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51.
Javier Bezos Sergio Marqués Julio Álvarez Carmen Casal Beatriz Romero Ana Grau Olga Mínguez Lucas Domínguez Lucía de Juan 《Research in veterinary science》2014
Goats can act as reservoirs for tuberculosis (TB) infection. The main etiological agents of TB in goats are Mycobacterium caprae and Mycobacterium bovis and they infect also a wide range of domestic and wild animals and humans. Control programmes based mainly on the application of single and comparative intradermal tuberculin (SIT and SCIT respectively) tests are being implemented in certain regions of Spain with a high density of caprine flocks as Castilla y León, including goats with epidemiological relationship with cattle. The aim of this study was to evaluate the performance of the intradermal tests in naturally TB-infected caprine flocks from this region. The study was performed using data from 17,450 goats in 54 different flocks that were classified as TB-infected in the control programmes executed in 2010 and 2011. Data from 1237 goats from 7 dairy flocks depopulated after the first intradermal testing were used to estimate the sensitivity (Se) using bacteriology as the gold-standard. Overall Se of the SIT test using the severe interpretation was 43.9% (CI 95%, 40.4–47.4) and decreased to 38.8% (CI 95%, 35.5–42.3) using the standard interpretation. Overall Se of the SCIT test ranged between 21.3% (CI 95%, 17.6–25.4) and 7% (CI 95%, 4.9–9.8) depending of the interpretation criteria. A significant weak positive correlation was found between age and skin fold thickness (Spearman’s test p < 0.05). Results from this study yielded, in general, low Se values probably due the systematic detection and slaughter of reactors as a consequence of the eradication programme in previous years or the presence of factors that may interfere in the diagnosis. Therefore, these results suggest the necessity of including ancillary diagnostic tools and/or strict interpretation criteria to maximize detection of positive animals in infected settings. 相似文献
52.
Carmen Lucia de Souza Rech José Luiz Rech Vivian Fischer Mabel Mascarenhas Wiegand Heden Luiz Marques Moreira Maria Teresa Moreira Osório Frank Siewerdt 《Tropical animal health and production》2014,46(1):191-195
The objective of this trial was to evaluate the effect of whole rice meal (WRM) inclusion in the concentrate upon body development, carcass traits, and meat quality of lambs. Twenty-four castrated lambs with an average initial body weight of 17.90?±?2.72 kg were randomly blocked according to two genetic groups (Corriedale and Texel by Corriedale crossbreds). Three isocaloric (11.3 MJ/kg of metabolizable energy) and isonitrogenous (17 % crude protein) diets were offered to the animals for 74 days. Diets consisted of 40 % forage and 60 % concentrate diet, on a dry matter basis, with 0, 15, or 30 % of WRM inclusion into the concentrate. Body growth (after slaughter), carcass, and meat traits were evaluated on each animal. Results obtained indicated that genotype did not affect body growth, carcass, and meat traits except for yellowness. No significant interaction between diet and genotype were detected. Inclusion of up to 30 % WRM did not significantly (P?>?0.05) affect body growth, carcass, and meat traits, except for meat color. Meat luminosity progressively increased (36.32?+?0.055X) while redness (15.13???0.03X) decreased with the inclusion of WRM in the diet, but still remained within acceptable values. The study indicates that WRM may be included up to 30 % in the concentrate replacing corn without adverse effects upon body development, carcass traits, and meat quality of lambs. 相似文献
53.
Pilar Sancho Carmen Tejedor Rebeca S Sidhu-Mu?oz Luis Fernández-Lago Nieves Vizcaíno 《Veterinary research》2014,45(1):61
Brucella ovis causes ram contagious epididymitis, a disease for which a specific vaccine is lacking. Attenuated Brucella melitensis Rev 1, used as vaccine against ovine and caprine brucellosis caused by B. melitensis, is also considered the best vaccine available for the prophylaxis of B. ovis infection, but its use for this purpose has serious drawbacks. In this work, two previously characterized B. ovis attenuated mutants (Δomp25d and Δomp22) were evaluated in mice, in comparison with B. melitensis Rev 1, as vaccines against B. ovis. Similarities, but also significant differences, were found regarding the immune response induced by the three vaccines. Mice vaccinated with the B. ovis mutants developed anti-B. ovis antibodies in serum of the IgG1, IgG2a and IgG2b subclasses and their levels were higher than those observed in Rev 1-vaccinated mice. After an antigen stimulus with B. ovis cells, splenocytes obtained from all vaccinated mice secreted similar levels of TNF-α and IL12(p40) and remarkably high amounts of IFN-γ, a crucial cytokine in protective immunity against other Brucella species. By contrast, IL-1α -an enhancer of T cell responses to antigen- was present at higher levels in mice vaccinated with the B. ovis mutants, while IL-10, an anti-inflammatory cytokine, was significantly more abundant in Rev 1-vaccinated mice. Additionally, the B. ovis mutants showed appropriate persistence, limited splenomegaly and protective efficacy against B. ovis similar to that observed with B. melitensis Rev 1. These characteristics encourage their evaluation in the natural host as homologous vaccines for the specific prophylaxis of B. ovis infection. 相似文献
54.
Marta González-Warleta José Antonio Castro-Hermida Javier Regidor-Cerrillo Julio Benavides Gema álvarez-García Miguel Fuertes Luis Miguel Ortega-Mora Mercedes Mezo 《Veterinary research》2014,45(1)
Neospora caninum has been detected only sporadically in cases of ovine abortion, and it has therefore traditionally been considered as an unimportant parasite in small ruminants. This study was carried out with the aim of identifying the pathogen causing serious reproductive problems on a commercial sheep farm. Sera from all rams and ewes tested negative for antibodies against Border disease virus, Schmallenberg virus and Coxiella burnetii, and infections by these agents were therefore ruled out. Nevertheless, seropositivity to N. caninum and/or Toxoplasma gondii was detected, although the seroprevalence was higher in the case of N. caninum. The percentage of lambings and the number of lambs per dam were significantly lower in ewes that were seropositive to N. caninum while no effect on these parameters was detected in ewes that were seropositive to T. gondii. There was also no evidence of infection by T. gondii in the foetal/lamb tissues analyzed by PCR and/or immunohistopathological techniques. On the contrary, the DNA of N. caninum was detected in 13 out of 14 foetuses/lambs descendant from dams seropositive to this parasite. Characteristic lesions caused by N. caninum and/or its antigen were also detected. Genotyping of the N. caninum DNA revealed only two closely related microsatellite multilocus genotypes. The results clearly demonstrate that infection by N. caninum was the cause of the low reproductive performance of this sheep flock. 相似文献
55.
Carmen RODENAS Inmaculada PARRILLA Jordi ROCA Emilio Arsenio MARTINEZ Xiomara LUCAS 《The Journal of reproduction and development》2014,60(5):355-361
The aim of this study was to evaluate the effects of rapid cooling prior to freezing on frozen-thawed canine sperm quality.
In experiment 1, centrifuged ejaculates from 6 dogs were pooled, split into 4 aliquots and cryopreserved by the Uppsala
procedure using different cooling rates (control, cooling speed 18 C/90 min and average cooling rate 0.2 C/min; rapid,
cooling speed 18 C/8 min and average cooling rate 2.25 C/min) in combination with 2 glycerol addition protocols (fractionated
or unfractionated). In experiment 2, centrifuged ejaculates from 4 dogs were processed individually using the same cooling
rates described in experiment 1 in combination with an unfractionated glycerol addition protocol. Each of the experiments was
replicated 5 times. Sperm quality was evaluated after 30 and 150 min of post-thawing incubation at 38 C. Total motility (TM),
progressive motility (PM) and quality of movement parameters were assessed using a computerized system, and sperm viability
(spermatozoa with intact plasma and acrosome membranes) was assessed using flow cytometry (H-42/PI/FITC-PNA). Values for TM,
PM, viable spermatozoa and the quality of movement parameters after thawing were not significantly affected by the cooling
rate. The interaction between the cooling rate and the added glycerol protocol was not significant. There were significant
differences among the males (P<0.01) in the sperm quality parameters evaluated after thawing. The interaction between the
males and the cooling rate was not significant. In conclusion, canine spermatozoa can be cryopreserved using the Uppsala
method at an average cooling rate of 2.25 C/min prior to freezing together with addition of fractionated or unfractionated
glycerol. 相似文献
56.
Guillermo Riesco Muñoz Óscar Santaclara Estévez Juan Gabriel Álvarez González Esther Merlo Sánchez 《European Journal of Forest Research》2014,133(4):623-630
The aim of this study was to establish the sources of variation in maritime pine wood properties related to appearance and strength, because of the importance of this wood in the sawing industry in Galicia (NW Spain). Ten trees from each of ten plots of the species (i.e., 100 trees) growing in Galicia were felled and sawn to produce the structural planks required for studying the presence of external strength-reducing characteristics. The planks were sampled from the basal logs to 16 m height in the stems, yielding cross sections of target dimensions 100 × 40 mm to 200 × 200 mm. We propose a model in which individual tree height and dominant height are used to predict the knottiness of planks from trees in mature stands. The abundance of externally visible knots on faces and edges of sawn planks is therefore more dependent on the stand location than on the prior silvicultural treatment of the stand. 相似文献
57.
Inter-specific competition and management modify the morphology, nutrient content and resorption in Scots pine needles 总被引:1,自引:1,他引:0
Irantzu Primicia J. Bosco Imbert M. Carmen Traver Federico J. Castillo 《European Journal of Forest Research》2014,133(1):141-151
Influence of tree-to-tree competition on nutrient resorption is still not well understood. To contribute filling this gap, we assessed the effects of thinning (0, 20 and 30 % extraction of basal area) and canopy type (beech–pine vs. pine subplots) on needle dry weight, needle length, nutrient content and nutrient resorption (N, P and K) in Scots pine (Pinus sylvestris) needles of different cohorts, 8–9 years after thinning. Thinning and canopy type often concurrently affected needle morphology (e.g. lighter and shorter needles in 30 % thinning, heavier and longer needles in pine canopy on the first year of study) and nutrient content (e.g. decrease in N, P and K in 30 %; N, P and K higher in pine canopy on the first year of study). However, effects of thinning appeared only in older cohorts for N and P but were found in old and new cohorts for needle dry weight, needle length and K, indicating that some thinning effects remained after 8–9 years. Canopy effects on morphology and nutrient content were more frequent in recent cohorts, in relation to an increase in beech cover over time. While no clear effects of thinning on the nutrient resorption were observed, higher values were observed in the pine than in the mixed canopy, which could be related to a higher Scots pine stem growth in those patches. The observed differences between treatments will likely increase as the stand develops, probably leading to beech trees being dominant, and as future thinnings are carried out. 相似文献
58.
M. E. Garci J. E. Trigo S. Pascual A. F. González F. Rocha A. Guerra 《Aquaculture International》2007,15(1):19-24
The presence of the non-indigenous species, the black-pygmy mussel Xenostrobus securis, is reported here for the first time in an intense shellfish farming area off Galicia (NW Spain). Very high concentrations
of this mytilid bivalve have colonized estuarine waters located at the inner part of the Ria de Vigo. The invasive role of
X. securis is discussed in the context of the wide ecological tolerance of the species and the recent finding of settlements of this
species on numerous colonies of the economically-important blue mussel Mytilus galloprovincialis. The mode of introduction of the black-pygmy mussel is also discussed in relation to human management activities. 相似文献
59.
Douglas J. Bruggeman Thorsten Wiegand Jeffrey R. Walters Fernando González Taboada 《Landscape Ecology》2014,29(4):639-653
Dispersal is a critical biological process that contributes to the persistence of species in complex and dynamic landscapes. However, little is known about the ability of different types of data to reveal how species interact with landscape patterns during dispersal. Further, application of process-based, landscape-scale models able to capture the influence of land use and climate change are limited by this lack of dispersal knowledge. Here we highlight a method for building such models when dispersal parameters are unknown, but information on the mating system and survival are available. We applied a common statistical framework, rooted in information theory, to contrast the ability of abundance, movement, and genetic data to estimate dispersal parameters for endangered Red-cockaded woodpecker (RCW), using an individual-based, spatially-explicit population model. Dispersal was modeled as a multifaceted process in which foray distance, long-distance dispersal, competition for mates, and landscape permeability were treated as uncertain. We found that movement data are three-times more powerful than abundance data collected at the same spatial and temporal scales. However, habitat occupancy data collected over much a shorter time scale but at regional spatial scales were very effective for estimating dispersal. We also found that one-year of abundance data provided a similar reduction in uncertainty as genetic differences among breeding groups estimated using a 24-year pedigree. Substituting population genetic data for movement and abundance data often led to the same parameter values, but not always. Our study highlights important differences in the information content of data commonly collected in the field. 相似文献
60.
Rodrigo Gutierrez‐Quintana Julien Guevar Catherine Stalin Kiterie Faller Carmen Yeamans Jacques Penderis 《Veterinary radiology & ultrasound》2014,55(6):585-591
Congenital vertebral malformations are common in brachycephalic “screw‐tailed” dog breeds such as French bulldogs, English bulldogs, Boston terriers, and pugs. The aim of this retrospective study was to determine whether a radiographic classification scheme developed for use in humans would be feasible for use in these dog breeds. Inclusion criteria were hospital admission between September 2009 and April 2013, neurologic examination findings available, diagnostic quality lateral and ventro‐dorsal digital radiographs of the thoracic vertebral column, and at least one congenital vertebral malformation. Radiographs were retrieved and interpreted by two observers who were unaware of neurologic status. Vertebral malformations were classified based on a classification scheme modified from a previous human study and a consensus of both observers. Twenty‐eight dogs met inclusion criteria (12 with neurologic deficits, 16 with no neurologic deficits). Congenital vertebral malformations affected 85/362 (23.5%) of thoracic vertebrae. Vertebral body formation defects were the most common (butterfly vertebrae 6.6%, ventral wedge‐shaped vertebrae 5.5%, dorsal hemivertebrae 0.8%, and dorso‐lateral hemivertebrae 0.5%). No lateral hemivertebrae or lateral wedge‐shaped vertebrae were identified. The T7 vertebra was the most commonly affected (11/28 dogs), followed by T8 (8/28 dogs) and T12 (8/28 dogs). The number and type of vertebral malformations differed between groups (P = 0.01). Based on MRI, dorsal, and dorso‐lateral hemivertebrae were the cause of spinal cord compression in 5/12 (41.6%) of dogs with neurologic deficits. Findings indicated that a modified human radiographic classification system of vertebral malformations is feasible for use in future studies of brachycephalic “screw‐tailed” dogs. 相似文献