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111.
Tropical Animal Health and Production - The objective of this study was to analyze the correlation between condemnations in slaughterhouses situated in Minas Gerais State and notifications to the...  相似文献   
112.
The neural system plays an important role in understanding some features of animals. Anatomical complexity correlates with the increase of functional capacity. Xenarthrans include anteaters (Vermilingua), armadillos (Cingulata) and sloths (Folivora). This group is the base of eutherian mammals, and understanding the anatomy of its neural system could provide data for functional and evolutionary interpretations. The gross anatomy of the xenarthran brain is recorded. Four extant families of Pilosa and two families of Cingulata were sampled. Usual dissection procedures were used, and the brains were analysed macroscopically. The brain of two-toed sloth, three-toed sloth, six-banded armadillo, giant anteater and collared anteater are gyrencephalic. Pygmy anteater, nine-banded armadillo, great long-nosed armadillo, southern naked-tailed armadillo and giant armadillo are lissencephalic. In most species, the rhinal fissure presents two segments, rostral and caudal (except in Vermilingua and three-toed sloth). The diencephalon and brainstem present similar anatomy. The cerebellum is wide and presents four lobes (rostral, central, caudal and floccular). Its average volume is 12.16% (Folivora), 14.26% (Vermilingua) and 18.61% (Cingulata). Among these groups, there is a statistical difference between Folivora/Cingulata concerning the cerebellum average. The general pattern of the brain of the xenarthrans is similar to that of other mammals.  相似文献   
113.
The effect of aluminum (Al) ions on the germination of wheat (Triticum aestivum L.) seeds has been investigated using two varieties, one sensitive to Al (Robin) and the other relatively Al‐tolerant (Carazinho). High concentrations of Al (i.e. greater than 1 mM) were required to inhibit the growth of the emerging roots and shoots of germinating seeds of both varieties. Moreover, Al at concentrations up to 10 mM did not affect the mobilization of carbohydrate reserves in the germinating seeds. It was concluded that germinating seeds of both wheat varieties were much less sensitive to the effects of Al than were established seedlings.  相似文献   
114.
The effects of nitrogen (N‐) and phosphorus (P‐) deficiency, isolatedly or in combination, on growth, nitrogenous fraction, and inorganic phosphate in xylem exudade, and photosynthesis of common bean (Phaseolus vulgaris L. cv. Negrito) were investigated. Plants were grown in nutrient solution adjusted daily to pH 5.5 and aerated continuously. Ten days after emergence mineral deficiency was imposed. Plants were then supplied with high N (7.5 mol m‐3) or low N (0.5 mol m‐3), and also with high P (0.5 mol m‐3) or low P (0.005 mol m‐3). All sampling and measurements were made 28 days after emergence. N‐ or P‐deprivation brought about large decreases in total leaf area by inhibiting the emergence of new leaves and primarily the expansion of the leaves. The specific leaf area did not change under N‐ but decreased under P‐limitation. The decreased shoot to root ratio in all deficiency treatments was a consequence of a lowering mass of above‐ground organs, especially of leaves.

The content of chlorophylls declined significantly only under N‐deficiency alone; carotenoids declined under both N‐ and combined N‐ and P‐limitation. No alteration in amino acid concentration in xylem exudate occurred in plants experiencing N‐starvation, while ureides increased by 79%, and nitrate and inorganic phosphate decreased greatly. Under P‐deprivation, amino acids and nitrate in xylem sap dropped by about half; ureides were held relatively constant, and phosphate was severely depressed. Total upward translocation of N through xylem was estimated to be about 16% higher in N‐deficient plants than in plants without mineral limitation, but leaf N levels in the former were lower as compared to control plants. The net carbon (C) assimilation decreased similarly regardless of the imposed deficiency treatment. Such a decrease was mainly determined by non‐stomatal factors. In general, no additive effect between N‐ and P‐limitation on any of measured parameters was observed.  相似文献   
115.
Phytoparasitica - The current agricultural scenario faces a range of challenges, with phytosanitary ones being paramount. In most cases, plant diseases are treated with chemicals; however, they...  相似文献   
116.
Journal of Plant Diseases and Protection - The recent use of essential oils has been considered an important approach in pest management programs for stored products. Regarding essential oils, it...  相似文献   
117.
European Journal of Plant Pathology - This study aimed to evaluate the potential antagonistic role of Trichoderma in the control of Fusarium isolates belonging to the Fusarium oxysporum species...  相似文献   
118.
European Journal of Plant Pathology - Apple valsa canker, caused by the fungus Valsa ceratosperma, is one of the most destructive diseases of this crop. Conventional fungicide treatments are not...  相似文献   
119.
120.
Real time computer stress monitoring of piglets using vocalization analysis   总被引:2,自引:0,他引:2  
The analysis of animal vocalization allows the interpretation of stress pattern in a non-invasive way, and it may be used to assess welfare as well as health status and social adaptation. This paper presents the development of software to monitor and analyze distinct sounds emitted by piglets correlating the noise response with levels of stress for assessing welfare. The software was developed using Delphi5. Through the component UwaveIn the sound was recorded with an electronic microphone and set to a PC hardware that registered the signal of amplitude noise intensity, expressed in decibel (dB), converting them into bytes. Fourier Transform was used to describe the sound spectrum and transform it into frequency and intensity. Validation of the software was done in a commercial swine farm using piglets from sows’ nursery. Five examples of vocalization were studied related to distinct levels of stress (fear and alertness) due to regular management procedures. The real time monitoring allowed the detection of piglet stress exposure through the surface point polynomial adjustment. The acoustic signal recorded in the software could be partitioned allowing an evaluation of the sonograph through time.  相似文献   
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