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91.
A seven‐year‐old, entire male, American Staffordshire bull terrier was diagnosed with chronic solar dermatitis and basal cell carcinoma, based on physical examination, cutaneous cytology and histopathology. Immunohistochemistry revealed that the tumour cells did not express p53. To the authors’ knowledge this is the first reported case of canine basal cell carcinoma developing as a complication of chronic solar dermatitis.  相似文献   
92.
An AB programme restricted to 14 days through the use of mated, 135 were treated after selection on pre-mating oestrus dates or rectal examination. Treatment was administered on the 6th day of mating. Untreated cows were inseminated, on detection of oestrus, throughout the 14 days. Nine of 135 treated cows were inseminated within 48 hours, 50 at 72 hours only, 75 at both 72 and 96 hours and one at 96 hours after treatment. All cows in season were inseminated, irrespective of recent insemination. Prolonged and split heats, and short cycles (less than 14 days), occurred in treated and untreated cows.

AB conceptions confirmed in those cows retained in the herd were 623% of untreated cows (66.9% of those which were inseminated) and 69.1% of treated.

The conceptions achieved in this abbreviated AB programme are equal to those normally achieved after 7 weeks of AB. Mating management is discussed; the release of labour from AB involvement 4 weeks earlier than usual is a major advantage of this technique.  相似文献   
93.
94.
The reproductive tract of each of 122 cows was palpated transrectally by a veterinarian on the day before they were slaughtered, to obtain estimates of ovarian size and to identify palpable ovarian structures. Reproductive tracts were then retrieved post mortem. Ovarian volumes were recorded and compared with in vivo size scores (coded 1–5; 1 being the smallest). Ovarian volumes averaged 4.0 ml (score l), 7.0 ml (2), 10.0 ml (3), 12.9 ml (4) and 15.9 ml (5). There was a linear increase in ovarian volume of 3.0 ± 0.1 ml per score unit (r2 = 0.792). The curvilinear regression included a significant quadratic term (p<0.05), but only accounted proportionally for an additional 0.003 of the sums of squares. Ovarian size score was about proportional to volume and could be used as a non-surgical technique to measure ovarian volume in live cattle.  相似文献   
95.
96.
Abstract

Since its emergence in Africa in 2016, fall armyworm (FAW) has spread rapidly and poses a severe threat to the food security and livelihood of millions of smallholder farmers in the continent. Using survey data from Ghana and Zambia, we examined FAW prevention and control methods implemented by farm households and their impacts on maize output and household consumption of self-produced maize. The main control methods used included pesticide application and handpicking of larvae, while access to information on FAW was a key driver behind the implementation of the control methods. Results from an endogenous switching regression showed that the implementation of a FAW management strategy significantly enhanced maize yield and households’ own maize consumption. When disentangling the impacts of the main control methods, we found that the combination of pesticide application and handpicking of larvae produced the highest yield gain of 125%. We concluded that the current interventions put in place by farmers to tackle FAW infestations are providing positive outcomes, but successful management of the pest will require more actions, including raising awareness to enhance the adoption of control interventions and exploring other control options.  相似文献   
97.
Differences in the cytological interpretation of bronchoalveolar lavage fluid (BALF) after cytospin preparation (CP) or manual smearing of pelleted cells preparation (MSP) were investigated in client-owned dogs and cats with inflammatory or infectious lower respiratory disease. Bronchoalveolar lavage fluid from healthy cats was also examined. With MSP, cell lysis was more frequently observed, and cellular distribution was more heterogeneous throughout the slide. When samples from healthy and diseased animals were considered together, a significantly greater percentage of neutrophils was seen on CP than on MSP slides (P<0.002). Cytospin preparations were considered of better quality in all individual comparisons. Cytospin preparation is advised in the evaluation of BALF with low total cell count. When only MSPs are evaluated, clinicians should be aware that differential neutrophil counts may underestimate the counts found on CP slides.  相似文献   
98.
BACKGROUND: Canine leishmaniasis (CanL) is a common cause of epistaxis in dogs residing in endemic areas. The pathogenesis of CanL-associated epistaxis has not been fully explored because of the limited number of cases reported so far. HYPOTHESIS: Epistaxis in CanL could be attributed to more than 1 pathomechanism such as hemostatic dysfunction, biochemical abnormalities, chronic rhinitis, and coinfections occurring in various combinations. ANIMALS: Fifty-one dogs with natural CanL. METHODS: The allocation of 51 dogs in this cross-sectional study was based on the presence (n = 24) or absence (n = 27) of epistaxis. The potential associations among epistaxis and concurrent infections (Ehrlichia canis, Bartonella spp., and Aspergillus spp.), biochemical and hemostatic abnormalities, and nasal histopathology were investigated. RESULTS: Hypergammaglobulinemia (P= .044), increased serum viscosity (P= .038), decreased platelet aggregation response to collagen (P= .042), and nasal mucosa ulceration (P= .039) were more common in the dogs with epistaxis than in those without epistaxis. The other significant differences between the 2 groups involved total serum protein (P= .029) and gamma-globulin (P= .013) concentrations, which were higher, and the percentage platelet aggregation to collagen, which was lower (P= .012) in the epistaxis dogs. CLINICAL IMPORTANCE: CanL-associated epistaxis appears to be the result of multiple and variable pathogenetic factors such as thrombocytopathy, hyperglobulinemia-induced serum hyperviscosity, and nasal mucosa ulceration.  相似文献   
99.
Mating type, in vitro sensitivity to the phenylamide fungicide metalaxyl, and mitochondrial (mtDNA) haplotype were determined in some or all of 618 isolates of Phytophthora infestans from the years between 1978 and 1995. A2 mating type occurred infrequently in most but not all years and insensitivity to metalaxyl increased over time. After 1982, the mtDNA Ib haplotype was largely replaced (except for one isolate in 1986 and one in 1995) by two new haplotypes, Ia and IIa. Type Ia was much more common than type IIa.Approximately one quarter of these isolates (165) were compared using two components of fitness associated with aggressiveness (infection frequency × number of sporangia per lesion) on detached leaves of cultivars Maris Piper, Cara and Stirling, which were chosen as exhibiting increasing levels of race non-specific resistance. Isolates were compared with three standard isolates of low, intermediate or high aggressiveness, and the data standardised for comparison between experiments. On cvs. Cara and Stirling, but not on Maris Piper, mtDNA Ia and IIa haplotypes were more aggressive than type Ib in several separate experiments. Similarly, metalaxyl sensitive phenotypes were more aggressive than insensitive phenotypes on Cara and Stirling but not on Maris Piper. The displacement of mtDNA type Ib by types Ia and IIa over this period may have been a result of the lower aggressiveness and lack of complete insensitivity to metalaxyl in type Ib isolates.  相似文献   
100.
Urban trees are frequently planted with their root collars and structural roots buried well below soil grade, either because of planting practices, nursery production practices, or both. These deeply planted structural roots can impair tree establishment and are thought to reduce tree growth, lifespan, and stability, although research has provided few and contradictory results on these questions to date. This study examines container-grown (55 L) Turkish hazel trees (Corylus colurna L.), planted either at grade, 15 cm below grade, or 30 cm below grade into a well-drained silt loam soil, over nearly 8 years. Five years after planting, in 2004, remediation treatments (root collar excavations) were performed on two replicates of each below-ground treatment. Subsequently, all trees were subjected to flooding stress by being irrigated to soil saturation for approximately 6 weeks. In 2006, flooding stress was repeated. Trees root systems were partially excavated in 2007, and root architecture was characterized. Deep planting did not affect trunk diameter growth over 8 years. Survival was 100% for the first 5 years; however, one 30 cm below grade tree died after flooding in 2004 and another died after the 2006 flooding. Photosynthesis was monitored during the 2004 flooding and all trees experienced decline in photosynthetic rates. There was an apparent slight delay in the decline for trees with excavated root collars and those planted at grade. Girdling roots reduced trunk taper and occurred primarily on unremediated trees planted 30 cm below grade.

Selected individual roots were excavated and followed from the root ball and were observed to gradually rise to the upper soil regions. Analysis of roots emerging from excavation trench faces indicated that vertical root distribution at approximately 1.25 m from the tree trunks was the same regardless of planting depth. Longterm consequences of planting below grade are discussed.  相似文献   

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