Investigating the heat tolerance and production performance in local chicken breed having normal and dwarf size

Heat stress significantly impairs the growth performance of broilers, which causes serious losses to the poultry industry every year. Thus, understanding the performance of indigenous chicken breeds under such environment is crucial to address heat stress problem. The purpose of this study was to investigate the effects of heat stress (HS) on production performance, tissue histology, heat shock response (HSP70, HSP90), and muscle growth-related genes (GHR, IGF-1, and IGF-1R) of Normal yellow chicken (NYC) and Dwarf yellow chicken (DYC). Seventy-two female birds from each strain were raised under normal environmental conditions up to 84 days, with birds from each strain being divided into two groups (HS and control). In the HS group, birds were subjected to high temperature at 35 ± 1 °C for 8 h daily and lasted for a week, while in the control group, birds were raised at 28 ± 1 °C. At 91 days old, bird's liver, hypothalamus, and breast muscle tissues were collected to evaluate the gene expression, histological changes, and the production performance. The Feed intake, weight gain ratio, total protein intake and protein efficiency ratio showed a significant reduction in the treatments (P < 0.01) and treatment × strain interaction (P < 0.05) with breast muscle rate significantly reducing among the treatments (P < 0.01) after 7 days of HS. Correspondingly, total abdominal fat showed significant change among treatment and strain (P < 0.01, P < 0.05), respectively. Besides, HS markedly upregulated the mRNA expression of HSP70 and HSP90 in the pectoralis major of both chicken strains, but no significant increase (P < 0.05) was found in mRNA expression of HSP90 in liver and hypothalamus tissues of both chicken strains. Moreover, HS significantly upregulated (P < 0.05) the expression of lipogenic genes (FASN, ACC) in liver tissues of NYC, while mRNA expression of these genes showed no variation in DYC. Similarly, HS downregulated the mRNA expression of muscle growth-related genes (GHR, IGF-1, and IGF-1R). Consequently, the histopathological analysis showed that histological changes were accompanied by inflammatory cell infiltration in liver tissues of both chicken strains; however, histopathological changes were more severe in NYC than dwarf chicken strain. Conclusively, this study depicted that the production performance and growth rate varied significantly between treatment and control group of NYC. However, heat treatment in DYC has not shown significant damaging consequences as compared to the control group that signifies the vital role of the dwarf trait in thermal tolerance.     

The effect of hyperthermia on cell viability,oxidative damage,and heat shock protein expression in hepatic cells of grass carp (Ctenopharyngodon idellus)

The purpose of the study was to investigate the effects of mild hyperthermia on cell viability, release of lactate dehydrogenase (LDH), superoxide dismutase (SOD) activity, malondialdehyde (MDA) formation, total antioxidant capacity (T-AOC), and the relative mRNA levels of heat shock protein (HSP60, 70, and 90) in hepatic cells of grass carp (Ctenopharyngodon idellus) before and after temperature stress. Cultured cells were exposed to thermal stress (32 °C) for 0.5, 1, 2, 4, and 8 h. The results showed that hyperthermia stress significantly reduced cell viability (P<0.01) and increased LDH release at 0.5 and 1 h (P<0.05). Additionally, hyperthermia stress led to oxidative stress as evidenced by significantly decreased T-AOC after treating cells for 0.5 and 8 h (P<0.05). SOD activity also significantly decreased after 1 h of stress (P<0.05), but MDA formation increased after 8 h of stress (P<0.05). This may be partly responsible for the lower cell viability and higher LDH release we observed. The differences between SOD activity, MDA formation, and T-AOC between the 2 h treatment group and the control were smaller than that of other groups. This indicated that cellular antioxidant enzyme systems play an important role in the defense against oxidative stress. Further tests showed that the expression of HSP60 at 1, 2, and 4 h (P<0.05), HSP70 at 0.5 and 1 h (P<0.01), and HSP90 at all time points after stress were higher (P<0.01) than pre-stress levels. This suggested that HSPs possess the ability to modulate cellular anti-stress responses and play key roles in protecting organisms from heat stress. In conclusion, hyperthermia inhibits cell proliferation, induces cell oxidative stress, and enhances HSP expression in hepatic cells of grass carp.     

Evaluation of physiological and molecular responses to acute heat stress in two chicken breeds

High environmental temperatures are a foremost concern affecting poultry production; thus, understanding and controlling such conditions are vital to successful production and welfare of poultry. In view of this, a completely randomized design with a 2 × 2 factorial arrangement involving two local strains (Kirin chicken (KC) and Three-yellow chicken (TYC)) and two temperature groups (normal/control = 30 ± 2 °C and acute heat stress (AHS) = 35 ± 1 °C for 8-h with 70% humidity) was used to assess the main regulatory factors such as heat shock protein (HSP70) gene, cytokine genes (IL-1β, IL-6, IL-10), muscle development gene (IGF-1) and tissue histopathological changes. At 56 days old, the temperatures of the comb (CT), feet (FT), eyelid (ET) and rectal (RT) from each group were taken thrice at 0, 2, 4 and 8-h during AHS, and 1 and 3-h recovery period after AHS. At 80 days old, the slaughter weight was also analyzed. The CT and ET of the AHS groups increased during the 8-h trial, while the RT of both strains decreased significantly at 4 h but increased at 8 h in the TYC group. All temperature recordings dropped in the AHS groups of both strains during the recovery period. The results revealed that the mRNA expression of HSP70 in the liver was higher in the heat-stressed group of both strains compared to the control. The expression of HSP70 was shown in the AHS-KC group to be significantly high compared to the control (P < 0.05). Moreover, the IGF1 gene in the liver, breast muscle and leg muscle was downregulated in the AHS-TYC group compared to the control (P < 0.05), although that in the AHS-KC was downregulated in the breast muscle. The mRNA expression of spleen IL-1β significantly decreased in the AHS-TYC group (P < 0.01), whereas that of the AHS-KC had no significant difference (P > 0.05). The mRNA expression of spleen IL-6 and IL-10 was increased in the AHS-KC group but did not exhibit obvious changes in the AHS-TYC. Correspondingly, the histopathological examinations revealed tissue injury in the AHS groups of both strains, with the TYC strain experiencing more severe changes. The final live and carcass weights showed a significant enhancement in the treatments (P < 0.01 and P < 0.05, respectively) and treatment × strain interaction (P < 0.05) with breast muscle rate significantly reducing among the treatments (P < 0.01) at 80 days. In conclusion, the differential response to AHS after physiological, molecular and immune response portrays KC to have better thermal tolerance than the TYC.     

Effect of in vitro zinc supplementation on HSPs expression and Interleukin 10 production in heat treated peripheral blood mononuclear cells of transition Sahiwal and Karan Fries cows

The changing climatic scenario with apprehended rise in global temperature is likely to affect the livestock adversely vis-à-vis production and reproduction. This has prompted more focus in addressing the unfavorable effects of thermal stress in livestock system. Presuming that the trace element zinc is indispensible for cellular antioxidant system and immune function, the present study was designed to investigate the effect of zinc treatment on heat stress alleviation and immune modulation in peripheral blood mononuclear cells (PBMC) of indigenous and crossbred transition cows. Twelve cows, six each of Sahiwal and Karan Fries (KF) in their second parity with confirmed pregnancy were selected for the experiment. The blood samples were collected at −21, 0 and +21 days in relation to expected date of calving. The experiment was carried out in vitro after isolating PBMC from whole blood. The 48 h cultured PBMC were subjected to assorted levels of exposures viz. 37 °C, 42 °C to impose heat stress and 42 °C+zinc to alleviate heat stress and modulate immunity. The PBMC viability was 86%, 69% and 78%, respectively. The mRNA expression of heat shock proteins (HSP 40, 70 and 90α) and Interleukin-10 (IL-10) production varied between the two breeds vis-à-vis days and levels of exposure. The mRNA expression of HSP40 and HSP70 was significantly (P<0.05) higher in Karan Fries than the Sahiwal cows. Both the breeds showed maximum expression of HSP on the day of parturition, more so in KF than Sahiwal. There was a significant (P<0.05) difference in the HSP mRNA expression at different levels of exposure. Zinc treatment to heat stressed PBMC caused a significant (P<0.05) down regulation of HSP. For immune status, anti-inflammatory cytokine, IL-10 in the culture supernatant was accessed. The IL-10 was significantly (P<0.05) higher in Karan Fries (168.18±14.09 pg/ml) than the Sahiwal cows (147.24±11.82 pg/ml). The IL-10 concentration was highest on the day of calving. Zinc treatment reduced the IL-10 concentration. From the study, it could be concluded that the zinc supplementation in heat stressed PBMC can ameliorate thermal stress and modulate immune response which can act as a model for reducing heat stress during the periparturient period in tropical livestock.     

The expression of DAMP proteins HSP70 and cancer-testis antigen SPAG9 in peripheral blood of patients with HCC and lung cancer

There are different views of how the immune system participates in the reaction to cancer. Here, we evaluated expression of DAMP proteins HSP70 and cancer-testis antigen SPAG9 in patients with hepatocellular carcinoma (HCC) and lung cancer to explore tumor immunity. Our analysis showed that levels of HSP70 and SPAG9 antibody were significantly higher in the serum of lung cancer and HCC patients than in the serum of healthy subjects (P < 0.001), but there were no differences in levels of HSP70 antibody in patients and controls. Levels of serum SPAG9 antibody in newly diagnosed lung cancer patients were significantly higher than in treated lung cancer patients (P < 0.05), but there were no differences in levels of HSP70 or HSP70 antibody. Levels of serum HSP70 and SPAG9 antibody, but not HSP70 antibody, were also higher in hepatitis/cirrhosis patients than in healthy subjects (P = 0.005, P < 0.001). Levels of serum SPAG9 antibody were significantly higher in HCC patients than in hepatitis/cirrhosis patients, but there were no differences in HSP70 or HSP70 antibody levels. Finally, levels of serum HSP70 and SPAG9 antibody were significantly higher in HCC patients than in lung cancer patients (P < 0.05, P < 0.001). These results indicate that cancer-testis antigen SPAG9 induces a strong humoral immune response in cancer patients but HSP70 does not. These results show that SPAG9 has potential as a tumor-specific biomarker.     

Supplementation of freezing media with alpha lipoic acid preserves the structural and functional characteristics of sperm against cryodamage in infertile men with asthenoteratozoospermia

The aim of this study was to examine the effects of alpha lipoic acid (ALA) supplementation during semen cryopreservation on the sperm quality, chromatin integrity, oxidative stress, and expression level of BAX, BCL2, HSP70 and iNOS genes in semen samples obtained from infertile men with asthenoteratozoospermia.MethodsTwenty freshly ejaculated semen samples were cryopreserved with sperm freezing medium supplemented with 0.00, 0.02, 0.05, 0.1, 0.5, and 1 mmol/mL of ALA. The samples were analyzed according to the WHO guidelines before and after freezing. Sperm ROS production level, DNA fragmentation and cryo-capacitation were assessed using flow cytometry, TUNEL assay and chlortetracycline (CTC) test, respectively. Expression level of stress protein (HSP70), pro-apoptotic Bax, anti-apoptotic Bcl-2, and iNOS genes was assessed by real-time PCR assay.ResultsThe effective concentrations of ALA (0.02 and 0.5 mM) significantly improved the motility, viability and morphology of the frozen-thawed sperms compared to the control group treated with 0.00 mM of ALA. During cryopreservation, treatment of semen with 0.02 mM of ALA, as the optimal concentration, significantly decreased DNA fragmentation and oxidative stress level (P < 0.05), protected the acrosome integrity, and led to insignificant reduction in BAX gene expression level and significant increase in expression level of BCL2, HSP70, and iNOS genes compared with control group.ConclusionOur findings revealed that the adding ALA to semen samples obtained from infertile men with asthenoteratozoospermia plays a significant protective role against cryodamage by preserving the sperm functional parameters.     

Differential expression of lipid metabolism-related genes and myosin heavy chain isoform genes in pig muscle tissue leading to different meat quality

The aim of this study was to investigate the variations in meat quality, lipid metabolism-related genes, myosin heavy chain (MyHC) isoform genes and peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) gene mRNA expressions in longissimus dorsi muscle (LM) of two different pig breeds. Six Rongchang and six Landrace barrows were slaughtered at 161 days of age. Subsequently, meat quality traits and gene expression levels in LM were observed. Results showed that Rongchang pigs not only exhibited greater pH, CIE a*_{24 h} and intramuscular fat content but also exhibited lower body weight, carcass weight, dressing percentage, LM area and CIE b*_{24 h} compared with Landrace pigs (P<0.05). Meanwhile, the mRNA expression levels of the lipogenesis (peroxisome proliferator-activated receptor gamma, acetyl-CoA carboxylase and fatty acid synthase) and fatty acid uptake (lipoprotein lipase)-related genes were greater in the Rongchang (P<0.05), whereas the lipolysis (adipose triglyceride lipase and hormone sensitive lipase) and fatty acid oxidation (carnitine palmitoyltransferase-1B)-related genes were better expressed in the Landrace. Moreover, compared with the Landrace, the mRNA expression levels of MyHCI, MyHCIIa and MyHCIIx were greater, whereas the mRNA expression levels of MyHCIIb were lower in the Rongchang pigs (P<0.05). In addition, the mRNA expression levels of PGC-1α were greater in Rongchang pigs than in the Landrace (P<0.05), which can partly explain the differences in MyHC isoform gene expressions between Rongchang and Landrace pigs. Although the small number of samples does not allow to obtain a definitive conclusion, we can suggest that Rongchang pigs possess better meat quality, and the underlying molecular mechanisms responsible for the better meat quality in fatty pigs may be partly due to the higher mRNA expression levels of lipogenesis and fatty acid uptake-related genes, as well as the oxidative and intermediate muscle fibers, and due to the lower mRNA expression levels of lipolysis and fatty acid oxidation-related genes, as well as the glycolytic muscle fibers.     

Influence of level of inclusion of Azolla leaf meal on growth performance,meat quality and skeletal muscle p70S6 kinase α abundance in broiler chickens

The interest in biodiesel production from oil-bearing seeds rather than soybean necessitates the scientific validation of other good quality protein sources that could substitute soybean meal in animal diets, particularly, broiler chickens where soybean meal constitutes a large portion of their diet. Therefore, the present study was conducted to investigate the effect of sun-dried Azolla leaf meal (ALM) as an unconventional dietary protein source in broiler chicken diet on growth performance, meat quality, skeletal muscle cell growth and protein synthesis through regulation of ribosomal protein S6 kinase (p70S6 kinase α). A total of 120 male Ross 308 broiler chicks were randomly allocated to three dietary treatments. Each treatment had four cages (i.e. replicates) with 10 birds/cage. The control group was fed with a corn–soy-based diet, the AZ5 group was supplemented with 5% ALM and the AZ10 group was supplemented with 10% ALM for 37 days. A 5-day trial was also conducted to measure the apparent nutrient digestibility. Growth performance parameters were measured weekly. At the end of the experiment, 12 birds from each group (3/cage) were euthanized and used for samplings. Inclusion of ALM tended to improve BW gain (P = 0.06) and increased feed intake (P < 0.01). Additionally, ALM decreased the percentage of breast meat cooking loss linearly (P < 0.01). In addition, ALM at a dose of 5% increased the production of propionate in the cecum (P = 0.01). Activation of breast muscle p70S6 kinase was higher when ALM was included in a dose-dependent manner (P < 0.01). The inclusion of ALM increased breast meat redness (P < 0.01); however, the lightness was within the normal range in all groups. Findings from our study suggest that ALM could be included in a broiler chicken diet up to 5% without any major negative effect on meat quality or performance, and it regulates muscle protein synthesis through activation of mammalian target of rapamycin/6S kinase signaling.     

Meat quality of farmed red deer fed a balanced diet: effects of supplementation with copper bolus on different muscles

Supplementation with copper (Cu) improves deer antler characteristics, but it could modify meat quality and increase its Cu content to levels potentially harmful for humans. Here, we studied the effects of Cu bolus supplementation by means on quality and composition of sternocephalicus (ST) and rectus abdominis (RA) muscles (n=13 for each one) from yearling male red deer fed with a balanced diet. Each intraruminal bolus, containing 3.4 g of Cu, was administered orally in the treatment group to compare with the control group. Meat traits studied were pH at 24 h postmortem (pH₂₄), colour, chemical composition, cholesterol content, fatty acid (FA) composition, amino acid (AA) profile and mineral content. In addition, the effect of Cu supplementation on mineral composition of liver and serum (at 0 and 90 days of treatment) was analysed. No interactions between Cu supplementation and muscle were observed for any trait. Supplementation with Cu increased the protein content of meat (P<0.01). However, Cu content of meat, liver and serum was not modified by supplementation. In fact, Cu content of meat (1.20 and 1.34 mg/kg for Cu supplemented and control deer, respectively) was much lower in both groups than 5 mg/kg of fresh weight allowed legally for food of animal origin. However, bolus of Cu tended to increase the meat content of zinc and significantly increased (P<0.05) the hepatic contents of sodium and lead. Muscles studied had different composition and characteristics. The RA muscle had significantly higher protein content (P<0.001), monounsaturated FA content (P<0.05) and essential/non-essential AA ratio (P<0.01) but lower pH₂₄ (P<0.01) and polyunsaturated FA content (P=0.001) than the ST muscle. In addition, RA muscle had 14.4% less cholesterol (P=0.001) than ST muscle. Also, mineral profile differed between muscles with higher content of iron, significantly higher (P<0.001) content of zinc and lower content of calcium, magnesium and phosphorus (P<0.05) for ST muscle compared with RA. Therefore, supplementation with Cu modified deer meat characteristics, but it did not increase its concentration to toxic levels, making it a safe practice from this perspective. Despite the lower content of polyunsaturated FA, quality was better for RA than for ST muscle based on its higher content of protein with more essential/non-essential AA ratio and lower pH₂₄ and cholesterol content.     

Identification of heat shock protein gene expression in hair follicles as a novel indicator of heat stress in beef calves

Heat shock proteins (HSPs) consist of highly preserved stress proteins that are expressed in response to stress. Two studies were carried out to investigate whether HSP genes in hair follicles from beef calves can be suggested as indicators of heat stress (HS). In study 1, hair follicles were harvested from three male Hanwoo calves (aged 172.2 ± 7.20 days) on six dates over the period of 10 April to 9 August 2017. These days provided varying temperature–humidity indices (THIs). In study 2, 16 Hanwoo male calves (aged 169.6 ± 4.60 days, with a BW of 136.9 ± 6.23 kg) were maintained (4 calves per experiment) in environmentally controlled chambers. A completely randomized design with a 2 × 4 factorial arrangement involving two periods (thermoneutral: TN; HS) and four THI treatment groups (threshold: THI = 68 to 70; mild: THI = 74 to 76; moderate THI = 81 to 83; severe: THI = 88 to 90). The calves in the different group were subjected to ambient temperature (22°C) for 7 days (TN) and subsequently to the temperature and humidity corresponding to the target THI level for 21 days (HS). Every three days (at 1400 h) during both the TN and HS periods, the heart rate (HR) and rectal temperature (RT) of each individual were measured, and hair follicles were subsequently collected from the tails of each individual. In study 1, the high variation (P < 0.0001) in THI indicated that the external environment influenced the HS to different extents. The expression levels of the HSP70 and HSP90 genes at the high-THI level were higher (P = 0.0120, P = 0.0002) than those at the low-THI level. In study 2, no differences in the THI (P = 0.2638), HR (P = 0.2181) or RT (P = 0.3846) were found among the groups during the TN period, whereas differences in these indices (P < 0.0001, P < 0.0001 and P < 0.0001, respectively) were observed during the HS period. The expression levels of the HSP70 (P = 0.0010, moderate; P = 0.0065, severe) and HSP90 (P = 0.0040, severe) genes were increased after rapid exposure to heat-stress conditions (moderate and severe levels). We conclude that HSP gene expression in hair follicles provides precise and accurate data for evaluating HS and can be considered a novel indicator of HS in Hanwoo calves maintained in both external and climatic chambers.     

Expression pattern of bta-mir-2898 miRNA and their correlation with heat shock proteins during summer heat stress among native vs crossbred cattle

Earlier studies identified the role of bta-mir-2898 in bovine. Our earlier study identified that, bta-mir-2898 can be over expressed in crossbred cattle during heat stress. Nevertheless the differential expression of bta-mir-2898 among native vs crossbred cattle during summer stress along with it's correlation with different heat shock proteins (HSPs) is not yet studied. In the present context, we studied the differential expression of bta-mir-2898 among Frieswal (Bos indicus x Bos taurus) and Sahiwal (Bos indicus) breeds of cattle during a range of environmental air temperatures and further investigated the correlation of bta-mir-2898 with different HSPs (HSP70, HSP90, HSP60. HSF, HSPB8 and HSP27). It was observed that, at peak air temperature the relative miRNA expression level (p < 0.05) of bta-mir-2898 was 3.4 ± 0.41 and 0.79 ± 0.22 among Frieswal and Sahiwal, respectively. We also observed significant levels (p < 0.05) of mRNA abundance of HSP70, HSP90, HSPB8 and HSP27 among the breeds. In all the cases Sahiwal found to exhibited higher level of HSPs in comparison to Frieswal. Studies revealed that the expression profile of bta-mir-2898 was negatively correlated with the expression of all the HSPs during thermal stress in post anti-mir2898 treated PBMC invitro cultured model originated from both Frieswal and Sahiwal cattle breeds. However, significantly (p < 0.05) higher negative correlations were observed between bta-mir-2898 and HSP70, HSP60 and HSPB8. Present findings highlighted the preliminary role of overexpressed bta-mir-2898 in cattle during thermal stress and its impact on different heat shock proteins.     

Cloning HSP70 and HSP90 genes of kaluga (<Emphasis Type="Italic">Huso dauricus</Emphasis>) and the effects of temperature and salinity stress on their gene expression

The genes encoding HSP70 and HSP90 proteins were isolated from kaluga by homologous cloning and rapid amplification of complementary DNA (cDNA) ends (RACE). HSP70 (GenBank accession no. {"type":"entrez-nucleotide","attrs":{"text":"KP050541","term_id":"756558159","term_text":"KP050541"}}KP050541) and HSP90 (GenBank accession no. {"type":"entrez-nucleotide","attrs":{"text":"KP050542","term_id":"756558161","term_text":"KP050542"}}KP050542) cDNAs were composed of 2275 and 2718 bp and encoded polypeptides of 650 and 725 amino acids, respectively. Basic Local Alignment Search Tool (BLAST) analysis showed that HSP70 and HSP90 of kaluga shared high identities with those of Acipenser ruthenus, Acipenser schrenckii, and Acipenser baerii (98–99 %). Fluorescent real-time RT-PCR under unstressed conditions revealed that HSP70 and HSP90 were expressed in 11 different tissues of kaluga. Messenger RNA (mRNA) expressions of both HSP70 and HSP90 were highest in the intestine and lowest in the muscle. In addition, the patterns of mRNA expression of HSP70 and HSP90 were similar, although the level of expression was more in HSP90 than in HSP70 (P < 0.05).We also analyzed patterns of HSP70 and HSP90 expression in the muscle, gill, and liver of kaluga under different combinations of temperature and salinity stress, including temperatures of 4,10, 25, and 28 °C at 0 ppt salinity, and salinities of 10, 20, 30, and 40 ppt at 16 °C, where 16 °C at 0 ppt (parts per thousand) served as the control. We found that levels of mRNA expression of both HSP70 and HSP90 were highest at 4 °C in the muscle, gill, and liver and changed little with salinity stress. These results increase understanding of the mechanisms of stress response of cold freshwater fish.     

Serum levels of HSP70 and other DAMP proteins can aid in patient diagnosis after traumatic injury

Danger-associated molecular patterns (DAMPs) are activated by endogenous signals that originate from stressed, injured, or necrotic cells, signifying “danger” to the host. In this study, we evaluated the expression of the DAMP heat shock protein 70 (HSP70) in trauma patients with and without secondary infections. Levels of glucose (GLU), procalcitonin (PCT), total cholesterol (T-Chol), and white blood cell (WBC) counts were also evaluated at three time stages after trauma. Our analysis showed that the levels of serum HSP70 in patients with minor, moderate, and severe injuries were significantly higher than in healthy patients at each time point post-injury (P?<?0.01), and levels of serum HSP70 in the severe injury group were significantly higher than in the minor injury group at 1–6 h after trauma (P?=?0.047). HSP70 was correlated with GLU and was negatively correlated with T-Chol in the period 1–6 h after injury (P?=?0.008/0.032). WBC and GLU were elevated after trauma, with mutual positive correlation (P?<?0.001). PCT levels increased later than WBC counts and GLU levels; these levels were correlated at the two later time periods, 24–48 h and 60–90 h (P?=?0.008/0.041). PCT continued to rise in patients with secondary infection, but PCT dropped at the third time period in patients without secondary infection. In summary, our results suggest that danger and stress theory can be used to predict severity of trauma.     

Effect of thermal stress on HSP70 expression in dermal fibroblast of zebu (Tharparkar) and crossbred (Karan-Fries) cattle

The present studies were conducted to investigate the difference response of dermal fibroblasts to heat stress in Tharparkar and Karan-Fries cattle. Skin is the most important environmental interface providing a protective envelope to animals. In skin, dermal fibroblasts are the most regular cell constituent of dermis that is crucial for temperature homeostasis. The study aimed to examine the reactive oxygen species (ROS) formation, cytotoxicity (%) and heat shock protein 70 (HSP70) genes expression in dermal fibroblast of Tharparkar and Karan-Fries cattle and to assess whether resistance of dermal fibroblast to heat stress is breed specific. Dermal fibroblasts from ear pinna of Tharparkar and Karan-Fries cattle were exposed at 25 °C, 37 °C, 40 °C and 44 °C for 3 h to measure the ROS, cytotoxicity (%) and HSP 70 (HSPA1A, HSPA2 and HSPA8) genes’ expression. The results showed that ROS formation at low temperature (25 °C) decreased in both breeds as compared to control (37 °C) and the differences were significant (P<0.0001). Heat stress at 40 °C did not increase ROS formation significantly in Tharparkar but increased significantly (P<0.001) in Karan-Fries cattle. The overall cytotoxicity (%) was also found to be significantly different (P<0.001) between Tharparkar and Karan-Fries cattle, and on exposure to different temperatures (P<0.001). The cytotoxicity (%) in dermal fibroblast cells of Karan-fries cows was more than Tharparkar. The expression studies indicated that all HSP70 genes (HSPA8, HSPA1A and HSPA2) were up-regulated at different temperatures in both breeds. In Tharparkar, the relative mRNA expression of HSPA8 gene was higher but HSPA1A and HSPA2 genes were low as compared to Karan-Fries cattle. At 40 and 44 °C, the relative expressions of inducible HSP 70 genes (HSPA1A and HSPA2) were higher in Karan-Fries than Tharparkar. In summary, dermal fibroblast resistance to heat shock differed between breeds. Dermal fibroblasts of Tharparkar were observed to be more heat tolerant than crossbred Karan-Fries cattle. The study concludes that zebu cattle (Tharparkar) dermal fibroblasts are more adapted to tropical climatic condition than crossbreed cattle (Karan-Fries). Differences exist in dermal fibroblasts of heat adapted and non-adapted cattle.     

The relationship of pork longissimus muscle pH to mitochondrial respiratory activities,meat quality and muscle structure

The way the pH falls post-slaughter has an impact on meat quality. Pork longissimus muscles (n=48) were sorted in fast- (FG) (n=15) and normal glycolysing (NG) (n=33) muscles according to the post-slaughter pH 45 min values (FG<6.0; NG>6.0). FG muscles (5.84±0.04) compared with NG muscles (6.27±0.04) were accompanied with higher temperature, electrical conductivity, lightness and yellowness, and reduced grill loss and shear force values (P<0.05), but there were no pH-dependent changes of the drip loss and redness results. FG muscles had higher (P<0.05) percentages of fast-twitch glycolytic and lower proportions of fast-twitch oxidative and slow-twitch oxidative (P<0.05) muscle fibres. The study confirms the relationship of pH value to meat quality and muscle fibre characteristics also showing that pH values have no impact on intrinsic mitochondrial respiratory function.     

Expression of heat shock protein 70 in the liver of extensively and intensively kept heavy pigs

The objective of this work was to investigate the expression of heat shock protein 70 (HSP70) by Western blot (WB) in swine liver. Subsequently, the study aimed to apply this method to two experimental groups of heavy pigs raised in different confinement systems: intensive/indoor (Group A) and extensive/outdoor (Group B). Thirty-six crossbred commercial heavy pigs were divided as follows: Group A (eight castrated males and eight females) was equally distributed into two single-sex indoor pens (1.02 m²/pig); Group B (11 castrated males and nine females) was kept in one single (partially grassy and partially wooded) open area of about 6000 m². Group A was slaughtered at 41 weeks of age (170 ± 9 kg) and Group B at 48 weeks of age (172 ± 13 kg). At the abattoir the livers of all the animals were collected and analyzed by WB assay in order to quantify the levels of HSP70. Moreover, a further liver sample was taken from the same animals in order to investigate the cellular localization of HSP70 by immunohistochemistry (IHC). The interaction between sex and group resulted statistically significant (P = 0.001). When stratified by sex, Group A showed significantly higher HSP70 values compared with Group B for both male and female subjects (P < 0.001). Stratifying by group, males showed significantly higher HSP70 values than females in Group A (P < 0.001), whereas no statistical differences were observed between sexes for Group B (P = 0.653). The IHC results evidenced cytoplasmic immunoreactivity in a granular pattern in both groups. The different expression pattern observed by WB could prove to be a useful tool in the assessment of pig health and welfare.