恒温饮水系统促进开放舍冬季断奶仔兔生长

Promoting the growth of weaned rabbits in open shed in winter using thermostatic drinking system

为研究冬季饮用温水对断奶仔兔健康状况和生长性能的影响,该研究选择180只47日龄断奶仔兔(初始体质量(1.2±0.1)kg)随机分为2组,温水组通过在冬季塑料薄膜封闭的开放舍饮水管道上安装伴热线恒温加热系统,为仔兔提供35.5℃的温水,对照为无加热系统的冷水组,水温为5.8℃。试验期48 d。结果表明:1)在舍内平均气温8.9℃情况下,与冷水组相比,温水组家兔在47~58和47~94日龄范围的平均日增质量分别显著提高15.11和1.94 kg(P<0.05)。2)饮用温水显著降低47~58日龄范围家兔平均料质量比(18.2%)及47~94日龄范围家兔的腹泻发生率(25.6%)(P<0.05)。显著下调了70日龄家兔空肠中甲状腺激素受体α和β(THRα和β)的表达量(P<0.05)。3)随着日龄的增加,饮用温水显著提高了82日龄家兔血清中免疫球蛋白A(Immunoglobulin A,IgA)和总蛋白(Total protein,TP)含量(P<0.05),也显著提高了82日龄家兔盲肠菌属Roseburia的丰度,是58日龄的6.9倍(P<0.05)。因此,冬季开放舍安装恒温饮水系统可通过提高机体免疫和肠道消化吸收能力,进而促进仔兔生长,改善健康状况。

Cold stress of livestock easily occurs in open sheds of cold areas during winter, due mainly to the relatively low thermal insulation under the low temperature conditions. As such, cold drinking water can further deteriorate the health and growth of young livestock. The objective of this study was to investigate the effect of drinking warm water in winter on the health and growth performance of weaned rabbits. A total of 180 weaned rabbits(47 days of age) with similar body weight(initial body weight 1.2±0.1 kg) were randomly assigned to two groups, either warm water(WW) or cold water(CW)(90 rabbits in each group). An electrical heating wire was also used to heat the warm water, where the water pipe was covered with insulated foam coating. A thermostatic controller was selected to remain at a constant temperature(35.5 ± 1.1 ℃) during the experiment. The cold water was prepared at(5.8 ± 2.3)℃ without heating. A 48-day test was carried out to measure various indicators. The results showed that: 1) The indoor average air temperature was(8.9±3.2)℃ during the experiment. The average daily weight gain of rabbits in warm water group was significantly higher than that in cold water group during 47-58 days and 47-94 days, respectively, by 15.11 kg/d and 1.94 kg/d(P<0.05). 2) The feed-weight ratio of rabbits was significantly lower in the warm water group than that in the cold water group during 47~58 days(18.2%)(P < 0.05). But there was no significant difference during the rest. In addition, the risk of diarrhea in rabbits drinking warm water was significantly reduced by 25.6% during 47~94 days(P < 0.05), compared with the cold water group. The expressions of thyroid hormone receptor α and β(THR α and β) in jejunum were significantly down-regulated on 70 days in rabbits drinking warm water(P < 0.05). 3) The contents of immunoglobulin A(IgA) and total protein(TP) in serum increased significantly for the rabbits drinking warm water, with the increase of age, especially on 82 days(P < 0.05). Moreover, the abundance of Roseburia increased in the cecum of rabbits on 82 days in the warm water group, relating to nutrient digestion and absorption,indicating 6.9 times higher than that of 58-day old rabbits(P < 0.05). Consequently, the constant temperature drinking system in the open sheds in winter can be expected to improve the immunity, intestinal digestion, and absorption capacity, thereby promoting the growth and health of weaned rabbits. The finding can provide theoretical support to improve the survival rate and production efficiency of weaned rabbits in open houses in cold areas.