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11.
Journal of Plant Diseases and Protection - Mulberry (Morus spp.), represents a set of plants grown in Brazil for production of fruits, leaves for feeding silkworms and ruminant animals, and for...  相似文献   
12.
Thirty, 4-month-old entire Santa Ines lambs were grazed on an Andropogon gayanus pasture, during a 34-week period (rainy season weeks 0-20 and dry season weeks 21-34) and allocated in two treatment groups (n = 15) each with different protein supplementation: high protein (HP-19% CP) and low protein (LP-11% CP). These were subdivided into those receiving anthelmintic treatment (c) (n = 7) and without anthelmintic treatment (i) (n = 8). The objective was to evaluate the effects of supplementation with protein on resistance and resilience to natural helminth infection of hair breed lambs. Lamb weight, blood collection and faecal egg counts (FEC) were carried out monthly. The lambs were slaughtered after 34 weeks, when worm burdens, worm length and eosinophil cell counts were taken. The sheep on treatments HPc and HPi were heavier in live weight than those from LPi and LPc (P < 0.05) at the end of the rainy period. The HPc group finished heavier (P < 0.05) than the other groups in the dry season, which had no significant differences between them. The predominant species of nematode found was T. colubriformis followed by H. contortus, Trichuris globulosa and Moniezia expansa. Animals on HPi had lower FEC than LPi (P < 0.05). The number of worms was lower for both HP groups (P < 0.05) with worm length shorter in the HPc group (P < 0.05) compared with all other groups. The number of eosinophils was higher in animals in the LPi group, which also showed anaemia and lower plasma urea at the end of the dry season. Diet supplementation with high protein was able to improve resilience and resistance to natural infection by endoparasites during the rainy season. In the dry season there was a decrease in both of these traits, which were intimately linked to the quality of available forage under tropical conditions.  相似文献   
13.
Recent outbreaks of Verticillium wilt diseases in various vegetable crops have been reported in Brazil. This fact was our initial stimulus to carry out a nationwide survey aiming to determine their causal agent(s). Thus far, Verticillium dahliae has been reported as the predominant species based solely on morphological traits. As other Verticillium species can be associated with wilt diseases, we characterized a collection of 80 isolates, collected across 10 agricultural Brazilian regions, by combining morphological, biological, and molecular traits. A multilocus approach was employed for identification of Verticillium species with information from three genomic regions (ribosomal internal transcribed spacer region, glyceraldehyde-3-phosphate dehydrogenase, and actin genes). Only 21 out of the 80 isolates were unable to produce microsclerotia in culture. The analyses of all genomic regions indicated V. dahliae as the sole species associated with vascular wilt of distinct hosts, including major solanaceous vegetables and other hosts such as strawberry, okra, and cacao. Pathogenicity tests confirmed the infection by the V. dahliae isolates and the development of typical disease symptoms on their original hosts. This is the first nationwide characterization of Verticillium isolates associated with major vegetable crops in Neotropical areas. This provides valuable information to design sound management strategies for these diseases, mainly for establishing efficient rotation systems and for the development of resistant cultivars.  相似文献   
14.
Thielaviopsis and related taxa are responsible for losses in several agricultural crops. In carrot these pathogens can cause black rot, mainly after harvesting. Molecular studies using species-specific DNA sequences are the principal tools for accurate identification of these pathogens. The objective of this work was to investigate which taxa are associated with black rot in carrot in Brazil using gene markers and Bayesian phylogenetic analysis. Eighteen isolates were obtained from carrots with symptoms of black rot. Through morphological characteristics all isolates were classified as Thielaviopsis-like. Bayesian inference using only MCM7 sequences and a concatenated data set (LSU, MCM7 and 60S rRNA) allowed identification of all isolates as belonging to Berkeleyomyces basicola. All isolates induced black rot in carrot. Although our studies include a small number of isolates, the results indicate the likely predominance of B. basicola in causing black rot in carrot in Brazil, and that MCM7 sequences are enough to distinguish the Berkeleyomyces species by Bayesian inference.  相似文献   
15.
European Journal of Plant Pathology - Corynespora cassiicola isolates display morphological, pathogenic, and ecological diversity, inducing target spot-like diseases in more than 500 hosts...  相似文献   
16.
In nature, plants have to cope with different types of stress. Stress by pathogens can be avoided through a plant response called Systemic Acquired Resistance (SAR). SAR is regulated by salicylic acid amongst other signals. Recently, several findings help us to have a deeper knowledge of SAR. On one hand, two different research groups have reported three different putative salicylic acid receptors; on the other hand, another two groups of scientists have found evidence about the basis of transgenerational priming in inducing resistance against pathogens. All these discoveries are discussed in the frame of the recent literature.  相似文献   
17.
Elephant grass, sugarcane, and rice bran in diets for confined sheep   总被引:1,自引:0,他引:1  
We aimed to evaluate the effects of diets, based on elephant grass or sugarcane as roughage and corn meal or rice bran as energy concentrate, on performance and body composition in terms of diet intake and digestibility. A total of 30 Santa Ines crossbreds (SIC), castrated male sheep with 19.8?±?2.0?kg initial body weight (BW) were used. Six animals were slaughtered at the onset of the experiment to estimate the initial body composition for the other animals. The remaining 24 animals were distributed in a completely randomized 2?×?2 factorial design, with four treatments (two roughages and two concentrates) and six replicates. The sheep were slaughtered when they reached 30.0?kg BW. Elephant grass diets provided higher intake and digestibility than sugarcane diets for the following contents: dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fibre, minerals, total carbohydrates (TC), and total digestible nutrients (TDN). Among the concentrates, corn meal diets were associated with higher intakes than rice bran diets for the following contents: DM, OM, CP, TC, and TDN. Animals from all of the treatments exhibited low average daily weight gain and low protein and high fat and energy body levels. Sugarcane and rice bran can be used as ingredients in diets for sheep with low weight gain potential. Regardless of roughage or concentrate types used in diets for confined SIC sheep, performance and body composition remained unaltered.  相似文献   
18.
A 2-year-old female mixed-breed cat weighing 2.7 kg presented with recurrent rectal prolapse. The following report describes its treatment by laparoscopic-assisted incisional colopexy using two portals. The procedure was effective and without trans- or postoperative complications. Recurrent prolapses did not recur in the 2 months of postoperative observation.  相似文献   
19.
We report the initial characterization of a leptospiral isolate, Leptospira interrogans, serogroup Sejroe, serovar Hardjo, genotype Hardjoprajitno, strain Norma, and its relatedness with L. interrogans, serogroup Sejroe, serovar Hardjo, genotype Hardjoprajitno, strain Hardjo and Leptospira borgpetersenii, serogroup Sejroe, serovar Hardjo, genotype Hardjobovis, strain Sponselee. The Norma strain singled out during a leptospirosis outbreak in cattle immunized with antigens from the reference strain Hardjoprajitno (OMS). By applying a microscopic agglutination serological test (MAT) to cattle (n = 2966) with symptoms of leptospirosis between 2003 and 2007, more than 50% of sera were found positive for one of the following serotypes: Hardjoprajitno (31–21%), Hardjo Norma (46–40%), Hardjo hardjobovis (18–10%), Mini (8–4%) and Wolffi (7–4%). In immunization trials using six isolates plus Norma isolate, the remission of MAT in these isolates was observed following 6 months of the initial vaccination. To provide molecular ground for the high MAT Norma frequency found in these isolates, a DNA polymorphic analysis was conducted by comparing the Norma isolate with reference strains Hardjoprajitno and Sponselee. The polymorphic analysis in secY showed five base changes in Norma relative to Hardjoprajitno strain, corresponding to 98% identity, while Sponselee displayed 49 polymorphic sites relative to the Hardjoprajitno strain, representing 80% identity. The alignment of secY translated sequences shows no differences between Hardjoprajitno and Norma, and eight polymorphisms between genotype hardjoprajttno and strain Sponselee. Three‐dimensional modelling located these variations within the loop region connecting helices 7 and 8 from secY which is less conserved. DNA sequencing of 23S ribosomal conserved fragment revealed a single polymorphism between Hardjoprajitno and Norma, and 13 polymorphisms between strains Sponselee, Hardjoprajitno and Norma. The differences between Hardjo and Norma were confirmed by low stringency single‐specific primer polymerase chain reaction (LSSP‐PCR) signature experiments with the primer G2, using as template the 285 bp fragment initially amplified with G1/G2 primers.  相似文献   
20.
We aimed to evaluate the effects of maternal nutrition (MN) and foetal sex on the intestinal development of bovine foetuses throughout different days of gestation (DG). Forty‐four multiparous, dry Holstein × Gyr cows with average initial body weight of 480 ± 10 kg were fed the same diet of either restricted feeding at 1.15% of body weight (CO, n = 24) or fed ad libitum (overnourished, ON, n = 20). Six cows from CO group and five cows from ON group were slaughtered at 139, 199, 241 and 268 DG, and foetuses were necropsied to evaluate the intestinal development. The mass, length and density of foetal intestines were not affected by MN (p ≥ 0.260). An interaction between MN and DG was observed for the villi length of jejunum (p = 0.006) and ileum (p < 0.001). Villi length of jejunum and ileum was higher (p < 0.10) in foetuses from ON‐fed cows than in foetuses from CO‐fed cows at 139 DG. However, at 199 DG, the villi length of jejunum and ileum of foetuses from CO‐fed cows was higher than in foetuses from ON‐fed cows. Despite these differences, MN did not affect the villi length of jejunum and ileum at 268 DG (p > 0.10). Female foetuses had greater small intestine mass (p = 0.093), large intestine mass (p = 0.022), small intestine mass in proportion to body mass (p = 0.017) and large intestine mass in proportion to body mass (p < 0.001) than male foetuses. Female foetuses had also longer small intestine (p = 0.077) and greater small intestine density (p = 0.021) and villi length of jejunum (p = 0.001) and ileum (p = 0.010) than males. We conclude that MN affects the pathway for the development of foetal villi length throughout the gestation in bovine foetuses without changing the final villi length. Female foetuses had higher intestinal mass, density and villi length than males during the foetal phase in bovines.  相似文献   
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