PhD

Studies on the incidence of nematode infections in 340
domestic ducks indicated that 67.94% of birds harboured
one or more species of the following nematodes viz.,
Amidostomum
globocaudata
skrjabini , capillaria contorta, capillaria
,
Echinuria
uncinate,
Epomidiostum
uncinatum, Eustrongylides papilosus, Strongyloides avium
and tetramers antis. The rate of infection was highest in
the case of Epomidiostomum uncinatum (41.86% ) and
lowest in the case of strongyloides avium (0.59%).
The
lifecycles of Echinuria uncinata and Tetramers anatis were
worked out in detail. It was established that Tetramers
anatis was distinct from Tetramers Fissispina.
The
complete details of the morphology of juveniles both within
the intermediate and final hosts were given. The juveniles
of Echinuria uncinata completed the first and second
moultings on the third and fifth day respectively and the
stage juveiles reached infective stage on the seventh day
following infection in Daphnia pulex at a room temperature
ranging from 25 to 30C0.
In ducklings the juveniles
underwent the third and fourth moultings on the third and
seventh day respectively and the eggs of the parasite were
first found in the droppings on the thirty- third day. The
juveniles of Tetramers anatis completed first mopulting on
the third day, the second moulting on the fifth day and the
third stage encysted in fat bodies of the grasshopper,
Spathosternum prasiniferum. The third stage juveniles
attained infective stage on the sixth day following infection.
Within the ducklings, the parasite underwent the third
moulting on the third day.
The fourth moulting in respect of males was seen on the
nineth day and in the case of females on the tenth day. The
prepatent period of the parasite was found to be 24 days.
Development of the juveniles was also noticed in five other
species of grasshoppers viz., Oxya nitidula, Oedaleus
abruptus, Conocephalus maculatus, Ducetia Japonica and
Atractomorpha crenulata. No development of Tetrameres
anatis, beyound the first stage was observed inDaphnia
Pulex and Daphnia Magna on experimental infection.
Anaemic changes with significant reduction in weight gain
and haematological values were observed in experimental
infections of Tetrameres anatis, Amidostomum skrjabini
and Epomidiostomum uncinatum. Histopathological
changes like haemorrahage, desquamation of cells, catarrbal
inflammation and necrosis were seen in experimental
tetramerosis. Ulceration and atrophy were also evident in
amidostomiasis and epomidiostomiasis.
The anthelmintic efficacy of 9 drugs against adult worms of
Tetrameres anatis, Amidostomum skrjabini and
Epomidiostomum uncinatum under experimental infections
were determined. The efficacies against tetramerosis,
amidostomiasis and epomidiostomiasis were
79.23%,32.15% and 79.88% with Tetramisole by
drochloride at 50 mg/kg body weight; 70.36%, 52.42% and
50.23% with phenothiazine at 500 mg/kg; 26.85%, 74.8%
and 65.68% with Morantel tartrate at 40mg/kg; 45.70%
67.29% and 57.84% with Parbendazole at 100 mg/kg;
41,0%’63/93% and 43.13% with Thiabendazole at 200
mg/kg; 59.28%,61.06% and 52.66% with
Carbontetrachloride at 2ml/kg; 35.94%, 30,12% and
13.13% with Methyridine at 200 mg/kg; 28.87% 20.17% and
11.32% with Disophenol at 10 mg/kg and 31.02%, 39.04%
and 12.66% with Cashewnut shell oil at 10 g/kg body weight
respeectively. The drug Rametin at 200 mg/kg was found to
be fatal to ducklings.
In a cross infection trial delyed development and lesser
percentage of establishement of Ascaridia galli of fowl origin
were observed in ducklings as compared to chicks.