Abstract: The aim of this study was to analyze the correlation between environmental parameter of rolling shed and lactation performance and behavior of dairy cows. A cowshed was used, which was equipped with roller shutter on both south and north walls. The 200 healthy multiparous Holstein lactating cows (3 to 4 parity, (650±100) kg body weight, 5 to 6 years old) were used in this study, and indoor ambient parameters of rolling shed were detected for a natural year, as well as lactation performance and cow behavior. The ambient parameters included thermal para-meters (temperature (Ta), relative humidity (RH), wind speed (Ws)), airborne microorganisms (bacteria and fungi), dust (PM_2.5 and PM₁₀), harmful gases (carbon dioxide (CO₂) and ammonia (NH₃)). The study was performed to investigate correlation of ambient parameters of rolling shed with lactation or behavior of dairy cow. The results showed that:1) All ambient parameters demonstrated the seasonal variation. Among seasons, the content of fungus (1 049.91 cfu·m^-3) and two kinds of dusts(PM_2.5=17.86 μg·m^-3; PM₁₀=193.07 μg·m^-3) were the highest in summer, and bacteria content was the highest in autumn (1.11×10⁴cfu·m^-3), while CO₂ concentration(1 302.85 mg·m^-3) and NH₃ concentration (2.51 mg·m^-3) exhibited the highest value in winter. 2) The correlation between ambient parameters and lactation performance demonstrated the seasonal variation. Particularly in summer and winter, summer Ta or RH was linearly negatively and significantly correlated (P<0.05) with milk yield, and Ws was linearly positively and signifi-cantly correlated with milk yield (P<0.01). In winter, Ta or RH demonstrated a great influence on milk yield, and milk yield increased with the increasing temperature, showing a linear positive and significant correlation (P<0.01), while the correlation of RH with milk yield showed an opposite law. 3) Correlation between ambient parameters and behavioral parameters showed seasonality. In spring, Ta and CO₂ were key parameters affecting cow behavior. Ta was linearly positively and significantly correlated with feeding time or lying time (P<0.05), while CO₂ concentration was linearly negatively and significantly correlated with feeding time or lying time (P<0.05). In summer, Ta, RH and Ws affected mainly cow behavior. With increasing Ta, feeding frequency linearly and significantly decreased (P<0.05), drinking frequency, single drinking time and single standing time linearly and significantly increased (P<0.05, P<0.01). Also, the greater the Ws, the longer the feeding time (P<0.05). In addition, Ta and RH played important roles also in behavior in winter, Ta was linearly positively and significantly correlated with lying time (P<0.01). The correlation between ambient parameters and milk performance or behavior parameters of dairy cows showed seasonal regularity. There was a stronger correlation between environmental parameters and milking performance in both summer and winter, and Ta and RH were key parameters affecting cow behavior.

Key words: ambient parameters, lactation performance, behavior, harmful gas