Spleen index and mannose-binding lectin levels in four channel catfish families exhibiting different susceptibilities to Flavobacterium columnare and Edwardsiella ictaluri     

LaFrentz BR  Shoemaker CA  Booth NJ  Peterson BC  Ourth DD 《Journal of aquatic animal health》2012,24(3):141-147

Edwardsiella ictaluri and Flavobacterium columnare are two bacterial pathogens that affect channel catfish Ictalurus punctatus aquaculture. At the Catfish Genetics Research Unit (U.S. Department of Agriculture, Agricultural Research Service), some progress has been made in selectively breeding for resistance to E. ictaluri; however, the susceptibility of these families to F. columnare is not known. Our objectives were to obtain baseline information on the susceptibility of channel catfish families (maintained as part of the selective breeding program) to E. ictaluri and F. columnare and to determine whether the spleen index and plasma levels of mannose-binding lectin (MBL) are predictive indicators of susceptibility to these pathogens. Four channel catfish families were used: family A was randomly chosen from spawns of fish that were not selectively bred for resistance; families B, C, and D were obtained after selection for resistance to E. ictaluri. All four families were immersion challenged with both bacterial pathogens; the spleen index and plasma MBL levels of unchallenged fish from each family were determined. Mean cumulative percent mortality (CPM) after E. ictaluri challenge ranged from 4% to 33% among families. Families A and B were more susceptible to F. columnare (mean CPM of three independent challenges = 95% and 93%) than families C and D (45% and 48%), demonstrating that there is genetic variation in resistance to F. columnare. Spleen index values and MBL levels were not significantly different, indicating that these metrics are not predictive indicators of F. columnare or E. ictaluri susceptibility in the four tested families. Interestingly, the two families that exhibited the highest CPM after F. columnare challenges had the lowest CPM after E. ictaluri challenge. Further research on larger numbers of families is needed to determine whether there is any genetic correlation between resistance to E. ictaluri and resistance to F. columnare.  相似文献   

Re-examination of the role of the Brucella melitensis HtrA stress response protease in virulence in pregnant goats.     

R M Roop  R W Phillips  S Hagius  J V Walker  N J Booth  W T Fulton  M D Edmonds  P H Elzer 《Veterinary microbiology》2001,82(1):91-95

Based on previously reported studies describing the experimental infection of pregnant goats with B. melitensis strain RWP5, we proposed that the HtrA protease plays an important role in the virulence of B. melitensis in its natural ruminant host. Subsequent studies, however, have shown that RWP5 is actually an htrA cycL double mutant. In order to definitively evaluate the role of the B. melitensis htrA in virulence, we constructed an authentic htrA mutant and examined this strain in pregnant goats. The findings of these studies indicate that the contribution of the htrA gene product to the virulence of B. melitensis in its natural host is not as great as was previously proposed.  相似文献   

Comparing Two Ground-Cover Measurement Methodologies for Semiarid Rangelands     

Keith T. Weber  Fang Chen  D. Terrance Booth  Mansoor Raza  Kindra Serr  Bhushan Gokhale 《Strength and Conditioning Journal》2013,66(1):82-87

The limited field of view (FOV) associated with single-resolution very-large-scale aerial (VLSA) imagery requires users to balance FOV and resolution needs. This balance varies by the specific questions being asked of the data. Here, we tested a FOV-resolution question by comparing ground cover measured in the field with the use of point-intercept transects with similar data measured from 50-mm-per-pixel (mmpp) VLSA imagery of the same locations. Particular care was given to spatial control of ground and aerial sample points from which observations were made, yet percent cover estimates were very different between methods. An error budget was used to calculate error of location and error of quantification. These results indicated location error (43.5%) played a substantial role with significant quantification error (21.6%) also present. We conclude that 1) although the georectification accuracy achieved in this project was actually quite good, the level of accuracy required to match ground and aerial sample points represents an unrealistic expectation with currently available positioning technologies, 2) 50-mmpp VLSA imagery is not adequate for accurate species identification or cover assessments of plant functional groups, and 3) the balance between resolution and FOV needs is best addressed by using multiple cameras to acquire nested imagery at multiple VLSA resolutions simultaneously. We recommend ground cover be measured from 1-mmpp imagery and that the imagery be nested in lower-resolution, larger FOV images simultaneously acquired.  相似文献   

Investigations on the efficacy of routinely used phenotypic methods compared to genotypic approaches for the identification of staphylococcal species isolated from companion animals in Irish veterinary hospitals     

Lisa Geraghty  Mary Booth  Neil Rowan  Andrew Fogarty 《Irish veterinary journal》2013,66(1):7

Background

Identification of Staphylococci to species level in veterinary microbiology is important to inform therapeutic intervention and management. We report on the efficacy of three routinely used commercial phenotypic methods for staphylococcal species identification, namely API Staph 32 (bioMérieux), RapID (Remel) and Staph-Zym (Rosco Diagnostica) compared to genotyping as a reference method to identify 52 staphylococcal clinical isolates (23 coagulase positive; 29 coagulase negative) from companion animals in Irish veterinary hospitals.

Results

Genotyping of a 412 bp fragment of the staphylococcal tuf gene and coagulase testing were carried out on all 52 veterinary samples along with 7 reference strains. In addition, genotyping of the staphylococcal rpoB gene, as well as PCR-RFLP of the pta gene, were performed to definitively identify members of the Staphylococcus intermedius group (SIG). The API Staph 32 correctly identified all S. aureus isolates (11/11), 83% (10/12) of the SIG species, and 66% (19/29) of the coagulase negative species. RapID and Staph-Zym correctly identified 61% (14/23) and 0% (0/23) respectively of the coagulase-positives, and 10% (3/29) and 3% (1/29) respectively of the coagulase-negative species.

Conclusions

Commercially available phenotypic species identification tests are inadequate for the correct identification of both coagulase negative and coagulase positive staphylococcal species from companion animals. Genotyping using the tuf gene sequence is superior to phenotyping for identification of staphylococcal species of animal origin. However, use of PCR-RFLP of pta gene or rpoB sequencing is recommended as a confirmatory method for discriminating between SIG isolates.  相似文献   

Aplysia gigantea toxicosis in 72 dogs in Western Australia     

RE Peacock  G Hosgood  KL Swindells  L Smart 《Australian veterinary journal》2013,91(7):292-295

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Skeletal deformities associated with nutritional congenital rickets in newborn lambs     

KE Dittmer  RE Morley  RL Smith 《New Zealand veterinary journal》2013,61(1):51-55

Abstract

CASE HISTORY: A group of 545 pregnant rising 2-year-old Coopdale ewes on a Southland sheep farm were grazed over winter on a fodder beet (Beta vulgaris) crop. Subsequently, 45 out of approximately 750 lambs were born with a variety of skeletal deformities, including shortened limbs, varus and valgus angular limb deformities, palmar grade stance and cranial bowing of the carpus. Analysis of the crop showed the fodder beet contained a low percentage of phosphorus. In addition, 60 out of 460 rising 2-year-old ewes that had been grazed on the fodder beet crop as 1-year-olds had incisor abnormalities and malocclusion.

PATHOLOGICAL FINDINGS: Two affected lambs (1-day-old and 3-days-old) with representative clinical signs examined postmortem were found to have markedly enlarged costochondral junctions, and noticeably enlarged long bone metaphyses. In addition, one lamb had a dense band of metaphyseal sclerosis beneath the physes of all long bones examined. Histopathological findings included small islands and columns of chondrocytes and eosinophilic cartilage matrix present in the metaphysis. Metaphyseal trabeculae were disorganised and often lined by accumulations of pale pink osteoid; similar pale pink osteoid was also present in the cortices. Unerupted molar teeth in the affected lambs lacked a layer of enamel, and the dentine was irregular with globular basophilia.

DIAGNOSIS: The gross and histopathological lesions were consistent with a diagnosis of rickets.

CLINICAL RELEVANCE: Nutritional congenital rickets has not been previously diagnosed in sheep, but is a recognised disease of human infants with vitamin D deficient mothers. The rickets in affected lambs was most likely associated with phosphorus deficiency as a result of the pregnant ewes grazing fodder beet during gestation. While vitamin D deficiency was not definitively ruled out in these cases, practitioners are alerted to the possible effects of feeding phosphorus-deficient fodder beet to ewes for long periods during gestation and to 1-year-old sheep during important growth periods.  相似文献   

Dystocia in beef heifers: A review of genetic and nutritional influences     

RE Hickson  ST Morris  PR Kenyon  N Lopez-Villalobos 《New Zealand veterinary journal》2013,61(6):256-264

Breeding beef heifers for the first time at 15 months of age has potential to increase the efficiency of the beef breeding-cow herd. An increased incidence of dystocia in heifers calving at 2 years of age, compared to mature cows, is a major reason many farmers in New Zealand have not adopted the practice. The predominant type of dystocia affecting 2-year-old heifers is feto-maternal disproportion, a condition in which the fetus is too large relative to the size of the heifer's pelvis. Reducing birthweight of the calf is a means of reducing the incidence of dystocia. Birthweight and length of gestation are determined by genotype of the calf, maternal genetic effects and environmental effects.

Bulls with low estimated breeding values for birthweight have been selected for mating heifers; however, the positive genetic correlation between birthweight and mature weight meant that the progeny of these bulls tended to be lighter at finishing, making them less desirable in the beef industry. The genotype of the dam also plays a role in determining the risk of dystocia; the maternal ability of the dam to nurture the fetus influences birth- weight, and the dam's genetic potential for growth influences the size of her pelvic area. Heavy heifers tend to produce high- birthweight calves, counteracting the reduction in the incidence of dystocia resulting from the larger pelvis in larger heifers.

Manipulating feeding level during pregnancy offers an alternative method for manipulating the birthweight of calves. Little is known about the effects of nutrition in early gestation on placental development or birthweight of calves. No differences in the birthweight of calves have been observed in response to variation in feeding in mid-pregnancy, and variable responses in birthweight and the incidence of dystocia to feeding in the third trimester of pregnancy have been reported. Differences in birthweight have not always resulted in differences in the incidence of dystocia, primarily due to differences in liveweight of the heifer also induced by feeding regimens. Variability in the incidence of dystocia in response to feeding level in the third trimester of pregnancy makes it difficult to make recommendations for the feeding of heifers at this stage of gestation. More research is needed into the effects of nutrition in early gestation on fetal and placental development in cattle.  相似文献   

The Expression of Aryl Hydrocarbon Receptor in Porcine Ovarian Cells     

O Jablonska  RE Ciereszko 《Reproduction in domestic animals》2013,48(5):710-716

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Determining contemporary and historical sediment sources in a large drainage basin impacted by cumulative effects: the regulated Nechako River,British Columbia,Canada     

Gateuille  David  Owens  Philip N.  Petticrew  Ellen L.  Booth  Barry P.  French  Todd D.  Déry  Stephen J. 《Journal of Soils and Sediments》2019,19(9):3357-3373

Purpose

Sediment dynamics in most large river basins are influenced by a variety of different natural and anthropogenic pressures, and disentangling these cumulative effects remains a challenge. This study determined the contemporary and historical sources of fine-grained (<?63-μm) sediment in a large, regulated river basin and linked changes in sources to activities in the basin. The river has seen declines in chinook salmon, sockeye salmon, and the endangered Nechako white sturgeon populations, and sediment (both fine-grained and sands) transport and deposition have been identified as potential causes of these declines.

Materials and methods

Samples of suspended sediment and potential source materials were collected from numerous sites distributed throughout the upper Nechako River Basin in British Columbia, Canada. A floodplain sediment core was also collected in order to reconstruct sediment sources over the last ~?70 years. Discriminating fingerprint properties were used within the MixSIAR model to apportion sources among sub-basins and land-use types. Results were compared to records of precipitation and Nechako River discharge trends, and to changes in landscape development.

Results and discussion

Contributions from the erosion of channel banks dominated the suspended sediment load at most sites. Changes in sediment sources during the 2015 field season reflected snowmelt and patterns of water release from the Nechako Reservoir that affected the sediment-carrying capacity of tributaries and the Nechako River main stem. Spatial variations in 2015 also reflected the distribution of land use (e.g., forested or agricultural land) as well as topography (e.g., slope steepness). Over the last ~?70 years, variations in sediment sources and the characteristics of the sediment (e.g., organic matter content and particle size composition) were linked to the construction of the Kenney Dam (operational in 1954) and the impacts of deforestation by the forestry and agricultural industries. Superimposed on these have been wildfires and a major mountain pine beetle infestation leading to higher erosion rates in the affected areas.

Conclusions

The sediment source fingerprinting technique, in combination with historical information on the hydrometeorology and the land use and river management in the basin, has provided valuable information with which to understand sediment dynamics in the Nechako River Basin. Such an approach can help to disentangle how large river systems respond to a combination of natural and anthropogenic pressures.

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Penile haemangiosarcoma in a breeding stallion          下载免费PDF全文

D. P. Byrne  L. Woolford  T. M. Booth 《Equine Veterinary Education》2016,28(6):304-309

A 9‐year‐old Arab stallion was presented for haematuria and a haemorrhagic mass on the urethral process of the penis. Clinical examination and surgical excision suggested a tumour of the penis, histologically confirmed as a haemangiosarcoma. The stallion was successfully treated with surgical excision; however, successful breeding has not been achieved thus far (28 months). To the authors' knowledge, haemangiosarcoma of the equine penis has not previously been described.  相似文献