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91.
M. Paul Pener Amir Ayali Gal Kelmer Blank Bennettov Vclav Nmec Martin Rejzek Zdenk Wimmer 《Pest management science》1997,51(4):443-449
Effective treatment with juvenile hormone analogues (JHAs) of early penultimate or early last-instar locust hoppers induces a supernumerary ‘extra’ nymphal instar. These ‘extra’ nymphs, also termed ‘adultoids’, die in the course of, or shortly after, an ‘extra’ moult. Less effective treatment results in imperfect adults with crumpled twisted wings which presumably limit their flight and migratory abilities. Extremely effective treatment leads to death in the next moult. Comparing dose-response relations of (7S)-methoprene, fenoxycarb, pyriproxyfen and a new JHA, R70-1 (ethyl cis-N-{2-[4-(2-hydroxycyclohept-1-ylmethyl)phenoxy]ethyl}carbamate), we revealed that route of administration, instar of the recipient hopper, and species may alter over 1000-fold the ED50 for the same JHA. Locusta migratoria migratorioides is much more susceptible to JHAs than Schistocerca gregaria. The lowest ED50 found to induce adultoids and subsequent death in the ‘extra’ moult was 0·12 μg pyriproxyfen injected in olive oil to early penultimate instar hoppers of L. m. migratorioides (about 0·5 μg g-1 fresh weight). R70-1 was more active than pyriproxyfen following the more practical topical application to early last-instar hoppers of L. m. migratorioides, 5·9 μg and 46 μg per hopper, respectively (about 10 μg g-1 and 78 μg g-1 fresh weight). The high susceptibility of last-instar L. m. migratorioides nymphs to topically applied R70-1 is promising from the practical standpoint. ©1997 SCI 相似文献
92.
Mojtaba Mohammadi Arani Amir Parviz Salati Omid Safari Saeed Keyvanshokooh 《Aquaculture Nutrition》2019,25(4):854-861
This study was carried out to assess the effects of Pediococcus acidilactici on zebrafish (Danio rerio). Different levels of P. acidilactici including 0, 1 × 106, 2 × 106, 4 × 106 and 8 × 106 colony‐forming unit per g of the diet (cfug?1) were examined in fish with 120 ± 10 mg weight for 60 days in a completely randomized design. The results showed that the best growth indices were recorded in group 4 × 106 cfug?1 (p < 0.05). The highest number of total viable count and lactic acid bacteria of intestine were found in group 4 × 106 cfug?1 (p < 0.05). The maximum activity of digestive enzymes including amylase, lipase, protease and alkaline phosphatase was observed in group 4 × 106 cfug?1. The highest activity for superoxide dismutase was recorded in group 4 × 106 cfug?1 while catalase, glutathione peroxidase and glutathione reductase showed the highest activity in group 8 × 106 cfug?1. The most growth inhibition zone of Aeromonas hydrophylla, Flavobacterium columnare, Vibrio anguillarum and Edwardsiella tarda was found in group 4 × 106 cfug‐1 (p < 0.05). Therefore, P. acidilactici as a probiotic improved growth and immunity of the zebrafish and could be used by zebrafish farmers. 相似文献
93.
Morteza Longbaf Dezfouli Amin Ghaedtaheri Saeed Keyvanshokooh Amir Parviz Salati Seyed Mohammad Mousavi Hossein Pasha‐Zanoosi 《Aquaculture Nutrition》2019,25(6):1422-1430
This study was conducted to investigate effects of and interactions between nanoselenium (NanoSe) and nanomagnesium (NanoMg) on growth, humoral immunity, serum biochemistry and antioxidant capacity of juvenile Asian seabass Lates calcarifer reared in freshwater. Four groups of fish with an average weight of 32.78 ± 2.23 g were fed one of the experimental diets for 6 weeks: (a) control (basal diet); (b) NanoSe (basal diet + 4 mg NanoSe/kg diet); (c) NanoMg (basal diet + 500 mg NanoMg/kg diet); and (d) combination (basal diet + 4 mg NanoSe/kg diet + 500 mg NanoMg/kg diet). Fish fed with NanoSe‐supplemented diets (NanoSe and combination) showed higher weight gain, specific growth rate and feed intake. The combination of NanoSe and NanoMg enhanced the immune response. Also, fish fed on combination diet showed higher serum alanine aminotransferase and aspartate transaminase levels but lower glucose concentration. The activities of liver superoxide dismutase, glutathione peroxidase and catalase were not different among all groups, but liver malondialdehyde level was lower in fish fed diets supplemented with NanoSe and/or NanoMg. It could be concluded that NanoSe improved growth performance; the combination of both NanoSe and NanoMg enhanced humoral immunity; and NanoSe and/or NanoMg improved antioxidant capacity in Asian seabass. 相似文献
94.
95.
Immunohistochemical localization of endothelial and inducible nitric oxide synthase within neurons of cattle with rabies 总被引:1,自引:0,他引:1
Shin T Weinstock D Castro MD Hamir AN Wampler T Walter M Kim HY Acland H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(5):539-541
The expression of constitutive endothelial nitric oxide synthase (eNOS) and inducible NOS (iNOS) in the brains of cattle with natural rabies was studied. Increased expression of eNOS was detected in neurons of the brain stem and Purkinje cells of cerebellum. By contrast, iNOS was diffusely localized in the cytoplasm of affected neurons, and some inflammatory cells were positive. eNOS and rabies antigen were co-localized in inclusion bodies (Negri bodies) in neurons. The specific localization of eNOS, but not iNOS, in the Negri bodies suggests that eNOS is involved in the formation of rabies virus inclusion bodies. 相似文献
96.
Tafti AK Rashidi K 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2000,47(7):487-495
From a pathological examination of the intestinal tracts of 1590 goats killed at slaughterhouses in the Fars Province of Iran, 59 cases (3.71%) were suspected, on gross examination, of having paratuberculosis. The diagnosis was confirmed by histopathological study and Ziehl-Neelsen staining of direct smears of rectal faeces. On the basis of severity of involvement of the terminal ileum and mesenteric lymph nodes, the microscopic lesions were classified to mild, moderate and severe forms. Caseous necrosis and calcification were observed only in the mesenteric lymph nodes. High numbers of acid-fast organisms were present in the epithelioid macrophages of the intestine but were inapparent or sparse in the mesenteric lymph nodes. On microscopic examination, 13.5% of the suspected animals were found to have paratuberculosis, in comparison with 3.38% by direct faecal smears. In addition, 30.5% and 15.3% of the animals were diagnosed as having eosinophilic enteritis and linguatulosis, respectively. These findings stress the importance of a careful histopathological examination of the intestines and mesenteric lymph nodes for the diagnosis of paratuberculosis in goats. 相似文献
97.
98.
99.
Summary Water application pattern, WAP, is one of the most important factors that determine the instantaneous and the cumulative application rates of moving irrigation machines. The mathematical background of a procedure to predict and design the WAP of moving irrigation machines is introduced. It includes a mathematical analysis of the effect of pressure head, height and spacing between emitters on the WAP, and a nomograph that presents this analysis graphically and illustrates the design procedure of the application pattern of irrigation machines.Abbreviations
P()a
water application rate at a normalized radial distance from the emitter [m/s]
-
ka
number of linear segments needed to represent the pattern
- s/Ra
normalized radial distance from the emitter
-
Ra
wetted radius [m]
-
sa
radial distance from the emitter [m]
-
n
j n
i/ha
normalized water application rate at point
-
j, ha
maximum water application rate [m/s] n
j water application rate at point j [m/s]
-
j
=m
j/Ra
normalized radial distance of point j from emitter
-
m
ja
radial distance of point
-
ja
from emitter [m], CWAP
- (x)a
Cumulative Water Application Pattern: amount of water per unit area applied at a distance
-
xa
from the travel path of the emitter [m3/m2]
-
xa
distance from the travel path of the emitter [m]
-
T
xa
time of application at a distance
-
xa
from the travel path of the emitter [s]
-
va
velocity of propagation of the machine [m/s]
-
k
1a
the outmost linear segment that its radial distance from the emitter
-
m
k1a
is smaller than the distance of the travel path from the emitter
-
x, T
ja
time at which the
-
j
tha
linear segment (ring) stops influencing the point located at a distance
-
xa
from the emitter
-
1,
2,
3a
dimensionless numbers derived by dimensional analysis
-
ua
water jet velocity [m/s]
-
ga
gravity acceleration [m/s2]
-
da
nozzle diameter [m], v kinematic viscosity [m2/s]
-
Ha
emitters height [m]
-
, a
regression analysis coefficients
-
Paa
Pattern fit coefficient for water application
-
F(r)a
normalized desired water application pattern [1/m]
-
f(r)a
normalized actual water application pattern [1/m]
-
La
common distance on which
-
F(r) and f(r)a
are defined [m], SP spacing interval between emitters [m]
-
DSa
dimensionless spacing interval between emitters
-
DSa
variation of dimensionless spacing interval
-
Paa
variation of Pa coefficient
-
Pa
pressure head [kPa] 相似文献
100.