Optimization of water supply system with constant temperature in winter based on effect of water temperature on growth performance of beef cattle

Abstract: In order to relieve the cold stress of beef cattle and increase the beef production efficiency during winter in Northwest China, a comparison study was conducted to evaluate the performance and the economic viability of the constant temperature water supply system. Simmental crossbreed cattle was used as experiment animal, and the temperature inside the constant temperature water supply system, the drinking behavior and the physiology of the beef cattle, and the growing performance were determined. This experiment was conducted in 2 barns with pitched roof in Zhangye area of Gansu Province, China. In the study, the control group was fed with cold water once a day, and cows in the treatment group were constantly supplied with warm water and divided into 4 groups according to the degree of thermal insulation means. The constant temperature water supply system used in this experiment contains heating tank (with heating rods and float inside), temperature controller, 29 drinking cups (2 kinds, insulation drinking cups with insulation material interlayer and single-layer drinking cups without insulation), and water supply and return pipe (2 kinds, insulation pipes with insulation material interlayer and single-layer pipes without insulation). The float inside the tank can control water level in the tank and drinking cups. Temperature probe connected with temperature controllers can set the upper and lower limit of temperature. When the temperature in the tank is higher than the upper limit of temperature, the heating rod stops heating. And heating rod starts heating when the temperature is below the lower limit of temperature. During this experiment period, the time interval of water drinking was recorded by using the behavior monitor and the water temperature was measured as well. Record the behavior of every single cattle, and count the drinking time every 10 minutes to study the relationship between drink behavior and water temperature. The body surface temperature nearby rumen was measured for those cattle which were monitored. Meanwhile, the thermal insulations of these 4 groups were compared, and the relationship between the water temperature and the drinking behavior and the daily body weight gain of the beef cattle was explored. The results showed that the constant temperature water supply system supplied with warm water at 17.69℃ using the thermostatic drinking system, and the daily body weight gain by drinking warm water was 1.53 kg/d per cattle, which was significantly increased by 0.36 kg/d per cattle compared to cattle from the control barn (P<0.01). In the treatment barn, cattle drunk more and had higher body weight gain in the group with warm water at 16-18℃ (the daily body weight gain was 1.69±0.44 kg/d per cattle). The rumen surface temperature of the treatment group after drinking water was 3.29℃ higher than the control group (P<0.01). Through calculation, the economic performance of 4 groups (A, B, C and D) with the warm water supply system and the control group could obtain profits of 3732.5, 3109.9, 2890.1, 2875.4 and 2632.5 yuan on average, respectively, for every cow in one winter. Thus, Group A showed the highest profit. In conclusion, the study shows that the constant temperature water supply system can effectively relieve the cold stress and thus significantly improve the production performance of beef cattle, and it has the technical and economic feasibility.