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31.
Maiara G. Blagitz Fernando N. Souza Camila F. Batista Soraia A. Diniz João Paulo A. Haddad Nilson R. Benites Priscilla A. Melville Alice M. M. P. Della Libera 《Tropical animal health and production》2014,46(1):127-132
The aim of this study was to investigate the relationship between clinical findings and bacterial isolation in milk samples of meat-producing ewes. The study was conducted in 17 commercial flocks and 550 udder halves from suckling Santa Ines ewes. Initially, the clinical examination of the mammary glands and teats was performed by visual inspection and palpation of the teats and udder halves; then a scoring system was devised for all the findings. After that, the strip cup test and the California mastitis test (CMT) were performed. Then, milk samples for somatic cell counts (SCCs) and bacteriological analyses were collected. Staphylococci bacteria were the main etiological agent isolated in the present study. Upon investigation of the correlations between bacterial isolation and the clinical findings, only the presence of teat injury, pendulous udder, and alterations in the palpation of the teat were associated with bacterial isolation. A significant correlation between bacteriologically positive milk samples and CMT and SCC was also found. Thus, some clinical findings appeared as a risk factor for bacteriologically positive milk samples and can be used as a tool in mastitis control programs. However, a complete and extensive diagnosis, an appropriate therapy, and an efficient mastitis control program will require the combination of clinical examination, microbiological tests, and SCC. 相似文献
32.
Daiane Güllich Donin Raquel de Arruda Leme Alice Fernandes Alfieri Geraldo Camilo Alberton Amauri Alcindo Alfieri 《Tropical animal health and production》2014,46(3):523-528
Porcine teschovirus (PTV), Porcine sapelovirus (PSV) and Enterovirus G (EV-G) have been associated with enteric, respiratory, reproductive and neurological disorders. Although Brazil is the world’s fourth largest producer and exporter of pork, no information on the occurrence of PTV, PSV and EV-G infections is available for Brazilian pig herds. This study aimed to investigate the occurrence of Porcine enteric picornavirus infections in pig farms located in three distinct geographical regions of Brazil. Forty randomly selected diarrhoeic and normal consistency faeces of suckling (n?=?22) and nursery (n?=?18) pigs from farms located in 21 distinct cities of the Southern, Southeast, and Midwest regions of Brazil were evaluated by nested-RT-PCR assays. Suckling piglets presented the expected amplicon size for PTV (158 bp) and EV-G (313 bp) in single and mixed infections in 40.9 % (9/22) of the faecal samples. PSV amplicon (212 bp) was not detected in this age group. For nursery pigs, Porcine enteric picornaviruses amplicons were present in 77.8 % (14/18) of the faecal samples. PTV and EV-G were detected in single and mixed infections, while PSV was detected only in two samples in co-infection with PTV and EV-G in this age group. The Brazilian regions evaluated presented at least two of the tested viruses. Sequencing analysis revealed high similarities to the related viruses (95.3 to 99.2 % for PTV, 94.2 to 98.5 % for PSV and 86 to 100 % for EV-G). For the first time PTV, PSV and EV-G have been molecularly detected and characterised in pig faecal samples in Brazil. 相似文献
33.
The aim of this retrospective study was to follow the progression of radiographic changes in intentionally retained roots of teeth affected with tooth resorption type 2 in cats. Emphasis was placed on assessment of degree of resorption as well as the occurrence of inflammatory changes in tooth roots. The results confirm that crown amputation is an adequate treatment in cats for teeth affected by type 2 resorption. 相似文献
34.
35.
ABSTRACT We describe a method to evaluate the virulence of Mycosphaerella fijiensis, the causal agent of black leaf streak disease (BLSD) of banana and plantain. The method is based on the delivery of weighed slurries of fragmented mycelia by camel's hair brush to 5-by-5-cm areas on the abaxial surface of banana leaf blades. Reliable BLSD development was attained in an environmental growth chamber with stringent lighting and humidity controls. By localizing inoculum onto small areas of large leaves, we achieved a dramatic increase in the number of strains that can be tested on each leaf and plant, which is critical for comparing the virulence of numerous strains concurrently. Image analysis software was used to measure the percentage of each inoculated leaf section showing BLSD symptoms over time. We demonstrated that the level of disease of four isolates was correlated with the weight of the mycelium applied and relatively insensitive to the degree of fragmentation of hyphae. This is the first report demonstrating that weighed mycelial inoculum, combined with image analysis software to measure disease severity, can be used to quantitatively assess the virulence of M. fijiensis under rigorously controlled environmental conditions. 相似文献
36.
Tenni Daniele Sinetti Alice Waldner Maya Torriani Stefano F. F. Romani Marco 《植物病害和植物保护杂志》2021,128(6):1705-1709
Journal of Plant Diseases and Protection - Rice blast disease, caused by Pyricularia oryzae Cavara, is considered the most destructive rice disease in Italy. Quinone outside inhibitor (QoI)... 相似文献
37.
38.
Maria Suely Pagliarini Claudicéia Risso-Pascotto Alice Maria de Souza-Kaneshima Cacilda Borges do Valle 《Euphytica》2008,164(1):181-187
Sexuality is correlated with diploidy and apomixis with polyploidy in the Brachiaria genus. Brachiaria ruziziensis is a key species in Brachiaria breeding due to its obligate sexuality and intrinsic agronomic qualities. Interspecific crosses in the genus became feasible
only when a few diploid accessions of B. ruziziensis were artificially tetraploidized and remained sexual. Hybridization has been done since, using natural tetraploid apomictic
accessions of B. brizantha or B. decumbens as pollen donors. Twenty two accessions of B.
ruziziensis from the Embrapa Beef Cattle germplasm collection (Campo Grande, MS, Brazil) were cytologically analyzed: 16 are natural
diploids (2n = 2x = 18) and six are artificially induced tetraploids (2n = 4x = 36). The meiotic behavior in the 16 diploid accessions varied. The mean of meiotic abnormalities per accession ranged from
zero to 24.46%. Meiotic behavior in the induced tetraploid accessions also varied with the mean of meiotic abnormalities ranging
from 5.20% to 54.71%. The most common abnormalities observed in both the diploid and the tetraploid accessions, were those
related to irregular chromosome segregation. In one tetraploid accession, with a high frequency of those, other irregularities
involving chromosome orientation at metaphase plate and chromosome convergence to the poles, a meiotic mutation known as divergent spindle, were recorded. Meiotic behavior should be considered in selecting potential genitors for breeding. 相似文献
39.
Ard G. Lengkeek Alice Muchugi Mwangi Caroline A. C. Agufa Joseph O. Ahenda Ian K. Dawson 《Agroforestry Systems》2006,67(3):293-300
It is possible that current tree domestication practices undertaken by farmers reduce the genetic base of tree resources on
farms, raising concerns regarding the productivity, sustainability and conservation value of agroforestry ecosystems. Here,
we assessed possible changes in genetic variation during domestication in the important and heavily utilised timber species,
Vitex fischeri Gürke (syn. Vitex keniensis), by comparing geographically proximate forest and farm material in central Kenya. Employing RAPD analysis, a total of 104
polymorphic markers revealed by five arbitrary primers were scored in a total of 65 individuals, 32 from forest and 33 from
farmland. Despite concerns of possible genetic erosion, forest and farm stands did not differ significantly in levels of genetic
variation, with H values of 0.278 and 0.269, respectively. However, Mantel tests did reveal greater geographically related associative genetic
structure among individuals in farm rather than forest material, with r
M values of 0.217 and 0.114, respectively. A more detailed analysis of structure suggested this could be due to local variation
in origin of some on-farm trees. Implications of data for the genetic management of V. fischeri stands during farmer-led tree domestication activities are discussed. At present, there appears little reason to reject on-farm
V. fischeri as a source of germplasm for future on-farm planting or for conservation purposes, although this situation may change and
will require monitoring. 相似文献
40.
Isabelle Boulogne Reginaldo Constantino Nadine Amusant Michaël Falkowski Alice M. S. Rodrigues Emeline Houël 《Journal of pest science》2017,90(1):19-37
The genus Nasutitermes is among the most abundant wood-feeding Termitidae and an extremely diverse and heterogeneous group in terms of its biogeography and morphology. Despite the major role of several Nasutitermes species as structural pests, the phylogenetic status of this genus is still unclear, along with a confused taxonomy and species identification remaining difficult. The first aim of this review was thus to gather and discuss studies concerning the taxonomic status of the genus Nasutitermes in order to clarify this crucial point. Then, our goal was to gain new insights into the management of N. corniger, considered to be the most economically detrimental pest of this genus in South America and a Nasutitermes model species, while filtering available information concerning its biology through the prism of termite control, as well as critically examine the existing methods. We indeed strongly believe that increasing our knowledge of this species’ biological strategies is the key to progress in the challenging question of their sustainable management. 相似文献