Impact of heat stress, nutritional stress and combined (heat and nutritional) stresses on rumen associated fermentation characteristics, histopathology and HSP70 gene expression in goats

Abstract

A study was conducted to assess the impact of heat stress, nutritional stress and combined stresses (heat and nutritional stress) on rumen fermentation characteristics, histopathology of rumen and rumen HSP70 gene expression in goats. Twenty four adult Osmanabadi bucks were divided into four groups, C (n=6; control), HS (n=6; heat stress), NS (n=6; nutritional stress) and CS (n=6; combined stress). The study was conducted for a period of 45 days. The C and HS bucks had ad libitum access to their feed while NS and CS bucks were subjected to restricted feed (30% intake of C bucks) to induce nutritional stress. The HS and CS bucks were exposed to heat stress in an outside environment. Both feed intake and body weight were significantly (p < 0.01) lower in CS and NS groups. The carboxy methyl cellulase activities-extracellular, intracellular and total activity in the rumen fluid differed significantly (p < 0.01) between the groups. The highest concentration of ammonia nitrogen (p < 0.05) was recorded in C while the lowest in the CS group. The concentration of total nitrogen and trichloroacetic acid precipitable N, propionic acid, butyric acid, and valeric acid was lower (p < 0.01) in the restricted fed (NS and CS) bucks as compared to ad libitum fed groups (C and HS). Further, the ratio of acetate to propionate (A:P ratio) was also significantly (p < 0.01) higher in CS and NS groups. The higher expression of rumen heat shock protein 70 (HSP70) mRNA was observed in CS goats. The histopathological section of rumen revealed a reduction in the length of rumen villi and thickness in CS, whereas rumen keratinization was highest in the CS group. From the study it can be concluded that when two stresses occur simultaneously, they may have severe impact on rumen fermentation characteristics of bucks.

The Low Dose of Saccharomyces cerevisiae Is Beneficial for Rumen Fermentation (Both In Vivo and In Vitro) and the Growth Performance of Heat-Stressed Goats

“…The occurrence of heat stress in goats was judged accurately is the guarantee of the follow-up experiment of this study. Previous studies have reported several methods to assess the occurrence of heat stress in goats: monitoring the environmental temperature and relative humidity, measuring the physiological parameters (skin temperature, rectal temperature, pulse, and respiratory rate), determining the expression levels of HSP 70 genes in blood and rumen fluid, and measurement the cortisol concentrations in serum [ 3 , 4 , 25 ]. However, only one indicator of these indicators is used to determine whether heat stress has occurred in a single study.…”

“…A Revert Aid First Strand cDNA Synthesis kit (K1621, Thermo Fisher Scientific, Waltham, MA, USA) was then used for reverse transcription. Primers were referred to as Chaidanya et al [ 4 ] and Cai et al [ 25 ] and were synthesized by Sangon Biotech Co., Ltd. (Shanghai, China). The details of the gene-specific primer sequences are given in Table 2 .…”

“…Therefore, goats in this region are easily exposed to heat stress during the summer [ 3 ]. Heat stress could lead to several adverse influences on rumen fermentation, including decreased ruminal pH values, the concentration of ruminal volatile fatty acids (VFAs), the activities of digestive enzymes, and the feed digestibilities [ 3 , 4 , 5 ]. These adverse influences eventually cause a significant decline in growth performance, and then lead to economic loss [ 6 ].…”

Prophylactic Feeding of Clostridium butyricum and Saccharomyces cerevisiae Were Advantageous in Resisting the Adverse Effects of Heat Stress on Rumen Fermentation and Growth Performance in Goats

“…The peripheral blood lymphocytes were isolated from whole blood using a specific kit from Solarbio Science & Technology (Beijing, China) to determine the expression levels of heat shock protein 70 (HSP 70) genes. The primer sequences, as described by Cai et al [ 10 ] and Chaidanya et al [ 19 ], were synthesized by Sangon Biotech Co., Ltd. (Shanghai, China). The details of these primers are given in Table 2 .…”

Quantitative analysis of expression patterns of different cell surface Toll-like receptor genes imparting heat stress resilience to indigenous Osmanabadi and Salem Black goat breeds

“…Heat waves are extreme meteorological event in the changing climate scenario causing extreme heat stress which affects severely the welfare of the animals (Bernabucci and Mele 2014;Rashamol et al 2018). Particularly, heat stress has a negative influence on farm animal productivity and health because of the presence of close relationship between metabolic heat generation and production level (Bernabucci et al 2010;Chaidanya et al 2017).…”