引起鸡传染性支气管炎发生的因素及防治对策

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鸡传染性支气管炎是由鸡传染性支气管病毒引起的一种急性、高度接触传染性呼吸道疾病.本病的特征是病鸡呼吸困难、打喷嚏和气管发生啰音.在雏鸡还出现流鼻液.产蛋鸡产蛋减少、产畸形蛋、软皮蛋,甚至不产蛋,死亡率较高.
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