China Dairy ›› 2026, Vol. 0 ›› Issue (6): 75-82.doi: 10.12377/1671-4393.26.06.09

• HEAT STRESS REPRODUCTION • Previous Articles     Next Articles

Impact and Mechanisms of Heat Stress on Survival of Early Embryos in Dairy Cows

GU Sukun1, ZHU Qingli2, ZHAO Shanjiang2, ZHU Huabin2, LI Zhijia1, PAN Bing1, ZHAO Huiqiu1,*   

  1. 1. Hebei Provincial Animal Husbandry Station,Shijiazhuang Hebei 050035;
    2. Institute of Animal Sciences,Chinese Academy of Agricultural Sciences,Beijing 100193
  • Online:2026-06-25 Published:2026-07-22

Abstract: Heat stress is a critical environmental factor impairing reproductive performance in dairy cows during summer, with particularly detrimental effects on early embryonic survival. This review systematically summarized the impacts and underlying mechanisms of heat stress on early embryo survival in dairy cows. It begins by outlining the assessment indicators of heat stress and its multifaceted reproductive consequences, including abnormal estrus, reduced fertilization rates, and increased embryonic mortality. The mechanisms are then analyzed from both maternal and embryonic perspectives. On the maternal side, heat stress disrupts the hypothalamic-pituitary-ovarian axis, elevates reproductive tract temperature, and alters uterine blood flow and endometrial secretory functions, thereby compromising the embryonic microenvironment. On the embryonic side, heat stress induces oocyte aging, interferes with embryonic genome activation, triggers apoptosis, and disturbs redox homeostasis, with embryonic stage and genotype playing key roles in differential thermotolerance. Furthermore, this review summarized commonly applied interventions in dairy production, such as timed ovulation-fixed-time insemination, GnRH/hCG administration, and progesterone supplementation, aimed at mitigating the negative effects of heat stress on embryo survival. This review aimed to provide both theoretical foundations and practical strategies for improving dairy cow reproductive performance during hot seasons.

Key words: heat stress, dairy cow, early embryos, impact, mechanisms

[1] Roenfeldt S .You can't afford to ignore heat stress[J].Dairy Herd Management,1998,35.
[2] 中华人民共和国农业行业标准.NY/T2363-2013 奶牛热应激评价技术规范[S].
[3] 李建国,桑润滋,张正珊,等. 热应激对奶牛生理常值、血液生化指标、繁殖及泌乳性能的影响[J]. 河北农业大学学报,1998(4):69-75.
[4] Kadzere C T,Murphy M R,Silanikove N,et al.Heat stress in lactating dairy cows:A review[J]. Livestock Production Science,2002,1(77):59-91.
[5] 周学军,许永才,张贵强. 南京某奶牛场奶牛胎衣不下病因及防治效果浅析[C].中国山东青岛,2010.
[6] 李玉霞. 奶牛胎衣不下发生情况及原因分析[C]. 中国山东青岛,2010.
[7] Roth Z.Reproductive physiology and endocrinology responses of cows exposed to environmental heat stress-Experiences from the past and lessons for the present[J]. Theriogenology,2020,155:150-156.
[8] 张航,杨柏高,徐茜,等. 热应激影响奶牛胚胎发育作用机制的研究进展[J]. 畜牧兽医学报,2023,54(7):2692-2700.
[9] 王九峰,韩博,苏敬良,等.牛病学–疾病与管理[M]. 第2版.中国农业大学出版社,2006
[10] 侯秀贤,朱化彬,郝海生,等. 热应激对奶牛繁殖性能的影响及其防治措施[J]. 中国奶牛,2010(11):25-28.
[11] 赵德明,沈建中. 奶牛疾病学[M]. 中国农业大学出版社,2002.
[12] Roth Z,Meidan R,Braw-Tal R,et al.Immediate and delayed effects of heat stress on follicular development and its association with plasma FSH and inhibin concentration in cows[J]. Journal of Reproduction and Fertility,2000,120(1):83-90.
[13] Roman-Ponce H,Thatcher WW,Canton D,et al Thermal stress efects on uterine blood flow in dairy cows[J]. Journal of Animal Science,1978,46:175-80.
[14] Gwazdauskas FC,Wilcox CJ,Thatcher WW.Environmental and management factors affecting conception rate in a subtropical climate[J].Journal of Dairy Science,1975,58:88-92.
[15] Rivera RM,Hansen PJ.Development of cultured bovine embryos after exposure to high temperatures in the physiological range[J]. Reproduction,2001,121:107-15.
[16] Edwards J L,Hansen P J.Differential responses of bovine oocytes and preimplantation embryos to heat shock[J]. Molecular Reproduction and Development,1997,46(2):138-145.
[17] Rocha A,Randel R D,Broussard J R,et al.High environmental temperature and humidity decrease oocyte quality in Bos taurus but not in Bos indicus cows[J]. Theriogenology,1998,49(3):657-665.
[18] Wolfenson D,Roth Z,Meidan R. Impaired reproduction in heat-stressed cattle:basic and applied aspects[J]. Animal Reproduction Science,2000,60-61:535-547.
[19] Wolfenson D,Flamenbaum I,Berman A.Hyperthermia and body energy store effects on estrous behavior,conception rate,and corpus luteum function in dairy cows[J]. Journal of Dairy Science,1988,71(12):3497-3504.
[20] Roth Z.Heat stress,the follicle,and its enclosed oocyte:mechanisms and potential strategies to improve fertility in dairy cows[J]. Reproduction in Domestic Animals,2008,43(Suppl 2):238-244.
[21] Mihm M,Baguisi A,Boland M P,et al.Association between the duration of dominance of the ovulatory follicle and pregnancy rate in beef heifers[J]. Journal of Reproduction and Fertility,1994,102(1):123-130.
[22] Austin E J,Mihm M,Ryan M P,et al.Effect of duration of dominance of the ovulatory follicle on onset of estrus and fertility in heifers[J]. Journal of Animal Science,1999,77(8):2219-2226.
[23] Guzeloglu A,Ambrose J D,Kassa T,et al.Long-term follicular dynamics and biochemical characteristics of dominant follicles in dairy cows subjected to acute heat stress[J]. Animal Reproduction Science,2001,66(1-2):15-34.
[24] Roth Z,Arav A,Bor A,et al.Improvement of quality of oocytes collected in the autumn by enhanced removal of impaired follicles from previously heat-stressed cows[J]. Reproduction (Cambridge,England),2001,122(5):737-744.
[25] Hansen P J.Exploitation of genetic and physiological determinants of embryonic resistance to elevated temperature to improve embryonic survival in dairy cattle during heat stress[J]. Theriogenology,2007,68(Suppl 1):S242-S249.
[26] Putney D J,Drost M,Thatcher W W.Embryonic development in superovulated dairy cattle exposed to elevated ambient temperatures between Days 1 to 7 post insemination[J]. Theriogenology,1988,30(2):195-209.
[27] Ju J C,Jiang S,Tseng J K,et al.Heat shock reduces developmental competence and alters spindle configuration of bovine oocytes[J]. Theriogenology,2005,64(8):1677-1689.
[28] Hansen P J.To be or not to be--determinants of embryonic survival following heat shock[J]. Theriogenology,2007,68(Suppl 1):S40-S48.
[29] Krininger C E R,Block J,Al-Katanani Y M,et al. Differences between Brahman and Holstein cows in response to estrus synchronization,superovulation and resistance of embryos to heat shock[J]. Animal Reproduction Science,2003,78(1-2):13-24.
[30] 吴珑韬. 中国荷斯坦奶牛HSP70-1基因多态性与耐热性能相关性分析[D]. 福州:福建农林大学,2015.
[31] Hansen P J.Prospects for gene introgression or gene editing as a strategy for reduction of the impact of heat stress on production and reproduction in cattle[J]. Theriogenology,2020,154:190-202.
[32] Ealy A D,Hansen P J.Induced thermotolerance during early development of murine and bovine embryos[J]. Journal of Cellular Physiology,1994,160(3):463-468.
[33] Brodsky J L,Chiosis G.Hsp70 molecular chaperones:emerging roles in human disease and identification of small molecule modulators[J]. Current Topics in Medicinal Chemistry,2006,11(6):1215-1225.
[34] Al-Katanani Y M,Hansen P J. Induced thermotolerance in bovine two-cell embryos and the role of heat shock protein 70 in embryonic development[J]. Molecular Reproduction and Development,2002,62(2):174-180.
[35] Edwards J L,Hansen P J.Elevated temperature increases heat shock protein 70 synthesis in bovine two-cell embryos and compromises function of maturing oocytes[J]. Biology of Reproduction,1996,55(2):341-346.
[36] Paula-Lopes F F,Hansen P J. Apoptosis is an adaptive response in bovine preimplantation embryos that facilitates survival after heat shock[J]. Biochemical and Biophysical Research Communications,2002,1(295):37-42.
[37] Grütter M G.Caspases:key players in programmed cell death[J]. Current Opinion in Structural Biology,2000,10(6):649-655.
[38] Chang H Y,Yang X.Proteases for cell suicide:functions and regulation of caspases[J]. Microbiology and Molecular Biology Reviews,2000,64(4):821-846.
[39] Ozawa M,Hirabayashi M,Kanai Y.Developmental competence and oxidative state of mouse zygotes heat-stressed maternally or in vitro[J]. Reproduction,2002,5(124):683-689.
[40] Matsuzuka T,Sakamoto N,Ozawa M,et al.Alleviation of maternal hyperthermia-induced early embryonic death by administration of melatonin to mice[J]. Journal of Pineal Research,2005,39(3):217-223.
[41] Roth Z,Wolfenson D.Comparing the effects of heat stress and mastitis on ovarian function in lactating cows:basic and applied aspects[J]. Domestic Animal Endocrinology,2016,56(S):S218-S227.
[42] Sakatani M,Kobayashi S I,Takahashi M.Effects of heat shock on in vitro development and intracellular oxidative state of bovine preimplantation embryos[J]. Molecular Reproduction and Development,2004,67(1):77-82.
[43] de la Sota R L,Burke J M,Risco C A,et al. Evaluation of timed insemination during summer heat stress in lactating dairy cattle[J]. Theriogenology,1998,49(4):761-770.
[44] Kaim M,Bloch A,Wolfenson D,et al.Effects of GnRH administered to cows at the onset of estrus on timing of ovulation,endocrine responses,and conception[J]. Journal of Dairy Science,2003,86(6):2012-2021.
[45] López-Gatius F,Santolaria P,Martino A,et al.The effects of GnRH treatment at the time of AI and 12 days later on reproductive performance of high producing dairy cows during the warm season in northeastern Spain[J]. Theriogenology,2006,65(4):820-830.
[46] Willard S,Gandy S,Bowers S,et al.The effects of GnRH administration postinsemination on serum concentrations of progesterone and pregnancy rates in dairy cattle exposed to mild summer heat stress[J]. Theriogenology,2003,59(8):1799-1810.
[47] Mendonça L G D,Mantelo F M,Stevenson J S. Fertility of lactating dairy cows treated with gonadotropin-releasing hormone at AI,5 days after AI,or both,during summer heat stress[J]. Theriogenology,2017,91:9-16.
[48] Vasconcelos J L M,Sá Filho O G,Justolin P L T,et al. Effects of postbreeding gonadotropin treatments on conception rates of lactating dairy cows subjected to timed artificial insemination or embryo transfer in a tropical environment[J]. Journal of Dairy Science,2011,94(1):223-234.
[49] Franco M,Thompson P M,Brad A M,et al.Effectiveness of administration of gonadotropin-releasing hormone at Days 11,14 or 15 after anticipated ovulation for increasing fertility of lactating dairy cows and non-lactating heifers[J]. Theriogenology,2006,66(4):945-954.
[50] Wolfenson D,Kaim M,Rosenberg M.Conception rate of cows supplemented with progesterone post-insemination in the summer[J]. Journal of Animal Science,1994(72):280.
[51] Friedman E,Roth Z,Voet H,et al.Progesterone supplementation postinsemination improves fertility of cooled dairy cows during the summer[J]. Journal of Dairy Science,2012,95(6):3092-3099.
[1] FAN Deyu, GUO Yongqing. Research Progress on the Application of Chromium in Alleviating Heat Stress in Ruminants [J]. China Dairy, 2026, 0(6): 3-9.
[2] ZHANG Wenxue. Research Progress on Precision Regulation of Nutritional Immunity in Dairy Cows Driven by Multi-omics Technologies [J]. China Dairy, 2026, 0(6): 49-55.
[3] Aihemati Maimaiti. Impact of Heat Stress on Reproductive Performance in Dairy Cows and Integrated Mitigation Strategies [J]. China Dairy, 2026, 0(6): 57-64.
[4] GUO Zhijian. Application of Buserelin in the Reproductive Management of Dairy Cows under Heat Stress [J]. China Dairy, 2026, 0(6): 65-74.
[5] GAO Jing. Evaluation of in Vitro Bacteriostatic Activity and Therapeutic Effect of Traditional Chinese Medicine Compound Preparation on Major Pathogens of Dairy Cow Mastitis [J]. China Dairy, 2026, 0(6): 106-110.
[6] LIU Zhaolei. Evaluation of the Application Effect of Probiotic Preparations in Reducing the Incidence of Mastitis in Dairy Cows [J]. China Dairy, 2026, 0(6): 111-116.
[7] ZHANG Yongfang. Comparative Study on the Therapeutic Effects of Traditional Chinese Veterinary Compound and Western Medicine in Dairy Cows with Retained Placenta [J]. China Dairy, 2026, 0(5): 36-40.
[8] WANG Mengmeng, ZHAO Yongfeng, WANG Yaowu, YANG Xu, HAN Meng, TIAN Yuan, WANG Jing, WANG Yudong. Calcium Supplementation Strategies for Postpartum Hypocalcemia in Dairy Cows Based on Precision Nutrition and the Application of Bovikalc [J]. China Dairy, 2026, 0(5): 55-62.
[9] ZHAO Wendi. Research on the Optimization of Bright Dairy's Compensation Incentive Mechanism [J]. China Dairy, 2026, 0(4): 8-13.
[10] WANG Zilong, QIN Shigang. The Effect of Adding Methionine Dipeptides to Feed on the Milk Production Performance of Dairy Cows [J]. China Dairy, 2026, 0(4): 28-32.
[11] LUO Dong, TAN Kai, WANG Tingshuai, GONG Feifei. The Impact of Different Corn Particle Sizes on Lactating Dairy Cow Performance [J]. China Dairy, 2026, 0(3): 40-46.
[12] TIAN Baojun. Effects of Compound Fermented Traditional Chinese Medicine Feed on Production Performance,Serum Biochemical Indicators and Inflammatory Factors of Heat-stressed Dairy Cows [J]. China Dairy, 2026, 0(3): 47-53.
[13] SUN Yun'e. Occurrence and Control Strategy of Hypocalcemia in Perinatal Cows [J]. China Dairy, 2026, 0(3): 54-61.
[14] LI Jiqing. Effects of Probiotic-fermented Feed on Intestinal Microflora,Serum Stress Factors, and Milk Performance in Heat-stressed Dairy Cows [J]. China Dairy, 2026, 0(2): 23-28.
[15] YANG Shengnan, DUAN Xiaoxiao, LIU Shuqing, LIU Xin, QU Hongying, LI Yan. Study on the in vitro Synergistic Antibacterial Effect of the Combination of Traditional Chinese Medicine Compound and Cephalosporin Antibiotics on Multi-drug Resistant Staphylococcus aureus in Bovine Mastitis [J]. China Dairy, 2026, 0(2): 29-35.
Viewed
Full text


Abstract

Cited

  Shared   
  Discussed   
No Suggested Reading articles found!