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Tropical Animal Health and Production - The effect of multinutrient antioxidant treatment on sheep naturally infected with FMD virus was investigated in terms of general health conditions, serum...  相似文献   
33.
Abstract

At Shandaweel Experimental Station, Upper Egypt, chlorthal, nitrofen, fluorodifen and SMA were tried out either pre-em. or pre- and post-em. in onion nurseries. Data are presented with statistical analyses.

Good results were obtained with chlorthal at 4.5 + 4.5 lb/feddan*, nitrofen (3 + 3 lb/feddan) and fluorodifen (1.5 + 1.5 lb/feddan) pre- and post-em. 4 and 18 days respectively after sowing. The combination of chlorthal (4.5 lb/feddan) pre-em. + fluorodifen (1.0 lb/feddan) post-em. also gave good results.  相似文献   
34.
The potential of the two predators,Chrysoperla carnea Steph. andCoccinella undecimpunctata Reich., as well as the two parasitoidsDiaeretiella rapae andEretmocerus mundus in an open field and under green house were conducted after several releases againstAphis gossypii, A. fabae, Brevicorine brassicae andBemisia tabaci. Double releases ofC. carnea (1∶5 predator∶aphids) achieved 100% reduction inA. gossypii after 12 days. A single release ofC. undecimpunctata (1∶50 predator∶aphids) resulted in 99.97% reduction in the same aphid. Releasing ofD. rapae to controlB. brassicae at the rate of 1∶50 resulted in 29% parasitism. ReleasingE. mundus for the control ofB. tabaci in cabbage at the rate of 5 adults/m2 resulted in 32% parasitism. Three releases ofC. undecimpunctata adults in a greenhouse cultivated with soybean, decreasedA. fabae population from 207 to 7.6 aphids/plant.  相似文献   
35.
A new technique was performed to simulate exposure of the host Pieris rapae larvae to both botanical treatment and the parasitoid Hyposoter eheninus in different sequences. It was found that: host larvae subjected to both parasitoid and 1?% neem treatment showed significant or insignificant reductions both in pupal formation as well as adult emergence percentages when treatment preceded or followed parasitism, respectively. Both neem treatments revealed significant prolongation in the development of unparasitized and parasitized larvae (on average 4 to 5 days delay), whereas chinaberry caused significant prolongation only among parasitized larvae (on average 2.7 days delay in egg-larval duration). Fate of parasitism among untreated hosts was found to be faster than among neem-treated ones. Parasitism percentages among 1 and 0.5?% neem-treated third instar host larvae held 7 days before parasitism reached 3 and 2 times that achieved among those reared on untreated diet for the same period, ­respectively. It was concluded that prolongation of the preferred target instars of the host, due to neem treatments, increased the chance for parasitism. Nevertheless, treatment with neem at the LC50 level exhibited a great reduction in parasitoid progeny. However, a lower concentration (LC25) could reasonably potentiate parasitism without drastic losses in parasitoid emergence.  相似文献   
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Cryopreservation is a modern technique which assists in the preservation of genetic material from oocytes and embryos for a long time. However, elevated vulnerability to cryopreservation due to the large accumulation of intracellular lipids within oocytes or embryos avoids success of this method. These lipids remain the main crucial factor limiting survival rates of oocytes and embryos after thawing. Lipid ingathering in the oocyte cytoplasm augments lipid peroxidation (LPO) and oxidative stress increases the apoptosis process, declines the viability after thawing, declines cytoskeleton actin filament injuries, lowers the blastocyst rates and reduces cryotolerance in the early stages of embryo development. There have been several attempts to reduce the ingathering of intracellular lipids in oocytes or embryos during the cryopreservation process, in that way enhancing the competence of cryopreserved oocytes or embryos and increasing their viability. One of the most applied agents for chemical delipidation is forskolin. Forskolin exhibited a possible part in improving the oocytes cryopreservation through stimulating cyclic adenosine monophosphate (cAMP) production. The main purpose of cAMP modulation is to provide energy to sustain the mammalian oocytes´ meiotic arrest. The purpose of the existing article is to assess and offer more evidence concerning the forskolin utilization as a modulator of cAMP during the cryopreservation of oocytes and its influence on meiosis completion and the reorganization of cytoplasm, which are prerequisites for the development of oocytes in addition to the contribution to fertilization and subsequently, the development of embryos.  相似文献   
38.
The present trial was performed to evaluate the effect of dietary incorporation of dried Spirulina, Chlorella and their mixture on the immune status of Nile tilapia (Oreochromis niloticus) before and after artificial infection with pathogenic bacterium Aeromonas hydrophila (A. hydrophila). Two hundred and forty fish were divided into four groups: (a) a control group fed on a basal diet only, (b) a second group fed on a diet containing Spirulina 15%, (c) a third group fed on a diet containing Chlorella 15%, and (d) a fourth group fed on a diet containing a mixture of both Spirulina 15% and Chlorella 15%. At the end of the experiment (9 weeks), the four groups were experimentally infected with A. hydrophila for 7 days. Antioxidant enzymes, lysozyme and bactericidal activities and histopathological changes were determined just before the challenge test and 7 days post‐challenge. Significant (p ≤ 0.05) increases in fish body protein% before the challenge test and increases in serum antioxidant enzymes, lysozyme and bactericidal activity in the Chlorella and algal mixture groups before and after the challenge test were observed. Spirulina, Chlorella and their mixture groups significantly decreased serum malondialdehyde compared to the control group before and after the challenge test. Using Spirulina, Chlorella and their mixture mitigated the necrotic and degenerative changes induced by A. hydrophila and revealed well‐developed and multiple melanomacrophage centres. Thus, dietary Spirulina, Chlorella and their mixture inclusion in Nile tilapia fish proved to have a protective effect against A. hydrophila infection.  相似文献   
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