开放式牛舍舍内喷雾和屋面喷淋通风降温改善肉牛生产性能

    Cooling by interior spraying ventilation and roofing sprinkling ventilation on open beef cattle barn improving production performance of beef cattle

    • 摘要: 为缓解南方夏季高温高湿热应激对肉牛生产性能的影响,探讨不同降温方式对肉牛的降温效果。以江西省地方品种锦江黄牛为试验对象,试验分为3组,每组8头牛,试验1、2和3组分别为舍内通风组、舍内喷雾通风组和屋面喷淋通风组,3个组牛的平均体质量分别为(250.38±24.54)、(247.93±24.54)和(250.00±24.02)kg(P>0.05),试验于2014年7—8月进行。分别测定了环境温度、湿度,肉牛直肠温度、呼吸频率和日增质量等,结果表明:屋面喷淋运行期间(10:00—18:00),与1组相比,3组舍内距屋顶0、1、2和3 m处温度分别降低4.79(P<0.01)、2.13、1.37 和1.42 ℃;湿度分别增加9.66%(P<0.01)、6.76%(P<0.01)、2.66%和1.80%;在14:00时,距离地面高度1.5和0.5 m分别降低1.20(P<0.05)和1.07 ℃;呼吸频率降低12次/min(P<0.01);直肠温度差异不显著;日增质量提高0.19 kg/d,提高率为26.38%(P<0.05)。喷雾运行期间14:00时,与1组相比,2组肉牛体感温度喷雾前后分别降低0.51 和1.43 ℃(P<0.05),在18:00分别下降0.70 和1.60 ℃(P<0.05);呼吸频率降低13次/min(P<0.01);直肠温度差异不显著;日增质量提高0.08 kg/d,提高率为11.11%。从以上结果可以看出,喷雾通风和屋面喷淋通风均可以一定程度缓解肉牛的热应激。

       

      Abstract: In order to relieve the summer heat stress in South on production performance of beef cattle and investigate the effects of different environmental regulation forms, 24 Jinjiang beet cattle were randomly divided into 3 groups, and each group had 8 cattle. Environmental regulation forms of Group 1, Group 2 and Groups 3 were interior ventilation, interior spray ventilation and roof sprinkling ventilation, respectively. The average weight of 3 groups was(250.38±24.54), (247.93±24.54) and(250.00±24.02) kg(P>0.05), respectively. Experiment was conducted in July and August, 2014. Environment temperature, relative humidity, cattle rectal temperature, breathing rate and daily weight gain were measured. Economic benefits of interior spray ventilation and roof sprinkling ventilation were analyzed. The results showed that compared with Group 1, during running time(between10:00 and 18:00) for the roof sprinkling ventilation, the temperature at 0, 1, 2 and 3 m under the roof decreased by 4.79(P<0.01), 2.13(P<0.01), 1.37 and 1.42 ℃, respectively; the relative humidity increased by 9.66%(P<0.01), 6.76%(P<0.01), 2.66% and 1.80%; respectively; the temperature of 1.5 and 0.5 m from the ground decreased by 1.2(P<0.05) and 1.07 ℃, respectively at 14:00; the dry-bulb temperature and relative humidity from the ground were(33.61±1.55) ℃ and 61.23%±4.03%, respectively, while those of Group 1 were(35.28±1.62) ℃ and 56.43%±3.62%, respectively. Compared with Group 1, the temperature of Group 3 decreased by 1.67 ℃(P<0.01), but the relative humidity increased by 4.80%(P<0.05). The dry-bulb temperature and relative humidity of Group 2 before spray ventilation were(34.58±1.73) ℃ and 57.34%±4.25%. The temperature and relative humidity of Group 2 after spray ventilation were(32.03±1.85) ℃ and 67.65%±5.65%. Compared with Group 1, the temperature of Group 2 before and after spray decreased by 0.70 and 3.25 ℃(P<0.01), respectively, but the relative humidity increased by 0.91%(P>0.05) and 11.22%(P<0.01), respectively. At 14:00 and 18:00, the temperature-humidity-velocity index(THVI) of Group 2 before and after the spray decreased by 0.51 and 0.70 ℃(P<0.05), respectively; meanwhile the THVI of Group 3 before and after the spray decreased by 0.99(P<0.05) and 0.85℃(P<0.05), respectively. The breathing rate of Group 2 and 3 decreased by 13 and 12 times/min(P<0.05), respectively. The rectal temperature of beef cattle in all groups was within normal range. Compared with Group 1, the daily weight gain of Group 2 and 3 increased by 11.11% and 26.36%(P<0.05), and the input-output ratio improved by 14.01% and 14.65%, respectively. These results suggest that the heat stress of beef cattle in South can be relieved by interior spray ventilation and roof sprinkling ventilation in some way. Economic benefits of Group 2 and 3 are improved. Moreover, the effect of roof sprinkling ventilation is prior to that of interior spray ventilation.

       

    /

    返回文章
    返回