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11.
Genetic line and diet affect chicken heterophil activity and gene expression, and the combination of these factors can enhance disease resistance. This study evaluated the effects of immune modulating diets on heterophil/lymphocyte (H/L) ratio and heterophil chemokine expression in distinct genetic lines. Fayoumi and Leghorn chickens were fed a basal diet or immune modulating diets enhanced with β-glucans, ascorbic acid, or corticosterone. H/L ratios and heterophil gene expression in response to in vitro stimulation with Salmonella enteritidis (SE) were evaluated on days 1, 3, 7, and 21 of diet treatment. The stress-mimicking corticosterone diet influenced H/L ratio in the Leghorn line, but not the Fayoumi line, suggesting resistance to stress-induced immunosuppression in the Fayoumi line. Leghorn line H/L ratios were increased on days 1 and 3 of corticosterone diet treatment, but not days 7 or 21. Expression of CXCLi2 by SE stimulated heterophils was higher in the Leghorn line, suggesting that Leghorns rely more heavily on inflammatory response than do Fayoumis. Corticosterone diet was associated with reduced CXCLi2 expression in heterophils from both lines. Dietary β-glucan or ascorbic acid did not affect H/L ratio or CXCLi2 expression, suggesting that benefits of these immunomodulators may not be evident in healthy birds.  相似文献   
12.
Among grow-to-finish pigs from 10 herds in Alberta and Saskatchewan, 23 (16%) of 144 fecal samples were culture-positive and 40 (28%) of 144 pigs were seropositive for Salmonella. With a Bayesian model specifying dependence between the 2 tests, the sensitivity (Se) of culture and real-time polymerase chain reaction (RT-PCR) was 79% to 86%, depending on the cut-off value for the enzyme-linked immunosorbent assay (ELISA). Culture specificity (Sp) was assumed to be 100%; RT-PCR Sp was found to be 94%. The ELISA Se was 76% and 51% at optical density cut-off values ≥ 20% and ≥ 40%, respectively; the Sp was 94% at each cut-off value. The model showed some sensitivity to ELISA prior information, the ELISA Se being approximately 8% lower when informative prior information was specified in the model. When there was no adjustment for dependence between culture and RT-PCR, the posterior estimates for both culture and RT-PCR Se were 11% higher than with the conditional-dependence model and had considerably narrower probability intervals, which suggests that correlation between culture and PCR is important and should be adjusted for in future studies.  相似文献   
13.
The presence of American liver fluke (Fascioloides magna) in Croatian wild ruminant species was detected for the first time in January 2000. At the same time, the problem of adequate parasitological monitoring and treatment appeared in the captive deer population. Quarantine and health screening protocols, as well as migration and transportation influence had to be evaluated in red deer husbandry. Non-invasive methods were introduced to estimate the prevalence of F. magna in the semi-farm rearing system. Coprological analysis has been performed on 264 faecal samples. The most effective antiparasitic treatment was implemented on herd and individual treatment. Treatment was extended to the free-ranging population of deer in the same region.  相似文献   
14.
New alien species of aphids (Illinoia liriodendri (Monell), Wahlgreniella nervata (Gillete), Takecallis arundicolens (Clarke) and Tinocallis takachihoensis Higuchi) have been found for the first time in Serbia. These records are new for the Balkan Peninsula. Data of Ericaphis scammelli (Mason), species recently mentioned in Serbia, are also presented in the text. The species have been found during the last five years at four sites (Belgrade, Zemun, Mladenovac and Bojnik) on five cultivated plants. Ericaphis scammelli is a pest of blueberry and a vector of Blueberry scorch virus. The other four develop colonies on decorative plants: I. liriodendri has been found on Liriodendron tulipifera, W. nervata on Rosa sp., T. arundicolens on Pseudosasa japonica and T. takachihoensis on Ulmus x hollandica. The origin of three of the species (E. scammelli, I. liriodendri and W. nervata) is North America and two (T. arundicolens and T. takachihoensis) have come from East Asia. Their morphology, biology and the damage they inflict are discussed here, as well as their potential economic and environmental threat. Only parthenogenetic viviparous females of all 5 species have been collected. Their biology has not been studied enough in Europe and needs further examination. Original drawings of all species are presented.  相似文献   
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Five groups of laying hens were treated with different gizzerosine doses (0, 2.5; 5.0; 7.5; 10.0 mg/kg/body weight of gizzerosine) daily over a 21-day period to determine the serum concentrations of 1.25-dihydroxycholecalciferol (1,25(OH)2D), total calcium, inorganic phosphorus and magnesium. Blood samples were taken on days 7, 14, and 21 of the experiment. The concentration of 1,25(OH)2D remained unchanged after day 7 in the gizzerosine-treated birds compared to the control group. After 14 days, it was significantly lower in the birds receiving. gizzerosine, compared with the control group. On day 21, 1,25(OH2)D concentrations were also significantly decreased in all 4 gizzerosine-treated groups compared with the control hens. The serum total calcium, inorganic phosphorus and total magnesium concentrations varied significantly, but irregularly, during the period of the study.  相似文献   
17.
During the years from 1993 to 2000, 183 strains of Pseudomonas aeruginosa were isolated from different pathological specimens originating from dogs. Antimicrobial susceptibility patterns against 10 antipseudomonal agents were obtained on 183 P. aeruginosa strains. In vitro antimicrobial susceptibility testing was performed using the disk diffusion method (Kirby-Bauer). Antimicrobial susceptibility profiles showed that among beta-lactam antibiotics, imipenem was the most active compound. Out of the 183 strains tested, 96.7% were sensitive to imipenem. Cefoperazone showed good in vitro activity against 86.9% of the tested strains. Against ceftazidime, 77.0% of strains showed sensitivity. An old penicillin, carbenicillin, gave only 71.6% sensitive strains. Sensitivity to amikacin was 87.4% and it was 83.1% to gentamicin. Pipimedic acid, a first-generation quinolone, was the least active compound of all those tested, 47.0% were resistant. The in vitro sensitivity against enrofloxacin showed that 71.0% strains were sensitive and 26.2% showed resistance. Almost all strains tested, 93.4%, were susceptible to ciprofloxacin and marbofloxacin. Besides imipenem, the quinolone antibiotics, marbofloxacin and ciprofloxacin were the most effective against P. aeruginosa strains isolated from dogs.  相似文献   
18.
During the spring of 1996 and autumn of 1997 unusual mortality outbreaks among rainbow trout fry and yearlings occurred at two different trout farms, resulting in mortality of 20 and 10 per cent, respectively. Generally, the affected fish, swimming at the water surface, were reluctant to eat and were dark pigmented with visible haemorrhages around and within the oral cavity. Bacterial isolates from moribund fish from both cases were identified as Yersinia ruckeri by standard biochemical tests and API 20E. The isolated strains were found to be sensitive to tetracycline, chloramphenicol, co-trimoxazole, nalidixic acid, flumequine, enrofloxacin, carbenicillin and gentamicin. Microplate agglutination assay confirmed that both isolates belonged to serotype O1. The pathogenicity of the isolated bacteria was confirmed by challenge experiment. Titres of specific antibodies were determined in the sera of survivors. The titre was highest on the 21st day postchallenge and was detectable until the 81st day.  相似文献   
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20.
The parasitoids (Hymenoptera, Braconidae, Aphidiinae) of the cowpea aphid, Aphis craccivora Koch, were investigated throughout two far distant provinces, Tehran and Sistan-Baluchestan. Colonies of the cowpea aphid were collected from different host plants and reared under laboratory conditions until the parasitoids emerged. The aphids were parasitized by an expected range of parasitoids. The species were Aphidius colemani Viereck, Lysiphlebus fabarum (Marshall), Lysiphlebus confusus Tremblay and Eady, Lysiphlebus testaceipes (Cresson), Binodoxys acalephae (Marshall), Binodoxys angelicae (Haliday), Praon volucre (Haliday) and Ephedrus persicae Froggatt. L. testaceipes is reported here for the first time in Iran. The most common species was L. fabarum followed by B. acalephae and L. confusus. A key is provided for identification and host plant associations are considered.  相似文献   
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