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131.

This study was undertaken to provide information on the effect of two levels of dietary fibre (DF) [184 vs. 407 g DF kg-1 dry matter (DM)] on the digestibility of nutrients and energy metabolism in pregnant sows during different stages of pregnancy. The amount of DF in the high-fibre diet was supplied by dried sugar beet pulp (20%) and oats, wheat bran and grass pellets. The intake of metabolizable energy (ME) was similar for both the low-fibre and the highfibre diet, with an average daily intake of 30.74 MJ. Digestibility of DM, organic matter, protein, fat and energy was significantly decreased by a high DF level, but no effect of the diets was observed on the stage of pregnancy. A high fibre level significantly increased the digestibility of DF, indicating that fibre from sugar beet pulp is more fermentable than fibre from cereals. Protein utilization increased during the pregnancy, but at a very low level, indicating that the protein level in diets for pregnant sows could be lower. Inclusion of extra DF in the diet significantly increased the amount of energy excreted as CH4. Heat production was affected by diet, although not significantly (28.77 vs. 29.72 MJ day-1 in the low-fibre and highfibre diets, respectively). The utilization of ME for energy retention was lower for the high-fibre diet as a result of increased hind-gut fermentation. There was similar relation between the net energy of the standard and the high-fibre diet either calculated using the official Danish feed evaluation (0.77) or experimental estimated value (0.81).  相似文献   
132.

Background

Previous research has indicated a breed predisposition to gastric carcinoma in dogs. However, results to date are inconsistent since several studies have failed to prove such a predisposition. Better knowledge of breeds at risk could facilitate early detection of gastric carcinoma in dogs. The aim of the study was to retrospectively investigate the proportion and possible breed predisposition to canine gastric carcinoma using the Norwegian Canine Cancer Register for calculations of proportional morbidity ratios (PMRs) for the period 1998–2009.

Results

Histologically verified tumours recorded in the Norwegian Canine Cancer Register were studied (n = 19,715). A total of 31 (0.16%) cases of canine gastric carcinomas were identified. The median age of affected dogs was 10 years. The most commonly reported clinical signs were vomiting, anorexia, and weight loss. Males had significantly higher odds of gastric carcinoma than females (P = 0.02). The PMR with 95% confidence interval (CI) was calculated for each breed, and a breed predisposition was identified. Individuals of the breeds Tervuren (PMR 56.1), Bouvier des Flandres (PMR 36.5), Groenendael (PMR 34.5), Collie (PMR 26.1), Standard poodle (PMR 7.6), and Norwegian elkhound (PMR 6.1) had a significantly increased risk of developing gastric carcinoma.

Discussion and conclusion

The proportion of cases of gastric carcinoma recorded in the Norwegian Canine Cancer Register was found to be 0.16%, and a breed predisposition was identified. The breed predisposition observed in the current study indicates a genetic susceptibility to gastric carcinoma.  相似文献   
133.
The neuronal voltage-gated N-type calcium channel (Cav2.2) is a validated target for the treatment of neuropathic pain. A small library of anthranilamide-derived ω-Conotoxin GVIA mimetics bearing the diphenylmethylpiperazine moiety were prepared and tested using three experimental measures of calcium channel blockade. These consisted of a 125I-ω-conotoxin GVIA displacement assay, a fluorescence-based calcium response assay with SH-SY5Y neuroblastoma cells, and a whole-cell patch clamp electrophysiology assay with HEK293 cells stably expressing human Cav2.2 channels. A subset of compounds were active in all three assays. This is the first time that compounds designed to be mimics of ω-conotoxin GVIA and found to be active in the 125I-ω-conotoxin GVIA displacement assay have also been shown to block functional ion channels in a dose-dependent manner.  相似文献   
134.
We report the development of a duplex real-time Polymerase Chain Reaction (PCR) for the simultaneous detection and quantification of wheat- and barley-derived DNA. We used a single primer pair to amplify the single-copy gene PKABA1 from wheat and barley, using minor-groove-binding probes to distinguish between the two cereals. The assay was fully specific, and different wheat and barley cultivars exhibited similar Ct values, indicating stability across cultivars with respect to allelic and copy number composition. The limits of detection were 5 and 10 PCR-forming units for wheat and barley, respectively, making the duplex assay as sensitive as other singleplex reference gene systems published. We were able to detect both wheat and barley simultaneously in real food samples, and the duplex assay is considered to be suitable as an endogenous reference gene system for the detection and quantification of wheat and barley in genetically modified organisms (GMO) and other food and feed analyses.  相似文献   
135.
Objectives(1) To investigate heart morphology and function using echocardiography and tissue Doppler imaging (TDI), (2) to determine heart disease prevalence and characteristics, and (3) to assess potential genetic features in a population of Sphynx cats presented for cardiovascular screening.AnimalsA total of 147 echocardiographic examinations, including 33 follow-ups, were performed by trained observers on 114 Sphynx cats of different ages (2.62 ± 1.93 years [0.5–10.0]) from 2004 to 2011.MethodsSphynx cats underwent a physical examination, conventional echocardiography, and, if possible, two-dimensional color TDI.ResultsConventional echocardiographic findings included 75/114 normal (65.8%) and 39/114 (34.2%) abnormal examinations with a diagnosis of either congenital heart diseases (n = 16) or hypertrophic cardiomyopathy (HCM, n = 23). In adult healthy cats, a significant body weight effect was observed for several echocardiographic variables, including end-diastolic left ventricular (LV) free wall (P < 0.01), interventricular septum (P < 0.001), and LV diameter (P < 0.001). Mitral valve dysplasia (MVD) was observed as a single or associated defect in 15/16 cats with congenital heart diseases. A significant increase in HCM prevalence (P < 0.001) was observed according to age. The pedigree analysis of a large family (n = 81) suggested an autosomal dominant mode of inheritance with incomplete penetrance for HCM.ConclusionsBody weight should be taken into account when interpreting values of diastolic myocardial wall thicknesses in Sphynx cats. Additionally, HCM and MVD are two relatively common heart diseases in this feline breed. More pedigree data are required to confirm the inheritance pattern of HCM at the breed level.  相似文献   
136.

Background

The objective of this study was to investigate the association between average daily gain and the number of Lawsonia intracellularis bacteria in faeces of growing pigs with different levels of diarrhoea.

Methods

A longitudinal field study (n = 150 pigs) was performed in a Danish herd from day 29 to 47 post weaning. Every third day all pigs were weighed, subjected to a clinical examination and faecal samples were obtained. Faecal samples were subjected to dry matter determination and absolute quantification by PCR for L. intracellularis and porcine circovirus type 2 (PCV2). Association between average daily gain, faecal dry matter content, numbers of L. intracellularis bacteria and PCV2 genome copies in faeces was investigated in a multilevel mixed-effects linear model.

Results

Increasing numbers of L. intracellularis log10 bacteria/g faeces were significantly associated with decreasing average daily gain (P < 0.001). The association was decreasing with increasing faecal dry matter content (P < 0.01). The number of PCV2 log10 copies/g faeces was not significantly associated with average daily gain of the pigs (P > 0.5).

Conclusion

The results suggest a potential application of a PCR quantifying L. intracellularis in growing pigs. Faecal dry matter content must be taken into consideration in interpretation of such test results.  相似文献   
137.
Fusarium head blight (FHB) caused by Fusarium graminearum (FG) is a destructive disease impacting barley worldwide. The disease reduces the grain yield and contaminates grains with mycotoxins, such as the trichothecene deoxynivalenol (DON). Although the infection mainly affects the grain yield, little is known about its impact on grain structural and biochemical properties. Yet, such information is instrumental to characterize the facets of resistance in the grains. After artificial inoculation of six barley cultivars with FG in a 2 years field test, different levels of symptoms on spikes, of colonisation of grains and of DON content were observed. The infections caused a reduction in grain weight and an average decrease of 10% of the β-glucan content in grains, indicating alterations of grain filling, composition and structure. According to our results, we postulate the presence of two distinct resistance mechanisms in the grain, tolerance to grain filling despite infection as well as the inhibition of mycotoxin accumulation. Differently to wheat, in barley, type IV resistance (tolerance of the grain to infection) is directly linked with type III resistance (resistance against kernel infection). The resistance against toxin accumulation (named type V resistance in wheat) appeared to be independent to all other resistance types. Generally, the resistance was significantly influenced by the environment and by genotype x environment interactions explaining the generally weak stability of resistance in barley. Interestingly, a significant and inverse relationship between DON contamination and β-glucan content in grains suggests that high β-glucan content in grains contributes to type V resistance.  相似文献   
138.
Modeling inter-individual variability in plant populations is a key issue to understand crop heterogeneity and its variations in response to the environment. Being able to describe the interactions among plants and explain the variability observed in the population could provide useful information on how to control it and improve global plant growth. We propose here a method to model plant variability within a field, by extending the so-called GreenLab functional-structural plant model from the individual to the population scale via nonlinear mixed-effects modeling. Parameter estimation of the population model is achieved using the stochastic approximation expectation maximization algorithm, implemented in the platform for plant growth modeling and analysis PyGMAlion. The method is first applied on a set of simulated data and then on a real dataset from a population of 34 winter oilseed rape plants at the rosette stage. Results show that our method allows for a good characterization of the variability in the population with only a limited number of parameters, which is a key point for plant models. Results on simulated data show that parameters associated with a low sensitivity index are inaccurately estimated by the algorithm when considered as random effects, but a good stability of the results can be obtained by considering them as fixed effects. These results open new ways for the analysis of inter-plant variability within a population and the study of plant–plant competition.Supplementary materials accompanying this paper appear online.  相似文献   
139.
140.
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