首页
登录
职称英语
The koala, one of Australia’s most treasured creatures, is in trouble? In Qu
The koala, one of Australia’s most treasured creatures, is in trouble? In Qu
游客
2023-12-23
9
管理
问题
The koala, one of Australia’s most treasured creatures, is in trouble? In Queensland, the vast state in Australia’s northeastern corner, surveys suggest that from 2001 to 2008, their numbers dropped as much as 45 percent in urban areas and 15 percent in bush land.
While climate change and habitat loss are affecting koalas and many other Australian animals— from birds and frogs to marsupials like wombats—it is a bacterial infection that is worrying many scientists about the fate of the koala. "Disease is a somewhat silent killer and has the very real potential to finish koala populations in Queensland," said Dr. Amber Gillett, a veterinarian at the Australia Zoo Wildlife Hospital in Beerwah.
The killer is chlamydia, a class of bacteria far better known for causing venereal disease in humans. Recent surveys show that chlamydia has caused symptoms in up to 50 percent of Queensland’s wild koalas, with more probably infected but not showing symptoms. The bacteria— transmitted during birth, through mating and possibly through fighting—come in two strains, neither the same as the human form. One form can jump to other species, but so far there is no evidence that it has spread from koalas to humans or vice versa.
Chlamydia causes a host of symptoms, including eye infections that can lead to blindness, respiratory infections and cysts? The epidemic has been severe in Queensland, where most koalas are infected with koala retrovirus, said Dr. Gillett. This retrovirus is an H. I. V. -like infection that suppresses the immune system and interferes with its ability to fight off chlamydia.
Treating chlamydia in wild koalas is a challenge. Only a small percentage of the animals can be treated successfully and returned to the wild. And infected females often become infertile, so future population growth is affected as well. There is no treatment available for koala retrovirus, but researchers are working to test a vaccine that would help prevent further spreading of chlamydia.
A study published in 2010 in The American Journal of Reproductive Immunology found that this vaccine is safe and effective in healthy female koalas. Further work is being done to test it in koalas that are already infected. Peter Timms, a professor at the Queensland University of Technology who is leading the effort to test the chlamydia vaccine, is hopeful that there will be another trial this year to test it in captive male koalas, followed by wild koalas. If all goes well, plans can be set in motion to distribute the vaccine.
Many experts believe this vaccine would be an important step in helping koalas survive longer, perhaps buying enough time for researchers to solve some of the other problems they face. "In situations where you combine habitat pressure, domestic dog attacks and car hits with severe chlamydial disease, the outcome for koalas is devastating," Dr. Gillett said. [br] The chlamydia vaccine is still in its experimental stage as it has been only tested on______.
选项
A、healthy female koalas
B、infected young koalas
C、captive male koalas
D、wild adult koalas
答案
A
解析
转载请注明原文地址:https://www.tihaiku.com/zcyy/3297342.html
相关试题推荐
WhydoconservationistsinAustraliasupportthepolicyofkillingcats?[br][
WhydoconservationistsinAustraliasupportthepolicyofkillingcats?[br][
WhydoconservationistsinAustraliasupportthepolicyofkillingcats?[br][
WhydoconservationistsinAustraliasupportthepolicyofkillingcats?[br][
TheUniversityintransformation,editedbyAustralianfuturistsSohailInaya
TheUniversityintransformation,editedbyAustralianfuturistsSohailInaya
TheUniversityintransformation,editedbyAustralianfuturistsSohailInaya
[originaltext]TherearethreelevelsofgovernmentinAustralia:firstly,th
[originaltext]W:Derek,howisyourkneetoday?Isitstillgivingyoutrouble?
[originaltext]W:Derek,howisyourkneetoday?Isitstillgivingyoutrouble?
随机试题
CancerandChemicalsLastyear,CaliforniagovernorGeor
A.尿三氯化铁试验 B.DNA分析 C.血游离氨基酸分析 D.尿液有机酸分
柱和墩结构物在进行超声检测时,一般不采用()。A.斜测法 B.直角测法 C
2017年1~2月,我国副省级城市实现软件业务收入3874亿元,同比增长12.9
苯海拉明不具有的性质是A.降低肾素分泌 B.镇静 C.催眠 D.抗胆碱
结构改造后可衍生为克拉霉素的抗生素是A.氯霉素 B.红霉素 C.青霉素 D
网络型组织结构的主要优点是( )A.能够促进组织对顾客的变化做出灵活而快速的反
根据合同法律的理论,下列说法中正确的有()。A.赠与合同是单务合同 B.
如果注册会计师发现前任注册会计师审计的财务报表可能存在重大错报,被审计单位拒绝告
婴儿生理性贫血的时间是出生后( )。A.1个月 B.2~3个月 C.4~6
最新回复
(
0
)