新增羊只时的羊只类型，各页面导出功能需求，改品种功能的原品种回显需求，完成

src/views/produce/manage_sheep/changeVariety/index.vue

@@ -157,7 +157,13 @@
           </el-button>
         </div>
         <el-form-item label="原品种" prop="varietyOld">
-          <el-input v-model="form.varietyOld" placeholder="页面自动获取展示" disabled />
+          <span v-if="batchSheep.length === 0" class="placeholder-text">请输入耳号后自动获取</span>
+          <div v-else class="variety-old-list">
+            <el-tag v-for="(sheep, idx) in batchSheep" :key="sheep.id" type="warning" effect="plain" size="small"
+              style="margin: 2px 4px 2px 0;">
+              {{ sheep.varietyName || '未知品种' }}
+            </el-tag>
+          </div>
         </el-form-item>
         <el-form-item label="新品种" prop="varietyNew">
           <el-select v-model="form.varietyNew" placeholder="请选择新品种" clearable filterable :disabled="!isAdd">
@@ -437,12 +443,18 @@ function handleDelete(row) {
 
 /** 导出按钮操作 */
 function handleExport() {
-  proxy.download('changeVariety/changeVariety/export', {
-    ...queryParams.value
-  }, `changeVariety_${new Date().getTime()}.xlsx`)
+  queryParams.value.ids = ids.value;
+  
+  try {
+    proxy.download('changeVariety/changeVariety/export', 
+      { ...queryParams.value }, 
+      `改品种记录_${Date.now()}.xlsx`
+    );
+  } finally {
+    queryParams.value.ids = null;
+  }
 }
 
-
 //加载羊舍数据
 const sheepfoldOptions = ref([])
 function getSheepfoldOptions() {
@@ -589,4 +601,34 @@ onMounted(() => {
   flex-wrap: wrap;
   align-items: center;
 }
+
+.variety-old-list {
+  min-height: 32px;
+  /* 与el-input高度一致 */
+  max-height: 150px;
+  overflow-y: auto;
+  padding: 4px 8px;
+  background-color: #f5f7fa;
+  border: 1px solid #dcdfe6;
+  border-radius: 4px;
+  display: flex;
+  flex-wrap: wrap;
+  align-items: center;
+  box-sizing: border-box;
+    width: 100%;
+}
+
+.placeholder-text {
+  display: block;
+  min-height: 32px;
+  line-height: 32px;
+  padding: 0 8px;
+  background-color: #f5f7fa;
+  border: 1px solid #dcdfe6;
+  border-radius: 4px;
+  color: #c0c4cc;
+  font-size: 14px;
+  box-sizing: border-box;
+    width: 100%;
+}
 </style>