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61.
A marked reduction in the faecal excretion of sporocysts was observed in experimental pups, following the repeated oral administration to them of buffalo cardiac muscle infected with Sarcocystis levinei. Sporocysts excreted from days 9 to 25 post-infection (pi) exhibited a gradual reduction in the quantum. Maximum intensity of excretion of sporocysts was recorded between days 9 and 16 pi, becoming moderate after day 16, light after day 21 and completely absent after day 36. After the subsequent feeding to pups of S. levinei infected buffalo cardiac tissues at 40 day intervals the quantity of sporocysts shed was less, the prepatent period was prolonged and the patent period was considerably shortened. The peak period of excretion varied depending upon the number of exposures of the pups to the infected S. levinei tissues from buffaloes (Bubalus bubalis).  相似文献   
62.
Neurological disease attributed to migration of the rat lungworm ( Angiostrongylus cantonensis ), is described in three captive rufous bettongs ( Aepyprymnus rufescens ). Clinical signs, including ascending paralysis and multifocal neurological deficits, were similar to those seen in other species. Histologically, the severity of meningoencephalomyelitis ranged from mild to moderate. In one animal cerebrospinal fluid contained a high percentage of eosinophils but peripheral blood cell counts were within normal limits. Treatment with dexamethasone, diazepam and vitamin E was unsuccessful. The prognosis for bettongs with this disease is poor. The susceptibility of this species to this disease has implications for enclosure design.  相似文献   
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65.
Freshly-harvested blue-green algae (20 t ha?1) or Azolla (20 t ha?1) were incorporated into a waterlogged rice soil and changes of redox-potential and the availability of nitrogen and phosphorus were measured periodically. The soil progressively became reduced where blue-green algae or Azolla had been incorporated. The rate of N release from Azolla was more rapid than from blue-green algae and the amounts released after 7–35 days of flooding were between 41 and 76% and 12 and 35% respectively. Increased P availability was also recorded in soil following the incorporation of blue-green algae or Azolla and reached highest values after 21 days incubation.  相似文献   
66.
We analyzed data from a long-term rice–wheat cropping sequence to evaluate the effects of integrated nutrient management (INM) on yield trends and sustainability, nutrient balance and soil fertility of the system. After 30th cycle, grain yield of both the crops significantly declined under control and highest rice and wheat grain yields were obtained when 50% N supplied through green manure and farm yard manure, respectively. The magnitude of yield slope under INM was found considerably higher than 100% recommended fertilizer (RDF). Sustainable yield index (SYI) for both the crops were found lower in control but considerably higher with the 100% RDF and under INM. The soils under all the treatments suffered an apparent loss of K and N (except where organics replacing 50% N). Correlation study also reveals K is the sole factor for the yield sustainability as apparent K balance was negatively correlated with SYI and yield slope.  相似文献   
67.
The identification of suitable crop varieties that respond best to organic management is the key to achieving better crop yields. A field experiment was conducted during the winter season of 2005–2006 and 2006–2007 at Almora (Indian Himalayas) to evaluate the performance of five varieties of garden pea (Pisum sativum L.) and changes in the soil properties under organic and integrated nutrient management (INM) systems. The yield reduction under organic management was 14.4% in 2005–2006 and 10.1% in 2006–2007 compared with INM. Among the garden pea varieties ‘Vivek Matar 9’, ‘Vivek Matar 8’ and ‘Azad pea 1’ produced similar but significantly higher pod yield compared to other varieties. The soil pH, organic carbon, and microbial activities in terms of dehydrogenase and phosphatase (acid and alkaline) were higher in the plots under organic management compared to INM. The latter, however, had higher activity of urease, and N, P, and K contents in soil. We conclude that at least 15–20% price premium for organic garden pea may be required to offset the higher cost of cultivation and low yields under organic production system. Among the garden pea varieties, ‘Azad pea 1’, ‘Vivek Matar 8’ and ‘Vivek Matar 9’ were found suitable for organic cultivation.  相似文献   
68.
Timber species grouping (TSG) is essential for meaningful and cost-optimal use of wood. Bangladesh forests are exceedingly diverse and comprise many woody species which are potentially suitable for versatile uses including structural materials. Traditionally, widely known tree species are used for structural timber because technological properties of most of the species are poorly known. In this study, a hierarchical agglomerative cluster analysis based on three selected wood properties [i.e., wood density, modulus of elasticity (MOE) and modulus of rupture (MOR)] of seventy-nine timber species was done. The clustering process led to the formation of four distinct species groups [i.e., very low (TSG1), low (TSG2), medium (TSG3) and high (TSG4)]. However, the species grouping patterns also varied from trait to trait. This might be due to moderate relationship between density and MOE (r 2 = 0.46) or MOR (r 2 = 0.52). Species of the TSG1 group are mainly characterized by extremely low trait values, while the TSG4 group consists of species having exceedingly high trait values. The TSG2 and TSG3 groups are characterized by low and medium trait values. Hence, it is suggested to select suitable species from these groups, particularly the lesser known high-quality species in afforestation and reforestation programs to meet future timber demand in Bangladesh.  相似文献   
69.
AIMS: To assess whether stoats (Mustela erminea) would eat small baits containing 0.1% sodium monofluoroacetate (1080); whether they would die from it; how long it would take to kill them; and to document the behaviour of 1080-intoxicated stoats.

METHODS: Stoats were offered 1-g baits of two semi-fluid formulations containing 0.1% 1080, presented in open dishes, and their subsequent behaviour was monitored by video and direct observation. Muscle samples from stoats that died were analysed for 1080 residues.

RESULTS: There was no significant difference between two types of bait with regard to acceptance, mortality, and time to death, and behavioural effects were similar; consequently, results from the two types of bait were combined. Twelve of 14 stoats offered the baits ate them voluntarily, and a 13th licked bait off its fur; all 13 died between 1 h 15 min and 4 h 7 min (mean 2 h 38 min) later. At first (range 29 min — 2 h 7 min, mean 1 h 1 min), their behaviour appeared to be normal. Ataxia and hyperactivity were the first behavioural signs of poisoning, and lasted 2 min — 1 h 40 min (mean 26 min). This was followed by recumbency with convulsions and rapid breathing (range 16 min to 2 h, mean 58 min), then recumbency with limited activity and progressively shallow breathing prior to death (range 1–51 min, mean 33 min). Stoats became non-responsive to a light being turned on, or to touch once recumbency became sustained.

Residues of 1080 were found in muscle tissue of all 13 dead stoats, at concentrations ranging from 0.075 μg/g in a 287-g male that died 4 h 7 min after eating only 0.74 g of bait, to 2.5 μg/g in a 254-g female that died 2 h 42 min after taking a whole 1-g bait.

CONCLUSION: Stoats will voluntarily take small (1-g) baits containing a lethal dose of 1080 at 0.1%, and die from it comparatively rapidly for a mammalian carnivore.  相似文献   
70.
Summary

A field experiment was conducted on mango (Mangifera indica L.) to study the effects of farmyard manure (FYM) on soil organic carbon (SOC) content and on the build-up of fertility over three growing seasons (2006–2007, 2007–2008, and 2008–2009) at Bhubaneswar, Orissa, India. Five treatments, including the application of FYM at 5.0 kg plant–1, 7.5 kg plant–1, or 10.0 kg plant–1, the recommended dose of a chemical fertiliser (RDF; N:P:K=75:20:60), and a non-fertilised control, were evaluated in a randomised block design. The results indicated that SOC contents increased significantly in the FYM-treated plots. The highest SOC density (554 g m–2) and stock (5.55 Mg ha–1) were recorded in the treatment with FYM at 10 kg plant–1. The rate of increase in SOC density was highest (193 g m–2 year–1) with FYM at 10 kg plant–1, and lowest in the untreated control (15 g m–2 year–1). Regular addition of FYM had a positive effect on the build-up of soil fertility. However, the greatest increases in soil N, P, K contents were in the 7.5 kg plant–1 FYM treatment (means = 319.9, 19.1, and 270.8 kg ha–1 for N, P, K, respectively). Farmyard manure significantly influenced the growth parameters of mango trees over the three seasons. There was a positive and linear relationship between increasing rates of application of FYM and trunk cross-sectional area.  相似文献   
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