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101.
Laying hens were inoculated orally, intracloacally (IC), or intravenously (IV) with Salmonella enteritidis phage type 8 isolates from a human (E700-87) eggs (Y-8P2), or the ovary of a hen (27A). Oral or IV inoculation of 2 x 10(8) to 4 x 10(8) colony-forming units (CFU) of E700-87 caused depression, anorexia, reduced egg production, diarrhea, and some mortality. Lower doses resulted in milder clinical signs. S. enteritidis was cultured from the shells of a few eggs but not from egg contents. Fecal shedding persisted for up to 6 weeks in some birds. Isolate Y-8P2 (10(6) CFU) also caused anorexia, diarrhea, and a drop in egg production. Hens inoculated orally or IC were less severely affected than those inoculated IV. Fecal shedding was intermittent and lasted up to 18 days. Eggshells from the IC-inoculated birds had the highest rate of contamination, and S. enteritidis was isolated from the albumen of 11 and yolk of three of 726 eggs. Oral inoculation of 10(6) CFU of isolate 27A resulted in a bacteremic infection with seeding of the liver, spleen, peritoneum, ovule, and oviduct. However, the birds remained clinically normal with normal egg production. S. enteritidis was cultured from the yolk and albumen of a small number of eggs until 11 days postinfection. Antigen prepared from S. enteritidis detected antibody in more sera than did commercially available S. pullorum antigen in agglutination tests.  相似文献   
102.
Forty-seven nesting green turtles (Chelonia mydas) were examined for parasitic pathogens. Four species of cardiovascular flukes (Digenea: Spirorchiidae), Learedius learedi, Hapalotrema postorchis, Monticellius indicum and Amphiorchis solus were collected from 39 of 40 of the turtles, and Neospirorchis species were identified in seven of the 47 by histological examination. The pathological changes associated with the spirorchiids and their eggs included aneurysms, arteritis of great vessels with dark nodular thickenings, endocarditis, haemorrhagic lesions, thrombi, vasculitis, and granulomatous reactions in all the turtles. Ozobranchus branchiatus (Hirudinea: Ozobranchidae) leeches were found on the skin of 27 of the 47 turtles and were associated with traumatic purulent and ulcerative dermatitis. Oesophagitis associated with Rameshwarotrema uterocrescens (Digenea: Pronocephalidae) was recorded in 11 of 43 of the turtles. Petechial haemorrhages and unspecific crater-like ulcerated lesions on the gastric mucosa associated with Charaxicephaloides species and Charaxicephalus robustus (Digenea: Pronocephalidae) were observed in four of 40 of the turtles. Cholycystitis and ectasia of mucosal glands associated with Rhytidodoides similis (Digenea: Rhytidodidae) were observed in one of the 47 turtles. Fibropapillomas were observed on the skin of one turtle and fibromas on the skin of two of them.  相似文献   
103.
Knowledge of how roads affect forest biodiversity can be improved by measuring the responses of indicator species to complex environmental gradients caused by these infrastructures. We studied litter invertebrate species responses to road edges in laurel and pine forests in Tenerife, Canary Islands. We sampled invertebrates from litter and assessed the environmental variation related to road proximity. We also assessed the effect of relevant environmental predictors on a diverse array of potential indicator species. We applied canonical ordination and non-parametric regression (Lowess) to classify invertebrate species responses to roads and their associated gradients. Three types of responses to road edge proximity were defined for the most common invertebrate taxa: edge-preferring or edge specialists, interior-preferring or edge-avoiders, and edge-indifferent or neutral species. Those species appearing most frequently and with higher population density between 1 and 20 m from the edge (commonly peaking at 10 m from the road) were categorized as edge-preferring. We classified taxa attaining peak population densities at or beyond 60 m from the edge (and most commonly 100 m) as interior species. Edge-neutral species were those without an evident pattern of stabilization in abundance along the gradient and with peaks in abundance at varying distance intervals. These edge litter communities contain a high native and endemic diversity but also a significant density of alien fauna. The specific patterns of penetration of road edge effects on invertebrate species should be seen as having a pervasive and cumulative impact considering the exceptionally large number of roads in these forests and the high population densities of alien invertebrates. Future management plans for forest conservation on the Canary Islands should include the highly altered but valuable litter communities along road edges.  相似文献   
104.
This paper aims to enrich the analysis on the significance of the individual firm resources in a cluster and the effects of diverse cluster relationships, including local and non‐local ones, on firms' innovation capacity. On questioning the commonly accepted direct and positive impact, we explore the joint and non‐linear effects of internal resources and inter‐organisational relationships on innovation. Data from 251 footwear manufacturers located in the Spanish Vinalopó cluster were used to explore the proposed causal relationships. According to findings, the impact of each factor on product innovation is not homogeneous. Internal innovation efforts and cooperation with local suppliers positively affect the creation of new products, while collaboration with local customers and extra‐cluster linkages presents an inverted U‐shaped relationship with product innovation. Finally, a number of implications may be drawn for policy makers, practitioners, and future research.  相似文献   
105.
An experiment was conducted to evaluate the effect of excess levels of Leu and Lys on the expression of b0,+ and CAT‐1 mRNA in jejunum, liver and the muscles Longissimus dorsi (LDM) and Semitendinosus (STM). Twenty pigs with an average initial BW of 16.4 ± 1.7 kg were used in a Randomized Complete Block. Dietary treatments (T) were as follows: T1, basal diet; T2, basal plus 3.5 g l ‐Lys/kg diet; T3, basal plus 1.5 g l ‐Leu/kg diet; T4, basal plus 3.5 g l ‐Lys plus 1.5 g l ‐Leu/kg diet. Diets in T1 and T3 met 100% the requirement of Lys for pigs within the 10 to 20 kg body weight range; diets in T2 and T4 contained 35% excess of Lys. Also, diets in T1 and T2 supplied 104%, whereas diets in T3 and T4 supplied 116% the requirement of Leu. The expression of b0,+ in jejunum was reduced (p = 0.002) because of the supplementation of l ‐Leu, but l ‐Lys supplementation had no effect (p = 0.738). In contrast, the expression of b0,+ in STM (p = 0.012) and liver (p = 0.095) was reduced by the high level of Lys, but Leu had no effect (p > 0.100). CAT‐1 expression in STM increased by high Lys (p = 0.023) and Leu (p = 0.007) levels. In liver, the expression of CAT‐1 substantially increased (p = 0.001) because of Lys. In conclusion, excess levels of dietary Lys and Leu affect the expression of cationic amino acid transporters, and this effect varies depending on the studied tissue.  相似文献   
106.
The direct and maternal genetic effects were estimated for the preweaning growth of Retinta calves with a multitrait model across parities, using a longitudinal approach with random regression models (RRM). The 120 (P120) and 180 days (P180) weights (5972 calves) were considered as different traits in each calving. The heritability of direct effect across parities was on average 0.37 for P120 and 0.58 for P180, slightly higher than the estimates by univariate (0.30 and 0.56) and bivariate models (0.30 and 0.51, respectively). The heritability for maternal effects was 0.16 for P120 and 0.26 for P180 and very similar by uni‐ (0.16 and 0.23) and multivariate model (0.16 and 0.22, respectively). The correlation between direct and maternal effects by RRM showed a pronounced antagonism ?0.64 for P120 and ?0.78 for P180), likewise uni‐ (?0.62 and ?0.72) and multivariate case (?0.64 and ?0.74, respectively). The preweaning weights should be considered as different traits across parities, because the genetic correlations were different from unity. The RRM also allowed us to estimate all the parameters throughout the calving trajectory of the cow. The use of multiple traits RRM across parities can provide very useful information for the breeding programmes.  相似文献   
107.
The objective of this study was to characterize the effect of dose and type of cloprostenol (CLO) on the luteolytic response of dairy cattle during the Ovsynch protocol under different oestrus cycle and physiological characteristics. Twelve non‐lactating dairy cows and 111 lactating dairy cows were used in three experiments. In Experiment I, cows were synchronized so that they had only a 5.5‐ to 6‐day‐old corpus luteum (CL) at the time of the prostaglandin F (PGF) treatment of Ovsynch. In Experiment II, cows were synchronized so that they had at least a CL of approximately 14 days old at the time of PGF treatment and an accessory CL if they had responded to the first GnRH of Ovsynch. Furthermore, in each experiment, cows received either a standard or a double dose of d‐CLO as the luteolytic treatment. In Experiment III, lactating cows were blocked by parity and assigned to one of three luteolytic treatments during Ovsynch: 500 μg d,l‐CLO, 150 or 300 μg of d‐CLO. In Experiment I, the dose of d‐CLO had an effect (p = 0.08) on the percentage of cows with full luteolysis, but not in Experiment II (p > 0.1). More cows in Experiment II had full luteolysis than did cows of Experiment I (87% vs 58%, respectively; p = 0.007). In Experiment III, 87.1%, 84.4% and 86.2% lactating dairy cows had full luteolysis and 37.8%, 36.8% and 36.1% of cows became pregnant after treatment with 500 μg d,l‐CLO, 150 or 300 μg of d‐CLO, respectively (p > 0.05).  相似文献   
108.
Summary

Plants of Rosmarinus officinalis were submitted to water and salt stress, independently. The effects of water or salt stress on growth, water relations and gas exchange were investigated in order to understand the tolerance and adaptative mechanisms of R. officinalis to these types of stress. Under both stress conditions, plants developed avoidance mechanisms to minimise water loss based on morphological and physiological changes (e.g., reduction of plant biomass and leaf area, stomatal closure). Only under salt stress conditions were treated plants able to maintain turgor via osmotic adjustment, which was achieved by the uptake of Na+ and Cl ions. Osmotic adjustment was not observed in R. officinalis plants submitted to water stress. The results indicate that high accumulation of Na+ and Cl ions was responsible for the growth reduction observed in salinised plants. However, the growth reduction observed in water-stressed plants was caused by a dehydration process.  相似文献   
109.
The intake of traditionally consumed wild edible species is nowadays receiving renewed attention, due to the recognition of their potential benefits for human health. This paper represents a contribution to the knowledge of the chemical composition of different wild and under-utilized vegetables of the Mediterranean area, concerning their organic acid profile and the distribution of ascorbic and dehydroascorbic acids as vitamin C activity. Fifteen species, belonging to ten botanical families, were selected, analyzing two samples of each one from two different localities of Central Spain. Each species showed a specific organic acids fingerprint. Citric acid was 90% of total organic acids in Tamus communis; malic acid was the major one in Humulus lupulus, Taraxacum obovatum and Cichorium intybus, and oxalic acid was the main organic acid in Beta maritima, Papaver rhoeas, Silybum marianum, Foeniculum vulgare, Rumex pulcher, Silene vulgaris, Scolymus hispanicus, Rumex papillaris and Bryonia dioica. The distribution of ascorbic and dehydroascorbic acid was highly variable. Mean values for total vitamin C ranged between 1.5 and 79.4 mg/100 g. Tamus communis, R. pulcher, S. vulgaris and B. dioica, showed the highest content of AA, and together with F. vulgare and H. lupulus, the highest total vitamin C content. These results can be useful to complete food composition databases with the inclusion of wild vegetables from the Mediterranean area, contributing to enhance the diversity of the diet as well as its nutritional quality.  相似文献   
110.
Traditional use of noncultivated vegetables has decreased with the development of agriculture and global supply chains. However, some species are still consumed as part of our traditional Mediterranean diet. Plants are among the most important sources of natural antioxidants for retarding lipid oxidative rancidity in foods or for pharmaceutical applications against chronic diseases related to free radicals production. The present study reports tocopherols composition and antioxidant activity of eight wild greens traditionally used in Spain. According to the edible part consumed, two groups were differentiated. Leafy vegetables whose young stems with leaves are consumed (Apium nodiflorum (L.) Lag., Foeniculum vulgare Mill., Montia fontana L. and Silene vulgaris (Moench) Garcke), and wild asparagus whose young shoots with leaf buds scarcely developed are eaten (Asparagus acutifolius L., Bryonia dioica Jacq., Humulus lupulus L. and Tamus communis L.). Among the leafy vegetables, Silene vulgaris and Apium nodiflorum presented the highest antioxidant capacity and antioxidants contents. Among the wild asparagus, the highest antioxidant capacity was obtained in Humulus lupulus.  相似文献   
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