Classical BC: NonArthropods Pages 138141 - PowerPoint PPT Presentation

Title: Classical BC: NonArthropods Pages 138141


1
Classical BC Non-Arthropods (Pages 138-141)
Mollusks Snails (Pages 138 139) Snails
include agricultural pests and intermediate hosts
for some flukes that parasitize humans and
livestock. Agricultural Pests The garden (and
edible) snail, Helix aspera, can be a
pest. Predaceous snail, Rumina decollata, can
give good control,predaceous beetles failed to
give control. Giant African land snail, Achatina
fulica, controlled by predaceous snail Euglandia
rosea. E. rosea has also attacked native snails
in Tahiti.
2
Classical BC Non-Arthropods (Pages 138-141)
Mollusks Snails (Pages 138 139) Medical and
Veterinary Pests Biomphalaria glabrata, major
host of liver fluke, Schistosoma Mansoni, causes
schistosomiasis/bilharzia Several snail genera
used to compete for food (plants)
consume Biomphalaria eggs Control variable, best
in small, isolated ponds Biomphalaria
glabrata
Schistosoma mansoni,infective stage
3
Classical BC Non-Arthropods (Pages 138-141)
Mollusks Snails (Pages 138 139) Medical and
Veterinary Pests Schistosoma haematobium, giant
liver fluke of cattle, introduced from Central
America to Hawaii. Imported snail predator
flies, Sepedon spp. (Diptera Sciomyzidae), to
control the snail hosts, Bulinus
spp. Slaughterhouse records indicate fluke
incidence declined.
4
Classical BC Non-Arthropods (Pages 138-141)
Vertebrates (Pages 139-141) A few recent bad
ideas, e. g. greater kiskadee in Trinidad, but a
few successes Domestic cats on islands have
been infected with feline panleucopaenia virus.
Reduced cat populations. Mice in Australia have
been inoculated with a liver nematode, Capillaria
hepatica., Recent, results unclear. Feral
goats on islands infected with protozoan
Trichomonas foetidus, induces abortions/reduces
fecundity. Reducing goat populations in some
places.
5
Classical BC Non-Arthropods (Pages 138-141)
Vertebrates (Pages 139-141) Rabbits in
Australia, the famous example European rabbit
introduced by early immigrants 1950 Reached
average density of 191 per hectare
maximum density of 367 per hectare Myxoma virus
introduced from North America specific to
Leporidae, no leporids native to Australia
antigenically stable Virus is transmitted by
blood-feeding arthropods.
6
Classical BC Non-Arthropods (Pages 138-141)
Vertebrates (Pages 139-141) Rabbits in
Australia, the famous example Myxoma virus gave
good control Predators then became more
effective 1970 rabbit densities 1 of 1950
levels (99 control) Rabbits began to evolve
resistance to myxoma virus. In the 1980s RCD
virus was being tested on an island andwas
accidentally introduced to mainland Australia.
It has enhanced control of the rabbits.
7
Classical BC Non-Arthropods (Pages 138-141)
Vertebrates (Pages 139-141) Rabbits in New
Zealand, a notorious example Rabbit densities in
New Zealand were 20 per hectare, blamed for
damaging rangeland, but overgrazing may have
been the dominant factor (govt. paid ranchers
per sheep, big political battles
ensued). Neither Myxoma or RCD virus was
introduced to New Zealand.Ranchers group went
to meeting in Australia, somebody apparently
smuggled the RCD virus into New Zealand.