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1.
Fifty six 1,2,3-benzothiadiazoles and related compounds were evaluated as carbaryl synergists against the house fly (Musca domestica). Many of these were excellent synergists, the most active being those containing various combinations of halogen, alkyl, or alkoxy substituents in the 5- and/or 6-positions of the ring.Regression analysis on the data from 14 compounds for which substituents constants were available established that synergistic activity can be satisfactorily described by equations in terms of the hydrophobic bonding constant (π) and the homolytic free radical constant (σ ·).The results with compounds related to the 1,2,3-benzothiadiazoles suggest that synergistic activity is associated primarily with the diazosulfide moiety. 相似文献
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Amália Turner Giannico Elaine Mayumi Ueno Gil Daniela Aparecida Ayres Garcia Marlos Gonçalves Sousa Tilde Rodrigues Froes 《Veterinary research communications》2016,40(1):11-19
The aim of this study was to develop regression models for correlation of canine fetal heart development with body size to characterize normal development or suggest cardiac anomalies. Twenty clinically healthy pregnant bitches, either brachycephalic and non-brachycephalic, were examined ultrasonographically. Transabdominal fetal echocardiography was conducted every 4 days from the beginning of cardiac chambers differentiation until parturition. Ten cardiac parameters were measured: length, width and diameter of the heart; heart area; left and right ventricular dimensions; left and right atrial dimensions; and aortic and pulmonary artery diameter. Femoral length, biparietal diameter and abdominal cross-sectional area were also recorded. Regression equations were developed for each parameter of fetal body size, and linear and logarithmic models were compared. The model with the highest correlation coefficient was chosen to produce equations to calculate relative dimensions based on the correlations. Only the left-ventricular chamber differed between the two racial groups. Biparietal diameter was the independent parameter that produced the highest correlation coefficient for the most fetal cardiac dimensions, although good correlations were also observed using femoral length and abdominal cross-sectional area. Heart width and heart diameter were used as surrogates of cardiac development, as these measurements showed the best statistical correlation. Quantitative evaluation of fetal cardiac structures can be used to monitor normal and abnormal cardiac development. 相似文献
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Crude protein (CP) of forages can be separated into fractions of differentiated abilities to provide available amino acids in the lower gut of ruminants. This knowledge is critical to develop feeding systems and to predict animal responses. We have measured during two growing seasons (1996 to 1997 and 1997 to 1998) the CP fractions of common vetch fresh forage with the objective being to assess the influence of maturity on concentration of CP fractions (as a percentage of total CP) and fraction yields. Fraction B2, which represents true protein of intermediate ruminal degradation rate, was the largest single fraction in common vetch forage (about 40% of CP across seasons and maturity stages). Soluble fractions (A plus B1) were less than 50% of total CP while the unavailable fraction C ranged from 4 to 8% of total CP. As a result, the remaining fraction B3 (true protein of very low degradation rate) only represented 2 to 9% of total CP. Concentration and yield of fraction B3 increased (P < 0.05) from flowering to pod-filling. Results showed that undegraded dietary protein represented a small proportion of total CP in common vetch forage. Moving the harvesting stage from flowering to the pod filling phase allowed for greater yield of undegraded dietary protein. 相似文献
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L. Cardoso F. Gil M. A. Teixeira O. López-Albors R. Latorre A. Arencibia M. A. Rivero J. M. Vázquez 《Anatomia, histologia, embryologia》2005,34(S1):10-10
Computed tomography (CT) is a modern technique of image diagnosis particularly recommended in human medicine to evaluate the existence of pulmonary pathological changes such as neoplasms, metastasis, interstitial infiltrates, etc. In veterinary medicine, however, few anatomical and clinical CT studies in the dog have used apparatus of the latest generation, including injection of intravenous contrast and application of regional specific CT windows with different window width (WW) and window level (WL) to evaluate the lungs, the pulmonary vessels and the bronchial structures. This methodology allows the obtaining of clear CT images with high capacity of tissue discrimination and different shades of attenuation. In this work we have planned a tomographic study of the lungs of the dog by using a six-generation spiral CT scanner (Toshiba Ex Vision), belonging to the private Medical Institute of Radiology 'Irion' of Porto Alegre, Brazil. Four mixed-breed mature dogs (4–6 years, 15–20 kg) were used, two males and two females. The dogs were anaesthetized and kept in a maximum inspiration when obtaining the images. Dogs were placed in a stretcher in a ventral or sternal recumbency. Previously, the contrast urografin® was injected in the cephalic vein. Different CT windows were applied in order to increase the quality of the images: pulmonary window (WW 928; WL -680), high-resolution pulmonary window (WW 1085; WL -750), and soft tissue window (WW 652; WL -34). The use of intravenous contrast, different CT windows and a modern CT apparatus produced excellent images of the pulmonary parenchyma, the pleural cavity, the pulmonary veins, the lobular rami of the pulmonary artery and the lobular bronchi. 相似文献
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Gil MC Peña FJ Hermoso De Mendoza J Gomez L 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2003,50(10):484-487
This paper reports on the genital lesions observed in adult male and female goats from a commercial flock in the Extremadura region of southwestern Spain, following an outbreak of contagious agalactia syndrome caused by Mycoplasma agalactiae and M. putrefaciens. Although both species were isolated from several organs, M. putrefaciens was the only agent isolated from the genital lesions reported here, characterized by desquamative salpingitis and cystic catarrhal metritis in females and by testicular degeneration in males. Mycoplasma putrefaciens was isolated from the testes of only one of the males examined. 相似文献
7.
Ayala MD López Albors O García Alcázar A Abellán E Latorre R Vázquez JM Ramírez Zarzosa G Martínez F Gil F 《Anatomia, histologia, embryologia》2003,32(5):271-275
Muscle growth was studied in larvae of sea bass, Dicentrarchus labrax L., reared at two temperatures: real ambient temperature ( congruent with 15 degrees C during vitelline phase and increased gradually) and 19 degrees C from fertilization until the end of larval development. Muscle cellularity, body length and body weight were measured. Early temperature influenced larval development and so, pre-larval phase finished earlier at 19 degrees C than at ambient temperature (4 and 6 days, respectively). Temperature also affected muscle growth such that at hatching and at mouth opening hypertrophy of muscle fibres was greater at 19 degrees C (P < 0.05), whereas hyperplasia was similar in both groups. After 25 days, the cross-sectional area of the white muscle was greater at 19 degrees C (P < 0.05), which was mainly associated with a higher proliferation of new white muscle fibres. At this stage the body length was also higher at 19 degrees C. Metamorphosis finished earlier in fish reared at 19 degrees C (52 days) than at natural temperature (82 days). At this developmental stage body length and cross-sectional area of the myotome were similar in both groups. However, muscle cellularity differed between groups. Thus, hypertrophy of muscle fibres was higher in fish reared at ambient temperature (P < 0.05), whereas proliferation of new muscle fibres was higher at 19 degrees C (P > 0.05). 相似文献
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Ayala MD López-Albors O Gil F Latorre R Vázquez JM García-Alcázar A Abellán E Ramírez G Moreno F 《Anatomia, histologia, embryologia》2000,29(4):235-241
In order to determine the temperature effect on the axial muscle growth of sea bass, a stock of larvae was subjected to the following incubation and cultivation temperatures, respectively: 15 degrees C/ambient, 15/17 degrees C, 17 degrees C/ambient and 17/17 degrees C. In all groups the cross-sectional area of white and red muscles and the number and average area of the white and red muscle fibres were quantified. Results showed that the embryonic period, pre-larval phase and the end of metamorphosis were accelerated at higher temperatures. During the endogenous feeding period, muscle growth took place by fibrillar hypertrophy, and was not influenced by the temperature. Thereafter (external feeding) muscular hyperplasia began, and growth of all the muscular parameters was favoured by the effect of high incubation and cultivation temperatures, with the latter having higher influence. High incubation temperature had an slight effect on muscle growth and body length, which was only observed from 15 days. Metamorphosis finished at 3 +/- 0.4 cm in all the larvae, but this length was earlier reached at higher temperatures. At 120 days, the largest growth was obtained in the larvae maintained at a higher temperature. 相似文献
10.
Flores EF Gil LH Botton SA Weiblen R Ridpath JF Kreutz LC Pilati C Driemeyer D Moojen V Wendelstein AC 《Veterinary microbiology》2000,77(1-2):175-183
Nucleotide sequencing and phylogenetic analysis of Brazilian bovine viral diarrhea virus (BVDV) field isolates identified four viruses belonging to the genotype 2. Comparison of 5' UTR sequences from these isolates to those of North American BVDV type 2 revealed genomic variations that correlated with the geographic origins of the isolates. Two of the Brazilian type 2 viruses were isolated from clinical cases of gastroenteric/respiratory disease and two were isolated from healthy bovine fetuses. The clinical cases affected young animals (8- and 18-months-old) and were characterized by diarrhea, respiratory signs, extensive oral and digestive tract erosions, conjunctival and vulvar congestion, occasional digestive bleeding and vulvar and heart petechial hemorrhage. Antigenic analysis of these isolates with a panel of 10 monoclonal antibodies revealed marked antigenic differences in the major envelope glycoprotein, gp53/E2, compared to standard laboratory and vaccine BVDV strains. In addition, virus-specific antisera raised to Brazilian BVDV type 2 viruses displayed very low serological cross-reactivity with standard BVDV type 1 strains. Differences up to 64-fold in cross-neutralization titers were observed between BVDV type 1 and Brazilian BVDV type 2 isolates. The identification of BVDV type 2 among Brazilian cattle may have important implications for epidemiological studies, diagnostic and immunization strategies. Furthermore, the low neutralizing activity of BVDV type 1 antisera against the recently identified Brazilian BVDV type 2 isolates raises the question about the degree of protection conferred by BVDV vaccines, most of them based on a single type 1 strain. 相似文献