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31.
Armillaria root rot symptoms were observed on native Protea and Leucadendron (Proteaceae) species in Kirstenbosch Botanical Gardens in the Western Cape Province of South Africa. Intergenic spacer (IGS)-1 polymerase chain reaction (PCR) restriction fragment-length polymorphism (RFLP) profiling indicated the presence of at least two Armillaria species. The profiles of two isolates were identical to those of A. mellea s. str., originating in Europe. Phylogenetic analyses incorporating internal transcribed spacer (ITS) and IGS-1 sequence data identified the remaining isolates as closely related to A. calvescens , A. gallica , A. jezoensis and A. sinapina . These isolates displayed mating compatibility with A. gallica. From the RFLP profiles, sequencing results and sexual compatibility studies, it is concluded that the two species on Proteaceae in Kirstenbosch represent A. mellea and A. gallica . These are northern hemisphere fungi that have apparently been accidentally introduced into South Africa. This is the second report of Armillaria being introduced into South Africa. The introduction probably occurred early in the colonization of Cape Town, when potted plants from Europe were used to establish gardens.  相似文献   
32.
Castration is a routine procedure performed on beef and dairy operations in the United States. All methods of castration cause behavioral, physiologic, and neuroendocrine changes associated with pain. The American Veterinary Medical Association and the American Association of Bovine Practitioners recommend that anesthesia and analgesia be administered during castration. The objective of this study was to evaluate the effectiveness of bupivacaine liposome suspension, a novel, long-acting, local anesthetic formulation administered as a nerve block at castration. The authors chose to investigate this novel formulation as an alternative to the current industry standards using lidocaine nerve blocks alone or in combination with meloxicam. Thirty male Holstein calves, 16 to 20 wk of age, were enrolled and randomly assigned to one of the four treatment groups prior to surgical castration: 1) bupivacaine liposome suspension block + oral placebo (BUP), 2) lidocaine block + oral placebo (LID), 3) lidocaine block + oral meloxicam (1 mg/kg) (LID + MEL), and 4) saline block + oral placebo (CON). Biomarkers were collected at −24 h and from 0 to 120 h post-castration and included infrared thermography, pressure mat gait analysis, chute defense and behavior scoring (pain and activity), and blood sampling for serum cortisol and prostaglandin E2 metabolites (PGEMs). Responses were analyzed using repeated measures, with calf nested in treatment as a random effect, and treatment, time, and their interaction designated as fixed effects. The results from pressure mat gait analysis show that the CON had a shorter front limb stance time from baseline (−8.73%; 95% confidence interval [CI]: −24.84% to 7.37%) compared with BUP and LID + MEL (>5.70%; 95% CI: −22.91% to 23.79%) (P < 0.03). The CON tended to have an increase in front limb force from baseline (6.31%; 95% CI: −1.79% to 14.41%) compared with BUP, LID, and LID + MEL (<−5.06%; 95% CI: −14.22% to 0.95%) (P < 0.04). The CON displayed higher counts of hunched standing (2.00; 95% CI: 1.68 to 2.32) compared with LID + MEL (1.43; 95% CI: 1.13 to 1.72) (P = 0.05). The CON had higher cortisol concentrations at 24 h (7.70 ng/mL; 95% CI: 1.52 to 13.87 ng/mL) relative to BUP (3.11 ng/mL; 95% CI: −2.56 to 8.79 ng/mL) (P = 0.002). At 4 and 24 h, LID + MEL had lower PGEM concentrations from baseline (−32.42% and −47.84%; 95% CI: −78.45% to −1.80%) compared with CON (27.86% and 47.63%; 95% CI: 7.49% to 82.98%) (P < 0.02). The administration of bupivacaine liposome suspension as a local anesthetic block at the time of castration was as effective at controlling pain as a multimodal approach of lidocaine and meloxicam.  相似文献   
33.
A preliminary evaluation of annual, wintergreen pastures using weaned lambs in the eastern Cape sourveld. Animal production and feed availability on oats, vetch and oats/vetch pastures were evaluated under continuous grazing, at three stocking rates, using weaned lambs. The oats and oats/vetch mixture generally produced significantly more available above‐ground phytomass (AAP) than the vetch pasture. No significant differences in AAP or average daily gain (ADG) were measured between stocking rates on the different pastures. The levels of food availability and animal production obtained with the different pastures indicate that oats, vetch and an oats/vetch mixture can be used as annual, wintergreen pastures in the eastern Cape sourveld. However, the stocking rates that were implemented were too low to determine the production potential of the different pastures and an evaluation of the pastures at higher stocking rates is recommended before any recommendation on optimal stocking rates can be made.  相似文献   
34.
An epithelial cell line, designated JS-15,4, has been established in culture from jaagiekte lesions and subcultured in vitro for almost 2 years. It exhibits morphological and other features of transformed cells and has been shown by electron microscopy to consist of type B ovine alveolar epithelial cells. Jaagiekte was successfully transmitted to 3 new-born lambs by the intratracheal injection of cells following immunosuppressive treatment with either anti-thymocyte immunoglobulin alone or combined with anti-macrophage immunoglobulin. Incubation periods as short as 10 weeks were recorded. Evidence was also obtained that natural transmission may result from the inhalation of viable cells.  相似文献   
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At a recent workshop, experts discussed the benefits, risks, and research priorities associated with using genetically manipulated insects in the control of vector-borne diseases.  相似文献   
39.
Six species of adult oribatid mites (Galumna racilis, Kilimabates pilosus, Kilimabates sp., Scheloribates fusifer, Muliercula ngoyensis and Zygoribatula undulata) and two immature stages belonging to the superfamilies Galumnoidea and Ceratozetoidea were isolated from a lawn (mixed Pennisetum and Cynodon spp.) at Onderstepoort Veterinary Institute, South Africa. The mites were subsequently used in an infection trial using Moniezia expansa eggs. Tapeworm cysticercoids were recovered in G. racilis, K. pilosus, Kilimabates sp., S. fusifer, M. ngoyensis and Z. undulata, as well as in immatures of Ceratozetoidea.The percentage of infected mites was 7,6, 6,3, 16,4, 66,7, 57,1, 60,0 and 46,7% respectively. Immatures of Galumnoidea did not become infected. The highest number of cysticercoids isolated from one individual was six from an adult S. fusifer.  相似文献   
40.
In most monogamous breeding systems males demonstrate a high degree of paternal care. With the significant costs of this parental investment, it is clearly in the interests of males to raise only their own offspring. It has therefore been predicted, but never observed in the field, that if the female of a monogamous male is promiscuous, he will desert her and attempt to breed with an alternative female. Here we report a case of such a mate desertion in the aardwolf Proteles cristatus. We suggest, however, that mate desertion should occur only rarely in response to female promiscuity. This is because a cuckolded male may still be raising some of his own offspring, and should desert only on the rare occasions when an alternative receptive female is exclusively available to himself.  相似文献   
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