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121.
Variability in the availability of suitable prey (mainly nauplii stages of Calanus spp.) in the early life stages of cod is likely a significant contributor to the fluctuations in the year‐class strength in the Arcto Norwegian cod stock. We have investigated the origin of the Lofoten shelf population of Calanus using a particle tracking model approach based on velocity fields simulated from 2002 to 2012. By performing backwards simulations of trajectories from particles released on the Lofoten shelf in early spring, we assessed the relative contribution of potential Calanus sources, such as the Lofoten Basin, the local overwintering on the continental shelf and the adjacent fjords. This analysis revealed significant interannual differences in advection patterns mainly driven by changes in wind conditions and variable strength of the Norwegian Coastal Current. Most of the particles advected into our study area originated on the shelf, and contrary to expectations, only a few originated from the Lofoten Basin where Calanus abundances tend to be high. These results suggest that contribution from the Lofoten Basin to the early spring shelf Calanus population may be overestimated and that contribution from more local sources, especially from adjacent fjords, may play a more important role than what has been previously anticipated. Our results highlight the necessity to improve quantification of shelf‐fjord exchange processes, as these may contribute more to the regulation of spring zooplankton stocks on the northern Norwegian shelf, and, as a result, may affect the survival of cod larvae in this area.  相似文献   
122.
The success or failure of an investment project in fruit production also depends on the selection of the fruit species and variety. When selecting the variety for the creation of a new orchard it is necessary to perform the synthesis of different data and to look at all aspects of the investment. This paper presents the application of DEX multi-criteria decision making. The model was applied on 7 varieties of plum from the western Balkans region that were assessed by experts from “The association of agricultural economists of Western Balkans” using the Delphi method.By applying this model it has been shown that the ’Stanley’ is the most suitable for starting a new orchard while the varieties ’?a?anska ljepotica’ and ’?a?anska rodna’ are also very suitable for starting new fruit orchards and they have also received the value attribute “very acceptable”.Using this model all strong and weak sides of the observed plum variety were shown. For the final selection it is necessary to conduct research at a specific micro location where all characteristics of that area would also be taken into consideration.  相似文献   
123.
Global patterns of predator diversity in the open oceans   总被引:1,自引:0,他引:1  
The open oceans comprise most of the biosphere, yet patterns and trends of species diversity there are enigmatic. Here, we derive worldwide patterns of tuna and billfish diversity over the past 50 years, revealing distinct subtropical "hotspots" that appeared to hold generally for other predators and zooplankton. Diversity was positively correlated with thermal fronts and dissolved oxygen and a nonlinear function of temperature (approximately 25 degrees C optimum). Diversity declined between 10 and 50% in all oceans, a trend that coincided with increased fishing pressure, superimposed on strong El Ni?o-Southern Oscillation-driven variability across the Pacific. We conclude that predator diversity shows a predictable yet eroding pattern signaling ecosystem-wide changes linked to climate and fishing.  相似文献   
124.
125.
Inflammatory reactions are part of a complex biological response that plays a vital role in the appearance of various stimuli resulting from tissue and cell damage, the invasion of pathogenic bacteria, and the formation of the subsequent adaptive immune response. The production of many triggers and mediators of inflammation, which are inducers of pro-inflammatory factors, is controlled by numerous differentiation programs, through which inflammation is resolved and tissue homeostasis is restored. However, prolonged inflammatory responses or dysregulation of pro-inflammatory mechanisms can lead to chronic inflammation. Modern advances in biotechnology have made it possible to characterize the anti-inflammatory activity of phlorotannins, polyphenolic compounds from brown seaweed, and the mechanisms by which they modulate the inflammatory response. The purpose of this review is to analyze and summarize the results of numerous experimental in vitro and in vivo studies, illustrating the regulatory mechanisms of these compounds, which have a wide range of biological effects on the body. The results of these studies and the need for further research are discussed.  相似文献   
126.
The molecular karyotype of Paranosema grylli Sokolova, Seleznev, Dolgikh et Issi, 1994, a monomorphic diplokaryotic microsporidium, comprises numerous bright and faint bands of nonstoichiometric staining intensity. Restriction analysis of chromosomal DNAs by "karyotype and restriction display" 2-D PFGE has demonstrated that the complexity of molecular karyotype of P. grylli is related to the pronounced length polymorphism of-homologous chromosomes. The background of this phenomenon is discussed in the context of ploidy state, reproductive strategy and population structure in this microsporidium. We propose that the remarkable size variation between homologous chromosomes in P. grylli may be a consequence of ectopic recombination at the chromosome extremities.  相似文献   
127.
SUMMARY: Lactation records, collected from 1989 to 1995, for Belgian dairy goats were examined for effects of parity, breed, herd-year, age at kidding, and month of kidding on milk, fat and protein yields, and on fat and protein percentages. Total lactation yields were computed from test-day yields, using Fleischmann's method. For lactations longer than 250 days, yields were truncated at 250 days. Partial lactations (25 days minimum) were extended to 250 days, and fat and protein percentages were deducted from the yields. After editing a total of 2997 lactation records of 2562 does remained. The parity classifications were first and second or greater; kidding seasons were defined as December, January, February, March, April to July, and August to November. The breed groups were Anglo-Nubian, Chamoisee, Saanen, and crossbreeds. The data were analysed within parity with a fixed-effect model that included effects of herd-year, breed, month of kidding, and age at Kidding. All effects in the model were significant on the traits measured for parities, except the age effects on fat percentage and of month of kidding on protein percentage at first parity. Saanen had the highest milk yield at first parity; at later parities, the Chamoisee produced most. Yield increases were large between first and later parities. Does freshening in February produced more milk than those that freshened at other months. Monthly variations in fat and protein percentages across parities, although mostly significant, were small. Yields increased with age at first parity; for later parities, they increased until 25-30 months for milk and until 40 months for fat and protein, and then decreased. Fat and protein percentages increased up to 15-17 months of age, and then decreased to the lowest values around 25 months; this was followed by an increase around 32 months, which tended to stabilize until 50 months. The ranges of R(2) associated with effects were: for herd-year, 43-52% and 22-36%; for breed, 3-11% and 4-12%; for month of kidding 6-10% and 2-5%; for age at kidding 3-7% and 1-17%-for first and second, and later parities, respectively. RéSUMé: L'influence des effets numéro de lactation, race, troupeau-année, mois et age à la mise bas a été étudiée sur la production des chèvres laitières de Belgique, enregistrées de 1989 à 1995. Les productions totales réalisées ont été calculées à partir des résultats aux contr?les. Pour les lactations supérieures à 250 j, les productions ont été tronquées à 250 j. Les lactations partielles (minimum 25 j) ont été extrapolées à 250 j. Au total, 2997 lactations à 250 jours étaient disponibles, pour 2562 chèvres des races Anglo-nubienne, Chamoisée, Saanen et croisées. Les données ont été réparties en 2 parités (1 et ≥ 2), 6 mois de mise bas (décembre, janvier, février, mars, avril à juillet et ao?t à novembre). Le modèle d'analyse intra-parité comprenait les effets fixes troupeau-année, race, mois et age à la mise bas. Tous les effets ont été significatifs sur les paramètres étudiès à l'exception de l'effet de l'age sur les taux de matière grasse et de l'effet du mois de mise bas sur les taux de protéine, en parité 1. En première lactation, les Saanen ont enregistré les plus hautes productions de lait tandis qu'en seconde lactation, ce furent les Chamoisées. L'accroissement des productions a été important entre première et seconde lactation. Les mises bas de février ont enregistré les productions les plus élevées. Les taux de matières grasse et protéique ont accusé de faibles variations saisonnières. A l'exception de la parité 1 oú elles augmentaient, les productions de lait, matière grasse et protéine tendaient à diminuer avec l'age. Une diminution des taux avec l'age a été observée. Les données ont permis d'établir de nettes différences de production entre la première et la seconde parité à ages identiques; cependant leur nombre encore limité n'a pas permis d'apprécier les effets d'intéractions age × parité, age × mois de mise bas on troupeau-année × mois de mise bas. Les valeurs de R(2) associées aux effets ont été: pour troupeau-année 43 à 52% et 22 à 36%, pour race 3 à 11% et 4 à 12%, pour mois de mise bas 6 à 10% et 2 à 5%, et pour l'age à la mise bas 3 à 7% et 1 à 17%, respectivement pour les primipares et les multipares. ZUSAMMENFASSUNG: Einfluss von Laktationsnummer, Rasse, Herde-Jahr, Wurfmonat und -jahr auf Milch-, Fett- und Proteinertag und Fett- und Milchprozente bei belgischen Milchziegen Die Gesamtlaktationsleistungen wurden aus den Stichtagsleistungen mit der Methode von Fleischmann berechnet. Laktationsleistungen von mehr als 250 Tagen Dauer wurden auf 250 Tage standardisiert, Teillaktationen (Minimum 25 Tage) auf 250 Tage extrapoliert und Fett- und Proteingehalte aus den Leistungen abgeleitet. Von 2562 Ziegen der Rassen Anglo-Nubier, Gemsfarbige Gebirgsziege, Saanen sowie Kreuzungen standen Daten von 2997 Laktationen zu 250 Tagen zur Verfügung. Die Daten wurden in erste und folgende Laktationen sowie nach Wurfmonat (Dezember, Januar, Februar, M?rz, April bis Juli, August bis November) gruppiert. Die Analyse der Daten wurde mit einem Modell fixer Effekte vorgenommen, das Herde-Jahr, Rasse, Wurfmonat und- alter beinhaltete. Ausser den Effekten des Wurfalters auf Fettprozente und des Wurfmonats auf Proteinprozente in der ersten Laktation waren alle untersuchten Parameter signifikant. In der ersten Laktation erzielten die Saanenziegen, in den folgenden Laktationen die Gemsfarbigen die h?chste Milchleistung. Zwischen der ersten und den folgenden Laktationen stieg die Milchleistung stark an. Würfe im Februar verzeichneten die h?chste Milchleistung. Monatliche Variationen in Fett- und Proteinprozenten über alle Laktationen waren zwar meist signifikant, aber von geringem Ausmass. Die Leistungen erh?hten sich in der ersten Laktation mit steigendem Alter. In den folgenden Laktationen stiegen die Milchleistung bis zum Alter von 25 bis 30 Monaten und die Fett- und Proteinertr?ge bis 40 Monate; danach nahmen die Leistungen ab. Fett- und Proteinprozente erh?hten sich bis zu einem Alter von 15 bis 17 Monaten und nahmen dann ab, um bei 25 Monaten die tiefsten Werte zu erreichen. In der Folge nahmen die Werte ab 32 Monaten wieder zu, um sich bei 50 Monaten zu stabilisieren. Die Bereiche der R(2) der verschiedenen Effekte lagen für Herde-Jahr bei 43 bis 52%, die Rasse bei 3 bis 11%, den Wurfmonat bei 6 bis 10% bzw. 2 bis 5% (erste und folgende Laktationen) und das Wurfalter bei 3 bis 7% bzw, 1 bis 17%.  相似文献   
128.
1. The objective was to investigate the effect of cage height on perch height preference and perching behaviour in laying hens. Twelve groups of two hens and 12 groups of 14 hens were tested in furnished cages equipped with two wooden perches. These stepwise perches were designed such that hens could choose between 7 different heights (6, 11, 16, 21, 26, 31 and 36 cm). Day- and night-time perching behaviour was observed on 4 consecutive days with a different cage height each day: 150, 55, 50 and 45 cm. 2. Given that a minimum perch-roof distance of 19 to 24 cm was available, hens preferred to roost on the highest perches at night. 3. Lowering cage height not only forced hens to use lower perches, but also reduced time spent on the perches during the day (two-hen and 14-hen test) and night (14-hen test). Moreover, it affected daytime behavioural activities (more standing and less preening) on the perches in the two-hen tests (but not in the 14-hen tests). 4. During the day lower perches were used more for standing and walking, higher perches more for sitting and sleeping. This behavioural differentiation was most pronounced in the highest cages. 5. Perch preference and perching behaviour depend on both the floor-perch distance and the perch-roof distance. Higher cages provide more opportunity for higher perches (which hens prefer), for better three-dimensional spacing (and consequently reduced density at floor level) and for behavioural differentiation according to perch height.  相似文献   
129.
Many proteins of the calcium-dependent (C-type) lectin family have been shown to play an important role in innate immunity. They can bind to a broad range of carbohydrates, which enables them to interact with ligands present on the surface of micro-organisms. We previously reported the finding of a new putative chicken lectin, which was predominantly localized to the respiratory tract, and thus termed chicken lung lectin (cLL). In order to investigate the biochemical and biophysical properties of cLL, the recombinant protein was expressed, affinity purified and characterized. Recombinant cLL was expressed as four differently sized peptides, which is most likely due to post-translational modification. Crosslinking of the protein led to the formation of two high-molecular weight products, indicating that cLL forms trimeric and possibly even multimeric subunits. cLL was shown to have lectin activity, preferentially binding to alpha-mannose in a calcium-dependent manner. Furthermore, cLL was shown to inhibit the haemagglutination-activity of human isolates of influenza A virus, subtype H3N2 and H1N1. These result show that cLL is a true C-type lectin with a very distinct sugar specificity, and that this chicken lectin could play an important role in innate immunity.  相似文献   
130.
Monitoring the locomotion and posture behaviour of pregnant cows close to calving is essential in determining if there is a need for human intervention to assist parturition. In this study an automatic real-time monitoring technique is described in detail which allows identifying the locomotion and posturing behaviour of pregnant cows prior to calving. For this purpose video surveillance images of eight cows for the last 24 h prior to their calving were analysed. Data on seven different variables with time were obtained for each cow using an automatic real-time monitor. These were namely: xy coordinates of the geometrical top view centre point of the cow; walking trajectory; distance walked; orientation of the main axis; body width/length ratio; hip length and back area. These variables were then used to classify specific behaviours such as standing or lying (including incidences of motion during lying), and eating or drinking. On average 85% of the standing and lying and 87% of the eating or drinking behaviour of the eight cows during the last 24 h before calving could be correctly classified. However, the developed technique needs to be further validated with additional tests in the field.  相似文献   
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