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1.
Serum samples from 37 captive exotic felids in 12 zoos from six Brazilian states were assayed for antibodies to Toxoplasma gondii by the modified agglutination test using formalin-fixed whole tachyzoites. Titers greater than or equal to 1:20 were considered positive. Antibodies to T. gondii were found in 24 of 37 (64.9%) felids, including one European lynx (Lynx lynx), two jungle cats (Felis chaus), two servals (Leptailurus serval), two tigers (Panthera tigris), three leopards (Panthera pardus), and 14 of 27 lions (Panthera leo). This is the first serologic analysis for T. gondii infection in exotic wild felids from Brazilian zoos.  相似文献   
2.
1. Several economically important traits in two Leghorn populations (over 9000 birds) were examined for additive and non‐additive components of genetic variance and sex‐linked effects. Data were analysed by two different statistical models based on least‐squares procedures.

2. Six different covariances were first calculated between relatives; i.e., full‐sibs, 3/4‐sisters, half‐sisters, dam‐daughters, grandam‐granddaughters and aunt‐nieces.

3. From the covariances, weighted least‐squares equations were used to obtain estimates of variance components for additive genetic, dominance, maternal and sex‐linkage effects.

4. The estimates of non‐additive components were highly variable but generally small compared with the additive genetic estimates.

5. In general this study suggests that for most traits, with the possible exception of rate of egg production, there is relatively little non‐additive genetic variation.

6. The consequences of possible negative correlations between additive effects and maternal effects are considered as they might apply to egg production in poultry.  相似文献   

3.
4.
BackgroundHistorically, positive bacterial cultures from the lower respiratory tract (LRT) have been considered clinically relevant when quantitative bacterial cultures of bronchoalveolar lavage fluid (BALF) were >1700 colony forming units (cfu)/mL. However, this threshold might not accurately predict a requirement for antibiotics.ObjectivesTo study whether quantitative BALF bacterial culture results were predictive of antibiotic requirement in dogs with LRT signs.AnimalsThirty‐three client‐owned dogs.MethodsCross‐sectional study. Dogs with positive quantitative bacterial culture of BALF were included. Dogs were divided into 2 groups, depending on whether they had a LRT infection requiring antibiotics (LRTI‐RA) or LRT disease not requiring antibiotics (LRTD‐NRA), based on thoracic imaging features, presence of intracellular bacteria on BALF cytology, and response to treatment. Predictive effect of cfu/mL and BALF total nucleated cell count (TNCC) on antibiotic requirement, adjusting for ongoing or prior antibiotic therapy and age, were studied using logistic regression.ResultsTwenty‐two and 11 dogs were included in the LRTI‐RA and LRTD‐NRA groups, respectively. The cfu/mL was not significantly predictive of antibiotic requirement, independent of ongoing or prior antibiotic treatment and age (LRTI‐RA: median, 10 000 cfu/mL; range, 10‐3 × 108; LRTD‐NRA: median, 10  000 cfu/mL; range, 250‐1.3 × 109; P = .27). The TNCC was not significantly predictive of antibiotic requirement when only dogs with bronchial disease were considered (LRTI‐RA: median, 470 cells/μL; range, 240‐2260; LRTD‐NRA: median, 455 cells/μL; range, 80‐4990; P = .57).Conclusion and Clinical ImportanceThe cfu/mL is an inappropriate measure for determining whether antibiotics are of benefit in dogs with LRT signs.  相似文献   
5.
Twenty-one free amino acids present in several samples of quince fruit (pulp and peel) and quince jam (homemade and industrially manufactured) were analyzed by GC/FID. The analyses showed some differences between quince pulps and peels. Generally, the highest content in total free amino acids and in glycine was found in peels. As a general rule, the three major free amino acids detected in pulps were aspartic acid, asparagine, and hydroxyproline. For quince peels, usually, the three most abundant amino acids were glycine, aspartic acid, and asparagine. Similarly, for quince jams the most important free amino acids were aspartic acid, asparagine, and glycine or hydroxyproline. This study suggests that the free amino acid analysis can be useful for the evaluation of quince jam authenticity. It seems that glycine percentage can be used for the detection of quince peel addition while high alanine content can be related to pear addition.  相似文献   
6.
The Austral papaya (Vasconcellea chilensis) is an endangered species that has valuable characteristics for introgression into other papaya species. These characteristics include disease resistance, cold tolerance and latex with low proteolytic activity. It is a species that grows under extreme environmental conditions of drought, salinity and temperature; it is found growing naturally in Chile but today only as three remnant populations. The results presented here, using inter simple sequence repeat molecular markers, along with morphological trait analyses, suggest that these relict populations are the result of a relatively recent fragmentation. This implies that the fragmentation has not yet had its full effect on the genetic variation and so emphasises the need for clear and urgent conservation measures to preserve the remaining genetic variation, particularly for the most northern of the three populations which is presently unprotected.  相似文献   
7.
Tropical Animal Health and Production - This study aimed to verify the reproductive seasonality in Saanen goats from distinct parity orders (nulliparous, primiparous, and pluriparous) throughout an...  相似文献   
8.
This paper analyzes the key principles on which the international traditional contracts and new engineering contract have been drafted as well as the contractual relations among the parties involved in the execution of the project. This paper concluded that the new engineering contract prepared by the Institute of Civil Engineers has shown its unique features in the principles and new management techniques and is able to stimulate good project management.  相似文献   
9.
Fall Armyworm Damaged Maize Plant Identification using Digital Images   总被引:6,自引:0,他引:6  
The objectives of precision agriculture are profit maximisation, agricultural input rationalisation and environmental damage reduction, by adjusting the agricultural practices to the site demands. The fall armyworm (Spodoptera frugiperda) is one of the most important maize pests in Brazil and the use of insecticide is the main control method. It is believed that site-specific control can be implemented by using a machine vision system. The objective of this work was to develop and evaluate an algorithm at simplified lighting conditions for identifying damaged maize plants by the fall armyworm using digital colour images. Images of damaged and non-damaged maize plants were taken in eight different stages and in three different light intensities. The proposed algorithm had two stages: the processing and the image analysis. During the first stage, the images were processed to create binary images where the leaves were segmented from the other pixels. At the second stage, the images were subdivided into blocks and classified as ‘damaged’ or ‘non-damaged’ depending on the number of objects found in each block. The algorithm correctly classified 94·72% of 720 images.  相似文献   
10.
In silvopastoral (SP) systems, forage responses depend on the microenvironment in which the plants develop. Our objective was to evaluate canopy and tillering characteristics of shaded 'Marandu' palisadegrass [Brachiaria brizantha (Hochst A Rich) Stapf, syn. Urochloa brizantha] under continuous stocking in a SP system. Treatments were one full sun (FS) and three shaded systems (silvopasture, SP) corresponding to distances from tree groves: 7.5 m north (SP1), and 15 m (SP2) and 7.5 m south (SP3) studied during two rainy seasons (Year 1 and Year 2). The tree in the SP system was Eucalyptus urograndis (hybrid of Eucalyptus grandis W. Hill ex Maiden × Eucalyptus urophylla S. T. Blake). The photosynthetic active radiation was greater in FS (923 μmol m-2 s-1), followed by SP2 (811 μmol m-2 s-1), SP1 (727 μmol m-2 s-1) and SP3 (673 μmol m-2 s-1). Forage accumulation in FS was 15% greater than the mean of SP1, SP2 and SP3 (10,663 kg DM/ha). There was no difference in net accumulation of leaf, stem and dead material, averaging 3,302, 3,420 and 4,063 kg DM/ha respectively. Leaf accumulation and accumulation rate were greater in Year 2, and leaf accumulation rate was similar among treatments (19 kg DM ha−1 day−1). Leaf proportion increased 14% from Year 1 to Year 2. Specific leaf area was greater for treatments SP1 and SP3 (193 cm2/g). Tiller population density was similar across treatments in Year 1. Shaded palisadegrass maintains leaf productivity similar to FS under continuous stocking in an SP system.  相似文献   
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