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71.
Objective To determine the normal aerobic bacterial conjunctival population of the Coatis and the Crab‐eating raccoons housed in captivity in the Pernambuco and Paraiba states of Brazil. Animals studied Ten healthy Coatis and 10 healthy Crab‐eating raccoons were selected for this study. Animals are from three zoos situated at the Pernambuco and Paraiba States in the north‐east of Brazil. Procedures After ophthalmologic examination, swabs from healthy animals were carefully collected in order to avoid contamination. Samples were identified and submitted to the laboratory. Swabs were plated for culture on ovine blood agar (8%) and agar Levine and incubated at 37 °C and observed 24 and 48 h. Results Staphylococcus spp. was the most common microorganism isolated from conjunctival sac. Shigella spp. comprised the Gram‐negative genera isolated. Escherichia coli were isolated from the right eye of one Coati that had no growth at contralateral eye. Nine eyes from coatis and 10 from Crab‐eating raccoons had no microorganisms isolated. Conclusion Our results were in accordance with previous studies indicating Staphylococcus sp., followed by Corynebacterium spp. as the most common inhabitant of the eyes of most mammalian species.  相似文献   
72.

We assessed the response of maize canopy arthropods to the insecticide chlorpyrifos. Four 0.3 ha (18 2 180 m) plots were divided into two subplots, a control and a treated area. During tasseling of the plants, the treated area was sprayed twice, with an interval of 3 days. Ten plants were sampled: 1 day before spraying, and 7, 14, 21 and 28 days after spraying. The insecticide had no effect on insect herbivores: a high density of Spodoptera frugiperda larvae was present in the treated plots. A few predator arthropod species were negatively affected by the insecticide, but their numbers or activity increased 2 weeks after the treatment of the plots. A canonical variate analysis showed no pronounced effect of the insecticide on arthropod communities; the largest variations on species abundance were related to sampling occasion. These results can be explained by the combination of the short period of chlorpyrifos residual activity on the plant surface and the great potential for recolonization of the areas by most of the monitored arthropods.  相似文献   
73.
74.
The effects of two levels of concentrate and ruminally undegradable protein (RUP) on performance, intake, digestibility, carcass characteristics, meat quality traits, and commercial cuts yield were assessed. Twenty crossbred heifers (240 kg average body weight) were used. At the beginning of the trial, four animals were slaughtered as reference group and the 16 remaining animals were randomly assigned to four treatments, in a 2 × 2 factorial design: two levels of concentrate (40% and 80%, dry matter (DM) basis) and two levels of RUP (48.79% and 27.19% of CP). At the end of the trial, all the animals were slaughtered. There was no interaction (P > 0.05) between concentrate and RUP levels. Dry matter intake and nutrients digestibility was not affected (P > 0.05) by RUP level. Heifers fed the highest RUP level had greater (P < 0.05) average daily gain (ADG). Concentrate level did not affect (P > 0.05) DMI and ADG. Heifers fed diets with 80% concentrate had greater intake of TDN and EE, and lower intake of NDF (P < 0.05). The digestibilities of all nutrients, except the NDF, were greater (P < 0.05) for the 80% concentrate diets. The RUP levels did not affect (P > 0.05) the carcass characteristics and carcass gain composition. Heifers fed 80% concentrate diets had larger (P < 0.05) longissimus muscle area and lower gain of bones (P < 0.05). Concentrate level did not affect (P > 0.05) the composition of carcass gain. There was no effect (P > 0.05) of RUP and concentrate levels on meat quality traits and commercial cut yields.  相似文献   
75.
The main pedological, geomorphological and cryogenic features of Keller Peninsula, part of Admiralty Bay, King George Island, Maritime Antarctica, were mapped and quantified with emphasis on the relationship between the ice retreat process, melt-out, landform development and soil distribution. Moraines, protalus, scree slopes, inactive glacial cirques, uplift marine terraces, biogenic landforms, arêtes and Felsenmeer were mapped. Scree slope is the main landform, covering approximately 25% of the peninsula, indicating prominent paraglacial features. Inherited, glacial landforms, such as lateral moraines, highland plateau and exhumed U shaped-valleys, are now being exposed in north Keller by ice shrinkage of former ice protecting cover. Landforms influenced soil formation and stability. Cryosols and Leptosols (WRB) roughly corresponding to Gelisols and Entisols (SSS), respectively, are the most common soil classes, with an overall tendency of absent permafrost in the coastal areas, changing to sporadic permafrost at mid-slope, and discontinuous permafrost with greater altitude and substrate stability.  相似文献   
76.
Selection for bulls that would reach puberty early reduces the generation interval and increases fertility and herd productivity. Despite its economic importance, there are few QTL associated with age at puberty described in the literature. In this study, a weighted single-step genome-wide association study was performed to detect genomic regions and putative candidate genes related to age at puberty in young Nelore bulls. Several protein-coding genes related to spermatogenesis functions were identified within the genomic regions that explain more than 0.5% of the additive genetic variance for age at puberty in Nelore bulls, such as ADAM11, BRCA1, CSNK2A, CREBBP, MEIOC, NDRG2, NECTIN3, PARP2, PARP9, PRSS21, RAD51C, RNASE4, SLX4, SPA17, TEX14, TIMP2 and TRIP13 gene. Enrichment analysis by DAVID also revealed several GO terms related to spermatogenesis such as DNA replication (GO:0006260), male meiosis I (GO:0007141), double-strand break repair (GO:0006302), base excision repair (GO:0006284), apoptotic process (GO:0006915), cell–cell adhesion (GO: 0098609) and focal adhesion (GO:0005925). The heritability for age at puberty shows that this trait can be improved based on traditional EBV selection. Adding genomic information to the system helps to elucidate genes and molecular mechanisms controlling the sexual precocity and could help to predict sexual precocity in Nelore bulls with greater accuracy at younger age, which would speed up the breeding programme for this breed.  相似文献   
77.
Nellore is the main cattle breed used in Brazil, being the largest commercial herd in the world. Beyond the importance of male reproductive efficiency for farm profit, the use of reproductive techniques, mainly artificial insemination, turns the evaluation of male reproductive traits even more important. Estimation of genetic parameters increases the knowledge on traits variances and allows envisaging the possibility of the inclusion of new traits as selection criterion. Genetic parameters for fifteen traits that can be classified as testicular biometry or physical and morphological semen traits were estimated for a Nellore bull population ranging from 18 to 36 months. Single-trait and bi-trait animal models were used for (co)variance components estimation. The contemporary group was considered as fixed effect and age at measurement as covariable. Scrotal circumference presented heritability of 0.47 ± 0.12. This value is similar to the heritabilities found for all testicular biometry traits (0.34–0.48). Sperm progressive motility, which has a direct effect on bull fertility, presented low heritability (0.07 ± 0.08). Major and total sperm defects presented moderate to high heritabilities (0.49 ± 0.18 and 0.39 ± 0.15, respectively), indicating that great genetic gain can be obtained through selection against sperm defects. High and positive genetic correlations were observed among testicular biometry traits, which also presented favourable genetic correlations with physical and morphological traits of the semen with magnitude ranging from high to low. Scrotal circumference presented moderate to high and favourable genetic correlations with sperm progressive motility, sperm turbulence, major sperm defects and total sperm defects. Thus, the selection for scrotal circumference results in favourable correlated genetic response for semen quality. The results show that the use of scrotal circumference as reference trait for bull fertility is appropriate, since it presents high heritability and favourable genetic correlation with semen quality.  相似文献   
78.
The use of reclaimed wastewater in agriculture can be a solution for regions with water shortages or low rainfall periods; besides fulfilling the crop's water needs, it would also promote the recycle of nutrients. However, care should be taken regarding soil salinization, especially in closed environments such as greenhouses for the cultivation of ornamental plants. The domestic effluents are rich in sodium which can accumulate on soil and cause soil sealing. This study evaluated the use of effluents from anaerobic filters and intermittent sand filters in the production of rosebushes (Rosa hybridaAmbiance”). The crop yield of the rosebushes irrigated with reclaimed wastewater exceeded the one obtained with traditional cultivation, reaching a value 31.8 % higher when employing nitrified effluent originated from intermittent sand filters, with no difference in the product quality. The salinity levels are below the critical limits found in the literature; however, there was a significant increase compared to the irrigation with drinking water.  相似文献   
79.
Three diagrammatic grading keys were designed for the assessment of the severity of late blight (caused by Phytophthora infestans ) in tomato leaves. Simplified and broad keys considered, respectively, six (3, 12, 22, 40, 60 and 77%) and eight (3, 6, 12, 22, 40, 60, 77 and 90%) levels of disease severity, whilst a modified key based on a previous proposal for potato late blight considered six levels (1, 5, 10, 16, 32 and 50%). The keys were validated by 24 evaluators who assessed digital images of tomato leaves exhibiting different areas with lesions. Evaluator errors were compared using a mixed model in which evaluators were considered as random effects and the keys and evaluations as fixed effects. The accuracy and precision of the evaluators were compared by simple linear regression between the estimated and actual values of disease severity. The repeatability of evaluators was assessed using Pearson's correlation coefficient. There was significant ( P  ≤   0·001) variability amongst the errors made by evaluators, although the precision of each of the three keys was high with a coefficient of determination (R2) of 0·96, 0·93 and 0·83 for the simplified, broad and modified key, respectively. Repeatability of estimations amongst the evaluators was adequate (correlation coefficients of 0·91, 0·91 and 0·90 for the three keys, respectively). The simplified and broad keys resulted in higher precision and accuracy for the estimation of severity than did the modified key. Since the simplified key considers a smaller number of disease severity levels, its use is recommended in the assessment of late blight in tomato leaves.  相似文献   
80.
ABSTRACT The genetic inheritance of resistance to leprosis, the most important viral disease of citrus in Brazil, was characterized through the phenotypic assessment of 143 hybrids resulting from crosses between tangor 'Murcott' (Citrus sinensis x C. reticulata) and sweet orange 'Pêra' (C. sinensis), considered to be resistant and susceptible to the disease, respectively. All plants were grafted onto Rangpur lime (C. limonia) and inoculated with Citrus leprosis virus, cytoplasmic type through the infestation with viruliferous mites, Brevipalpus phoenicis. The experiments were arranged in a completely randomized block design with 10 replicates. Incidence and severity of the disease in leaves and stems as well as plant growth parameters (plant height and stem diameter) were recorded for 3 years after the infestation with the viruliferous mites. The average values of all variables were analyzed using principal component analysis, discriminant factorial analysis, estimation of the clonal repeatability coefficients, and frequency of the distributions of the average values for each measured variable. The principal component analysis resulted in the identification of at least two groups with resistance and susceptibility to leprosis, respectively. About 99% of all hybrids were correctly classified according to the discriminant factorial analysis. The broad-sense heritability coefficients for characteristics associated with incidence and severity of leprosis ranged from 0.88 to 0.96. The data suggest that the inheritance of resistance to leprosis may be controlled by only a few genes.  相似文献   
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