Most ReadThis paper reviewed the intrinsic mechanisms through which heat stress affected reproductive performance in dairy cows, scientific assessment methods, and integrated mitigation strategies.It provided an in-depth analysis of the physiological and molecular mechanisms by which heat stress impairs fertility through multiple pathways, including inducing oxidative stress, disrupting endocrine homeostasis, impairing oocyte quality and embryonic development, and interfering with epigenetic programning.The paper explored heat stress assessment systems based on the temperature-humidity index, physiological indicators (such as rectal temperature and respiratory rate) , and behavioral changes, and analyzed their associations with key reproductive traits such as conception rate and the interval to first postpartum ovulation.It comprehensively reviewed current research progress and the potential of strategies to mitigate the negative effects of heat stress, including genetic selection, precise nutritional regulation, environmental improvements, and emerging biotechnologies, offering theoretical foundations and practical guidance for dairy farms to establish efficient heat stress response systems and enhance reproductive efficiency.
To investigate the preventive and therapeutic effects of a self-formulated traditional Chinese medicine compound on bovine mastitis.
The in vitro antibacterial activity of this compound against the main pathogens causing bovine mastitis was determined, and its clinical efficacy was evaluated.
The minimum inhibitory concentration (MIC) of the traditional Chinese medicine compound against Staphylococcus aureus and Streptococcus agalactiae was 31.25 mg/mL, and the MIC against Escherichia coli was 62.5 mg/mL, indicating moderate sensitivity. The results of different drug interventions showed that the high-dose group of the traditional Chinese medicine compound had the highest clinical efficacy and cure rate, reaching 100% and 83.33%, respectively; followed by the antibiotic group, with an efficacy rate of 83.33% and a cure rate of 66.67%; the medium-dose group of the traditional Chinese medicine compound had an efficacy rate of 66.67%; and the low-dose group of the traditional Chinese medicine compound had the worst effect, with an efficacy rate of 50% and a cure rate of 16.67%. After medication, the somatic cell count (SCC) of milk in all groups decreased significantly (P< 0.05) ; among them, the SCC of milk in the medium-dose group, high-dose group, and antibiotic group were all below 200000 cells/mL, namely 19.35±0.32, 11.32±0.44, and 14.52±0.21×104 cells/mL, respectively. Compared with the blank control group, the average daily feed intake of dairy cows in each medication group increased significantly (P<0.05) ; the milk yield of the medium and high dose groups of the traditional Chinese medicine compound increased significantly (P<0.05) , and the milk-to-feed ratio showed an upward trend (P>0.05) .
This traditional Chinese medicine compound can effectively inhibit the proliferation of Staphylococcus aureus, Streptococcus agalactiae, and Escherichia coii, and has a good therapeutic effect on mastitis in dairy cows, which can significantly reduce the somatic cell count of milk; the high-dose compound is more effective than conventional antibiotics, and can also increase the feed intake and milk yield of sick dairy cows, and improve their health status.
Heat stress caused by high temperatures in summer is a key challenge restricting the profitability of dairy farming. It not only reduces milk yield but also significantly impairs the reproductive performance of dairy cows. This paper systematically reviewed the mechanisms by which heat stress damages the physiological functions, endocrine homeostasis, and reproductive performance of dairy cows, with a focus on analyzing the negative effects of high-temperature enviromments on estrus expression, follicular development, early embryonic survival, and pregnancy success rates. Combined with field trial data, this paper elaborates on the application effects of the novel gonadotropin-releasing hormone (GnRH) analogue buserelin in scenarios such as fixed-time artificial insemination synchronization, reducing early embryonic mortality, and treating ovarian cysts. The study confirmed that buserelin can significantly alleviate heat stress-induced reproductive damage, improve summer conception rates, and enhance overall reproductive efficiency in dairy cows by regulating the endocrine status, increasing progesterone concentrations, and improving oocyte quality and the uterine environment. This provided a scientifically based practical solution for reproductive management in large-scale farms during summer.
To study the effects of different storage conditions on the microbial and physicochemical properties of pasteurized milk.
Pasteurized milk was stored at 2, 7, 10, 15, 25 and 35 ℃ for 0~72 h respectively, and the changes in microbial count, pH value and acidity were measured regularly.
With the extension of storage time and the increase of temperature, the total bacterial count, the number of lactic acid bacteria, and the number of coliform bacteria in pasteurized milk all increased significantly (P<0.05). In pasteurized milk stored at 7 ℃, the microbial growth was slow, and the total bacterial count remained within the safe range at 72 h; when stored at 15 ℃, the microbial growth rate accelerated, and the total bacterial count exceeded the national standard limit after 36 h; when stored at 25 ℃ and 35 ℃, the microorganisms proliferated rapidly, far exceeding the national standard limit. The pH value of pasteurized milk gradually decreased with the extension of storage time and the increase of temperature, while the acidity gradually increased. The changing trends of both were closely related to the growth of microorganisms.
Refrigeration at 7 ℃ could effectively inhibit the growth of microorganisms in pasteurized milk and extend its shelf-life. When storing pasteurized milk at room temperature, it should be consumed as soon as possible to avoid quality deterioration caused by excessive microbial growth.
To investigate the effects of estrus synchronization and artificial insemination (AI) technology on the conception rate of dairy goats, providing technical support for improving breeding efficiency and standardized development of the industry.
A total of 3 805 breeding does from 37 dairy goat farms in Longxian County, Shaanxi Province, were studied.Two breeding methods were compared: ①natural estrus+AI; and②estrus synchronization (using intravaginal sponges impregnated with fluorogestone acetate combined with PMSG and PG hormone treatments) +AI.The conception rate was determined via ultrasound pregnancy testing, and the effects of farming methods, insemination sites, breeding timing, and other factors were analyzed.
The average conception rate in the estrus synchronization+AI group was 71.56%, significantly higher than that in the natural estrus group (68.56%).The optimal combination was semi-grazing and semi-penned farming (73.10%), cervical insemination (74.39%), and breeding in August (75.49%).
Estrus synchronization technology can significantly improve the conception rate of dairy goats, with its effectiveness influenced by farming models, operational protocols, and seasonal factors.Tailored implementation plans are recommended to promote high-quality industry development.
With the rapid development of economy and technology, China's dairy industry has achieved high-quality development driven by industrial upgrading and technological innovation. The dairy product quality and safety supervision system has been continuously improved, relevant laws and regulations have become increasingly sound, and supervision capacity and efficiency have been significantly enhanced, laying a solid foundation for the healthy development of the industry and the protection of public health. At present, the dairy industry maintains a good momentum of large-scale and diversified development, but the application of science and technology and the evolution of industrial forms have also brought a few new regulatory challenges. In addition, there is an inherent lag in legal practice, and the supervision mechanism still has room for refinement and optimization. Improving the dairy product quality and safety supervision mechanism is of great significance for consolidating supervision results, improving governance levels, and promoting the sustainable development of the industry. Based on the perspective of multi-center governance, this paper analyzed the current situation of dairy product quality and safety supervision in China, focused on the optimization space in terms of the definition of departmental responsibilities, information sharing mechanisms, market access and recall systems, and the participation of industry associations, and proposes systematic and collaborative governance paths combined with typical cases, so as to help build a scientific, efficient and socially co-governed new pattern of dairy product safety supervision.
To evaluate the application effect of probiotic preparations in the health management of dairy cows, this study took lactating cows from a large-scale dairy farm in Yishui County, Shandong Province, as the research subjects.A controlled trial method was used to systematically analyze the effects of probiotic preparations on the incidence of mastitis, milk quality, and milk production performance.
Healthy lactating Holstein cows were randomly divided into a control group and a probiotic group.The control group was fed a basic diet, while the experimental group received the same diet supplemented with a compound probiotic preparation.The trial lasted for a continuous feeding period.By recording the incidence of mastitis and measuring milk quality indicators (somatic cell count, milk fat percentage, milk protein percentage, and lactose percentage) as well as milk production performance indicators (daily milk yield and milk production stability), a comprehensive evaluation of the application effect of the probiotic preparation was conducted.
The results showed that compared with the control group, the incidence of mastitis in the probiotic group was significantly reduced (P<0.05), somatic cell count in milk decreased significantly (P<0.01), and both milk fat and protein percentages increased to varying degrees (P<0.05), while lactose percentage showed no significant difference (P>0.05). The probiotic group showed a higher average daily milk yield than that of the control group, though the difference was not significant (P>0.05), and exhibited better production stability; however, milk production stability was significantly better than that of the control group.Additionally, the probiotic group exhibited a lower incidence of subclinical mastitis compared to the control group, with a corresponding decrease in the average subclinical mastitis score, suggesting a reduced risk of subclinical mastitis.Regarding milk conductivity, the probiotic group demonstrated lower conductivity levels than the control group, indicating that probiotic preparations can alleviate the inflammatory burden on mammary glands and improve overall mammary gland health.
In conclusion, probiotic preparations can reduce the risk of mastitis by improving dairy cow health and reducing mammary gland inflammation, enhance milk quality, and increase lactation stability, demonstrating good potential for practical application and promotion.
Heat stress poses a significant challenge to the ruminant livestock industry under the context of global warming, severely impacting animal production performance, immune function, and reproductive efficiency. Chromium, as an essential trace element for animals, plays a key role in regulating glucose and lipid metabolism, enhancing antioxidant capacity, and maintaining immune function. This review summarized the detrimental effects of heat stress on ruminants and its underlying mechanisms, and introduced the sources, types, and application effects of chromium under heat stress conditions. It focused on the ameliorative effects of chromium supplementation on the lactation performance, growth performance, and reproductive performance of ruminants. Furthermore, the review explored the mechanisms of action, including enhancing insulin sensitivity, regulating glucose metabolism, improving antioxidant capacity, boosting immune function, and modulating the rumen microbiota. This review also analyzed existing research limitations, such as insufficient comparability among different chromium sources and the lack of standardized dosage, and proposed future research directions, aiming to provide a theoretical basis and practical reference for alleviating heat stress in ruminants.
To establish an ion chromatography method for the determination of xylitol, erythritol, sorbitol and maltitol in infant formula.
Dionex CarboPacTM MA1 sugar column guard column (4 mm×50 mm) and Dionex CarboPacTM MA1 sugar analysis column (4 mm×250 mm) were used as chromatographic columns, 480mmol/L sodium hydroxide eluent was used for isocratic elution, the flow rate was 0.45mL/min, the injection volume was 10μL, the column temperature was 30℃, and the electrochemical detector was detected.
The mass concentration showed a good linear relationship with its peak area in the range of 0.2~20 μg/mL (r2≥0.99969) , the detection limit was between 0.01~0.20 μg/mL, the average recovery rate was 91.8%~99.1%, and the relative standard deviation (RSD) was in the range of 0.9%~2.9%.
This method was simple to operate, had high sensitivity and good stability, and could provide a reference for the quality control of infant formula.
With the increasing health awareness of consumers, the dairy industry is undergoing a profound transformation-moving from the traditional basic nutrition provision to a strategic upgrade that focuses on precision nutrition and specific health functions. This review aimed to systematically elaborate on the key research progress in dairy product innovation driven by the concept of precision nutrition: Firstly, it analyzed the key bioactive components in dairy sources, including bioactive peptides from milk proteins, milk fat globule membranes (MFGM), and analogues of human milk oligosaccharides (HMOs). In view of the common problems of poor stability and low bioavailability of most active substances, this study further focused on the research breakthrough of efficient delivery systems and explored their cutting-edge application in protecting probiotics and encapsulating hydrophobic functional factors. Finally, this review outlined the challenges and future directions in this field, aiming to provide a solid theoretical basis for the development of the next generation of personalized and highly functional dairy products.
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