Nine cowsheds were used, the differences between each cowshed are orientation (east-west or north-south), cooling (with or without), and height (3 m, 5 m or 8 m height). Dry-bulb temperature, relative humidity, ...Nine cowsheds were used, the differences between each cowshed are orientation (east-west or north-south), cooling (with or without), and height (3 m, 5 m or 8 m height). Dry-bulb temperature, relative humidity, dew point, shaded area, air velocity, and maximum temperature were measured beneath each shed. The temperature-humidity index (THI) and the shading efficiency were calculated for each cowshed. The trials were conducted using 180 lactating Holstein Friesian cows; twenty cows housed beneath each shade structure. Measurements performed on cows were respiration rate, skin temperature, and rectal temperature; moreover, the milk produced by each cow was recorded, and the feed intake. High air velocities were recorded under high shade structures which enhance the aeration; consequently, maximum temperatures, and THI recorded beneath high sheds were less than those recorded beneath low sheds; also, skin temperatures, and respiration rates for cows housed under high sheds were less than those measured for animals housed under low sheds(differences were found to be significant). Thereby, increasing shed height enhances dairy cows' microclimate under Egyptian conditions (hot climate); consequently, the milk production increases. The best orientation is the east-west orientation, which is preferable for hot climates. The exploitation of cooling has significant effect on microclimate, cooling enhances the ambient environment and provides comfortable zone for dairy cows within which cows reach high production levels.展开更多
The influence of water temperature on protein composition in the reconstitution of milk powder was evaluated using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). 11 ion ...The influence of water temperature on protein composition in the reconstitution of milk powder was evaluated using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). 11 ion peaks in the matrix-assisted laser desorption/ionization (MALDI) spectra were examined to study the alteration of relative quantities of milk proteins when water at different temperature was employed in the reconstitution of milk powder. A discrepancy factor Dij was implemented to represent the degree of milk proteins' denaturation. Data obtained indicated that Dij value increased with rising water temperature, and thermal damage to milk proteins became evidently when the water temperature exceeded 60℃. The results confirmed that nutrient loss occurred when milk proteins denatured in water at high temperatures.展开更多
Biohydrogen production from synthetic waste, SW (model organic fraction of municipal solid waste) co-digested with liquid dairy manure (M) was tested in batch reactions to assess the effect of temperature and mixi...Biohydrogen production from synthetic waste, SW (model organic fraction of municipal solid waste) co-digested with liquid dairy manure (M) was tested in batch reactions to assess the effect of temperature and mixing ratio of the substrates. A 5 × 2 factorial design experiment was conducted. Synthetic waste: manure mixtures of 1:1, 2:1, 3:1, 1:0, 0:1 (volatile solids, VS, basis) were tested at 37 (T37) and 55 ℃ (T55) using thirty 1 L laboratory scale digesters. Total VS of each mixture was 50 g/L except SW:M 0:I treatment, where total VS was 27.4 g/L. Gas samples were taken daily to determine hydrogen production, and slurry samples taken before and after experimentation, were analyzed for volatile fatty acid (VFA) concentration, volatile solid (VS) degradation, ammonium nitrogen (NH4+-N) and pH. Hydrogen production (mL/g-VS fed) showed a significant two-factor interaction between incubation temperature and SW:M ratio (P 〈 0.001). Maximum production of 15.8 mL/g-VS (fed) was achieved in SW:M ratio of 3:1 at 55 ℃. Generally, hydrogen productions at thermophilic temperature (T55) were significantly higher than at mesophilic (T37) temperature for all treatments (P 〈 0.001) except for SW:M 1:0 and SW:M 0:1 treatments (P 〉 0.05). This study indicates that hydrogen production from co-digestion of synthetic waste and manure is dependent on incubation temperature and relative contribution of wastes in the mixture.展开更多
The occurrence of the spore-forming bacteria in different segments of production lines of Ultra High Temperature (UHT) milk of a commercial plant and its transfer to the final product was studied. The samples were c...The occurrence of the spore-forming bacteria in different segments of production lines of Ultra High Temperature (UHT) milk of a commercial plant and its transfer to the final product was studied. The samples were collected from different segments of production lines from reception to packaging sections, over a period of 75 days at a rate of one sampling a week, from plants in North West of Algeria. The total colony count of aerobic spore-forming bacteria was done using Plate Count Agar (PCA) method. The results showed that there was more than 1 ×10^3 CFU/mL at the level of 50%, 25%, 37.5%, 62.5% and 37.5% of the analyzed samples of milk powder, pasteurized milk, UHT milk (before storage), UHT milk stored at 55℃ for 7 days and UHT milk stored at 30℃ for 14 days, respectively. The mean total colony count of aerobic spore-forming bacteria was considerably lower in the UHT milk than in the other samples, while the higher proportion of aerobic spore-forming bacteria was noticed to be 32.58% and 30.90% in the UHT milk stored at 55℃ and 30℃, respectively. The results obtained by the classic biochemical identification (Bacillus API 20E), interpreted by software of calculation for microbial identification reflected the presence of especially Bacillus sphaericus. The other species found were: Bacillus cereus, Bacillus subtilis, Bacillus coagulans, Bacillus licheniformis and Bacillus stearothermophilus. The study reveals that the proportion of aerobic spore-forming bacteria in the final product depends on temperature and storage periods.展开更多
Recent studies have suggested that there may be a link between the use of in-feed antibiotics and the prevalence of antibiotic-resistant bacteria in human infections. It is believed that anaerobic digestion is a poten...Recent studies have suggested that there may be a link between the use of in-feed antibiotics and the prevalence of antibiotic-resistant bacteria in human infections. It is believed that anaerobic digestion is a potent method to reduce the antibiotic resistant bacteria present in waste from concentrated animal feeding operations. Cefazolin is a β-1actam antibiotic that is frequently used to treat the cows with mastitis in the Obihiro University herd. Disposal of untreated milk containing cefazolin residues promotes the occurrence of cefazolin resistant bacteria in the vicinity of farm, thus the objective of this study was to investigate the survival of antibiotic resistant bacteria in co-digestion of dairy manure and waste milk obtained from cows treated for mastitis with cefazolin under thermophilic conditions (55 ~C). Cow manure, digested slurry and waste milk (cefazolin residue concentration 2.17 mg/L) were used as the materials in order to have three digester contents; 100% slurry, 50% slurry + 50% manure and 50% slurry + 45% manure + 5% waste milk. The experiment was carried out using batch digesters (1 L) with active volume of 800 mL at 55 ℃ for 20 days to determine the survival of cefazolin resistant bacteria and to observe the digester performance by determining the bio gas and methane yield using gas chromatpgrapby. Dilution plate method was used to determine the population densities of total and cefazolin resistant bacteria at 0, 10th and 20th day of digestion. Total and cefazolin resistant bacterial counts were reduced with time by several orders until 10th day of digestion and those were almost similar at day 20th. Highest daily biogas and methane yield were observed in the digester contained slurry, manure and waste milk during early digestion period (until 5th day). The results suggest that thermophilic co-digestion of dairy manure and waste milk would be a suitable technology for reducing antibiotic (cefazolin) resistant bacteria while obtaining better digester performance.展开更多
Pistachio nut cream is a new product that was produced by mixing powdered sugar, roasted pistachio nut, defatted powdered milk, lecithin, vanilla and margarine. Pistachio nut cream was stored at 4 and 20 °C in se...Pistachio nut cream is a new product that was produced by mixing powdered sugar, roasted pistachio nut, defatted powdered milk, lecithin, vanilla and margarine. Pistachio nut cream was stored at 4 and 20 °C in sealed jars. Nut creams were analyzed by chemical analysis such as peroxide values (meq kgt), total and free fatty acidity (%), moisture content (%), pH, 2-tiobarbutric acid and browning indices. Sensory evaluations of the cream were examined according to the color, odour, texture, taste, aroma and feelings by the panelists. Samples containing 10% and 15% pistachio nut that were stored at 4 °C were better and more acceptable with respect to the chemical properties of pistachio nut cream compared to the nut cream samples that were stored at 20 °C.展开更多
A uniform and effective heat distribution inside the canned milk is very crucial for achieving effective sterilization. It is extremely difficult to establish the temperature profile inside the canned milk during cont...A uniform and effective heat distribution inside the canned milk is very crucial for achieving effective sterilization. It is extremely difficult to establish the temperature profile inside the canned milk during continuous industrial scale operation. Computational fluid dynamics (CFD) simulation can be a useful tool to determine the temperature distribution of the fluid inside the can during the sterilization process. A CFD model was developed for the sterilization of canned milk at 121 ~C. The simulation results were validated with the experimental measurements of temperatures. The formation and movement of slowest heating zone (SHZ) during the sterilization process was tracked. Moreover, effect of can position (vertical and horizontal) during processing on milk temperature distribution inside the can was also investigated. Higher Grashof and Rayleigh numbers were obtained for vertical positioning of can compared to horizontal can processing. Further, effectiveness of the process was calculated based on F-value and these results reinforced the positive effect of horizontal position of can during the sterilization process.展开更多
[Objective] This study aimed to estimate the genetic parameters for milk yield, fat percentage, fat yield and age at first freshening of Chinese Holsteins first lactation cows in Heilongjiang under frigid-temperature ...[Objective] This study aimed to estimate the genetic parameters for milk yield, fat percentage, fat yield and age at first freshening of Chinese Holsteins first lactation cows in Heilongjiang under frigid-temperature and temperature zone. [Method] Records of yield and reproduction from 8 868 Chinese Holstein first lacta- tion cows from 21 herds were utilized to evaluate genetic parameters for Hei- Iongjiangs' Chinese Holsteins. Restricted maximum likelihood (REML) method was used with an animal model. [Result] The heritabilities were 0.16 to 0.34 for yields and fat percentage, 0.38 for reproduction (age at the first freshening), which were similar to estimates for temperate areas from similar methods, except for constituent percentage. Also, the estimates of genetic correlation were high between milk yield and fat yield (0.97), but were low between milk yield and fat percentage (-0.24), age at the first freshening (-0.29) and generally antagonistic. [Conclusion] Thus, es- timates of genetic parameters in this frigid and frigid-temperate environment did not differ appreciably from those that occur in temperate dairy areas.展开更多
Several food companies are implementing effective strategies to evaluate the environmental impacts of their products or processes and to estimate the greenhouse gases emissions (GHG) using a life cycle approach. Par...Several food companies are implementing effective strategies to evaluate the environmental impacts of their products or processes and to estimate the greenhouse gases emissions (GHG) using a life cycle approach. Particularly, a sector which can play an important role to reduce the impact on the environment through the life cycle thinking is the beverage packaging. In this context, the aim of this study was to use the life cycle assessment (LCA) method to investigate the consistency of the preference order across two alternative beverage packages through the application of two impact assessment methods, namely the IPCC 2007 which is focused on the GHG emissions estimation and the EcoIndicator 99 which considers several environmental categories including impact on climate change. The results showed that the life cycle approach employment was a useful strategy to investigate the consistency of the preference order across two beverage packages, especially, whether the results are made more reliable by the utilization of primary data. The investigation on climate change conducted on two level, initially, the quantification of the GHG emissions and secondly the estimation of the related diseases and mortality, demonstrated that the laminated carton presents lower impacts than the high-density polyethylene (HDPE) bottle.展开更多
Heat stress affects feed intake, milk production, and endocrine status in dairy cows. The temperaturehumidity index(THI) is employed as an index to evaluate the degree of heat stress in dairy cows. However, it is di...Heat stress affects feed intake, milk production, and endocrine status in dairy cows. The temperaturehumidity index(THI) is employed as an index to evaluate the degree of heat stress in dairy cows. However, it is difficult to ascertain whether THI is the most appropriate measurement of heat stress in dairy cows. This experiment was conducted to investigate the effects of heat stress on serum insulin, adipokines(leptin and adiponectin), AMP-activated protein kinase(AMPK), and heat shock signal molecules(heat shock transcription factor(HSF) and heat shock proteins(HSP)) in dairy cows and to research biomarkers to be used for better understanding the meaning of THI as a bioclimatic index. To achieve these objectives, two experiments were performed. The first experiment: eighteen lactating Holstein dairy cows were used. The treatments were: heat stress(HS, THI average=81.7, n=9) and cooling(CL, THI average=53.4, n=9). Samples of HS were obtained on August 16, 2013, and samples of CL were collected on April 7, 2014 in natural conditions. The second experiment: HS treatment cows(n=9) from the first experiment were fed for 8 weeks from August 16, 2013 to October 12, 2013. Samples for moderate heat stress, mild heat stress, and no heat stress were obtained, respectively, according to the physical alterations of the THI. Results showed that heat stress significantly increased the serum adiponectin, AMPK, HSF, HSP27, HSP70, and HSP90(P〈0.05). Adiponectin is strongly associated with AMPK. The increases of adiponectin and AMPK may be one of the mechanisms to maintain homeostasis in heat-stressed dairy cows. When heat stress treatment lasted 8 weeks, a higher expression of HSF and HSP70 was observed under moderate heat stress. Serum HSF and HSP70 are sensitive and accurate in heat stress and they could be potential indicators of animal response to heat stress. We recommend serum HSF and HSP70 as meaningful biomarkers to supplement the THI and evaluate moderate heat stress in dairy cows in the future.展开更多
文摘Nine cowsheds were used, the differences between each cowshed are orientation (east-west or north-south), cooling (with or without), and height (3 m, 5 m or 8 m height). Dry-bulb temperature, relative humidity, dew point, shaded area, air velocity, and maximum temperature were measured beneath each shed. The temperature-humidity index (THI) and the shading efficiency were calculated for each cowshed. The trials were conducted using 180 lactating Holstein Friesian cows; twenty cows housed beneath each shade structure. Measurements performed on cows were respiration rate, skin temperature, and rectal temperature; moreover, the milk produced by each cow was recorded, and the feed intake. High air velocities were recorded under high shade structures which enhance the aeration; consequently, maximum temperatures, and THI recorded beneath high sheds were less than those recorded beneath low sheds; also, skin temperatures, and respiration rates for cows housed under high sheds were less than those measured for animals housed under low sheds(differences were found to be significant). Thereby, increasing shed height enhances dairy cows' microclimate under Egyptian conditions (hot climate); consequently, the milk production increases. The best orientation is the east-west orientation, which is preferable for hot climates. The exploitation of cooling has significant effect on microclimate, cooling enhances the ambient environment and provides comfortable zone for dairy cows within which cows reach high production levels.
文摘The influence of water temperature on protein composition in the reconstitution of milk powder was evaluated using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). 11 ion peaks in the matrix-assisted laser desorption/ionization (MALDI) spectra were examined to study the alteration of relative quantities of milk proteins when water at different temperature was employed in the reconstitution of milk powder. A discrepancy factor Dij was implemented to represent the degree of milk proteins' denaturation. Data obtained indicated that Dij value increased with rising water temperature, and thermal damage to milk proteins became evidently when the water temperature exceeded 60℃. The results confirmed that nutrient loss occurred when milk proteins denatured in water at high temperatures.
文摘Biohydrogen production from synthetic waste, SW (model organic fraction of municipal solid waste) co-digested with liquid dairy manure (M) was tested in batch reactions to assess the effect of temperature and mixing ratio of the substrates. A 5 × 2 factorial design experiment was conducted. Synthetic waste: manure mixtures of 1:1, 2:1, 3:1, 1:0, 0:1 (volatile solids, VS, basis) were tested at 37 (T37) and 55 ℃ (T55) using thirty 1 L laboratory scale digesters. Total VS of each mixture was 50 g/L except SW:M 0:I treatment, where total VS was 27.4 g/L. Gas samples were taken daily to determine hydrogen production, and slurry samples taken before and after experimentation, were analyzed for volatile fatty acid (VFA) concentration, volatile solid (VS) degradation, ammonium nitrogen (NH4+-N) and pH. Hydrogen production (mL/g-VS fed) showed a significant two-factor interaction between incubation temperature and SW:M ratio (P 〈 0.001). Maximum production of 15.8 mL/g-VS (fed) was achieved in SW:M ratio of 3:1 at 55 ℃. Generally, hydrogen productions at thermophilic temperature (T55) were significantly higher than at mesophilic (T37) temperature for all treatments (P 〈 0.001) except for SW:M 1:0 and SW:M 0:1 treatments (P 〉 0.05). This study indicates that hydrogen production from co-digestion of synthetic waste and manure is dependent on incubation temperature and relative contribution of wastes in the mixture.
文摘The occurrence of the spore-forming bacteria in different segments of production lines of Ultra High Temperature (UHT) milk of a commercial plant and its transfer to the final product was studied. The samples were collected from different segments of production lines from reception to packaging sections, over a period of 75 days at a rate of one sampling a week, from plants in North West of Algeria. The total colony count of aerobic spore-forming bacteria was done using Plate Count Agar (PCA) method. The results showed that there was more than 1 ×10^3 CFU/mL at the level of 50%, 25%, 37.5%, 62.5% and 37.5% of the analyzed samples of milk powder, pasteurized milk, UHT milk (before storage), UHT milk stored at 55℃ for 7 days and UHT milk stored at 30℃ for 14 days, respectively. The mean total colony count of aerobic spore-forming bacteria was considerably lower in the UHT milk than in the other samples, while the higher proportion of aerobic spore-forming bacteria was noticed to be 32.58% and 30.90% in the UHT milk stored at 55℃ and 30℃, respectively. The results obtained by the classic biochemical identification (Bacillus API 20E), interpreted by software of calculation for microbial identification reflected the presence of especially Bacillus sphaericus. The other species found were: Bacillus cereus, Bacillus subtilis, Bacillus coagulans, Bacillus licheniformis and Bacillus stearothermophilus. The study reveals that the proportion of aerobic spore-forming bacteria in the final product depends on temperature and storage periods.
文摘Recent studies have suggested that there may be a link between the use of in-feed antibiotics and the prevalence of antibiotic-resistant bacteria in human infections. It is believed that anaerobic digestion is a potent method to reduce the antibiotic resistant bacteria present in waste from concentrated animal feeding operations. Cefazolin is a β-1actam antibiotic that is frequently used to treat the cows with mastitis in the Obihiro University herd. Disposal of untreated milk containing cefazolin residues promotes the occurrence of cefazolin resistant bacteria in the vicinity of farm, thus the objective of this study was to investigate the survival of antibiotic resistant bacteria in co-digestion of dairy manure and waste milk obtained from cows treated for mastitis with cefazolin under thermophilic conditions (55 ~C). Cow manure, digested slurry and waste milk (cefazolin residue concentration 2.17 mg/L) were used as the materials in order to have three digester contents; 100% slurry, 50% slurry + 50% manure and 50% slurry + 45% manure + 5% waste milk. The experiment was carried out using batch digesters (1 L) with active volume of 800 mL at 55 ℃ for 20 days to determine the survival of cefazolin resistant bacteria and to observe the digester performance by determining the bio gas and methane yield using gas chromatpgrapby. Dilution plate method was used to determine the population densities of total and cefazolin resistant bacteria at 0, 10th and 20th day of digestion. Total and cefazolin resistant bacterial counts were reduced with time by several orders until 10th day of digestion and those were almost similar at day 20th. Highest daily biogas and methane yield were observed in the digester contained slurry, manure and waste milk during early digestion period (until 5th day). The results suggest that thermophilic co-digestion of dairy manure and waste milk would be a suitable technology for reducing antibiotic (cefazolin) resistant bacteria while obtaining better digester performance.
文摘Pistachio nut cream is a new product that was produced by mixing powdered sugar, roasted pistachio nut, defatted powdered milk, lecithin, vanilla and margarine. Pistachio nut cream was stored at 4 and 20 °C in sealed jars. Nut creams were analyzed by chemical analysis such as peroxide values (meq kgt), total and free fatty acidity (%), moisture content (%), pH, 2-tiobarbutric acid and browning indices. Sensory evaluations of the cream were examined according to the color, odour, texture, taste, aroma and feelings by the panelists. Samples containing 10% and 15% pistachio nut that were stored at 4 °C were better and more acceptable with respect to the chemical properties of pistachio nut cream compared to the nut cream samples that were stored at 20 °C.
文摘A uniform and effective heat distribution inside the canned milk is very crucial for achieving effective sterilization. It is extremely difficult to establish the temperature profile inside the canned milk during continuous industrial scale operation. Computational fluid dynamics (CFD) simulation can be a useful tool to determine the temperature distribution of the fluid inside the can during the sterilization process. A CFD model was developed for the sterilization of canned milk at 121 ~C. The simulation results were validated with the experimental measurements of temperatures. The formation and movement of slowest heating zone (SHZ) during the sterilization process was tracked. Moreover, effect of can position (vertical and horizontal) during processing on milk temperature distribution inside the can was also investigated. Higher Grashof and Rayleigh numbers were obtained for vertical positioning of can compared to horizontal can processing. Further, effectiveness of the process was calculated based on F-value and these results reinforced the positive effect of horizontal position of can during the sterilization process.
文摘[Objective] This study aimed to estimate the genetic parameters for milk yield, fat percentage, fat yield and age at first freshening of Chinese Holsteins first lactation cows in Heilongjiang under frigid-temperature and temperature zone. [Method] Records of yield and reproduction from 8 868 Chinese Holstein first lacta- tion cows from 21 herds were utilized to evaluate genetic parameters for Hei- Iongjiangs' Chinese Holsteins. Restricted maximum likelihood (REML) method was used with an animal model. [Result] The heritabilities were 0.16 to 0.34 for yields and fat percentage, 0.38 for reproduction (age at the first freshening), which were similar to estimates for temperate areas from similar methods, except for constituent percentage. Also, the estimates of genetic correlation were high between milk yield and fat yield (0.97), but were low between milk yield and fat percentage (-0.24), age at the first freshening (-0.29) and generally antagonistic. [Conclusion] Thus, es- timates of genetic parameters in this frigid and frigid-temperate environment did not differ appreciably from those that occur in temperate dairy areas.
文摘Several food companies are implementing effective strategies to evaluate the environmental impacts of their products or processes and to estimate the greenhouse gases emissions (GHG) using a life cycle approach. Particularly, a sector which can play an important role to reduce the impact on the environment through the life cycle thinking is the beverage packaging. In this context, the aim of this study was to use the life cycle assessment (LCA) method to investigate the consistency of the preference order across two alternative beverage packages through the application of two impact assessment methods, namely the IPCC 2007 which is focused on the GHG emissions estimation and the EcoIndicator 99 which considers several environmental categories including impact on climate change. The results showed that the life cycle approach employment was a useful strategy to investigate the consistency of the preference order across two beverage packages, especially, whether the results are made more reliable by the utilization of primary data. The investigation on climate change conducted on two level, initially, the quantification of the GHG emissions and secondly the estimation of the related diseases and mortality, demonstrated that the laminated carton presents lower impacts than the high-density polyethylene (HDPE) bottle.
基金Project supported by the National Basic Research Program(973)of China(No.2011CB100805)the Modern Agro-Industry Technology Research System of China(No.nycytx-04-01)the Agricultural Science and Technology Innovation Program(No.ASTIP-IAS12),China
文摘Heat stress affects feed intake, milk production, and endocrine status in dairy cows. The temperaturehumidity index(THI) is employed as an index to evaluate the degree of heat stress in dairy cows. However, it is difficult to ascertain whether THI is the most appropriate measurement of heat stress in dairy cows. This experiment was conducted to investigate the effects of heat stress on serum insulin, adipokines(leptin and adiponectin), AMP-activated protein kinase(AMPK), and heat shock signal molecules(heat shock transcription factor(HSF) and heat shock proteins(HSP)) in dairy cows and to research biomarkers to be used for better understanding the meaning of THI as a bioclimatic index. To achieve these objectives, two experiments were performed. The first experiment: eighteen lactating Holstein dairy cows were used. The treatments were: heat stress(HS, THI average=81.7, n=9) and cooling(CL, THI average=53.4, n=9). Samples of HS were obtained on August 16, 2013, and samples of CL were collected on April 7, 2014 in natural conditions. The second experiment: HS treatment cows(n=9) from the first experiment were fed for 8 weeks from August 16, 2013 to October 12, 2013. Samples for moderate heat stress, mild heat stress, and no heat stress were obtained, respectively, according to the physical alterations of the THI. Results showed that heat stress significantly increased the serum adiponectin, AMPK, HSF, HSP27, HSP70, and HSP90(P〈0.05). Adiponectin is strongly associated with AMPK. The increases of adiponectin and AMPK may be one of the mechanisms to maintain homeostasis in heat-stressed dairy cows. When heat stress treatment lasted 8 weeks, a higher expression of HSF and HSP70 was observed under moderate heat stress. Serum HSF and HSP70 are sensitive and accurate in heat stress and they could be potential indicators of animal response to heat stress. We recommend serum HSF and HSP70 as meaningful biomarkers to supplement the THI and evaluate moderate heat stress in dairy cows in the future.