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481.
The effect of crate height on the behavior of female turkeys during commercial pre‐slaughter transportation
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Guido Di Martino Katia Capello Anna Lisa Stefani Luca Tripepi Angelica Garbo Marina Speri Matteo Trolese Michele Brichese Stefano Marangon Lebana Bonfanti 《Animal Science Journal》2017,88(10):1651-1657
Limited information is available on suitable height of transport crates for turkeys. We compared behaviors and physiological indicators of four groups of 10 female turkeys each confined in either conventional (38.5 cm height) or experimental (77 cm height) crates during six commercial pre‐slaughter transportations for 86 km (76 ± 4 min) along two tracts with one‐lane streets, crossroads, bends, roundabouts (S1 and S2) and a highway tract (H) between S1 and S2. Only 36% of birds in the higher crates maintained a standing position. In conventional versus experimental crates, the frequency of rising attempts was five/bird/hour versus less than one/bird/hour, while wing flapping was seven/bird/hour versus 20/bird/hour, and balance loss was one versus four/bird/hour. The behaviors of both groups differed significantly according to the route tract, with a lower frequency of stress‐related behaviors at H. No scratches, fractures or hematomas were detected in any birds after transportation. Crate height had no significant effect on hemato‐biochemical markers. These results suggest that crates enabling a standing position may increase potentially dangerous behaviors. Moreover, busy and curvy routes should be avoided, as they may contribute to increasing the frequency of stress‐related behaviors. 相似文献
482.
Angela R. Piergiovanni Domenico Cerbino Michele Brandi 《Genetic Resources and Crop Evolution》2000,47(5):489-495
The variation within a collection constituted by 36 populations of common bean (Phaseolus vulgarisL.) recently collected in Basilicata region (Southern Italy) was studied. These populations are cultivated in marginal areas of the region mainly for farms' self-consumption. An appreciable variation of seed shape, colour and type of pattern was observed; 34 populations are of climbing growth habit. The frequency of the phaseolin types within the collection was investigated. C, T and S phaseolin types were observed, the type C being predominant (18 of 36 landraces); intra-population variation was detected only for two landraces. Local populations were compared with 28 commercial cultivars widely grown in the Basilicata region and accounting for 80–90% of common bean production. Significant divergences in growth habit and frequency of phaseolin types were observed: 22 cultivars had bush growth habit and 20 showed T phaseolin type. These results stress the urgency of actions devoted to the safeguard of this local germplasm. In fact, the diffusion of alloctonous and not typical germplasm is the first step towards the erosion of useful or valuable genes present in those established local populations. 相似文献
483.
Andrea Mainetti Simone Ravetto Enri Marco Pittarello Giampiero Lombardi Michele Lonati 《Grass and Forage Science》2023,78(2):254-267
Summer pastures in the European Alps play a crucial role in providing high quality forage for grazing livestock and encompass a wide variety of vegetation communities. The main issue of their management is the optimal exploitation of the available forage in relation to environmental constraints, aiming at obtaining the highest forage yield and quality from each vegetation community. In this work, we monitored six different vegetation communities characterized by contrasting topographic features and species compositions throughout the grazing season for two years. We performed botanical and phenological surveys, climate-related measurements, and herbage samplings to assess forage quantity and quality (i.e., digestibility and proximate composition, estimated by near-infrared reflectance spectroscopy). We analysed the influence of climatic, topographic, and vegetation variables on pasture herbage through univariate and multivariate analyses. The cover of wide-leaf grasses primarily promoted biomass production, which was in turn lowered by increasing elevation and slope. On the other hand, a minor effect on forage yield was observed for an increasing cover of sedges and rushes and mean temperatures. Climatic variables (especially water deficit) and advanced phenological stages were the main degrading factors of forage quality in terms of crude protein and digestibility, while enhancing fibre contents. At increasing cover of legumes, fibre content declined and digestibility increased consequently, while the abundance of other non-legume forbs played a significant role in lowering fibre content. Multivariate analysis highlighted the differing influence of single plant species on forage features even within the same functional species pool. However, attention should be paid to the toxicity and low palatability of some plants, especially forbs. Eutrophic vegetation communities, rich in wide-leaf grasses and legumes, could be maintained and enhanced through pastoral management to increase alpine pasture production and quality. 相似文献
484.
Ariane Furtado de Lima Maristela Cavicchioli Makrakis Fernanda Freitas Andrade Elaine Antoniassi Luiz Kashiwaqui Michele de Faveri Gimenes Sergio Makrakis 《Aquaculture Research》2017,48(4):1618-1628
The feeding selectivity of laboratory‐reared larvae of Rhamdia voulezi was assessed to investigate the preferred preys in early life stages. Three experiments were conducted at different larval development stages, starting soon after the absorption of the yolk sac (on fourth day after hatching – DAH), using zooplankton from fish ponds as food. Differences were detected in the patterns of prey selection among development stages. At first, the larvae prefer small preys, such as rotifers and cladocerans. Later, when they are more developed, they prefer to feed on large preys, such as copepods. On the fourth DAH, larvae in the pre‐flexion and initial flexion stage strongly selected rotifers and cladocerans (Diaphanosoma spinulosum, D. brevireme, Moina sp., M. micrura and M. minuta). At the other stages, cladocerans continued to be strongly selected. However, on the eighth DAH, larvae in flexion stage selected less strongly copepods Argyrodiaptomus azevedoi, Metacyclops mendocinus and Termocyclops decipiens. On the tenth DAH, larvae in postflexion stage selected more strongly copepods Argyrodiaptomus furcatus, Notodiaptomus cf. spinuliferus and M. mendocinus. As larvae grow, they tend to specialize in feeding of a particular prey. Prey selection of R. voulezi larvae was based both on species and zooplankton size. The size of the zooplankton ingested was related to the mouth gape size of larvae. 相似文献
485.
486.
Da Silva Pinto M Bouhallab S De Carvalho AF Henry G Putaux JL Leonil J 《Journal of agricultural and food chemistry》2012,60(1):214-219
The behavior of β-lactoglobulin (β-Lg) during heat treatments depends on the environmental conditions. The influence of the presence or absence of a reducing sugar, namely, glucose, on the modification of the protein during heating has been studied using fluorescence, polyacrylamide gel electrophoresis (PAGE), size-exclusion chromatography (SEC), and transmission electron microscopy. Glycated products were formed during heating 24 h at 90 °C and pH 7. The fluorescence results revealed an accumulation of the advanced Maillard products and the formation of aggregates during heating. PAGE and SEC data suggested that the products in the control samples were essentially composed of covalently linked fibrillar aggregates and that their formation was faster than that for glycated samples. We showed that glucose affected the growing step of covalent aggregates but not the initial denaturation/aggregation step of native protein. Glucose-modified proteins formed a mixture of short fibrils and polydisperse aggregates. Our results revealed that β-Lg forms fibrils at neutral pH after heating and that glucose slows the formation of these fibrils. 相似文献
487.
Laura Giagnoni Francesca Magherini Loretta Landi Safiyh Taghavi Daniel van der Lelie Michele Puglia Laura Bianchi Luca Bini Paolo Nannipieri Giancarlo Renella Alessandra Modesti 《Biology and Fertility of Soils》2012,48(4):425-433
Cupriavidus metallidurans CH34 is a completely sequenced soil-borne beta-proteobacterium with known genome and proteome. Comparative 2-D electrophoresis and protein mass spectrometry were used to compare the proteome of C. metallidurans CH34 from liquid culture and after incubation for 1, 3, and 12?days in microcosms containing quartz sand, kaolinite, montmorillonite, or an artificial soil. Results showed that proteome from liquid culture was similar to CH34 proteins extracted from sand and kaolinite, whereas the proteins extracted from artificial soil differed significantly and no proteins were detected from C. metallidurans CH34 incubated in the montmorillonite microcosms. Protein recovery decreased on prolonging incubation time in all microcosms. Mass spectrometry identification showed that the trend of lower recovery upon incubation time was independent on the putative function of protein. These results suggest that the soil solid phase influences the protein recovery and soil proteomic analysis and that distinction between protein recovery and protein expression in soil will be a challenging for soil proteomic researchers. 相似文献
488.
The genome sequence of the malaria mosquito Anopheles gambiae 总被引:2,自引:0,他引:2
Holt RA Subramanian GM Halpern A Sutton GG Charlab R Nusskern DR Wincker P Clark AG Ribeiro JM Wides R Salzberg SL Loftus B Yandell M Majoros WH Rusch DB Lai Z Kraft CL Abril JF Anthouard V Arensburger P Atkinson PW Baden H de Berardinis V Baldwin D Benes V Biedler J Blass C Bolanos R Boscus D Barnstead M Cai S Center A Chaturverdi K Christophides GK Chrystal MA Clamp M Cravchik A Curwen V Dana A Delcher A Dew I Evans CA Flanigan M Grundschober-Freimoser A Friedli L Gu Z Guan P Guigo R 《Science (New York, N.Y.)》2002,298(5591):129-149