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1.
While isotopic techniques have largely superseded traditional markers for the determination of the volume of fluid compartments in vivo, they are not always convenient, especially with diarrhoeic animals. A direct comparison was therefore made in week-old calves between Evans blue and radio-iodinated serum albumin as measures of plasma volume and thiocyanate or 24sodium as measures of extracellular fluid space. The correlation coefficients were excellent (1.00, 0.96; P < 0.001) and the calves had plasma and extracellular fluid volumes of 72 +/- 2 and 438 +/- 2 ml kg-1, respectively. The latter value is, though high, typical of young animals and comparable with other data in calves.  相似文献   
2.
Three dogs with multilobular osteochondrosarcoma of the skull were evaluated using magnetic resonance (MR) imaging. Spin echo T1, T2, proton weighted and post contrast T1W images were obtained with a 1.5 Tesla magnet. The MR imaging findings were similar in all three dogs with mixed signal intensities in the T1W, T2W and proton weighted images and fairly large areas of contrast enhancement in the post contrast T1W images. The extent of brain and soft tissue involvement were well delineated and provided useful information concerning surgical planning. MR imaging provided a useful method of evaluating dogs with skull tumors.  相似文献   
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Two groups of six mature brushtail possums (Trichosurus vulpeculu) were housed in two respiration chambers, and their heat production, whole body conductance and lower critical temperatures were measured under a variety of simulated weather patterns. The possums were subjected to ambient temperatures of 30, 20 and 3 degrees C. At 20 and 3 degrees C, the animals were exposed to near still air and light winds (wind speed 0.8 and 6.7 km/h), both with, and without, simulated rain every 8 hours. The lower critical temperature in near still air lies between 7 and 10 degrees C. This temperature increases by about 2, 6 and 8 degrees C respectively for a wind velocity of 6.7 km/h, simulated rain and a combination of the two factors. Weather in New Zealand, especially in the cooler part of the year, will often produce conditions below the lower critical temperature of the thermoneutral zone of possums. This will necessitate significant increases in metabolic rate and hence food consumption or mobilisation of body fat reserves, which if not sustainable will result in the death of possums. Field studies have shown that this is often the case in the wild. It is proposed that this stress may be sufficient to decrease the resistance (especially cell-mediated immunity) of some possums and allow acceleration of the disease process in those infected with Mycobacterium bovis.  相似文献   
5.
1. The performance of six commercial stocks of laying hens fed on a diet composed of home‐produced foodstuffs, not usually used for human consumption, was compared with that of birds fed on a conventional diet.

2. The experimental diet was calculated to be low in energy and methionine and high in fibre by conventional standards. Birds ate up to 12% more of this diet, but the calculated intakes of energy and methionine were less than those of the corresponding controls.

3. White stocks fed on the experimental diet produced seven eggs less per bird than controls while the production of brown stocks was essentially unaffected.

4. The gross efficiency of energy utilisation for egg production was better with the experimental diet.  相似文献   

6.
The ability of nine strains of avian infectious bronchitis virus (IBV) to induce chicken interferon has been investigated using Semliki Forest virus for the tests. The Beaudette, H120 and Connecticut 46 strains induced interferon in the allantoic fluids of embryonated hens' eggs, the highest titre (1 : 30) being associated with Beaudette; but these as well as the Massachusetts M-41 and H52 strains failed to yield interferon in primary monolayer cultures of chick kidney cells as did all nine strains in organ cultures of chick embryo trachea. None of six strains of IBV investigated was susceptible to the inhibitory effects of chicken interferon.  相似文献   
7.
Morphological, cytological and molecular evidence is presented which confirms that the frosty pod rot pathogen of cocoa, formerly classified as the mitosporic fungus Moniliophthora roreri (Deuteromycota), belongs to the hymenomycetous genus Crinipellis (Basidiomycota) and that two varieties should now be recognized: Crinipellis roreri var. roreri and the new variety C. roreri var. gileri . The latter was collected on Theobroma gileri , an endemic tree of submontane forests in north-west Ecuador, and can be distinguished from Ecuadorian and Peruvian isolates from cocoa ( T. cacao ) on the basis of spore morphology, incompatibility and nucleotide sequence data. As with var. roreri , meiosis is shown to occur within the dispersive and infective spore stage of var. gileri and these meiospores are interpreted to represent a much modified probasidium. In addition, in a field inoculation experiment, an isolate from T. gileri proved to be noninfective to cocoa pods when compared with positive control strains isolated from T. cacao in western Ecuador and T. bicolor in eastern Ecuador. It is concluded that var. gileri is the vestigial progenitor of the frosty pod rot pathogen of cocoa, with a host range and distribution restricted to T. gileri in the mesic forests of north-west South America.  相似文献   
8.
Fusarium circinatum is the causal agent of pitch canker, a destructive disease that threatens natural and planted pine forests around the world. Although pitch canker has caused problems in Spain and Portugal, concerning Europe as a whole, the fungus is not established across the pine distribution area. Its dispersion by wind and/or insect vectors could nevertheless play a role in the colonization of currently uninfected stands. It is therefore crucial to develop monitoring tools for its detection. To this end, we assessed the molecular detection of the pathogen in environmental samples of bark beetles and passive spore traps, collected in two infected Pinus radiata plantations in Basque country, Spain. The spread pattern of F. circinatum was assessed by an experimental design that included insect and spore traps installed at the centre, at the edge and outside the plots. Our results showed that F. circinatum was detected in both types of samples, at almost all collection dates. In both type of samples, positive detections were mainly found at the centre of the plots, a lower proportion at the edge, and very few outside. This suggests that long‐distance dispersion of Fusarium circinatum does not rely on wind spore dispersal neither on insect flight. Our study also shows that molecular methods are a powerful tool to monitor the pathogen in environmental samples.  相似文献   
9.
Most traits in animal breeding, including feed efficiency traits in pigs, are affected by many genes with small effect and have a moderately high heritability between 0.1 and 0.5, which enables efficient selection. Since the microbiota composition in the gastrointestinal tract is also partly heritable and was shown to have a substantial effect on feed efficiency, the host genes affect the phenotype not only directly by altering metabolic pathways, but also indirectly by changing the microbiota composition. The effect of the microbiota composition on the breeding value of an animal is the conditional expectation of its breeding value, given the vector with microbiota frequencies, that is The breeding value of an animal can therefore be decomposed into a heritable contribution that arises from an altered microbiota composition and a heritable contribution that arises from altered metabolic pathways within the animal, so Instead of selecting for breeding value , an index comprising the two components and with appropriate weights, that is , can be used. The present study shows how this breeding strategy can be applied in pig genomic selection breeding scheme for two feed efficiency traits and daily gain.  相似文献   
10.
Imerslund-Gräsbeck syndrome is an autosomal recessive disease reported only in certain pure-breed dogs. An 18-month-old, male neutered beagle cross-breed was presented for evaluation of severe lethargy, progressive weakness and anorexia. Main clinicopathological findings included low body condition score (2.5/9), severe muscle atrophy, several neurological abnormalities, mild normochromic, normocytic, non-regenerative anaemia, severe hypocobalaminemia and mild proteinuria. Extensive diagnostic tests ruled out most of differential diagnoses for the aforementioned clinicopathological abnormalities and genetic evaluation showed that the dog was heterozygous for two previously described mutations affecting the CUBN gene, the beagle and the border collie variants. The dog showed an excellent clinical response to oral cobalamin supplementation with no relapse after 4 months. In conclusion, this case creates awareness that Imerslund-Gräsbeck syndrome should be considered even in mixed-breed dogs with compatible clinical signs and that two different pathogenic CUBN mutations in compound heterozygosity can lead to a typical Imerslund-Gräsbeck syndrome phenotype.  相似文献   
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