论文部分内容阅读
为发展毛皮工业 ,新西兰 19世纪中叶从澳大利亚引入刷尾负鼠 (Trichosurusvulpecula) ,后成为新西兰一大害兽。刷尾负鼠不仅因破坏当地植被、捕食鸟蛋等而严重影响了新西兰的生物多样性 ,而且因其传播结核病菌对当地畜牧业造成了很大损失。新西兰每年花费巨额资金来控制这一害兽。虽然刷尾负鼠在一些孤立的岛屿和重点自然保护区已完全被消灭或得到有效的控制 ,但在新西兰大部分地区其分布却还在扩展 ,依然威胁着新西兰的生物多样性和农牧业生产。传统的控制方法包括兽夹捕杀、射杀和药物灭杀 ,其效果不佳的主要原因是 :1)受资金的限制 ;2 )小面积控制后因为种群密度减小 ,负鼠的生育率、存活率随之增高。加上新个体从周围迁入 ,种群数量迅速恢复。生物防治特别是免疫绝育法被认为是经济、人道及有效的方法。新的研究结果证明刷尾负鼠具有一雄多雌的繁殖方式 ,而且在雌兽被绝育后 ,种群中雄兽与雌兽之比率反而增高。因此雌兽绝育可能不会降低雌雄负鼠之间的接触频率。这些研究结果表明免疫绝育控制刷尾负鼠是很有前景的。
To develop the fur industry, New Zealand introduced the Trichosurus vulgaris from Australia in the mid-19th century and later became a major animal in New Zealand. The brush possum not only severely affected the biodiversity of New Zealand by destroying local vegetation and feeding on eggs, but also caused great losses to local livestock husbandry because of its spread of tuberculosis bacteria. New Zealand spends huge sums of money each year to control this pest. Although the brush-crested possum has been completely eliminated or effectively controlled in some isolated islands and key nature reserves, its distribution is still expanding in most parts of New Zealand and still threatens New Zealand’s biodiversity and agriculture and animal husbandry produce. The traditional control methods include bee-killing, shooting and drug-killing. The main reasons for their poor performance are as follows: 1) limited by the funds; 2) after small area control, because the population density is reduced, the fertility rate of the opossum, Survival rate will be higher. With new individuals moving in from around, the population recovered quickly. Biological control, especially immunization, is considered as an economical, humane and effective method. The results of the new study show that brushing possums have the reproductive pattern of male and female, and the ratio of male to female in the population increases instead after the female is sterilized. Female insemination may therefore not reduce the frequency of contact between the male and female possums. These findings suggest that immunosuppression is very promising for controlling brushing possums.