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131.

Objective

To compare volumes for epidural injection calculated on body weight or the length from sacrococcygeal space to occipital crest in dogs.

Study design

Prospective study.

Animals

A total of 431 dogs weighing mean ± standard deviation (range) 24.6 ± 16.1 (1.3–88.0) kg and with vertebral column length 67.6 ± 38.4 (24.8–119.4) cm.

Methods

Dogs were separated into specific weight groups and body condition scores (BCS; 1–5): small (<10 kg), medium 10 to <25 kg), large (25 to <45 kg) and giant (≥45 kg). Calculations for a lumbosacral epidural dose were 0.2 mL kg?1 and for vertebral column length: 0.05 mL cm?1 (<50 cm), 0.07 mL cm–1 (50 to <70 cm), 0.08 mL cm–1 (70 to <80 cm), and 0.11 mL cm–1 (≥80 cm). A split plot anova (p < 0.05) with weight, length and BCS as factors was used.

Results

A significantly larger volume was calculated for length than for weight in small (p < 0.0001–0.0003, BCS 2–5), medium (p < 0.0001–0.0076, BCS 2–5), and large dogs (p ≤ 0.0007–0.0019, BCS 2,3). In large (BCS 4,5) and giant dogs (BCS 2,3), both calculated volumes were similar. In giant dogs (BCS 4,5), a significantly smaller volume was calculated for length (p ≤ 0.0002–0.0165). Regardless of BCS, small (2.18 versus 1.12), medium (3.99 versus 3.16), and large dogs (7.38 versus 6.82) had larger calculated volumes (mL) for length than for weight (p < 0.0001), whereas giant dogs (10.04 versus 10.91) had smaller calculated volumes.

Conclusions

and clinical relevance Mathematically, the epidural volume of injectate varies with the calculation method and is affected by BCS. Small and medium dogs have larger calculated volumes based on length than on weight, and this difference tends to disappear or revert as size increases.  相似文献   
132.
133.

Objectives

To describe the ventral spinal nerve rami contribution to the formation of the brachial plexus (BP), and to compare ease of performing and nerve staining between three blind techniques for BP blockade in dogs.

Study design

Prospective, randomized, blind study.

Animals

A total of 18 dog cadavers weighing 28.2 ± 9.7 kg (mean ± standard deviation).

Methods

Dogs were randomly assigned to two of three BP treatments: traditional approach (TA), perpendicular approach (PA), and axillary approach (AA). Dye (0.2 mL kg?1) was injected in the left BP using a spinal needle; another BP treatment was used in the right BP. Landmarks (L) included: L1, midpoint between point of the shoulder and sixth cervical (C6) transverse process; L2, scapulohumeral joint; and L3, first rib. For TA, the needle was introduced craniocaudally through L1, medial to the limb and cranial to L3. For PA, the needle was directed perpendicular and caudal to L2, aligned with L1, until cranial to L3. For AA, the needle was directed ventrodorsally, parallel and cranial to L3 until at L1. All BPs were scored for dyeing quality [0 (poor) to 5 (excellent)]. The left BP was dissected for nerve origins. Durbin test was used to compare scores (p < 0.05).

Results

In all dogs, the musculocutaneous nerve originated from C7 and C8; the radial nerve from C8, the first thoracic vertebra (T1) (16/18 dogs) and C7 (2/18); and the median and ulnar nerves from C8, T1 (17/18) and C7 (1/18). Respective raw scores and adjusted scores for the incomplete block design were not significantly different (p = 0.72; ranks TA 16.5, PA 19.0, AA 18.5).

Conclusions and clinical relevance

The musculocutaneous, median, ulnar and radial nerves originate from C7, C8 and T1. Regardless of the technique, knowledge of anatomy and precise landmarks are relevant for correct dye dispersion.  相似文献   
134.
135.
Peppermint is an important aromatic and medicinal plant used across the world in pharmaceutical, cosmetic and food industries. However, there is a lack of agronomic research on this crop which hinders the implementation of best agricultural practice at farm level. Plant analysis, for instance, cannot be used as a tool to implement a suitable fertilizer recommendation program, since sufficiency ranges and crop nutrient removals have not yet been established. Thus, the main objectives of the present work were to assess the response of peppermint to varying nitrogen (N), phosphorus (P), potassium (K) and boron (B) rates, to establish sufficiency ranges from macro, micronutrients and SPAD-readings and to estimate crop nutrient removals in the aboveground biomass. Field trials and pot experiments were conducted from 2013 to 2015 in a wide range of conditions involving 12 N, P, K or B fertilizer trials and a total of 48 cuts of biomass. Nitrogen fertilization increased dry matter yield of peppermint on the vast majority of sampling dates. In contrast, P, K, or B did not produce a significant effect on dry matter yield in any of the experiments. The sufficiency ranges set for macronutrients N, P, K, Ca and Mg are respectively 32.0 – 42.0, 1.2 – 4.5, 10.0 – 30.0, 7.0 – 23.0, and 4.0 – 10.0 g kg?1. Those for micronutrients B, copper (Cu), iron (Fe), zinc (Zn), and manganese (Mn) are respectively 20 – 200, 5 – 25, 100 – 600, 25 – 300, and 30 – 200 mg kg?1. Sufficiency range for SPAD-readings is 45 – 50 SPAD units. All these ranges were established for the commercial harvesting date. The amounts of N, P, K, calcium (Ca), and magnesium (Mg) removed in aboveground biomass are respectively 22.7, 1.6, 26.4, 16.4 and 4.8 kg Mg?1 of dry biomass.  相似文献   
136.
A set of fertilizer experiments were conducted during three growing seasons with the aim of establishing sufficiency ranges and crop nutrient removals for Melissa officinalis L. Critical nutrient concentrations were determined by the Cate–Nelson method or by removing 10% of extreme high and low values, respectively if a positive response to a given nutrient was recorded or not. Sufficiency ranges for macro, micronutrients, and SPAD-readings were set as: 27.0–40.0 g N kg?1; 0.8–2.7 g P kg?1 (May–August); 1.5–3.8 g P kg?1 (September–November); 10.0–25.0 g K kg?1 (May–August); 18.0–32.0 g K kg?1 (September–November); 5.0–25.0 g Ca kg?1; 3.5–8.5 g Mg kg?1; 18–125 mg B kg?1; 5–25 mg Cu kg?1; 75–500 mg Fe kg?1; 20–300 mg Zn kg?1; 30–250 g Mn kg?1; 30–45 SPAD-units. These results will allow laboratories to use plant analysis as an important tool in improving the fertilizer recommendations for this species.  相似文献   
137.
138.
Extraction and electrophoretic analysis of large dsRNAs from plant and fungal tissues has been used successfully to detect RNA viruses infecting plants, fungi, and oomycetes. We modified a previously reported dsRNA extraction protocol and used it to detect a wide variety of plant and putative fungal viruses from infected plant tissues. The modified protocol was used successfully to extract large dsRNAs from 50 to 70 mg of desiccated plant tissues infected with acute and persistent RNA viruses and from plant tissues infected with biotrophic fungi causing rusts and powdery mildew diseases. The protocol proved to be efficient, fast, economic and versatile and requires relatively small amounts of desiccated tissue.  相似文献   
139.
Teak plantation productivity and economic value have risen significantly since 2000; however, teak dieback syndrome in commercial plantations is becoming worse every year. We isolated, characterized and identified the causal agents of teak dieback, based on morphological characteristics in culture and DNA sequencing. The pathogenicity of Lasiodiplodia theobromae and Fusarium proliferatum (separate and together) was confirmed in inoculations of teak elite genotypes, fulfilling Koch's postulates. To our knowledge, this is the first report of L. theobromae and F. proliferatumcausing teak dieback syndrome in Costa Rica.  相似文献   
140.
Eight healthy dogs undergoing elective ovariohysterectomy were anesthetized with a standard protocol and received a low-dose medetomidine constant rate infusion during surgery. Cardiorespiratory parameters, including non-invasive cardiac output, were measured at various times. This protocol resulted in acceptable and stable cardiovascular performance, allowed low isoflurane concentrations, and provided smooth recoveries.  相似文献   
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