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151.
152.
1. Pullets (Ross Rangers) reared commercially either in cages or on deep litter were tested for their responses to small (0.38 × 0.43 m) and large (0.76 x 0.86 m) cages with wire floors and to small and large cages with litter floors.

2. When tested at 29 weeks of age, the birds' responses were significantly affected both by cage size (large preferred to small) and by flooring (litter preferred to wire).

3. No difference in cage preference was apparent between cage‐reared and litter‐reared birds either when they were first tested at 17 weeks or when they were re‐tested at 29 weeks. Birds do not have to be reared on litter in order to be attracted by it.  相似文献   

153.
The aim of the current study was to evaluate the impact of carnosic acid (CA), selenised yeast (YSe) and selenate (VISe) supplemented to diets, including fish oil (FO) and rapeseed oil (RO), on the content of fatty acids, total cholesterol (TCh), tocopherols and malondialdehyde in the fat located between the thigh muscles and the heart in lambs. Twenty-four male Corriedale lambs were divided into 4 groups of 6 animals. Animals were fed a diet with FO and RO (the control diet) or experimental diets containing RO, FO and CA with/without Se (as YSe or VISe). The experimental diets without/with YSe or VISe changed concentrations of fatty acids in the fat and heart compared to the control. All experimental diets increased the levels of c11c14C20:2, c5c8c11c14C20:4, c5c8c11c14c17C20:5 and the sums of long-chain polyunsaturated fatty acids (LPUFA) and conjugated linoleic acid isomers in the fat compared to the control. The experimental diet containing YSe or VISe increased the content of Se, TCh, c11c14C20:2, c8c11c14C20:3, c5c8c11c14C20:4, c5c8c11c14c17C20:5, c7c10c13c16c19C22:5, c4c7c10c13c16c19C22:6 and the concentration sum of n-3LPUFA, n-6LPUFA and tocopherols in the heart in comparison with the control diet and the diet containing only CA. Experimental diets reduced the concentration of malondialdehyde in the fat and heart in comparison with the control diet. Our dietary intervention has great potential for future practical and commercial implementations.  相似文献   
154.
In autumn 2009, the implementation of two successive acoustic surveys targeting juvenile anchovy (Engraulis encrasicolus) in the Bay of Biscay allowed us to monitor the changes in the spatial distribution and aggregation patterns of juveniles of this species during 45 days under fairly stable meteorological conditions. Juvenile anchovy changed its biological condition and behavior in a different manner in two distinct areas. In the Spanish sector, the juveniles migrated 20 nautical miles (n.mi.) towards the coast, but they remained on the shelf and near the surface during the whole surveyed period. As the advance towards the shelf break progressed, their area of distribution decreased, their density increased and the juveniles spread in fewer but heavier shoals. In the French sector, the juveniles also migrated from slope waters towards the coast at a similar velocity, but they crossed the shelf break into the continental shelf, where they increased their mean depth significantly until gradually adopting the typical nyctemeral migrations of adult anchovy. The mean length of the juveniles that adopted the nyctemeral migrations was significantly higher than that of the juveniles remaining at the surface, suggesting that body size is relevant to accomplish this change. Besides, the stronger temperature gradients between the shelf and oceanic waters in the Spanish sector, favored by a narrow shelf, may have acted as a barrier influencing the distinct observed spatial patterns in the two areas.  相似文献   
155.
In order to control growing problems associated with porcine circovirus type 2 (PCV2) several vaccines for piglets or sows were introduced recently. An objective of the study was to compare an efficacy of three different vaccination protocols in the herd with acute postweaning multisystemic wasting syndrome (PMWS) outbreak affecting 3-month-old pigs. All of three applied protocols, namely vaccination of sows, piglets or sows and piglets with Circovac proved to be efficacious in controlling of PMWS. All production parameters significantly improved after vaccination. Obtained values were as good as before the outbreak or even better as in case of average daily weight gains. However, decreased mortality before weaning was recorded only after vaccination of sows while in groups where piglets were vaccinated significantly lower mortality in fourth month of life was observed. The impact of different protocols on different parameters suggests that they could be adopted in herds with different porcine circovirus associated problems.  相似文献   
156.
The influence of treatment with steroidal (SAIDs) and non-steroidal (NSAIDs) anti-inflammatory drugs on inflammatory markers in thirty, 6-8 week old calves with induced bronchopneumonia was investigated. Animals received a single intravenous treatment with meloxicam (0.5 mg/kg body weight), flumethasone (0.05 mg/kg body weight) or sterile 0.9% NaCl (10 ml per animal). Body temperature, respiratory and heart rate, concentration of prostaglandins PGE2, PGF2alpha, thromboxane (TXB2), leukotriene (LTB4) and malonyldialdehyd (MDA) and proinflammatory cytokines i.e. tumor necrosis factor (TNFalpha) and interferon (INFalpha) were recorded in serum, bronchoalveolar lavage (BAL) and blood platelets (BP). A significant reduction of main inflammatory mediators PGE2, PGF2alpha,TXB2 and MDA after meloxicam treatment in calves with induced bronchopneumonia indicates a beneficial effect on the inflammatory processes. Contrary to effects observed by flumethasone, meloxicam induced an increase of LTB4 and INFalpha indicating that it is not immunosuppressive.  相似文献   
157.
158.
Indirect immunofluorescent assay for antinuclear antibodies (IIFA-ANA) on HEp-2 cell substrate is a widely used test for diagnosis of connective tissue diseases. Recently, serum-free fibroblast cell line McCoy-Plovdiv has been developed to provide an alternative substrate. The aim of the present study was to evaluate the diagnostic performance of IIFA-ANA on McCoy-Plovdiv cell substrate for systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) and compare it with that of the standard HEp-2 cell substrate. Sera from 72 patients with RA and 23 patients with SLE were tested with IIFA-ANA on both substrates. The control group consisted of 100 sera from healthy individuals. The agreement (Cohen's kappa) and the diagnostic performance (ROC analysis) of both methods were evaluated. IIFA-ANA on McCoy-Plovdiv cells proved to be comparable with the standard IIFA-ANA on HEp-2 cell substrate.  相似文献   
159.
Content of total and free amino acids in zooplanktonic food of fish larvae   总被引:3,自引:0,他引:3  
The content of total and free amino acids in freshwater planktonic rotifers (Brachionus sp.), copepods (Eudiaptomus zachariasi) and groups of Daphnia pulex, Ceriodaphnia sp. and copepodites (Cyclops strenuus) of different sizes was determined. The amino acid content of Artemia salina nauplii on hatching and during fasting was also determined.

Amino acid content was lowest in rotifers and highest in stage III–IV copepodites. The major free amino acids in Cyclops strenuus dry matter were 1.43% arginine, 0.22% histidine, 0.20% alanine, 0.15% glutamic acid and 0.11% lysine. Free arginine content decreased in the daphnids as they increased in size. The content of all free amino acids in fasting Artemia nauplii was lower than in the freshwater zooplankters. The major free amino acids in nauplii were 0.55% proline, 0.41% alanine, 0.34% glycine and 0.37% serine. The content of most free amino acids in nauplii decreased during fasting. The significance of the results are discussed in relation to essential amino acid requirements of fish, and nutrition of fish larvae without fully developed gastrointestinal systems.  相似文献   

160.
Climate change towards a warmer and dryer vegetation period may negatively impact growing conditions for Scots pine monocultures situated on dry, sandy soils in Central Europe. The purpose of the study was to evaluate the effect of thinning on precipitation throughfall in young Scots pine stands on typical pine sites. In 1992, observation of precipitation and throughfall started at the Tyniště research site (lowland of Eastern Bohemia) in a 7-year-old pine stand planted in rows at a stocking of ca 10,000 trees ha−1. Throughfall was measured at weekly intervals during the growing season (April-September) by gauges randomly located in two treatments - variant 1C - Control without thinning and variant 2T - Thinned - and compared to precipitation at an open space outside of the canopy. The results demonstrated the positive effects of heavy low thinning (removal of 47% of the total number of trees and 31% of total pre-treatment basal area) on the water supply of young Scots pine stands. On the Thinned treatment, throughfall increased by 2-8% compared to Control plot. This positive effect persisted for six years after the first canopy reduction and the differences were significant for the first four years after thinning. After the second treatment (high thinning), throughfall on the Thinned treatment showed a nominal, but statistically insignificant increase. The likely reason for this result is that the application of a different type of thinning increased the variability of the canopy and, consequently, the effect of released crowns could not be detected.  相似文献   
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