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31.
Adult Ascaridia galli and Heterakis gallinae obtained from the fowl (Gallus gallus) were treated in vitro with 10(-2) to 10(-5) M parbendazole and piperazine adipate for 10-60 min at 38 degrees C. Both the compounds at 10(-2) M caused mortality of A. galli and H. gallinae after a maximum of 30 min exposure. The effect of the drugs on the homogenates of the treated worm was investigated. Parbendazole (10(-2) M) inhibited malate oxidation by 68% in A. galli and 62% in H. gallinae. Piperazine adipate (10(-2) M) inhibited malate oxidation by 78% in both parasites. In A. galli oxaloacetate reduction was inhibited by 41 and 26% by 10(-2) M parbendazole and piperazine adipate, respectively; with H. gallinae this inhibition was found to be 39 and 55%, respectively. Aldolase activity in both the parasites was also inhibited by 10(-2) M parbendazole and piperazine adipate. Both compounds caused an inhibition of acid phosphomonoesterase activity, but the activities of lactate dehydrogenase and alkaline phosphomonoesterase were not affected significantly. Parbendazole (10(-2) M) had no significant effect on the cholinesterase activity of these parasites, but piperazine adipate (10(-2) M) caused an inhibition of 96% in A. galli and 93% in H. gallinae. The possible mode of action of the drugs is discussed.  相似文献   
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Colonization of rice fields by the brown planthopper, Nilaparvata lugens (Stål) (Homoptera: Delphacidae), was monitored using yellow pan oil-water traps. In approximately 3 months, 35 788 immigrant macropters (1·0 ♂: 1·2 ♀) were caught in 512 traps installed over a 0·352 ha rice field. The trend of daily trap catches conformed closely to the number of macropters visually counted on rice hills. In sub-plots with a trap crop planted 20 days earlier than the main crop on a quarter of the total crop area, more macropters were recorded on trap-crop than on main-crop rows up to about 75 days after transplanting the main crop. In control sub-plots with one planting, more hoppers arrived on the middle than on the border rows. A blanket spray application of Perthane (0·75 kg a.i./ha) was made on the crop in control sub-plots, whereas only the trap crop was sprayed in trapped sub-plots. The combined yield in each treatment with trap crop was significantly higher than in the control treatment.  相似文献   
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The prevalence of capsular and somatic serotypes were studied among 123 Pasteurella multocida strains isolated from chickens (n = 94), ducks (22), quails (4), turkeys (2) and geese (1) from different geographical regions of India. All strains exhibited similar cultural and morphological characteristics. Ninety-two of the isolates belonged to serotype A:1, the most prevalent serotype, with serotypes A:3, A:1,3, D:3 and F:3 having two isolates each. Only one isolate was positive for serotypes A:4 and D:1. Twenty isolates were untyped. A multiplex capsular PCR assay generated amplicons of sizes 460, 1044, 657 and 854 bp in 106 isolates identified as capsular serotype-A, 15 in serotype D and two in serotype F. Capsular types B and E were not detected in any of the avian isolates studied. The present findings suggest that a multiplex capsular PCR assay may be suitable for the rapid initial identification serotypes P. multocida during epidemiological studies of fowl cholera.  相似文献   
36.
1. The primary antibody response to sheep erythrocytes was determined by haemagglutination test in guinea fowl. The effects of various genetic and non‐genetic factors on immune response to sheep RBCs in guinea fowl were also estimated.

2. The immune response to sheep RBCs was normally distributed in guinea fowl with mean titre at 1.534 ± 0.014.

3. In guinea fowl, effects on titre values of sire and variety (feather colour) were significant whereas sex and sex × variety interaction effects were non‐significant.

4. The estimate of heritability for immune response to sheep RBCs in guinea fowl was 0.35 ±0.17.  相似文献   

37.
Laying WLH pullets were housed individually in cages with floor areas of either 930 cm2 (group 1) or 3700 cm2 (group 2). Half the birds from each group were killed after 35 d confinement and the other half on the 70th d. Balance studies were conducted from 25th to 35th d and from 60th to 70th d.

The more severely confined birds had depressed plasma alkaline phosphatase activity but a raised plasma cholesterol level after 35 d. The alkaline phosphatase activity returned to normal after 70 d but the hypercholesterolaemia persisted. Acid phosphatase activity and plasma protein levels were unaffected by the treatments.

Pullets in the smaller cages laid fewer eggs but egg weight was unaffected.

Neither percentage metabolisable energy nor metabolisable nitrogen of the diet was affected by the severity of confinement, though less dietary nitrogen was retained by either group in the first half of the confinement period.

Severe confinement resulted in higher values of percentage metabolisable calcium and phosphorus by the 35th d but these decreased by the 70th d. In the less severely confined birds these values by the 70th d were higher than those at the 35th d.  相似文献   

38.
The effects of nitrogen and sulphur on the yield and fatty acid composition of mustard ( Brassica juncea L.) oil were studied in a field experiment. Significantly higher grain and oil yields were obtained with N and S application. Applications of nitrogen up to 60 kg ha−1 and sulphur up to 40 kg ha−1 favourably influenced the grain yield. Increasing levels of N decreased the oil content while application of sulphur improved the oil content. The contents of linoleic and linolenic acid were maximum (16.82 and 8.73%, respectively) with 60 kg N along with 40 kg S ha−1. No use of fertilizers led to higher contents of undesirable fatty acids such as palmitic (hypercholesterimic) and erucic (do not have food value) acids.  相似文献   
39.
Two trials were conducted to determine the effects of dietary enrichments with the microalga Parietochloris incisa , rich in arachidonic acid (ARA), on stress resistance in guppies Poecilia reticulata . The microalga was added to commercial diets as a neutral lipid (NL) extract and its fractions or as broken cells. Experimental diets were applied for a period of 14 days. In trial 1, commercial diets were supplemented with NL (containing 25 mg ARA and 0.11 mg β-carotene g−1 feed), its triacylglycerol (TAG) fraction (containing 25 mg ARA g−1 feed and no β-carotene) and the β-carotene fraction (containing 0.11 mg carotenoid g−1 feed and minute amounts of ARA). Neutral lipid-fed fish demonstrated the highest resistance ( P <0.05) to osmotic stress (32-ppt NaCl), followed by fish fed with diets supplemented with TAG and β-carotene alone, which were more resistant than control ( P <0.05). In trial 2, fish fed diets supplemented with higher levels of broken alga (26.1 mg ARA g−1 feed) were more resistant ( P <0.05) to stress as compared with fish fed lower ARA (16.3 mg g g−1) or an unsupplemented control diet. We suggest a dietary supplementation with broken P. incisa cells to enhance stress resistance in guppies before a stressful event.  相似文献   
40.
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