Use of phages for identifying the citrus canker bacterium Xanthomonas campestris pv. citri in Taiwan

Phages CP115 and CP122, which were isolated from canker lesions on grapefruit and Liucheng sweet orange, respectively, showed a high degree of specificity with respect to lysis of test bacterial strains. When used jointly, they lysed 135 (97·8%) out of 138 Xanthomonas campestris pv. citri strains isolated from the canker lesions on leaves, twigs, and fruits of various citrus species, cultivars, and hybrids grown throughout Taiwan, but they did not lyse other X. campestris pathovars and other phytopathogenic bacteria, nor other bacteria isolated from soil, clinical or environmental samples. Of 252 CP115/CP122-sensitive and 78 CP115/CP122-resistant bacterial strains with colony characteristics typical of or similar to those of X. campestris pv. citri , isolated from canker lesions of various citrus plants in diverse growing regions in Taiwan, 250 (99·2%) and 76 (97·4%) strains were pathogenic and non-pathogenic, respectively, when inoculated into Liucheng sweet orange or Mexican lime. Thus, phages CP115 and CP122, when used jointly, appear to be applicable for identifying X. campestris pv. citri in Taiwan.     

Epidural administration of fixed volumes of xylazine and lidocaine for anesthesia of dairy cattle undergoing flank surgery

A modified method for epidural anesthesia in standing cattle undergoing flank surgery in which fixed volumes of xylazine and lidocaine were injected is described, along with results in 18 cattle. A Tuohy needle was inserted into the L1-2 intervertebral space from a dorsal midline approach, positioning of the needle tip in the epidural space was confirmed by use of the hanging drop technique, the needle was slowly advanced 7 to 10 mm to penetrate the epidural fat, and the anesthetic solution was then administered. In the initial 8 cattle, the anesthetic solution consisted of 1 mL of 2% xylazine and 4 mL of 2% lidocaine. However, 1 of these cattle became recumbent prior to surgery. Therefore, the dose of lidocaine was decreased, and in the subsequent 10 cattle, the anesthetic solution consisted of 1 mL of 2% xylazine and 3 mL of 2% lidocaine. Surgery was begun 30 minutes after epidural administration of anesthetic; surgery time ranged from 27 to 276 minutes. Sedation and anesthesia were adequate, except in 1 cow that received the lower dose of lidocaine and became recumbent during suturing of the incision. The modified epidural anesthesia technique with injection of fixed volumes of xylazine and lidocaine appears to be an adequate method for anesthesia of standing cattle undergoing flank surgery.     

Inhibition of growth hormone secretagogue receptor antagonist, [D-Lys-3]-GHRP-6, in adipogenesis of ovine and rat adipocytes

Ghrelin and growth hormone secretagogues receptor (GHS‐R or ghrelin receptor) have been reported as being one of the factors of adipogenesis in adipocytes. To investigate the involvement of ghrelin and GHS‐R in adipocytes, the effect of the GHS‐R antagonist, [D‐Lys‐3]‐GHRP‐6 (His‐D‐Trp‐D‐Lys‐Trp‐D‐Phe‐Lys‐NH₂), on the process of adipogenesis in ovine and rat adipocytes was evaluated. [D‐Lys‐3]‐GHRP‐6 (10^?7 mol/L) significantly inhibited adipogenic differentiation of ovine and rat preadipocytes prepared from adipose tissues. The level of peroxisome proliferator activated receptor (PPAR)‐γ2 mRNA, an adipogenic marker, was decreased during the differentiation of adipocytes treated with [D‐Lys‐3]‐GHRP‐6 for 10 days. Ghrelin stimulated adipogenesis, also causing an increment of glycerol‐3‐phosphate dehydrogenase and upregulation of PPAR‐γ2. Furthermore, the antilipolytic effect of ghrelin was attenuated by treatment with [D‐Lys‐3]‐GHRP‐6 in both types of isolated adipocytes. Overall, the results of the present study highlight that GHS‐R in adipogenesis can be blocked by treatment with [D‐Lys‐3]‐GHRP‐6.     

Allelopathic potential of K21, selected as a promising allelopathic rice

The agronomic characteristics of a newly bred potent allelopathic rice, K21, including morphological appearance, resembled its female parent, Dongjinbyeo, except for 8 days' earlier heading and 9 cm shorter plant height. The water extract of K21 showed a greater inhibitory effect on the shoot and root growth of barnyardgrass than its female parent, but less than the male parent, Kouketsumochi. At the highest extract concentration of 5.0%, the inhibitory effect of K21 on the shoot growth of barnyardgrass was ≈ 64%, similar to its male parent. The dry weight of the barnyardgrass shoot was reduced by 13.0% when grown with K21 and 30.2% when grown with its male parent. There was no inhibitory effect on the shoot dry weight of barnyardgrass when grown with the female parent. The activity of cinnamic acid 4-hydroxylase in K21 was ≈ 1.8-fold higher than that of the female parent, but significantly lower than that of the male parent. The ρ-coumaric acid content in K21 was ≈ 60% higher than that of the female parent, but it was about half of the male parent. The total amount of phenolic compounds in K21 was ≈ 11.5% higher than in the female parent, but about half of the male parent. The results obtained suggest that the newly bred K21 contains desirable allelopathic traits derived from the male parent, Kouketsumochi, and acceptable agronomic traits from its female parent, Dongjinbyeo.     

Multivariate regression analysis of epidural pressure in cattle

OBJECTIVE: To evaluate the effects of growth, maturity, and pregnancy on epidural pressure in cattle. ANIMALS: 50 healthy Holstein cattle (18 heifers, 23 lactating cows, and 9 pregnant nonlactating cows). PROCEDURE: Each of the cattle was restrained in a standing position. Height of the second lumbar vertebra's transverse process (2LTP) and humeral tuberosity (HT) on the right side as well as abdominal girth (AG) were measured in each animal, and body condition score (BCS) was ascertained. Skin caudal to the first lumbar spinous process was aseptically prepared, and anesthetic was injected. After inserting a 16-gauge 120-mm Tuohy needle in the ligamentum flavum, a calibrated pressure transducer was connected to the needle. Then, the needle was introduced into the epidural space, and epidural pressure was recorded. RESULTS: Mean +/- SD residual epidural pressure of heifers (-9.3+/-3.3 mm Hg) was significantly higher than that of lactating (-174+/-5.5 mm Hg) or nonlactating (-14.5+/-2.4 mm Hg) cows. Stepwise regression of 5 variables revealed that only the difference in height between 2LTP and HT (2LTP - HT) in heifers and only BCS in lactating cows were significantly correlated with residual epidural pressure. For all cattle, the optimal equation (R2 = 0.47) describing the relationship was y = -12.7 + 6.3x, - 0.4x2 - 0.1x3, where y is epidural pressure, x1 is BCS, x2 is 2LTP - HT, and x3 is age. CONCLUSIONS AND CLINICAL RELEVANCE: Negative epidural pressure was detected in standing cattle. Growth, maturity, and pregnancy affect epidural pressure in cattle.     

Comparative in vitro effects of closantel and selected β-ketoamide anthelmintics on a gastrointestinal nematode and vertebrate liver cells

PNU-87407 and PNU-88509, β-ketoamide anthelmintics that are structurally related to each other and to the salicylanilide anthelmintic closantel, exhibit different anthelmintic spectra and apparent toxicity in mammals. The basis for this differential pharmacology was examined in experiments that measured motility and adenosine triphosphate (ATP) levels in larval and adult stages of the gastrointestinal nematode, Haemonchus contortus , and in a vertebrate liver cell line and mitochondria. PNU-87407 and PNU-88509 both exhibited functional cross-resistance with closantel in larval migration assays using closantel-resistant and -sensitive isolates of H. contortus . Each compound reduced motility and ATP levels in cultured adult H. contortus in a concentration- and time-dependent manner; however, motility was reduced more rapidly by PNU-88509, and ATP levels were reduced by lower concentrations of closantel than the β-ketoamides. Tension recordings from segments of adult H. contortus showed that PNU-88509 induces spastic paralysis, while PNU-87407 and closantel induce flaccid paralysis of the somatic musculature. Marked differences in the actions of these compounds were also observed in the mammalian preparations. In Chang liver cells, ATP levels were reduced after 3 h exposures to 0.25 μ M PNU-87407, 1 μ M closantel or 10 μ M PNU-88509. Reductions in ATP caused by PNU-88509 were completely reversible, while the effects of closantel and PNU-87407 were irreversible. PNU-87407, closantel and PNU-88509 uncoupled oxidative phosphorylation in isolated rat liver mitochondria, inhibiting the respiratory control index (with glutamate or succinate as substrate) by 50% at concentrations of 0.14, 0.9 and 7.6 μ M , respectively.     

Evaluation of equine cecal motility by ausculation, ultrasonography and electrointestinography after jejunocecostomy

OBJECTIVE: Horses often suffer reduced intestinal motility after jejunocecostomy. Therefore, accurate evaluation of intestinal motility is important for the prevention, diagnosis and treatment of this condition. The purpose of this study was to evaluate intestinal motility in horses after jejunocecostomy using three different methods, i.e. auscultation, ultrasonography and electrointestinography. ANIMALS: Six healthy thoroughbreds were used in this study. They were subjected to jejunocecostomy. PROCEDURE: Bowel sounds in the right paralumbar fossa were assigned a score of 0-3 for intestinal motility evaluation by auscultation, and the number of cecal contractions during a 3-min period were counted by ultrasonography. Electrointestinography (EIG) was used to measure percutaneous potential of the cecum. RESULTS: We identified three specific postoperative periods: the period of reduced intestinal motility (postoperative day 1 to day 2), in which intestinal motility declined, the unstable period (day 3 to day 7), in which intestinal motility partially recovered, and the full recovery period (day 8 to day 31), in which intestinal motility returned to preoperative state. Careful management was found to be especially important during the period of reduced intestinal motility and the unstable period. We found that, in healthy horses that underwent jejunocecostomy, it takes approximately one month for the cecum to return to normal motility patterns observed before surgery. CONCLUSION: We have shown in this study that evaluation of intestinal motility after jejunocecostomy in horses by EIG is more objective and provides more details than evaluation by auscultation or ultrasonography.     

Trade Reorientation and Its Effects on Regional Port Systems: The Korea‐China Link along the Yellow Sea Rim

ABSTRACT Owing to its competitive labor costs, its open‐market policy, and a substantial amount of capital investments, China has become a global manufacturing pole and an export‐based economy replicating the conventional Asian model but on a much wider scale. This is creating acute competition on other Asian export‐based economies such as Korea that have to adapt to the “China effect.” Consequently, many Korean manufacturing companies have repositioned their capital and equipment in China to enlarge their market potential as well as to reduce their production costs. Because Korea is adjacent to China—both are sharing the Yellow Sea Rim—this shift is creating a unique geographical dimension with a high level of functional integration of Sino‐Korean manufacturing supply chains. This transition has also brought substantial changes in the regional logistic network by organizing new flows of raw materials, parts, and final products, most of them along the Yellow Sea Rim. New logistic flows have given substantial influences on regional port competition by creating diverse links. These changes are bringing a reorientation of the regional maritime industry and of the port system.     

NATURAL REGENERATION OF VEGETATION AS AN ALTERNATIVE FOR GREENING SAND-FILLED RECLAIMED LAND IN SINGAPORE

Land reclamation projects have been implemented in Singapore to increase the republic's land area. Not all reclaimed lands have been used to date, and some of those that remain idle have been allowed to regenerate. This paper examines one such sand-filled reclaimed area and studies the pattern of, and factors favouring, the natural regeneration of Casuarina equisetifolia whose seeds come mainly from a row of established mother trees planted by the roadside nearby. Based on the extent of coverage of this species over the reclaimed land and the mean trunk-wood volume build-up after 14 years, natural regeneration of this kind appears to be an effective alternative to the greening of sand-filled reclaimed land, or any derelict land of this nature, at very low cost. © 1997 John Wiley & Sons, Ltd.     

Cryptosporidium parvum infection and management-based risk factors of dairy calves in Taiwan

Cryptosporidiosis is one of the major causes of diarrhea in calves. Cryptosporidium parvum is considered the most important calf diarrhea pathogen in the Cryptosporidium species. Not only could infected calves spread C. parvum, but infected adult cattle could also shed oocysts. The objectives of this study were (1) to investigate the prevalence of C. parvum in dairy herds in Taiwan, including calves, the dams in delivery enclosure, the floor, and the drinking water; (2) to clarify the relationship of diarrhea, management, and C. parvum infection. Twenty dairy herds in Taiwan were selected by random sampling, including 226 calves and 198 dams, and other environmental samples were collected. A questionnaire was filled out by the farm owners to collect information regarding the management of calves and the delivery enclosure. Hierarchical logistic regression was used to analyze the risk factors for C. parvum infection. The prevalence of C. parvum infection in calves was 26.5% (60/226), while in dams, it was 19.7% (39/198). The C. parvum infection in calves increased with environmental contamination of C. parvum and clinical signs of diarrhea, while it decreased with a yard provided in the delivery enclosure. In conclusion, the management of the delivery enclosure appears to be more important for preventing cryptosporidiosis in calves in Taiwan.