds to hot and humid conditions compared to the crossbreds of temperate cattle breeds.