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61.
Methane emission by Nellore cattle subjected to different nutritional plans   总被引:1,自引:1,他引:0  
The objective was to evaluate the emission of enteric methane by Nellore cattle subjected to different nutritional plans, as well as the intake and digestibility of nutrients from the diets supplied. Forty-seven animals in a confinement system (feedlot) were fed a corn silage-based diet for 35 days. Afterwards, these animals were evaluated in a grazing system during the rainy periods, in Urochloa brizantha cv Marandu paddocks, for 44 days. Chromic oxide was used as external marker to estimate the fecal production of animals. Samples of feces, ingredients, and pasture were collected and sampled for subsequent chemical analyses. The SF6 tracer gas technique was adopted to quantify the methane gas emitted by the animals. The experimental design was completely randomized, using procedure GLM of software SAS (9.2), including the fixed effects of sex and nutritional plan and the linear effect of the co-variable weights. Means were analyzed by Tukey’s test at 5 % probability. The intakes of total dry matter and organic matter were greater for the animals subjected to the feedlot diet (P?P?P?4/day (104.01 g) by the animals fed the feedlot diet (P?4/CEB) and methane emission per dry matter consumed were lower in relation to the grazing treatment (3.75 vs 4.23 % and 11.67 vs 15.71 g/kg). The better quality of the diet in the feedlot promoted lower energy losses as methane.  相似文献   
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Ripening affects the quality and nutritional contents of fleshy fruits, and papayas are climacteric fruits very susceptible to postharvest losses due to the fast softening caused by ethylene. This paper reports the changes in respiration, ethylene production, and pulp color and firmness, along with the contents of soluble sugars and major carotenoids, during ripening of 'Golden' papaya, an important Brazilian cultivar that has been exported to North American and European markets. The results obtained for nontreated and ethylene- or 1-MCP-treated papaya suggest that 1-MCP can decrease the quality of treated fruit and that even the use of ethylene for triggering or inducing homogeneous ripening can result in lower quality when compared to that of fruit allowed to ripe naturally.  相似文献   
64.
The seroprevalence of caprine arthritis–encephalitis virus (CAEV) in the Cariri Region of Paraíba State, Brazil, was determined in 60 goat herds using the agar gel immunodiffusion test. The overall seroprevalence was 8.2%, with seropositivity in 21/60 (35%) herds and 13/15 (86.6%) municipalities. Bucks had a significantly higher frequency of infection (28.3%) than does (5.9%), and bucks that originated in other states had a significantly higher frequency of infection (76.5%) than those from Paraíba State (9.3%).  相似文献   
65.
The ripening mutant allele alcobaça (alc/alc) may be deployed to extend shelf life in tomatoes, but has reportedly negative effects on fruit colour development. Colour enhancing mutants crimson (og c /og c) and high pigment (hp/hp) could potentially overcome this limitation, but a detailed account of their interactions with alc is not available. In this paper, we report on intra-allelic (additive and dominant) interactions within these 3 loci, and on their possible interallelic (epistatic) interactions. Eight near-isogenic (NIL) tomato lines in background Flora-Dade were obtained, representing all possible 2nhomozygous combinations in the n = 3 loci. The 8 NIL were crossed in all possible combinations (reciprocals excluded), to obtain 28 hybrids that were heterozygous in at least one locus. The 36 treatments (= 8NIL + 28 hybrids) were grown in a randomized complete block design with 4replications, and the following traits were evaluated: total yield, average fruit mass, fruit firmness at harvest (= breakerstage) and 6 days after harvest (d.a.h)., % coloured fruit surface, fruit lycopene and beta-carotene contents, fruit % soluble solids and solids/acidity ratio, internal and external fruit colour. The loci alcobaça, crimson and high pigment or their epistatic interactions had significant influence on the expression of all traits measured. Epistatic effects were responsible for most of the variation among genotypes (with a minimum of 48.1%of the total sum of squares for % coloured fruit surface and a maximum of 82.8% for total yield). External fruit colour was defficient in all alc/alc genotypes, and their commercial use is impaired, in spite of improvements in fruit internal and external colour brought about by deployment of specific genotypic constitutions in lociog c and hp. Some but not all alc + /alc genotypes were firmer and showed improved fruit quality over the normal Flora-Dade (alc + /alc + og c+ /og c+ hp + /hp +) background. The following genotypic combinations represented good compromises between yield, long shelf life and fruit quality traits: alc + /alc og c+ /og c hp + /hp, alc + /alc og c /og c hp + /hp + and alc +/alc og c+/og c+ hp + /hp  相似文献   
66.
This study investigates the influence of fragment size on tree species composition, species richness and on individual groups of species within 11 semideciduous forest fragments in southeastern Brazil. We compared same-sized samples of 500 trees from 10 fragments <100 ha, allocated to three size categories, with three 500-tree samples collected in different areas within a large forest, used as a reference forest. The variation in species richness, in the proportion of species/individuals in dispersal modes, and in the proportion of rare species was not related to fragment size. Nonetheless, comparisons between the mean values of these variables of each fragment size categories, using 95% confidence intervals, showed a wider range of variation within the category of small-sized fragments than in the other size categories. NMS ordination plot also suggested the absence of a relationship between fragment area and tree species composition. However, multiple regressions using the scores from the NMS ordination as response variables, and area and disturbance intensities as predictor variables, suggested that the interaction of area and disturbance might be a good predictor of species composition. Pre-existing environmental heterogeneity and geographical proximity also appeared to play a role in the variations of forest composition among the fragments studied. Our results demonstrated the high conservation value of small forest fragments.  相似文献   
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68.

This study was performed with the main objective of evaluating the effect of the combination of pelleting and monensin on fatty acids (FA) composition, the concentration of total polyphenols and flavonoids, and the oxidative stability of milk in cows fed a concentrate containing soybean seeds. Eight Holstein multiparous cows were distributed in a replicated Latin square design. The four supplement treatments consisted of the combination of two factors (pelleting and monensin) and one concentrate as follows: (1) unpelleted concentrate with no monensin (CO); (2) pelleted concentrate with no monensin (PE); (3) unpelleted concentrate with 96 mg of monensin/kg of dry matter, DM (MO); and (4) pelleted concentrate with 96 mg of monensin/kg of DM (PM). There was no interaction between pelleting and monensin for milk production and concentration of milk protein, lactose, total polyphenols, flavonoids, conjugated dienes (CD), and reducing power. Fat and total solids concentration in milk were decreased when cows were fed pelleted (PE and PM) concentrates. Feeding cows with PE and PM concentrates increased the CD concentration in milk. Regarding milk FA concentration, there was no difference among treatments for total saturated, monounsaturated, and polyunsaturated FA. The most prominent result was that pelleting increased the milk concentration of omega-3 FA. Altogether, the present study suggests that the pelleting process can improve the milk fat quality by increasing the omega-3 FA, while the combination of pelleting and monensin in the diet of grazing dairy cows fed soybean-based concentrate adds no further improvements to FA profiles and oxidative stability of milk.

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69.
A 3-month-old foal with a history of acute hematuria was evaluated. Hydronephrosis and hydroureter were visualized upon renal ultrasonography of the left kidney. Cystoscopy identified a blood clot occluding the left ureter. Computed tomography (CT) revealed a large retroperitoneal abscess at the level of the aortic bifurcation and a left internal iliac aneurysm. Due to the severity of the lesions and the poor prognosis, the filly was euthanized and the clinical findings were confirmed by post-mortem examination. This report emphasizes the value of obtaining a precise diagnosis via CT in order to avoid unviable treatment approaches when confronted with this unusual secondary complication of omphaloarteritis.Key clinical message:Umbilical complications are routinely diagnosed in equine neonatal medicine, and commonly lead to septicemia, physitis, and septic arthritis; severe internal umbilical abscessation, and subsequent vascular and urinary disorders are uncommon sequelae.  相似文献   
70.
Superficial digital flexor tendon lesion is an important cause of lameness in equine athletes. Although numerous treatments have been described, few are effective at promoting significant improvement in the quality of the extracellular matrix. Therefore, great potential remains for recurrence and in certain cases, an abrupt end to the horse’s athletic career. Recently, several experiments have focused on the therapeutic potential of mesenchymal stem cells (MSCs) in cases of tendon lesions. This study aimed to evaluate the effect of adipose tissue-derived MSCs in the treatment of induced tendinitis of the superficial digital flexor tendon in horses by clinical, ultrasonographic, histopathological, and immunochemical analyses. Tendinitis was induced in both thoracic limbs of eight mares by administration of collagenase solution and adipose tissue was collected from the tail base for MSCs isolation and expansion, which were used during cellular therapy on only one limb 30 days after lesion induction. No differences occurred between the groups regarding the clinical and ultrasonographic analyses; however, histopathological evaluation revealed a significant improvement in tendon fiber organization and diminished inflammatory infiltrate, whereas immunohistochemical analysis showed increased expression of type I collagen in the treated group as compared with controls. The cellular therapy model implanted in this experiment promoted increased perivascular inflammatory infiltrate, fibroblastic density, neovascularization, and qualitative healing improvement of tendon extracellular matrix, in terms of fiber orientation and type I/III collagen ratio; moreover, it was considered to be a safe and viable process.  相似文献   
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