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31.
Black-backed jackals (Canis mesomelas) are an abundant mesopredator on farmlands (croplands and rangelands) across South Africa. Given their adaptability in a changing anthropogenic landscape, knowledge of spatial movements can provide important ecological information on the species. We captured, collared and monitored five black-backed jackals in the Midlands of KwaZulu-Natal to determine their home range and habitat use in farmlands. The 95% fixed kernel (95% FK) home range sizes were large, showing a marked seasonal variation in movement. One adult male dispersed 150?km over two seasons (winter and spring) and thereafter settled into a home range that it maintained. Transient home ranges of males and juveniles were larger than resident home ranges. The mean resident home ranges (95% FK) across seasons for adult males, adult female and juvenile males were 11.4 ± 4.3 km2, 5.6 ± 0.36?km2 and 2.15 ± 0.45?km2, respectively. The mean transient home ranges (95% FK) of all the seasons for adult and juvenile males were 1 181.93 ± 575.81 km2 and 104.27 ± 35.64?km2, respectively. Adult jackal preferred croplands in spring, summer and autumn but avoided croplands in winter. Variable habitat use and large home ranges in our study confirmed the species’ ability to adapt to agricultural areas.  相似文献   
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Pain management in dogs and cats has undergone a dramatic evolution in the past decade. Current approaches focus on anticipation and prevention of pain, as well as both pharmacologic and nonpharmacologic management techniques. The veterinary team plays an essential role in educating pet owners about recognizing and managing pain in their pets.  相似文献   
35.
The objectives of the present study were to evaluate the accuracy of broad range 16S rRNA gene PCR compared to bacterial culture for the detection of synovial infection in horses. The study included 57 synovial fluid samples from horses with presumed synovial infection and a control group consisting of 31 synovial fluid samples originating from clinically normal horses and horses with aseptic synovial inflammation. All samples were analysed by 16S PCR with reverse line blot (RLB) hybridisation. Synovial fluid samples were cultured using conventional agar plate methods (APM) and/or blood culture medium (BCM). The results of the study showed a superior detection rate (89.5%) for 16S PCR with RLB. Bacterial culture had lower sensitivity, but highly acceptable detection rates (77.6%) were observed using BCM. APM had very low sensitivity (37.8%) and infection was never detected by plate isolation without positive incubation in BCM. The highest sensitivity (91.8%) for the detection of synovial infection was achieved when the results of incubation in BCM and 16S PCR were combined. For all the tests, the specificity was higher than 90%.  相似文献   
36.
A 9-year-old female Rothschild giraffe (Giraffa camelopardalis rothschildi), weighing approximately 900 kg, at Longleat Safari Park, Wiltshire, UK was presented with dystocia in September 2005. This paper details the surgical and anaesthetic procedures carried out performing a caesarean section to remove a dead male calf and the successful recovery of the giraffe.  相似文献   
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In a cross-sectional study, performed between October 2002 and April 2003 on 55 Danish dairy herds with 6161 predominantly Holstein Friesian cows the prevalence of 9 hoof lesions was determined.

All test-day yields (TDY) of kg energy corrected milk (ECM) in the lactation of diagnosis were recorded. For the purpose of including hoof lesions in a decision support model an attempt was made to aggregate the lesions into digital dermatitis (DD), other interdigital diseases (OID, infectious diseases other than DD) and hoof horn diseases (HHD, related to metabolic disorders and trauma). A division was made based on the stage of lactation in which the lesions were diagnosed; during the first 100 days in milk, between days 101 and 200 and between days 201 and 305. Associations between the presence of hoof lesions at trimming and milk production were analyzed by linear mixed modeling at the cow level, clustered within herd. The data of primiparous cows was analyzed separately from the multiparous cows.

Based on the associations between TDY and the individual lesions aggregated into HHD, this aggregation as initially planned could not be justified and was therefore not maintained. For OID the value of early diagnosis was apparent; an early diagnosis and early treatment (<101 DIM) was associated with either a positive value or a value less negative compared to a diagnosis and treatment in late lactation (201–305 DIM). This pattern was not as clearly present for the other lesions.  相似文献   

38.
This paper discusses the opportunities to combine the efforts of plant geneticists and soil scientists to develop crop varieties adapted to the existing soil conditions and techniques used for production. Such research should result in improved varieties for the best as well as poorest of soil and production situations.  相似文献   
39.
The question of what determines plant community composition is fundamental to the study of plant community ecology. We examined the relative roles of historical land use, landscape context, and the biophysical environment as determinants of plant community composition in regenerating citrus groves in north-central Florida. Results were interpreted in light of plant functional traits. Herbaceous and woody plants responded differently to broad-scale variables; herbs correlated most strongly with surrounding land cover at a scale of 8 km, while the only significant determinant of woody species distributions was local land use history. There were significant correlations between herbaceous species and spatial context, habitat isolation, environmental variables, and historical variables. Partial Mantel tests indicated that each variable provided a unique contribution in explaining some of the variation in the herbaceous dataset. The correlation between woody plants and local historical variables remained significant even with other effects corrected for. In the herbaceous community, species composition was linked to functional traits much as expected from classical theory. While spatial influences in our study system are important for both woody and herbaceous plants, the primary determinant of plant community composition in regenerating citrus groves is historical land use. Our results suggest that the fine-scale mechanisms of local competition, tolerance and facilitation invoked by many classical studies may ultimately be less important than land use history in understanding current plant community composition in regenerating agricultural areas.  相似文献   
40.
Hop with powdery mildew [HPM: caused by Podosphaera macularis (Wallr.) U. Braun & S. Takam.] results in significant losses in hop production by reducing yield and quality. One means of increasing yield and quality is the production of resistant hop lines. Breeding for resistance can be significantly improved and accelerated by use of marker-assisted selection. The objective of this preliminary study was to identify QTLs and markers for genetic resistance to HPM. A bi-parental mapping population between the resistant line “Newport” and susceptible line ‘21110M’. Phenotypic data was scored under controlled greenhouse conditions. Significant differences among offspring were observed and disease resistance did not follow a distinct binomial distribution, suggesting quantitative genetic control. Genotyping-by-sequencing resulted in approximately 375 K SNP markers, which were filtered down to 2263 markers mapped to 10 linkage groups. Interval Mapping identified four QTLs with one on linkage group 1 and three located on linkage group 6. Composite interval mapping identified three QTLs, all located on linkage group 6. Mixed linear models identified 15 markers associated with expression of resistance to HPM. Three of these 15 SNPs were also identified in QTL-CIM analysis. Evaluation of the scaffolds containing the significant SNP markers identified seven putative genes—several of which appear involved in disease resistance in other plant species. The SNP markers identified in this study still require validation in unrelated populations prior to implementation in breeding programs.  相似文献   
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